Search Results

Search found 12397 results on 496 pages for 'maybe'.

Page 489/496 | < Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >

• Google Chrome: JavaScript associative arrays, evaluated out of sequence

  - by Jerry

  Ok, so on a web page, I've got a JavaScript object which I'm using as an associative array. This exists statically in a script block when the page loads: var salesWeeks = { "200911" : ["11 / 2009", "Fiscal 2009"], "200910" : ["10 / 2009", "Fiscal 2009"], "200909" : ["09 / 2009", "Fiscal 2009"], "200908" : ["08 / 2009", "Fiscal 2009"], "200907" : ["07 / 2009", "Fiscal 2009"], "200906" : ["06 / 2009", "Fiscal 2009"], "200905" : ["05 / 2009", "Fiscal 2009"], "200904" : ["04 / 2009", "Fiscal 2009"], "200903" : ["03 / 2009", "Fiscal 2009"], "200902" : ["02 / 2009", "Fiscal 2009"], "200901" : ["01 / 2009", "Fiscal 2009"], "200852" : ["52 / 2008", "Fiscal 2009"], "200851" : ["51 / 2008", "Fiscal 2009"] }; The order of the key/value pairs is intentional, as I'm turning the object into an HTML select box such as this: <select id="ddl_sw" name="ddl_sw"> <option value="">== SELECT WEEK ==</option> <option value="200911">11 / 2009 (Fiscal 2009)</option> <option value="200910">10 / 2009 (Fiscal 2009)</option> <option value="200909">09 / 2009 (Fiscal 2009)</option> <option value="200908">08 / 2009 (Fiscal 2009)</option> <option value="200907">07 / 2009 (Fiscal 2009)</option> <option value="200906">06 / 2009 (Fiscal 2009)</option> <option value="200905">05 / 2009 (Fiscal 2009)</option> <option value="200904">04 / 2009 (Fiscal 2009)</option> <option value="200903">03 / 2009 (Fiscal 2009)</option> <option value="200902">02 / 2009 (Fiscal 2009)</option> <option value="200901">01 / 2009 (Fiscal 2009)</option> <option value="200852">52 / 2008 (Fiscal 2009)</option> <option value="200851">51 / 2008 (Fiscal 2009)</option> </select> ...with code that looks like this (snipped from a function): var arr = []; arr.push( "<select id=\"ddl_sw\" name=\"ddl_sw\">" + "<option value=\"\">== SELECT WEEK ==</option>" ); for(var key in salesWeeks) { arr.push( "<option value=\"" + key + "\">" + salesWeeks[key][0] + " (" + salesWeeks[key][1] + ")" + "<\/option>" ); } arr.push("<\/select>"); return arr.join(""); This all works fine in IE, FireFox and Opera. However in Chrome, the order comes out all weird: <select id="ddl_sw" name="ddl_sw"> <option value="">== SELECT WEEK ==</option> <option value="200852">52 / 2008 (Fiscal 2009)</option> <option value="200908">08 / 2009 (Fiscal 2009)</option> <option value="200906">06 / 2009 (Fiscal 2009)</option> <option value="200902">02 / 2009 (Fiscal 2009)</option> <option value="200907">07 / 2009 (Fiscal 2009)</option> <option value="200904">04 / 2009 (Fiscal 2009)</option> <option value="200909">09 / 2009 (Fiscal 2009)</option> <option value="200903">03 / 2009 (Fiscal 2009)</option> <option value="200905">05 / 2009 (Fiscal 2009)</option> <option value="200901">01 / 2009 (Fiscal 2009)</option> <option value="200910">10 / 2009 (Fiscal 2009)</option> <option value="200911">11 / 2009 (Fiscal 2009)</option> <option value="200851">51 / 2008 (Fiscal 2009)</option> </select> NOTE: This order, though weird, does not change on subsequent refreshes. It's always in this order. So, what is Chrome doing? Some optimization in how it processes the loop? In the first place, am I wrong to rely on the order that the key/value pairs are declared in any associative array? I never questioned it before, I just assumed the order would hold because this technique has always worked for me in the other browsers. But I suppose I've never seen it stated anywhere that the order is guaranteed. Maybe it's not? Any insight would be awesome. Thanks.

  Read the article

• Please help me correct the small bugs in this image editor

  - by Alex

  Hi, I'm working on a website that will sell hand made jewelry and I'm finishing the image editor, but it's not behaving quite right. Basically, the user uploads an image which will be saved as a source and then it will be resized to fit the user's screen and saved as a temp. The user will then go to a screen that will allow them to crop the image and then save it to it's final versions. All of that works fine, except, the final versions have 3 bugs. First is some black horizontal line on the very bottom of the image. Second is an outline of sorts that follows the edges. I thought it was because I was reducing the quality, but even at 100% it still shows up... And lastly, I've noticed that the cropped image is always a couple of pixels lower than what I'm specifying... Anyway, I'm hoping someone whose got experience in editing images with C# can maybe take a look at the code and see where I might be going off the right path. Oh, by the way, this in an ASP.NET MVC application. Here's the code: using System; using System.Drawing; using System.Drawing.Drawing2D; using System.Drawing.Imaging; using System.IO; using System.Linq; using System.Web; namespace Website.Models.Providers { public class ImageProvider { private readonly ProductProvider ProductProvider = null; private readonly EncoderParameters HighQualityEncoder = new EncoderParameters(); private readonly ImageCodecInfo JpegCodecInfo = ImageCodecInfo.GetImageEncoders().Single( c => (c.MimeType == "image/jpeg")); private readonly string Path = HttpContext.Current.Server.MapPath("~/Resources/Images/Products"); private readonly short[][] Dimensions = new short[3][] { new short[2] { 640, 480 }, new short[2] { 240, 0 }, new short[2] { 80, 60 } }; ////////////////////////////////////////////////////////// // Constructor ////////////////////////////////////////// ////////////////////////////////////////////////////////// public ImageProvider( ProductProvider ProductProvider) { this.ProductProvider = ProductProvider; HighQualityEncoder.Param[0] = new EncoderParameter(Encoder.Quality, 100L); } ////////////////////////////////////////////////////////// // Crop ////////////////////////////////////////////// ////////////////////////////////////////////////////////// public void Crop( string FileName, Image Image, Crop Crop) { using (Bitmap Source = new Bitmap(Image)) { using (Bitmap Target = new Bitmap(Crop.Width, Crop.Height)) { using (Graphics Graphics = Graphics.FromImage(Target)) { Graphics.InterpolationMode = InterpolationMode.HighQualityBicubic; Graphics.SmoothingMode = SmoothingMode.HighQuality; Graphics.PixelOffsetMode = PixelOffsetMode.HighQuality; Graphics.CompositingQuality = CompositingQuality.HighQuality; Graphics.DrawImage(Source, new Rectangle(0, 0, Target.Width, Target.Height), new Rectangle(Crop.Left, Crop.Top, Crop.Width, Crop.Height), GraphicsUnit.Pixel); }; Target.Save(FileName, JpegCodecInfo, HighQualityEncoder); }; }; } ////////////////////////////////////////////////////////// // Crop & Resize ////////////////////////////////////// ////////////////////////////////////////////////////////// public void CropAndResize( Product Product, Crop Crop) { using (Image Source = Image.FromFile(String.Format("{0}/{1}.source", Path, Product.ProductId))) { using (Image Temp = Image.FromFile(String.Format("{0}/{1}.temp", Path, Product.ProductId))) { float Percent = ((float)Source.Width / (float)Temp.Width); short Width = (short)(Temp.Width * Percent); short Height = (short)(Temp.Height * Percent); Crop.Height = (short)(Crop.Height * Percent); Crop.Left = (short)(Crop.Left * Percent); Crop.Top = (short)(Crop.Top * Percent); Crop.Width = (short)(Crop.Width * Percent); Img Img = new Img(); this.ProductProvider.AddImageAndSave(Product, Img); this.Crop(String.Format("{0}/{1}.cropped", Path, Img.ImageId), Source, Crop); using (Image Cropped = Image.FromFile(String.Format("{0}/{1}.cropped", Path, Img.ImageId))) { this.Resize(this.Dimensions[0], String.Format("{0}/{1}-L.jpg", Path, Img.ImageId), Cropped, HighQualityEncoder); this.Resize(this.Dimensions[1], String.Format("{0}/{1}-T.jpg", Path, Img.ImageId), Cropped, HighQualityEncoder); this.Resize(this.Dimensions[2], String.Format("{0}/{1}-S.jpg", Path, Img.ImageId), Cropped, HighQualityEncoder); }; }; }; this.Purge(Product); } ////////////////////////////////////////////////////////// // Queue ////////////////////////////////////////////// ////////////////////////////////////////////////////////// public void QueueFor( Product Product, HttpPostedFileBase PostedFile) { using (Image Image = Image.FromStream(PostedFile.InputStream)) { this.Resize(new short[2] { 1152, 0 }, String.Format("{0}/{1}.temp", Path, Product.ProductId), Image, HighQualityEncoder); }; PostedFile.SaveAs(String.Format("{0}/{1}.source", Path, Product.ProductId)); } ////////////////////////////////////////////////////////// // Purge ////////////////////////////////////////////// ////////////////////////////////////////////////////////// private void Purge( Product Product) { string Source = String.Format("{0}/{1}.source", Path, Product.ProductId); string Temp = String.Format("{0}/{1}.temp", Path, Product.ProductId); if (File.Exists(Source)) { File.Delete(Source); }; if (File.Exists(Temp)) { File.Delete(Temp); }; foreach (Img Img in Product.Imgs) { string Cropped = String.Format("{0}/{1}.cropped", Path, Img.ImageId); if (File.Exists(Cropped)) { File.Delete(Cropped); }; }; } ////////////////////////////////////////////////////////// // Resize ////////////////////////////////////////////// ////////////////////////////////////////////////////////// public void Resize( short[] Dimensions, string FileName, Image Image, EncoderParameters EncoderParameters) { if (Dimensions[1] == 0) { Dimensions[1] = (short)(Image.Height / ((float)Image.Width / (float)Dimensions[0])); }; using (Bitmap Bitmap = new Bitmap(Dimensions[0], Dimensions[1])) { using (Graphics Graphics = Graphics.FromImage(Bitmap)) { Graphics.InterpolationMode = InterpolationMode.HighQualityBicubic; Graphics.SmoothingMode = SmoothingMode.HighQuality; Graphics.PixelOffsetMode = PixelOffsetMode.HighQuality; Graphics.CompositingQuality = CompositingQuality.HighQuality; Graphics.DrawImage(Image, 0, 0, Dimensions[0], Dimensions[1]); }; Bitmap.Save(FileName, JpegCodecInfo, EncoderParameters); }; } } } Here's one of the images this produces:

  Read the article

• HttpModule Init method is called several times - why?

  - by MartinF

  I was creating a http module and while debugging I noticed something which at first (at least) seemed like weird behaviour. When i set a breakpoint in the init method of the httpmodule i can see that the http module init method is being called several times even though i have only started up the website for debugging and made one single request (sometimes it is hit only 1 time, other times as many as 10 times). I know that I should expect several instances of the HttpApplication to be running and for each the http modules will be created, but when i request a single page it should be handled by a single http application object and therefore only fire the events associated once, but still it fires the events several times for each request which makes no sense - other than it must have been added several times within that httpApplication - which means it is the same httpmodule init method which is being called every time and not a new http application being created each time it hits my break point (see my code example at the bottom etc.). What could be going wrong here ? is it because i am debugging and set a breakpoint in the http module? It have noticed that it seems that if i startup the website for debugging and quickly step over the breakpoint in the httpmodule it will only hit the init method once and the same goes for the eventhandler. If I instead let it hang at the breakpoint for a few seconds the init method is being called several times (seems like it depends on how long time i wait before stepping over the breakpoint). Maybe this could be some build in feature to make sure that the httpmodule is initialised and the http application can serve requests , but it also seems like something that could have catastrophic consequences. This could seem logical, as it might be trying to finish the request and since i have set the break point it thinks something have gone wrong and try to call the init method again ? soo it can handle the request ? But is this what is happening and is everything fine (i am just guessing), or is it a real problem ? What i am specially concerned about is that if something makes it hang on the "production/live" server for a few seconds a lot of event handlers are added through the init and therefore each request to the page suddenly fires the eventhandler several times. This behaviour could quickly bring any site down. I have looked at the "original" .net code used for the httpmodules for formsauthentication and the rolemanagermodule etc but my code isnt any different that those modules uses. My code looks like this. public void Init(HttpApplication app) { if (CommunityAuthenticationIntegration.IsEnabled) { FormsAuthenticationModule formsAuthModule = (FormsAuthenticationModule) app.Modules["FormsAuthentication"]; formsAuthModule.Authenticate += new FormsAuthenticationEventHandler(this.OnAuthenticate); } } here is an example how it is done in the RoleManagerModule from the .NET framework public void Init(HttpApplication app) { if (Roles.Enabled) { app.PostAuthenticateRequest += new EventHandler(this.OnEnter); app.EndRequest += new EventHandler(this.OnLeave); } } Do anyone know what is going on? (i just hope someone out there can tell me why this is happening and assure me that everything is perfectly fine) :) UPDATE: I have tried to narrow down the problem and so far i have found that the Init method being called is always on a new object of my http module (contary to what i thought before). I seems that for the first request (when starting up the site) all of the HttpApplication objects being created and its modules are all trying to serve the first request and therefore all hit the eventhandler that is being added. I cant really figure out why this is happening. If i request another page all the HttpApplication's created (and their moduless) will again try to serve the request causing it to hit the eventhandler multiple times. But it also seems that if i then jump back to the first page (or another one) only one HttpApplication will start to take care of the request and everything is as expected - as long as i dont let it hang at a break point. If i let it hang at a breakpoint it begins to create new HttpApplication's objects and starts adding HttpApplications (more than 1) to serve/handle the request (which is already in process of being served by the HttpApplication which is currently stopped at the breakpoint). I guess or hope that it might be some intelligent "behind the scenes" way of helping to distribute and handle load and / or errors. But I have no clue. I hope some out there can assure me that it is perfectly fine and how it is supposed to be?

  Read the article

• DataGrid rendering fails

  - by patryk.beza

  I have DataGrid with groups of data. The problem is that after binding data I have strange effect (text was blured by me; the problem are cells' paddings/margins). This effect can be easily 'fixed' by user because after one click on top expander data hides and after second click on the expander, rows in DataGrid are displayed correctly. My XAML code: <DataGrid Name="myDataGrid" Grid.Row="0" ItemsSource="{Binding}" AutoGenerateColumns="False" Background="White" RowBackground="#FBFFFA" AlternatingRowBackground="#EEFAEB" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"> <DataGrid.Columns> <!-- Columns definitions with binding ( . . . ) --> </DataGrid.Columns> <DataGrid.CellStyle> <Style TargetType="{x:Type DataGridCell}"> <Setter Property="Padding" Value="7,3"/> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="{x:Type DataGridCell}"> <Border Padding="{TemplateBinding Padding}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" SnapsToDevicePixels="True"> <ContentPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="Center" /> </Border> </ControlTemplate> </Setter.Value> </Setter> <Style.Triggers> <Trigger Property="DataGridCell.IsSelected" Value="True"> <Setter Property="Background"> <Setter.Value> <LinearGradientBrush EndPoint="0.504,1.5" StartPoint="0.504,0.03"> <GradientStop Color="#008C13" Offset="0"/> <GradientStop Color="#19FF38" Offset="0.8"/> </LinearGradientBrush> </Setter.Value> </Setter> </Trigger> </Style.Triggers> </Style> </DataGrid.CellStyle> <DataGrid.GroupStyle> <GroupStyle> <GroupStyle.HeaderTemplate> <DataTemplate> <StackPanel> <TextBlock Text="{Binding Path=Name}" FontWeight="Bold" Padding="3" /> </StackPanel> </DataTemplate> </GroupStyle.HeaderTemplate> <GroupStyle.ContainerStyle> <Style TargetType="{x:Type GroupItem}"> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="{x:Type GroupItem}"> <Expander> <Expander.Header> <StackPanel Orientation="Horizontal"> <TextBlock Text="Rok " /> <TextBlock Text="{Binding Name}" /> </StackPanel> </Expander.Header> <ItemsPresenter /> </Expander> </ControlTemplate> </Setter.Value> </Setter> </Style> </GroupStyle.ContainerStyle> </GroupStyle> </DataGrid.GroupStyle> </DataGrid> DataGrid's DataContext is set from code (rows with data in DataGrid are displayed after clicking proper button): ICollectionView myView = CollectionViewSource.GetDefaultView(myList); if (operationsView.GroupDescriptions.Count > 0) operationsView.GroupDescriptions.Clear(); operationsView.GroupDescriptions.Add(new PropertyGroupDescription("myGroupDescProperty")); FinancialIncomeOperationsListDataGrid.DataContext = operationsView; Is there any way to manually update layout of the DataGrid? Or maybe there is a better solution?

  Read the article

• Adding a JPanel to another JPanel having TableLayout

  - by user253530

  I am trying to develop a map editor in java. My map window receives as a constructor a Map object. From that map object i am able to retrieve the Grid and every item in the grid along with other getters and setters. The problem is that even though the Mapping extends JComponent, when I place it in a panel it is not painted. I have overridden the paint method to satisfy my needs. Here is the code, maybe you could help me. public class MapTest extends JFrame implements ActionListener { private JPanel mainPanel; private JPanel mapPanel; private JPanel minimapPanel; private JPanel relationPanel; private TableLayout tableLayout; private JPanel tile; MapTest(Map map) { mainPanel = (JPanel) getContentPane(); mapPanel = new JPanel(); populateMapPanel(map); mainPanel.add(mapPanel); this.setPreferredSize(new Dimension(800, 600)); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setVisible(true); } private double[][] generateTableLayoutSize(int x, int y, int size) { double panelSize[][] = new double[x][y]; for (int i = 0; i < x; i++) { for (int j = 0; j < y; j++) { panelSize[i][j] = size; } } return panelSize; } private void populateMapPanel(Map map) { double[][] layoutSize = generateTableLayoutSize(map.getMapGrid().getRows(), map.getMapGrid().getColumns(), 50); tableLayout = new TableLayout(layoutSize); for(int i = 0; i < map.getMapGrid().getRows(); i++) { for(int j = 0; j < map.getMapGrid().getColumns(); j++) { tile = new JPanel(); tile.setName(String.valueOf(((Mapping)map.getMapGrid().getItem(i, j)).getCharacter())); tile.add(map.getMapItem(i, j)); String constraint = i + "," + j; mapPanel.add(tile, constraint); } } mapPanel.validate(); mapPanel.repaint(); } public void actionPerformed(ActionEvent e) { throw new UnsupportedOperationException("Not supported yet."); } } My Mapping Class public class Mapping extends JComponent implements Serializable{ private BufferedImage image; private Character character; //default public Mapping() { super(); this.image = null; this.character = '\u0000'; } //Mapping from image and char public Mapping(BufferedImage image, char character) { super(); this.image = image; this.character = character; } //Mapping from file and char public Mapping(File file, char character) { try { this.image = ImageIO.read(file); this.character = character; } catch (IOException ex) { System.out.println(ex); } } public char getCharacter() { return character; } public void setCharacter(char character) { this.character = character; } public BufferedImage getImage() { return image; } public void setImage(BufferedImage image) { this.image = image; repaint(); } @Override /*Two mappings are consider the same if -they have the same image OR -they have the same character OR -both of the above*/ public boolean equals(Object mapping) { if (this == mapping) { return true; } if (mapping instanceof Mapping) { return true; } //WARNING! equals might not work for images return (this.getImage()).equals(((Mapping) mapping).getImage()) || (this.getCharacter()) == (((Mapping) mapping).getCharacter()); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); //g.drawImage(image, 0, 0, null); g.drawImage(image, 0, 0, this.getWidth(), this.getHeight(), null); } // @Override // public Dimension getPreferredSize() { // if (image == null) { // return new Dimension(10, 10); //instead of 100,100 set any prefered dimentions // } else { // return new Dimension(100, 100);//(image.getWidth(null), image.getHeight(null)); // } // } private void readObject(java.io.ObjectInputStream in) throws IOException, ClassNotFoundException { character = (Character) in.readObject(); image = ImageIO.read(ImageIO.createImageInputStream(in)); } private void writeObject(java.io.ObjectOutputStream out) throws IOException { out.writeObject(character); ImageWriter writer = (ImageWriter) ImageIO.getImageWritersBySuffix("jpg").next(); writer.setOutput(ImageIO.createImageOutputStream(out)); ImageWriteParam param = writer.getDefaultWriteParam(); param.setCompressionMode(ImageWriteParam.MODE_EXPLICIT); param.setCompressionQuality(0.85f); writer.write(null, new IIOImage(image, null, null), param); } }

  Read the article

• Tracking finger move in order to rotate a triangle : tracking is not perfect

  - by Laurent BERNABE

  I've written a custom view, with the OpenGL_1 technology, in order to let user rotate a red triangle just by dragging it along x axis. (Will give a rotation around Y axis). It works, but there is a bit of latency when dragging from one direction to the other (without releasing the mouse/finger). So it seems that my code is not yet "goal perfect". (I am convinced that no code is perfect in itself). I thought of using a quaternion, but maybe it won't be so usefull : must I really use a Quaternion (or a kind of Matrix) ? I've designed application for Android 4.0.3, but it could fit into Android api 3 (Android 1.5) as well (at least, I think it could). So here is my main layout : activity_main.xml <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <com.laurent_bernabe.android.triangletournant3d.MyOpenGLView android:layout_width="match_parent" android:layout_height="match_parent" /> </LinearLayout> Here is my main activity : MainActivity.java package com.laurent_bernabe.android.triangletournant3d; import android.app.Activity; import android.os.Bundle; import android.support.v4.app.NavUtils; import android.view.Menu; import android.view.MenuItem; public class MainActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.activity_main, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case android.R.id.home: NavUtils.navigateUpFromSameTask(this); return true; } return super.onOptionsItemSelected(item); } } And finally, my OpenGL view MyOpenGLView.java package com.laurent_bernabe.android.triangletournant3d; import java.nio.ByteBuffer; import java.nio.ByteOrder; import java.nio.FloatBuffer; import javax.microedition.khronos.egl.EGLConfig; import javax.microedition.khronos.opengles.GL10; import android.content.Context; import android.graphics.Point; import android.opengl.GLSurfaceView; import android.opengl.GLSurfaceView.Renderer; import android.opengl.GLU; import android.util.AttributeSet; import android.view.MotionEvent; public class MyOpenGLView extends GLSurfaceView implements Renderer { public MyOpenGLView(Context context, AttributeSet attrs) { super(context, attrs); setRenderer(this); } public MyOpenGLView(Context context) { this(context, null); } @Override public boolean onTouchEvent(MotionEvent event) { int actionMasked = event.getActionMasked(); switch(actionMasked){ case MotionEvent.ACTION_DOWN: savedClickLocation = new Point((int) event.getX(), (int) event.getY()); break; case MotionEvent.ACTION_UP: savedClickLocation = null; break; case MotionEvent.ACTION_MOVE: Point newClickLocation = new Point((int) event.getX(), (int) event.getY()); int dx = newClickLocation.x - savedClickLocation.x; angle += Math.toRadians(dx); break; } return true; } @Override public void onDrawFrame(GL10 gl) { gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT); gl.glLoadIdentity(); GLU.gluLookAt(gl, 0f, 0f, 5f, 0f, 0f, 0f, 0f, 1f, 0f ); gl.glRotatef(angle, 0f, 1f, 0f); gl.glColor4f(1f, 0f, 0f, 0f); gl.glVertexPointer(2, GL10.GL_FLOAT, 0, triangleCoordsBuff); gl.glDrawArrays(GL10.GL_TRIANGLES, 0, 3); } @Override public void onSurfaceChanged(GL10 gl, int width, int height) { gl.glViewport(0, 0, width, height); gl.glMatrixMode(GL10.GL_PROJECTION); gl.glLoadIdentity(); GLU.gluPerspective(gl, 60f, (float) width / height, 0.1f, 10f); gl.glMatrixMode(GL10.GL_MODELVIEW); } @Override public void onSurfaceCreated(GL10 gl, EGLConfig config) { gl.glEnable(GL10.GL_DEPTH_TEST); gl.glClearDepthf(1.0f); gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); buildTriangleCoordsBuffer(); } private void buildTriangleCoordsBuffer() { ByteBuffer buffer = ByteBuffer.allocateDirect(4*triangleCoords.length); buffer.order(ByteOrder.nativeOrder()); triangleCoordsBuff = buffer.asFloatBuffer(); triangleCoordsBuff.put(triangleCoords); triangleCoordsBuff.rewind(); } private float [] triangleCoords = {-1f, -1f, +1f, -1f, +1f, +1f}; private FloatBuffer triangleCoordsBuff; private float angle = 0f; private Point savedClickLocation; } I don't think I really have to give you my manifest file. But I can if you think it is necessary. I've just tested on Emulator, not on real device. So, how can improve the reactivity ? Thanks in advance.

  Read the article

• Convert C++Builder AnsiString to std::string via boost::lexical_cast

  - by David Klein

  For a school assignment I have to implement a project in C++ using Borland C++ Builder. As the VCL uses AnsiString for all GUI Components I have to convert all of my std::strings to AnsiString for the sake of displaying. std::string inp = "Hello world!"; AnsiString outp(inp.c_str()); works of course but is a bit tedious to write and code duplication I want to avoid. As we use Boost in other contexts I decided to provide some helper functions go get boost::lexical_cast to work with AnsiString. Here is my implementation so far: std::istream& operator>>(std::istream& istr, AnsiString& str) { istr.exceptions(std::ios::badbit | std::ios::failbit | std::ios::eofbit); std::string s; std::getline(istr,s); str = AnsiString(s.c_str()); return istr; } In the beginning I got Access Violation after Access Violation but since I added the .exceptions() stuff the picture gets clearer. When the conversion is performed I get the following Exception: ios_base::eofbit set [Runtime Error/std::ios_base::failure] Does anyone have an idea how to fix it and can explain why the error occurs? My C++ experience is very limited. The conversion routine the other way round would be: std::ostream& operator<<(std::ostream& ostr,const AnsiString& str) { ostr << (str.c_str()); return ostr; } Maybe someone will spot an error here too :) With best regards! Edit: At the moment I'm using the edited version of Jem, it works in the beginning. After a while of using the programm the Borland Codeguard mentions some pointer arithmetic in already freed regions. Any ideas how this could be related? The Codeguard log (I'm using the german version, translations marked with stars): ------------------------------------------ Fehler 00080. 0x104230 (r) (Thread 0x07A4): Zeigerarithmetik in freigegebenem Speicher: 0x0241A238-0x0241A258. **(pointer arithmetic in freed region)** | d:\program files\borland\bds\4.0\include\dinkumware\sstream Zeile 126: | { // not first growth, adjust pointers | _Seekhigh = _Seekhigh - _Mysb::eback() + _Ptr; |> _Mysb::setp(_Mysb::pbase() - _Mysb::eback() + _Ptr, | _Mysb::pptr() - _Mysb::eback() + _Ptr, _Ptr + _Newsize); | if (_Mystate & _Noread) Aufrufhierarchie: **(stack-trace)** 0x00411731(=FOSChampion.exe:0x01:010731) d:\program files\borland\bds\4.0\include\dinkumware\sstream#126 0x00411183(=FOSChampion.exe:0x01:010183) d:\program files\borland\bds\4.0\include\dinkumware\streambuf#465 0x0040933D(=FOSChampion.exe:0x01:00833D) d:\program files\borland\bds\4.0\include\dinkumware\streambuf#151 0x00405988(=FOSChampion.exe:0x01:004988) d:\program files\borland\bds\4.0\include\dinkumware\ostream#679 0x00405759(=FOSChampion.exe:0x01:004759) D:\Projekte\Schule\foschamp\src\Server\Ansistringkonverter.h#31 0x004080C9(=FOSChampion.exe:0x01:0070C9) D:\Projekte\Schule\foschamp\lib\boost_1_34_1\boost/lexical_cast.hpp#151 Objekt (0x0241A238) [Größe: 32 Byte] war erstellt mit new **(Object was created with new)** | d:\program files\borland\bds\4.0\include\dinkumware\xmemory Zeile 28: | _Ty _FARQ *_Allocate(_SIZT _Count, _Ty _FARQ *) | { // allocate storage for _Count elements of type _Ty |> return ((_Ty _FARQ *)::operator new(_Count * sizeof (_Ty))); | } | Aufrufhierarchie: **(stack-trace)** 0x0040ED90(=FOSChampion.exe:0x01:00DD90) d:\program files\borland\bds\4.0\include\dinkumware\xmemory#28 0x0040E194(=FOSChampion.exe:0x01:00D194) d:\program files\borland\bds\4.0\include\dinkumware\xmemory#143 0x004115CF(=FOSChampion.exe:0x01:0105CF) d:\program files\borland\bds\4.0\include\dinkumware\sstream#105 0x00411183(=FOSChampion.exe:0x01:010183) d:\program files\borland\bds\4.0\include\dinkumware\streambuf#465 0x0040933D(=FOSChampion.exe:0x01:00833D) d:\program files\borland\bds\4.0\include\dinkumware\streambuf#151 0x00405988(=FOSChampion.exe:0x01:004988) d:\program files\borland\bds\4.0\include\dinkumware\ostream#679 Objekt (0x0241A238) war Gelöscht mit delete **(Object was deleted with delete)** | d:\program files\borland\bds\4.0\include\dinkumware\xmemory Zeile 138: | void deallocate(pointer _Ptr, size_type) | { // deallocate object at _Ptr, ignore size |> ::operator delete(_Ptr); | } | Aufrufhierarchie: **(stack-trace)** 0x004044C6(=FOSChampion.exe:0x01:0034C6) d:\program files\borland\bds\4.0\include\dinkumware\xmemory#138 0x00411628(=FOSChampion.exe:0x01:010628) d:\program files\borland\bds\4.0\include\dinkumware\sstream#111 0x00411183(=FOSChampion.exe:0x01:010183) d:\program files\borland\bds\4.0\include\dinkumware\streambuf#465 0x0040933D(=FOSChampion.exe:0x01:00833D) d:\program files\borland\bds\4.0\include\dinkumware\streambuf#151 0x00405988(=FOSChampion.exe:0x01:004988) d:\program files\borland\bds\4.0\include\dinkumware\ostream#679 0x00405759(=FOSChampion.exe:0x01:004759) D:\Projekte\Schule\foschamp\src\Server\Ansistringkonverter.h#31 ------------------------------------------ Ansistringkonverter.h is the file with the posted operators and line 31 is: std::ostream& operator<<(std::ostream& ostr,const AnsiString& str) { ostr << (str.c_str()); **(31)** return ostr; } Thanks for your help :)

  Read the article

• Trying to Add Insert Row to Footer in GridView ASP.net

  - by chillconsulting

  I'm trying to give the user the ability to create a new record from the footer row and my event handler doesn't seem to be working... or maybe I'm going at this all wrong. The insert button that I enabled in the gridview doesn't work either...checkout the site at http://aisched.engr.oregonstate.edu/admin/courses.aspx Here is my code in front and behind: public partial class admin_courses : System.Web.UI.Page { public Table table; ListDictionary listValues = new ListDictionary(); TextBox textBox1 = new TextBox(); //Name TextBox textBox2 = new TextBox(); //CR TextBox textBox3 = new TextBox(); //CourseNum TextBox textBox4 = new TextBox(); //Dept protected void Page_Init() { } protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e) { if (e.Row.RowType != DataControlRowType.Footer) return; //Escape if not footer textBox1.ID = "name"; textBox1.Width = 250; textBox2.ID = "credit_hours"; textBox2.Width = 25; textBox3.ID = "dept"; textBox3.Width = 30; textBox4.ID = "class"; textBox4.Width = 25; LinkButton add = new LinkButton(); add.ID = "add"; add.Text = "Add course"; add.CommandName = "add"; add.Click += new EventHandler(add_Click); e.Row.Cells[1].Controls.Add(textBox1); e.Row.Cells[2].Controls.Add(textBox2); e.Row.Cells[3].Controls.Add(textBox3); e.Row.Cells[4].Controls.Add(textBox4); e.Row.Cells[5].Controls.Add(add); } public void add_Click(object sender, EventArgs e) { Response.Write("you Clicked Add Course!"); if (textBox1.Text != null && textBox2.Text != null && textBox3.Text != null && textBox4.Text != null) { listValues.Add("name", textBox1.Text); listValues.Add("credit_hours", textBox2.Text); listValues.Add("dept", textBox4.Text); //For Visual listValues.Add("class", textBox3.Text); } LinqDataSource1.Insert(listValues); Response.Redirect("~/admin/courses.aspx"); } } <%@ Page Language="C#" MasterPageFile="~/admin.master" AutoEventWireup="true" CodeFile="courses.aspx.cs" Inherits="admin_courses" Title="OSU Aisched | Admin - Courses" %> <%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %> <asp:Content ID="Content1" ContentPlaceHolderID="admin_nav_links" Runat="Server"> <ul id="main"> <li><a href="overview.aspx">Overview</a></li> <li><a href="users.aspx">Users</a></li> <li class="current_page_item"><a href="courses.aspx">Courses</a></li> <li><a href="programs.aspx">Programs</a></li> <li><a href="sections.aspx">Sections</a></li> <li><a href="import.aspx">Import</a></li> <li><a href="logs.aspx">Logs</a></li> </ul> </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server"> <form id="Form1" runat="server"> <asp:ScriptManager ID="ScriptManager1" runat="server"> </asp:ScriptManager> <asp:LinqDataSource ID="LinqDataSource1" runat="server" ContextTypeName="DataClassesDataContext" EnableDelete="True" EnableInsert="True" EnableUpdate="True" TableName="courses"> </asp:LinqDataSource> <h1><a>Courses</a></h1> <asp:UpdateProgress ID="UpdateProgress1" runat="server"> </asp:UpdateProgress> <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="course_id" DataSourceID="LinqDataSource1" BackColor="#DEBA84" BorderColor="#DEBA84" BorderStyle="None" BorderWidth="1px" CellPadding="3" CellSpacing="2" AllowSorting="True" ShowFooter="True" OnRowDataBound="GridView1_RowDataBound" > <RowStyle BackColor="#FFF7E7" ForeColor="#8C4510" /> <Columns> <asp:BoundField DataField="course_id" HeaderText="ID" ReadOnly="True" SortExpression="course_id" /> <asp:BoundField DataField="name" HeaderText="Name" SortExpression="name" /> <asp:BoundField DataField="credit_hours" HeaderText="CR" SortExpression="credit_hours" /> <asp:BoundField DataField="dept" HeaderText="Dept" SortExpression="dept" /> <asp:BoundField DataField="class" HeaderText="#" SortExpression="class" /> <asp:CommandField DeleteImageUrl="~/media/delete.png" ShowDeleteButton="True" ShowEditButton="True" ShowInsertButton="True"/> </Columns> <FooterStyle BackColor="#F7DFB5" ForeColor="#8C4510" /> <PagerStyle ForeColor="#8C4510" HorizontalAlign="Center" /> <SelectedRowStyle BackColor="#738A9C" Font-Bold="True" ForeColor="White" /> <HeaderStyle BackColor="#A55129" Font-Bold="True" ForeColor="White" /> </asp:GridView> <br /> <asp:HyperLink ID="HyperLink1" runat="server" Target="~/admin/addCourse.aspx" Enabled="true"NavigateUrl="~/admin/addCourse.aspx" Text="Add New course"></asp:HyperLink> <br /> </form> </asp:Content>

  Read the article

• Signals and threads - good or bad design decision?

  - by Jens

  I have to write a program that performs highly computationally intensive calculations. The program might run for several days. The calculation can be separated easily in different threads without the need of shared data. I want a GUI or a web service that informs me of the current status. My current design uses BOOST::signals2 and BOOST::thread. It compiles and so far works as expected. If a thread finished one iteration and new data is available it calls a signal which is connected to a slot in the GUI class. My question(s): Is this combination of signals and threads a wise idea? I another forum somebody advised someone else not to "go down this road". Are there potential deadly pitfalls nearby that I failed to see? Is my expectation realistic that it will be "easy" to use my GUI class to provide a web interface or a QT, a VTK or a whatever window? Is there a more clever alternative (like other boost libs) that I overlooked? following code compiles with g++ -Wall -o main -lboost_thread-mt <filename>.cpp code follows: #include <boost/signals2.hpp> #include <boost/thread.hpp> #include <boost/bind.hpp> #include <iostream> #include <iterator> #include <string> using std::cout; using std::cerr; using std::string; /** * Called when a CalcThread finished a new bunch of data. */ boost::signals2::signal<void(string)> signal_new_data; /** * The whole data will be stored here. */ class DataCollector { typedef boost::mutex::scoped_lock scoped_lock; boost::mutex mutex; public: /** * Called by CalcThreads call the to store their data. */ void push(const string &s, const string &caller_name) { scoped_lock lock(mutex); _data.push_back(s); signal_new_data(caller_name); } /** * Output everything collected so far to std::out. */ void out() { typedef std::vector<string>::const_iterator iter; for (iter i = _data.begin(); i != _data.end(); ++i) cout << " " << *i << "\n"; } private: std::vector<string> _data; }; /** * Several of those can calculate stuff. * No data sharing needed. */ struct CalcThread { CalcThread(string name, DataCollector &datcol) : _name(name), _datcol(datcol) { } /** * Expensive algorithms will be implemented here. * @param num_results how many data sets are to be calculated by this thread. */ void operator()(int num_results) { for (int i = 1; i <= num_results; ++i) { std::stringstream s; s << "["; if (i == num_results) s << "LAST "; s << "DATA " << i << " from thread " << _name << "]"; _datcol.push(s.str(), _name); } } private: string _name; DataCollector &_datcol; }; /** * Maybe some VTK or QT or both will be used someday. */ class GuiClass { public: GuiClass(DataCollector &datcol) : _datcol(datcol) { } /** * If the GUI wants to present or at least count the data collected so far. * @param caller_name is the name of the thread whose data is new. */ void slot_data_changed(string caller_name) const { cout << "GuiClass knows: new data from " << caller_name << std::endl; } private: DataCollector & _datcol; }; int main() { DataCollector datcol; GuiClass mc(datcol); signal_new_data.connect(boost::bind(&GuiClass::slot_data_changed, &mc, _1)); CalcThread r1("A", datcol), r2("B", datcol), r3("C", datcol), r4("D", datcol), r5("E", datcol); boost::thread t1(r1, 3); boost::thread t2(r2, 1); boost::thread t3(r3, 2); boost::thread t4(r4, 2); boost::thread t5(r5, 3); t1.join(); t2.join(); t3.join(); t4.join(); t5.join(); datcol.out(); cout << "\nDone" << std::endl; return 0; }

  Read the article

• website creation - for non web programmers?

  - by Tim

  I thought I would find decent questions and answers for this, but none really caught my eye... I am a C++ developer and I own a few domains. I'd like to start off with simple web sites for each with a minimum of time and fuss and minimum learning. I have too many projects going and don't have the time to learn how to build websites. One is for a company that currently has only a single product with custom development as well. I hacked together some really bad html with paypal links on it. It is just one simple product. I want to add uservoice to it and maybe some other stuff like FAQ, forums, etc. Right now I just link to a google group I created. Another is a startup in development phase, but we want to provide simple content like whitepapers and press releases and a section for investors. - mostly an "about us" type of thing. We will also be providing details about our product. Then there is a blog site - currently using godaddy's quickblogcast. Not a bad start but I suspect I want to move to something else. The question is - is there a framework that I can use that will make decent, if not outstanding, sites? Again, I have my hands full with three projects in addition to my day job and don't have time to learn web programming. I also don;t want to just pay a web person and then be out in the cold for upgrades, changes, etc. I have been burned before. I am happy with a web-based app or a desktop app that builds html or whatever and then I can ftp it up to the hosting servers. To summarize: - simple to get started - low time to get a web page going - ability to integrate with a few hand-done pages - pay pal integration - uservoice integration - ability to put under my svn would be nice too EDIT Thanks to the responders. I understand now why my original searches failed. I was not searching for "CMS". I'll go back and do that. I would expect that this is a many-times-duplicate... EDIT: I am considering using Wordpress and Drupal - one for each of the sites. I did one Drupal site quickly just so I could qualify for one of the Microsoft programs for discounted dev tools - anyway - it was a quick and dirty homepage and I am still on the learning curve. I look forward to playing with it. So far it has been ok. I am not sure about doing a taste-test between the two - might be a waste of time where I could just become that much better at Drupal faster than spending time on wordpress... Will keep updated. EDIT: Selecting the Drupal answer by slim for now. That is what I am going with. Don't have time to check them all out. Wordpress sounds like a good option too, but such limited time... Results: I have tried wordpress and drupal so far. Wordpress is great for blogging or for a site that you want to run ads from, but I disagree that it is ready for a corporate site, unless you want to spend lots of time making your own theme, etc. But if you spend that time, why not work with drupal? Drupal was a little intimidating at first - but after spending about 4 hours reading the overview and step-by-step guide online was a HUGE step. I got a simple site up and running easily after that. Trying to make a website just by going to the admin panel without reading anything is a waste of time. You really need to read the docs. The site is great. start here: http://drupal.org/getting-started I'd suggest drupal to anyone. It has amazing capabilities, lots of support and lots of users. Just doing blogging? Wordpress is really great for that. So now I've got two sites running with a lot of the functionality I wanted - and they look good. ONE MORE EDIT Well, I have switched back to wordpress after buying a theme and then getting help from web developers. I guess either one will work - it is just a matter of getting comfortable witht he basics, using the right tools and trying things out.

  Read the article

• Optimizing a 3D World Javascript Animation

  - by johnny

  Hi! I've recently come up with the idea to create a tag cloud like animation shaped like the earth. I've extracted the coastline coordinates from ngdc.noaa.gov and wrote a little script that displayed it in my browser. Now as you can imagine, the whole coastline consists of about 48919 points, which my script would individually render (each coordinate being represented by one span). Obviously no browser is capable of rendering this fluently - but it would be nice if I could render as much as let's say 200 spans (twice as much as now) on my old p4 2.8 Ghz (as a representative benchmark). Are there any javascript optimizations I could use in order to speed up the display of those spans? One 'coordinate': <div id="world_pixels"> <span id="wp_0" style="position:fixed; top:0px; left:0px; z-index:1; font-size:20px; cursor:pointer;cursor:hand;" onmouseover="magnify_world_pixel('wp_0');" onmouseout="shrink_world_pixel('wp_0');" onClick="set_askcue_bar('', 'new york')">new york</span> </div> The script: $(document).ready(function(){ world_pixels = $("#world_pixels span"); world_pixels.spin(); setInterval("world_pixels.spin()",1500); }); z = new Array(); $.fn.spin = function () { for(i=0; i<this.length; i++) { /*actual screen coordinates: x/y/z --> left/font-size/top 300/13/0 300/6/300 | / |/ 0/13/300 ----|---- 600/13/300 /| / | 300/20/300 300/13/600 */ /*scale font size*/ var resize_x = 1; /*scale width*/ var resize_y = 2.5; /*scale height*/ var resize_z = 2.5; var from_left = 300; var from_top = 20; /*actual math coordinates: 1 -1 | / |/ 1 ----|---- -1 /| / | 1 -1 */ //var get_element = document.getElementById(); //var font_size = parseInt(this.style.fontSize); var font_size = parseInt($(this[i]).css("font-size")); var left = parseInt($(this[i]).css("left")); if (coast_line_array[i][1]) { } else { var top = parseInt($(this[i]).css("top")); z[i] = from_top + (top - (300 * resize_z)) / (300 * resize_z); //global beacause it's used in other functions later on var top_new = from_top + Math.round(Math.cos(coast_line_array[i][2]/90*Math.PI) * (300 * resize_z) + (300 * resize_z)); $(this[i]).css("top", top_new); coast_line_array[i][3] = 1; } var x = resize_x * (font_size - 13) / 7; var y = from_left + (left- (300 * resize_y)) / (300 * resize_y); if (y >= 0) { this[i].phi = Math.acos(x/(Math.sqrt(x^2 + y^2))); } else { this[i].phi = 2*Math.PI - Math.acos(x/(Math.sqrt(x^2 + y^2))); i } this[i].theta = Math.acos(z[i]/Math.sqrt(x^2 + y^2 + z[i]^2)); var font_size_new = resize_x * Math.round(Math.sin(coast_line_array[i][4]/90*Math.PI) * Math.cos(coast_line_array[i][0]/180*Math.PI) * 7 + 13); var left_new = from_left + Math.round(Math.sin(coast_line_array[i][5]/90*Math.PI) * Math.sin(coast_line_array[i][0]/180*Math.PI) * (300 * resize_y) + (300 * resize_y)); //coast_line_array[i][6] = coast_line_array[i][7]+1; if ((coast_line_array[i][0] + 1) > 180) { coast_line_array[i][0] = -180; } else { coast_line_array[i][0] = coast_line_array[i][0] + 0.25; } $(this[i]).css("font-size", font_size_new); $(this[i]).css("left", left_new); } } resize_x = 1; function magnify_world_pixel(element) { $("#"+element).animate({ fontSize: resize_x*30+"px" }, { duration: 1000 }); } function shrink_world_pixel(element) { $("#"+element).animate({ fontSize: resize_x*6+"px" }, { duration: 1000 }); } I'd appreciate any suggestions to optimize my script, maybe there is even a totally different approach on how to go about this. The whole .js file which stores the array for all the coordinates is available on my page, the file is about 2.9 mb, so you might consider pulling the .zip for local testing: metaroulette.com/files/31218.zip metaroulette.com/files/31218.js P.S. the php I use to create the spans: <?php //$arbitrary_characters = array('a','b','c','ddsfsdfsdf','e','f','g','h','isdfsdffd','j','k','l','mfdgcvbcvbs','n','o','p','q','r','s','t','uasdfsdf','v','w','x','y','z','0','1','2','3','4','5','6','7','8','9',); $arbitrary_characters = array('cat','table','cool','deloitte','askcue','what','more','less','adjective','nice','clinton','mars','jupiter','testversion','beta','hilarious','lolcatz','funny','obama','president','nice','what','misplaced','category','people','religion','global','skyscraper','new york','dubai','helsinki','volcano','iceland','peter','telephone','internet', 'dialer', 'cord', 'movie', 'party', 'chris', 'guitar', 'bentley', 'ford', 'ferrari', 'etc', 'de facto'); for ($i=0; $i<96; $i++) { $arb_digits = rand (0,45); $arbitrary_character = $arbitrary_characters[$arb_digits]; //$arbitrary_character = "."; echo "<span id=\"wp_$i\" style=\"position:fixed; top:0px; left:0px; z-index:1; font-size:20px; cursor:pointer;cursor:hand;\" onmouseover=\"magnify_world_pixel('wp_$i');\" onmouseout=\"shrink_world_pixel('wp_$i');\" onClick=\"set_askcue_bar('', '$arbitrary_character')\">$arbitrary_character</span>\n"; } ?>

  Read the article

• Am I crazy? (How) should I create a jQuery content editor?

  - by Brendon Muir

  Ok, so I created a CMS mainly aimed at Primary Schools. It's getting fairly popular in New Zealand but the one thing I hate with a passion is the largely bad quality of in browser WYSIWYG editors. I've been using KTML (made by InterAKT which was purchased by Adobe a few years ago). In my opinion this editor does a lot of great things (image editing/management, thumbnailing and pretty good content editing). Unfortunately time has had its nasty way with this product and new browsers are beginning to break features and generally degrade the performance of this tool. It's also quite scary basing my livelihood on a defunct product! I've been hunting, in fact I regularly hunt around to see if anything has changed in the WYSIWYG arena. The closest thing I've seen that excites me is the WYSIHAT framework, but they've decided to ignore a pretty relevant editing paradigm which I'm going to outline below. This is the idea for my proposed editor, and I don't know of any existing products that can do this properly: Right, so the traditional model for editing let's say a Page in a CMS is to log into a 'back end' and click edit on the page. This will then load another screen with the editor in it and perhaps a few other fields. More advanced CMS's will maybe have several editing boxes that are for different portions of the page. Anyway, the big problem with this way of doing things is that the user is editing a document outside of the final context it will appear in. In the simplest terms, this means the page template. Many things can be wrong, e.g. the with of the editing area might be different to the width of the actual template area. The height is nearly always fixed because existing editors always seem to use IFRAMES for backward compatibility. And there are plenty of other beefs which I'm sure you're quite aware of if you're in this development area. Here's my editor utopia: You click 'Edit Page': The actual page (with its actual template) displays. Portions of the page have been marked as editable via a class name. You click on one of these areas (in my case it'd just be the big 'body' area in the middle of the template) and a editing bar drops down from the top of the screen with all your standard controls (bold, italic, insert image etc...). Iframes are never used, instead we rely on setting contentEditable to true on the DIV's in question. Firefox 2 and IE6 can go away, let's move on. You can edit the page knowing exactly how it will look when you save it. Because all the styles for this template are loaded, your headings will look correct, everything will be just dandy. Is this such a radical concept? Why are we still content with TinyMCE and that other editor that is too embarrassing to use because it sounds like a swear word!? Let's face the facts: I'm a JavaScript novice. I did once play around in this area using the Javascript Anthology from SitePoint as a guide. It was quite a cool learning experience, but they of course used the IFRAME to make their lives easier. I tried to go a different route and just use contentEditable and even tried to sidestep the native content editing routines (execCommand) and instead wrote my own. They kind of worked but there were always issues. Now we have jQuery, and a few libraries that abstract things like IE's lack of Range support. I'm wondering, am I crazy, or is it actually a good idea to try and build an editor around this editing paradigm using jQuery and relevant plugins to make the job easier? My actual questions: Where would you start? What plugins do you know of that would help the most? Is it worth it, or is there a magical project that already exists that I should join in on? What are the biggest hurdles to overcome in a project like this? Am I crazy? I hope this question has been posted on the right board. I figured it is a technical question as I'm wanting to know specific hurdles and pitfalls to watch out for and also if it is technically feasible with todays technology. Looking forward to hearing peoples thoughts and opinions.

  Read the article

• Wisdom of merging 100s of Oracle instances into one instance

  - by hoytster

  Our application runs on the web, is mostly an inquiry tool, does some transactions. We host the Oracle database. The app has always had a different instance of Oracle for each customer. A customer is a company which pays us to provide our service to the company's employees, typically 10,000-25,000 employees per customer. We do a major release every few years, and migrating to that new release is challenging: we might have a team at the customer site for a couple weeks, explaining new functionality and setting up the driving data to suit that customer. We're considering going multi-client, putting all our customers into a single shared Oracle 11g instance on a big honkin' Windows Server 2008 server -- in order to reduce costs. I'm wondering if that's advisable. There are some advantages to having separate instances for each customer. Tell me if these are bogus, please. In my rough guess about decreasing importance: Our customers MyCorp and YourCo can be migrated separately when breaking changes are made to the schema. (With multi-client, we'd be migrating 300+ customers overnight!?!) MyCorp's data can be easily backed up and (!!!) restored, without affecting other customers. MyCorp's data is securely separated from their competitor YourCo's data, without depending on developers to get the code right and/or DBAs getting the configuration right. Performance is better because the database is smaller (5,000 vs 2,000,000 rows in ~50 tables). If MyCorp's offices are (mostly) in just one region, then the MyCorp's instance can be geographically co-located there, so network lag doesn't hurt performance. We can provide better service to global clients, for the same reason. In MyCorp wants to take their database in-house, then we can easily export their instance, to get MyCorp their data. Load-balancing is easier because instances can be placed on different servers (this is with a web farm). When a DEV or QA instance is needed, it's easier to clone the real instance and anonymize the data, because there's much less data. Because they're small enough, developers can have their own instance running locally, so they can work on code while waiting at the airport and while in-flight, without fighting VPN hassles. Q1: What are other advantages of separate instances? We are contemplating changing the database schema and merging all of our customers into one Oracle instance, running on one hefty server. Here are advantages of the multi-client instance approach, most important first (my WAG). Please snipe if these are bogus: Less work for the DBAs, since they only need to maintain one instance instead of hundreds. Less DBA work translates to cheaper, our main motive for this change. With just one instance, the DBAs can do a better job of optimizing performance. They'll have time to add appropriate indexes and review our SQL. It will be easier for developers to debug & enhance the application, because there is only one schema and one app (there might be dozens of schema versions if there are hundreds of instances, with a different version of the app for each version of the schema). This reduces costs too. The alternative is having to start every debug session with (1) What version is this customer running and (2) Let's struggle to recreate the corresponding development environment, code and database. (We need a Virtual Machine that includes the code AND database instance for each patch and release!) Licensing Oracle is cheaper because it's priced per server irrespective of heft (or something -- I don't know anything about the subject). The database becomes a viable persistent store for web session data, because there is just one instance. Some database operations are easier with one multi-client instance, like finding a participant when they're hazy about which customer they (or their spouse, maybe) works for: all the names are in one table. Reporting across customers is straightforward. Q2: What are other advantages of having multiple clients in one instance? Q3: Which approach do you think is better (why)? Instance per customer, or all customers in one instance? I'm concerned that having one multi-client instance makes migration near-impossible, and that's a deal killer... ... unless there is a compromise solution like having two multi-client instances, the old and the new. In that case case, we would design cross-instance solutions for finding participants, reporting, etc. so customers could go from one multi-client instance to the next without anything breaking. THANKS SO MUCH for your collective advice! This issue is beyond me -- but not beyond the collective you. :) Hoytster

  Read the article

• Stack overflow error after creating a instance using 'new'

  - by Justin

  EDIT - The code looks strange here, so I suggest viewing the files directly in the link given. While working on my engine, I came across a issue that I'm unable to resolve. Hoping to fix this without any heavy modification, the code is below. void Block::DoCollision(GameObject* obj){ obj->DoCollision(this); } That is where the stack overflow occurs. This application works perfectly fine until I create two instances of the class using the new keyword. If I only had 1 instance of the class, it worked fine. Block* a = new Block(0, 0, 0, 5); AddGameObject(a); a = new Block(30, 0, 0, 5); AddGameObject(a); Those parameters are just x,y,z and size. The code is checked before hand. Only a object with a matching Collisonflag and collision type will trigger the DoCollision(); function. ((*list1)->m_collisionFlag & (*list2)->m_type) Maybe my check is messed up though. I attached the files concerned here http://celestialcoding.com/index.php?topic=1465.msg9913;topicseen#new. You can download them without having to sign up. The main suspects, I also pasted the code for below. From GameManager.cpp void GameManager::Update(float dt){ GameList::iterator list1; for(list1=m_gameObjectList.begin(); list1 != m_gameObjectList.end(); ++list1){ GameObject* temp = *list1; // Update logic and positions if((*list1)->m_active){ (*list1)->Update(dt); // Clip((*list1)->m_position); // Modify for bounce affect } else continue; // Check for collisions if((*list1)->m_collisionFlag != GameObject::TYPE_NONE){ GameList::iterator list2; for(list2=m_gameObjectList.begin(); list2 != m_gameObjectList.end(); ++list2){ if(!(*list2)->m_active) continue; if(list1 == list2) continue; if( (*list2)->m_active && ((*list1)->m_collisionFlag & (*list2)->m_type) && (*list1)->IsColliding(*list2)){ (*list1)->DoCollision((*list2)); } } } if(list1==m_gameObjectList.end()) break; } GameList::iterator end    = m_gameObjectList.end(); GameList::iterator newEnd = remove_if(m_gameObjectList.begin(),m_gameObjectList.end(),RemoveNotActive); if(newEnd != end)        m_gameObjectList.erase(newEnd,end); } void GameManager::LoadAllFiles(){ LoadSkin(m_gameTextureList, "Models/Skybox/Images/Top.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Models/Skybox/Images/Right.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Models/Skybox/Images/Back.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Models/Skybox/Images/Left.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Models/Skybox/Images/Front.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Models/Skybox/Images/Bottom.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Terrain/Textures/Terrain1.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Terrain/Textures/Terrain2.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Terrain/Details/TerrainDetails.bmp", GetNextFreeID()); LoadSkin(m_gameTextureList, "Terrain/Textures/Water1.bmp", GetNextFreeID()); Block* a = new Block(0, 0, 0, 5); AddGameObject(a); a = new Block(30, 0, 0, 5); AddGameObject(a); Player* d = new Player(0, 100,0); AddGameObject(d); } void Block::Draw(){ glPushMatrix(); glTranslatef(m_position.x(), m_position.y(), m_position.z()); glRotatef(m_facingAngle, 0, 1, 0); glScalef(m_size, m_size, m_size); glBegin(GL_LINES); glColor3f(255, 255, 255); glVertex3f(m_boundingRect.left, m_boundingRect.top, m_position.z()); glVertex3f(m_boundingRect.right, m_boundingRect.top, m_position.z()); glVertex3f(m_boundingRect.left, m_boundingRect.bottom, m_position.z()); glVertex3f(m_boundingRect.right, m_boundingRect.bottom, m_position.z()); glVertex3f(m_boundingRect.left, m_boundingRect.top, m_position.z()); glVertex3f(m_boundingRect.left, m_boundingRect.bottom, m_position.z()); glVertex3f(m_boundingRect.right, m_boundingRect.top, m_position.z()); glVertex3f(m_boundingRect.right, m_boundingRect.bottom, m_position.z()); glEnd(); // DrawBox(m_position.x(), m_position.y(), m_position.z(), m_size, m_size, m_size, 8); glPopMatrix(); } void Block::DoCollision(GameObject* obj){ GameObject* t = this;   // I modified this to see for sure that it was causing the mistake. // obj->DoCollision(NULL); // Just revert it back to /* void Block::DoCollision(GameObject* obj){     obj->DoCollision(this);   }   */ }

  Read the article

• Accessing py2exe program over network in Windows 98 throws ImportErrors

  - by darvids0n

  I'm running a py2exe-compiled python program from one server machine on a number of client machines (mapped to a network drive on every machine, say W:). For Windows XP and later machines, have so far had zero problems with Python picking up W:\python23.dll (yes, I'm using Python 2.3.5 for W98 compatibility and all that). It will then use W:\zlib.pyd to decompress W:\library.zip containing all the .pyc files like os and such, which are then imported and the program runs no problems. The issue I'm getting is on some Windows 98 SE machines (note: SOME Windows 98 SE machines, others seem to work with no apparent issues). What happens is, the program runs from W:, the W:\python23.dll is, I assume, found (since I'm getting Python ImportErrors, we'd need to be able to execute a Python import statement), but a couple of things don't work: 1) If W:\library.zip contains the only copy of the .pyc files, I get ZipImportError: can't decompress data; zlib not available (nonsense, considering W:\zlib.pyd IS available and works fine with the XP and higher machines on the same network). 2) If the .pyc files are actually bundled INSIDE the python exe by py2exe, OR put in the same directory as the .exe, OR put into a named subdirectory which is then set as part of the PYTHONPATH variable (e.g W:\pylib), I get ImportError: no module named os (os is the first module imported, before sys and anything else). Come to think of it, sys.path wouldn't be available to search if os was imported before it maybe? I'll try switching the order of those imports but my question still stands: Why is this a sporadic issue, working on some networks but not on others? And how would I force Python to find the files that are bundled inside the very executable I run? I have immediate access to the working Windows 98 SE machine, but I only get access to the non-working one (a customer of mine) every morning before their store opens. Thanks in advance! EDIT: Okay, big step forward. After debugging with PY2EXE_VERBOSE, the problem occurring on the specific W98SE machine is that it's not using the right path syntax when looking for imports. Firstly, it doesn't seem to read the PYTHONPATH environment variable (there may be a py2exe-specific one I'm not aware of, like PY2EXE_VERBOSE). Secondly, it only looks in one place before giving up (if the files are bundled inside the EXE, it looks there. If not, it looks in library.zip). EDIT 2: In fact, according to this, there is a difference between the sys.path in the Python interpreter and that of Py2exe executables. Specifically, sys.path contains only a single entry: the full pathname of the shared code archive. Blah. No fallbacks? Not even the current working directory? I'd try adding W:\ to PATH, but py2exe doesn't conform to any sort of standards for locating system libraries, so it won't work. Now for the interesting bit. The path it tries to load atexit, os, etc. from is: W:\\library.zip\<module>.<ext> Note the single slash after library.zip, but the double slash after the drive letter (someone correct me if this is intended and should work). It looks like if this is a string literal, then since the slash isn't doubled, it's read as an (invalid) escape sequence and the raw character is printed (giving W:\library.zipos.pyd, W:\library.zipos.dll, ... instead of with a slash); if it is NOT a string literal, the double slash might not be normpath'd automatically (as it should be) and so the double slash confuses the module loader. Like I said, I can't just set PYTHONPATH=W:\\library.zip\\ because it ignores that variable. It may be worth using sys.path.append at the start of my program but hard-coding module paths is an absolute LAST resort, especially since the problem occurs in ONE configuration of an outdated OS. Any ideas? I have one, which is to normpath the sys.path.. pity I need os for that. Another is to just append os.getenv('PATH') or os.getenv('PYTHONPATH') to sys.path... again, needing the os module. The site module also fails to initialise, so I can't use a .pth file. I also recently tried the following code at the start of the program: for pth in sys.path: fErr.write(pth) fErr.write(' to ') pth.replace('\\\\','\\') # Fix Windows 98 pathing issues fErr.write(pth) fErr.write('\n') But it can't load linecache.pyc, or anything else for that matter; it can't actually execute those commands from the looks of things. Is there any way to use built-in functionality which doesn't need linecache to modify the sys.path dynamically? Or am I reduced to hard-coding the correct sys.path?

  Read the article

• Approaches for generic, compile-time safe lazy-load methods

  - by Aaronaught

  Suppose I have created a wrapper class like the following: public class Foo : IFoo { private readonly IFoo innerFoo; public Foo(IFoo innerFoo) { this.innerFoo = innerFoo; } public int? Bar { get; set; } public int? Baz { get; set; } } The idea here is that the innerFoo might wrap data-access methods or something similarly expensive, and I only want its GetBar and GetBaz methods to be invoked once. So I want to create another wrapper around it, which will save the values obtained on the first run. It's simple enough to do this, of course: int IFoo.GetBar() { if ((Bar == null) && (innerFoo != null)) Bar = innerFoo.GetBar(); return Bar ?? 0; } int IFoo.GetBaz() { if ((Baz == null) && (innerFoo != null)) Baz = innerFoo.GetBaz(); return Baz ?? 0; } But it gets pretty repetitive if I'm doing this with 10 different properties and 30 different wrappers. So I figured, hey, let's make this generic: T LazyLoad<T>(ref T prop, Func<IFoo, T> loader) { if ((prop == null) && (innerFoo != null)) prop = loader(innerFoo); return prop; } Which almost gets me where I want, but not quite, because you can't ref an auto-property (or any property at all). In other words, I can't write this: int IFoo.GetBar() { return LazyLoad(ref Bar, f => f.GetBar()); // <--- Won't compile } Instead, I'd have to change Bar to have an explicit backing field and write explicit getters and setters. Which is fine, except for the fact that I end up writing even more redundant code than I was writing in the first place. Then I considered the possibility of using expression trees: T LazyLoad<T>(Expression<Func<T>> propExpr, Func<IFoo, T> loader) { var memberExpression = propExpr.Body as MemberExpression; if (memberExpression != null) { // Use Reflection to inspect/set the property } } This plays nice with refactoring - it'll work great if I do this: return LazyLoad(f => f.Bar, f => f.GetBar()); But it's not actually safe, because someone less clever (i.e. myself in 3 days from now when I inevitably forget how this is implemented internally) could decide to write this instead: return LazyLoad(f => 3, f => f.GetBar()); Which is either going to crash or result in unexpected/undefined behaviour, depending on how defensively I write the LazyLoad method. So I don't really like this approach either, because it leads to the possibility of runtime errors which would have been prevented in the first attempt. It also relies on Reflection, which feels a little dirty here, even though this code is admittedly not performance-sensitive. Now I could also decide to go all-out and use DynamicProxy to do method interception and not have to write any code, and in fact I already do this in some applications. But this code is residing in a core library which many other assemblies depend on, and it seems horribly wrong to be introducing this kind of complexity at such a low level. Separating the interceptor-based implementation from the IFoo interface by putting it into its own assembly doesn't really help; the fact is that this very class is still going to be used all over the place, must be used, so this isn't one of those problems that could be trivially solved with a little DI magic. The last option I've already thought of would be to have a method like: T LazyLoad<T>(Func<T> getter, Action<T> setter, Func<IFoo, T> loader) { ... } This option is very "meh" as well - it avoids Reflection but is still error-prone, and it doesn't really reduce the repetition that much. It's almost as bad as having to write explicit getters and setters for each property. Maybe I'm just being incredibly nit-picky, but this application is still in its early stages, and it's going to grow substantially over time, and I really want to keep the code squeaky-clean. Bottom line: I'm at an impasse, looking for other ideas. Question: Is there any way to clean up the lazy-loading code at the top, such that the implementation will: Guarantee compile-time safety, like the ref version; Actually reduce the amount of code repetition, like the Expression version; and Not take on any significant additional dependencies? In other words, is there a way to do this just using regular C# language features and possibly a few small helper classes? Or am I just going to have to accept that there's a trade-off here and strike one of the above requirements from the list?

  Read the article

• [ebp + 6] instead of +8 in a JIT compiler

  - by David Titarenco

  I'm implementing a simplistic JIT compiler in a VM I'm writing for fun (mostly to learn more about language design) and I'm getting some weird behavior, maybe someone can tell me why. First I define a JIT "prototype" both for C and C++: #ifdef __cplusplus typedef void* (*_JIT_METHOD) (...); #else typedef (*_JIT_METHOD) (); #endif I have a compile() function that will compile stuff into ASM and stick it somewhere in memory: void* compile (void* something) { // grab some memory unsigned char* buffer = (unsigned char*) malloc (1024); // xor eax, eax // inc eax // inc eax // inc eax // ret -> eax should be 3 /* WORKS! buffer[0] = 0x67; buffer[1] = 0x31; buffer[2] = 0xC0; buffer[3] = 0x67; buffer[4] = 0x40; buffer[5] = 0x67; buffer[6] = 0x40; buffer[7] = 0x67; buffer[8] = 0x40; buffer[9] = 0xC3; */ // xor eax, eax // mov eax, 9 // ret 4 -> eax should be 9 /* WORKS! buffer[0] = 0x67; buffer[1] = 0x31; buffer[2] = 0xC0; buffer[3] = 0x67; buffer[4] = 0xB8; buffer[5] = 0x09; buffer[6] = 0x00; buffer[7] = 0x00; buffer[8] = 0x00; buffer[9] = 0xC3; */ // push ebp // mov ebp, esp // mov eax, [ebp + 6] ; wtf? shouldn't this be [ebp + 8]!? // mov esp, ebp // pop ebp // ret -> eax should be the first value sent to the function /* WORKS! */ buffer[0] = 0x66; buffer[1] = 0x55; buffer[2] = 0x66; buffer[3] = 0x89; buffer[4] = 0xE5; buffer[5] = 0x66; buffer[6] = 0x66; buffer[7] = 0x8B; buffer[8] = 0x45; buffer[9] = 0x06; buffer[10] = 0x66; buffer[11] = 0x89; buffer[12] = 0xEC; buffer[13] = 0x66; buffer[14] = 0x5D; buffer[15] = 0xC3; // mov eax, 5 // add eax, ecx // ret -> eax should be 50 /* WORKS! buffer[0] = 0x67; buffer[1] = 0xB8; buffer[2] = 0x05; buffer[3] = 0x00; buffer[4] = 0x00; buffer[5] = 0x00; buffer[6] = 0x66; buffer[7] = 0x01; buffer[8] = 0xC8; buffer[9] = 0xC3; */ return buffer; } And finally I have the main chunk of the program: void main (int argc, char **args) { DWORD oldProtect = (DWORD) NULL; int i = 667, j = 1, k = 5, l = 0; // generate some arbitrary function _JIT_METHOD someFunc = (_JIT_METHOD) compile(NULL); // windows only #if defined _WIN64 || defined _WIN32 // set memory permissions and flush CPU code cache VirtualProtect(someFunc,1024,PAGE_EXECUTE_READWRITE, &oldProtect); FlushInstructionCache(GetCurrentProcess(), someFunc, 1024); #endif // this asm just for some debugging/testing purposes __asm mov ecx, i // run compiled function (from wherever *someFunc is pointing to) l = (int)someFunc(i, k); // did it work? printf("result: %d", l); free (someFunc); _getch(); } As you can see, the compile() function has a couple of tests I ran to make sure I get expected results, and pretty much everything works but I have a question... On most tutorials or documentation resources, to get the first value of a function passed (in the case of ints) you do [ebp+8], the second [ebp+12] and so forth. For some reason, I have to do [ebp+6] then [ebp+10] and so forth. Could anyone tell me why?

  Read the article

• ffmpeg-php permission denied on localhost

  - by user572271

  Hello, I am very new to php. I recently setup php on my mac and I am trying to setup ffmpeg-php to convert various videos to flv or other formats as desired. I used this tutorial FFmpeg Mac Installation and I got ffmpeg to work using the terminal, however, when I try to encode a movie using php I get an error. In my apache error_log file it says permission denied next to the flv file (shown below). FFmpeg version 0.6, Copyright (c) 2000-2010 the FFmpeg developers built on Dec 30 2010 08:36:24 with gcc 4.2.1 (Apple Inc. build 5646) (dot 1) configuration: --prefix=/usr/local --enable-shared --disable-mmx --enable-libmp3lame --enable-gpl --enable-libfaad --enable-zlib --enable-libvorbis --enable-libfaac --enable-nonfree libavutil 50.15. 1 / 50.15. 1 libavcodec 52.72. 2 / 52.72. 2 libavformat 52.64. 2 / 52.64. 2 libavdevice 52. 2. 0 / 52. 2. 0 libswscale 0.11. 0 / 0.11. 0 Seems stream 1 codec frame rate differs from container frame rate: 1200.00 (1200/1) - 30.00 (30/1) Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/myApple/Sites/AdHere/test.mov': Metadata: major_brand : qt minor_version : 537199360 compatible_brands: qt Duration: 00:00:02.04, start: 0.000000, bitrate: 1109 kb/s Stream #0.0(eng): Audio: aac, 44100 Hz, stereo, s16, 97 kb/s Stream #0.1(eng): Video: h264, yuv420p, 640x480, 1027 kb/s, 30.15 fps, 30 tbr, 600 tbn, 1200 tbc /Users/myApple/Sites/AdHere/movteststuff.flv: Permission denied I have no idea what the problem is. I am using the following php code: <?php extension_loaded('ffmpeg') or die('Error in loading ffmpeg'); $ffmpegInstance = new ffmpeg_movie('test.AVI'); echo "getDuration: " . $ffmpegInstance->getDuration() . "<br>getFrameCount: " . $ffmpegInstance->getFrameCount() . "<br>getFrameRate: " . $ffmpegInstance->getFrameRate() . "<br>getFilename: " . $ffmpegInstance->getFilename() . "<br>getComment: " . $ffmpegInstance->getComment() . "<br>getTitle: " . $ffmpegInstance->getTitle() . "<br>getAuthor: " . $ffmpegInstance->getAuthor() . "<br>getCopyright: " . $ffmpegInstance->getCopyright() . "<br>getArtist: " . $ffmpegInstance->getArtist() . "<br>getGenre: " . $ffmpegInstance->getGenre() . "<br>getTrackNumber: " . $ffmpegInstance->getTrackNumber() . "<br>getYear: " . $ffmpegInstance->getYear() . "<br>getFrameHeight: " . $ffmpegInstance->getFrameHeight() . "<br>getFrameWidth: " . $ffmpegInstance->getFrameWidth() . "<br>getPixelFormat: " . $ffmpegInstance->getPixelFormat() . "<br>getBitRate: " . $ffmpegInstance->getBitRate() . "<br>getVideoBitRate: " . $ffmpegInstance->getVideoBitRate() . "<br>getAudioBitRate: " . $ffmpegInstance->getAudioBitRate() . "<br>getAudioSampleRate: " . $ffmpegInstance->getAudioSampleRate() . "<br>getVideoCodec: " . $ffmpegInstance->getVideoCodec() . "<br>getAudioCodec: " . $ffmpegInstance->getAudioCodec() . "<br>getAudioChannels: " . $ffmpegInstance->getAudioChannels() . "<br>hasAudio: " . $ffmpegInstance->hasAudio(); exec('ffmpeg -i /Users/myApple/Sites/AdHere/test.mov /Users/myApple/Sites/AdHere/movteststuff.flv'); ?> I am able to see various parameters like filename, frameheight, framewidth, which leads me to believe that ffmpeg-php is kind of working, but maybe I am just doing something wrong in the exec() command. Anyone have any ideas. I have been struggling with setting up ffmpeg for quite some time now. Thanks! -Jon

  Read the article

• collision with moving objects

  - by blacksheep

  tried to write a collision with the moving "floats" but did not succeed. maybe wrong place of the "collision" code? thanx 4 help! // // FruitsView.m // import "FruitsView.h" import "Constants.h" import "Utilities.h" define kFloat1Speed 0.15 define kFloat2Speed 0.3 define kFloat3Speed 0.2 @interface FruitsView (Private) - (void) stopTimer; @end @implementation FruitsView @synthesize apple, float1, float2, float3, posFloat1, posFloat2, posFloat3; -(void)onTimer { float1.center = CGPointMake(float1.center.x+posFloat1.x,float1.cen ter.y+posFloat1.y); if(float1.center.x 380 || float1.center.x < -60) posFloat1.x = -posFloat1.x; if(float1.center.y 100 || float1.center.y < -40) posFloat1.y = -posFloat1.y; float2.center = CGPointMake(float2.center.x+posFloat2.x,float2.cen ter.y+posFloat2.y); if(float2.center.x 380 || float2.center.x < -50) posFloat2.x = -posFloat2.x; if(float2.center.y 150 || float2.center.y < -30) posFloat2.y = -posFloat2.y; float3.center = CGPointMake(float3.center.x+posFloat3.x,float3.cen ter.y+posFloat3.y); if(float3.center.x 380 || float3.center.x < -70) posFloat3.x = -posFloat3.x; if(float3.center.y 100 || float3.center.y < -20) posFloat3.y = -posFloat3.y; if(CGRectIntersectsRect(apple.frame,float1.frame)) { if(apple.center.y float1.center.y) { posApple.y = -posApple.y; } } if(CGRectIntersectsRect(apple.frame,float2.frame)) { if(apple.center.y float2.center.y) { posFloat2.y = -posFloat2.y; } } if(CGRectIntersectsRect(apple.frame,float3.frame)) { if(apple.center.y float3.center.y) { posFloat3.y = -posFloat3.y; } } } pragma mark Initialisation/destruction (void)awakeFromNib { [NSTimer scheduledTimerWithTimeInterval:0.0001 target:self selector:@selector(onTimer) userInfo:nil repeats:YES]; posFloat1 = CGPointMake(kFloat1Speed, 0); posFloat2 = CGPointMake(kFloat2Speed, 0); posFloat3 = CGPointMake(kFloat3Speed, 0); timer = nil; modeLock = lockNotYetChosen; defaultSize = self.bounds.size.width; modal = self.tag; [[UIAccelerometer sharedAccelerometer] setDelegate:self]; [UIView beginAnimations:nil context:nil]; [UIView setAnimationRepeatCount:1]; eadbea.transform = CGAffineTransformMakeScale(0.5,0.5); [UIView commitAnimations]; [UIView beginAnimations:nil context:nil]; [UIView setAnimationRepeatCount:1]; apple.transform = CGAffineTransformMakeScale(0.5,0.5); [UIView commitAnimations]; } pragma mark Background animation processing (void) startTimer { if (!timer) { timer = [[NSTimer scheduledTimerWithTimeInterval:1.0/60.0 target:self selector:@selector(timerTick:) userInfo:nil repeats:YES] retain]; } } (void) stopTimer { [timer invalidate]; [timer release]; timer = nil; } (void) check:(CGPoint*)position delta:(CGSize*)delta halfSize:(CGSize)halfSize forBouncingAgainst:(CGSize)containerSize { if ((position-x - halfSize.width)<0) { delta-width = fabsf(delta-width)*BOUNCE_DAMPING; position-x = halfSize.width; } if ((position-x + halfSize.width)containerSize.width) { delta-width = fabsf(delta-width)*-BOUNCE_DAMPING; position-x = containerSize.width - halfSize.width; } if ((position-y - halfSize.height)<0) { delta-height = fabsf(delta-height)*BOUNCE_DAMPING; position-y = halfSize.height; } if ((position-y + halfSize.height)containerSize.height) { delta-height = fabsf(delta-height)*-BOUNCE_DAMPING; position-y = containerSize.height - halfSize.height; } } (void) timerTick: (NSTimer*)timer { dragDelta = CGSizeScale(dragDelta, INERTIAL_DAMPING); if ((fabsf(dragDelta.width)DELTA_ZERO_THRESHOLD) || (fabsf(dragDelta.height)DELTA_ZERO_THRESHOLD)) { CGPoint ctr = CGPointApplyDelta(self.center, dragDelta); CGSize halfSize = CGSizeMake(self.bounds.size.width/4, self.bounds.size.height/4); [self check:&ctr delta:&dragDelta halfSize:halfSize forBouncingAgainst:self.superview.bounds.size]; self.center = ctr; } else { [self stopTimer]; } } pragma mark Input Handling (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent )event { NSSet allTouches = [event touchesForView:self]; if ([allTouches count]==1) { if (modeLocklockNotYetChosen) return; UITouch* anyTouch = [touches anyObject]; lastMove = anyTouch.timestamp; CGPoint now = [anyTouch locationInView: self.superview]; CGPoint then = [anyTouch previousLocationInView: self.superview]; dragDelta = CGPointDelta(now, then); self.center = CGPointApplyDelta(self.center, dragDelta); [self stopTimer]; } } (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { NSSet* allTouches = [event touchesForView:self]; if ([touches count]==[allTouches count]) { modeLock = lockNotYetChosen; if ((event.timestamp - lastMove) MOVEMENT_PAUSE_THRESHOLD) return; if ((fabsf(dragDelta.width)INERTIA_THRESHOLD) || (fabsf(dragDelta.height)INERTIA_THRESHOLD)) { [self startTimer]; } } } (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event { modeLock = lockNotYetChosen; [self stopTimer]; } (void)dealloc { [float1 release]; [float2 release]; [float3 release]; [apple release]; [bear_head release]; [self stopTimer]; [super dealloc]; } @end

  Read the article

• Reverse engineering windows mobile live search CellID location awareness protocol (yikes)...

  - by Jean-Charles

  I wasn't sure of how to form the question so I apologize if the title is misleading. Additionally, you may want to get some coffee and take a seat for this one ... It's long. Basically, I'm trying to reverse engineer the protocol used by the Windows Mobile Live Search application to get location based on cellID. Before I go on, I am aware of other open source services (such as OpenCellID) but this is more for the sake of education and a bit for redundancy. According to the packets I captured, a POST request is made to ... mobile.search.live.com/positionlookupservice_1/service.aspx ... with a few specific headers (agent, content-length, etc) and no body. Once this goes through, the server sends back a 100-Continue response. At this point, the application submits this data (I chopped off the packet header): 00 00 00 01 00 00 00 05 55 54 ........UT 46 2d 38 05 65 6e 2d 55 53 05 65 6e 2d 55 53 01 F-8.en-US.en-US. 06 44 65 76 69 63 65 05 64 75 6d 6d 79 01 06 02 .Device.dummy... 50 4c 08 0e 52 65 76 65 72 73 65 47 65 6f 63 6f PL..ReverseGeoco 64 65 01 07 0b 47 50 53 43 68 69 70 49 6e 66 6f de...GPSChipInfo 01 20 06 09 43 65 6c 6c 54 6f 77 65 72 06 03 43 . ..CellTower..C 47 49 08 03 4d 43 43 b6 02 07 03 4d 4e 43 03 34 GI..MCC....MNC.4 31 30 08 03 4c 41 43 cf 36 08 02 43 49 fd 01 00 10..LAC.6..CI... 00 00 00 ... And receives this in response (packet and HTTP response headers chopped): 00 00 00 01 00 00 00 00 01 06 02 50 4c ...........PL 06 08 4c 6f 63 61 6c 69 74 79 06 08 4c 6f 63 61 ..Locality..Loca 74 69 6f 6e 07 03 4c 61 74 09 34 32 2e 33 37 35 tion..Lat.42.375 36 32 31 07 04 4c 6f 6e 67 0a 2d 37 31 2e 31 35 621..Long.-71.15 38 39 33 38 00 07 06 52 61 64 69 75 73 09 32 30 8938...Radius.20 30 30 2e 30 30 30 30 00 42 07 0c 4c 6f 63 61 6c 00.0000.B..Local 69 74 79 4e 61 6d 65 09 57 61 74 65 72 74 6f 77 ityName.Watertow 6e 07 16 41 64 6d 69 6e 69 73 74 72 61 74 69 76 n..Administrativ 65 41 72 65 61 4e 61 6d 65 0d 4d 61 73 73 61 63 eAreaName.Massac 68 75 73 65 74 74 73 07 10 50 6f 73 74 61 6c 43 husetts..PostalC 6f 64 65 4e 75 6d 62 65 72 05 30 32 34 37 32 07 odeNumber.02472. 0b 43 6f 75 6e 74 72 79 4e 61 6d 65 0d 55 6e 69 .CountryName.Uni 74 65 64 20 53 74 61 74 65 73 00 00 00 ted States... Now, here is what I've determined so far: All strings are prepended with one byte that is the decimal equivalent of their length. There seem to be three different casts that are used throughout the request and response. They show up as one byte before the length byte. I've concluded that the three types map out as follows: 0x06 - parent element (subsequent values are children, closed with 0x00) 0x07 - string 0x08 - int? Based on these determinations, here is what the request and response look like in a more readable manner (values surrounded by brackets denote length and values surrounded by parenthesis denote a cast): \0x00\0x00\0x00\0x01\0x00\0x00\0x00 [5]UTF-8 [5]en-US [5]en-US \0x01 [6]Device [5]dummy \0x01 (6)[2]PL (8)[14]ReverseGeocode\0x01 (7)[11]GPSChipInfo[1]\0x20 (6)[9]CellTower (6)[3]CGI (8)[3]MCC\0xB6\0x02 //310 (7)[3]MNC[3]410 //410 (8)[3]LAC\0xCF\0x36 //6991 (8)[2]CI\0xFD\0x01 //259 \0x00 \0x00 \0x00 \0x00 and.. \0x00\0x00\0x00\0x01\0x00\0x00\0x00 \0x00\0x01 (6)[2]PL (6)[8]Locality (6)[8]Location (7)[3]Lat[9]42.375621 (7)[4]Long[10]-71.158938 \0x00 (7)[6]Radius[9]2000.0000 \0x00 \0x42 //"B" ... Has to do with GSM (7)[12]LocalityName[9]Watertown (7)[22]AdministrativeAreaName[13]Massachusetts (7)[16]PostalCodeNumber[5]02472 (7)[11]CountryName[13]United States \0x00 \0x00\0x00 My analysis seems to work out pretty well except for a few things: The 0x01s throughout confuse me ... At first I thought they were some sort of base level element terminators but I'm not certain. I'm not sure the 7-byte header is, in fact, a seven byte header. I wonder if it's maybe 4 bytes and that the three remaining 0x00s are of some other significance. The trailing 0x00s. Why is it that there is only one on the request but two on the response? The type 8 cast mentioned above ... I can't seem to figure out how those values are being encoded. I added comments to those lines with what the values should correspond to. Any advice on these four points will be greatly appreciated. And yes, these packets were captured in Watertown, MA. :)

  Read the article

• Strange: Planner takes decision with lower cost, but (very) query long runtime

  - by S38

  Facts: PGSQL 8.4.2, Linux I make use of table inheritance Each Table contains 3 million rows Indexes on joining columns are set Table statistics (analyze, vacuum analyze) are up-to-date Only used table is "node" with varios partitioned sub-tables Recursive query (pg = 8.4) Now here is the explained query: WITH RECURSIVE rows AS ( SELECT * FROM ( SELECT r.id, r.set, r.parent, r.masterid FROM d_storage.node_dataset r WHERE masterid = 3533933 ) q UNION ALL SELECT * FROM ( SELECT c.id, c.set, c.parent, r.masterid FROM rows r JOIN a_storage.node c ON c.parent = r.id ) q ) SELECT r.masterid, r.id AS nodeid FROM rows r QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------- CTE Scan on rows r (cost=2742105.92..2862119.94 rows=6000701 width=16) (actual time=0.033..172111.204 rows=4 loops=1) CTE rows -> Recursive Union (cost=0.00..2742105.92 rows=6000701 width=28) (actual time=0.029..172111.183 rows=4 loops=1) -> Index Scan using node_dataset_masterid on node_dataset r (cost=0.00..8.60 rows=1 width=28) (actual time=0.025..0.027 rows=1 loops=1) Index Cond: (masterid = 3533933) -> Hash Join (cost=0.33..262208.33 rows=600070 width=28) (actual time=40628.371..57370.361 rows=1 loops=3) Hash Cond: (c.parent = r.id) -> Append (cost=0.00..211202.04 rows=12001404 width=20) (actual time=0.011..46365.669 rows=12000004 loops=3) -> Seq Scan on node c (cost=0.00..24.00 rows=1400 width=20) (actual time=0.002..0.002 rows=0 loops=3) -> Seq Scan on node_dataset c (cost=0.00..55001.01 rows=3000001 width=20) (actual time=0.007..3426.593 rows=3000001 loops=3) -> Seq Scan on node_stammdaten c (cost=0.00..52059.01 rows=3000001 width=20) (actual time=0.008..9049.189 rows=3000001 loops=3) -> Seq Scan on node_stammdaten_adresse c (cost=0.00..52059.01 rows=3000001 width=20) (actual time=3.455..8381.725 rows=3000001 loops=3) -> Seq Scan on node_testdaten c (cost=0.00..52059.01 rows=3000001 width=20) (actual time=1.810..5259.178 rows=3000001 loops=3) -> Hash (cost=0.20..0.20 rows=10 width=16) (actual time=0.010..0.010 rows=1 loops=3) -> WorkTable Scan on rows r (cost=0.00..0.20 rows=10 width=16) (actual time=0.002..0.004 rows=1 loops=3) Total runtime: 172111.371 ms (16 rows) (END) So far so bad, the planner decides to choose hash joins (good) but no indexes (bad). Now after doing the following: SET enable_hashjoins TO false; The explained query looks like that: QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- CTE Scan on rows r (cost=15198247.00..15318261.02 rows=6000701 width=16) (actual time=0.038..49.221 rows=4 loops=1) CTE rows -> Recursive Union (cost=0.00..15198247.00 rows=6000701 width=28) (actual time=0.032..49.201 rows=4 loops=1) -> Index Scan using node_dataset_masterid on node_dataset r (cost=0.00..8.60 rows=1 width=28) (actual time=0.028..0.031 rows=1 loops=1) Index Cond: (masterid = 3533933) -> Nested Loop (cost=0.00..1507822.44 rows=600070 width=28) (actual time=10.384..16.382 rows=1 loops=3) Join Filter: (r.id = c.parent) -> WorkTable Scan on rows r (cost=0.00..0.20 rows=10 width=16) (actual time=0.001..0.003 rows=1 loops=3) -> Append (cost=0.00..113264.67 rows=3001404 width=20) (actual time=8.546..12.268 rows=1 loops=4) -> Seq Scan on node c (cost=0.00..24.00 rows=1400 width=20) (actual time=0.001..0.001 rows=0 loops=4) -> Bitmap Heap Scan on node_dataset c (cost=58213.87..113214.88 rows=3000001 width=20) (actual time=1.906..1.906 rows=0 loops=4) Recheck Cond: (c.parent = r.id) -> Bitmap Index Scan on node_dataset_parent (cost=0.00..57463.87 rows=3000001 width=0) (actual time=1.903..1.903 rows=0 loops=4) Index Cond: (c.parent = r.id) -> Index Scan using node_stammdaten_parent on node_stammdaten c (cost=0.00..8.60 rows=1 width=20) (actual time=3.272..3.273 rows=0 loops=4) Index Cond: (c.parent = r.id) -> Index Scan using node_stammdaten_adresse_parent on node_stammdaten_adresse c (cost=0.00..8.60 rows=1 width=20) (actual time=4.333..4.333 rows=0 loops=4) Index Cond: (c.parent = r.id) -> Index Scan using node_testdaten_parent on node_testdaten c (cost=0.00..8.60 rows=1 width=20) (actual time=2.745..2.746 rows=0 loops=4) Index Cond: (c.parent = r.id) Total runtime: 49.349 ms (21 rows) (END) - incredibly faster, because indexes were used. Notice: Cost of the second query ist somewhat higher than for the first query. So the main question is: Why does the planner make the first decision, instead of the second? Also interesing: Via SET enable_seqscan TO false; i temp. disabled seq scans. Than the planner used indexes and hash joins, and the query still was slow. So the problem seems to be the hash join. Maybe someone can help in this confusing situation? thx, R.

  Read the article

• What statistics can be maintained for a set of numerical data without iterating?

  - by Dan Tao

  Update Just for future reference, I'm going to list all of the statistics that I'm aware of that can be maintained in a rolling collection, recalculated as an O(1) operation on every addition/removal (this is really how I should've worded the question from the beginning): Obvious Count Sum Mean Max* Min* Median** Less Obvious Variance Standard Deviation Skewness Kurtosis Mode*** Weighted Average Weighted Moving Average**** OK, so to put it more accurately: these are not "all" of the statistics I'm aware of. They're just the ones that I can remember off the top of my head right now. *Can be recalculated in O(1) for additions only, or for additions and removals if the collection is sorted (but in this case, insertion is not O(1)). Removals potentially incur an O(n) recalculation for non-sorted collections. **Recalculated in O(1) for a sorted, indexed collection only. ***Requires a fairly complex data structure to recalculate in O(1). ****This can certainly be achieved in O(1) for additions and removals when the weights are assigned in a linearly descending fashion. In other scenarios, I'm not sure. Original Question Say I maintain a collection of numerical data -- let's say, just a bunch of numbers. For this data, there are loads of calculated values that might be of interest; one example would be the sum. To get the sum of all this data, I could... Option 1: Iterate through the collection, adding all the values: double sum = 0.0; for (int i = 0; i < values.Count; i++) sum += values[i]; Option 2: Maintain the sum, eliminating the need to ever iterate over the collection just to find the sum: void Add(double value) { values.Add(value); sum += value; } void Remove(double value) { values.Remove(value); sum -= value; } EDIT: To put this question in more relatable terms, let's compare the two options above to a (sort of) real-world situation: Suppose I start listing numbers out loud and ask you to keep them in your head. I start by saying, "11, 16, 13, 12." If you've just been remembering the numbers themselves and nothing more, and then I say, "What's the sum?", you'd have to think to yourself, "OK, what's 11 + 16 + 13 + 12?" before responding, "52." If, on the other hand, you had been keeping track of the sum yourself while I was listing the numbers (i.e., when I said, "11" you thought "11", when I said "16", you thought, "27," and so on), you could answer "52" right away. Then if I say, "OK, now forget the number 16," if you've been keeping track of the sum inside your head you can simply take 16 away from 52 and know that the new sum is 36, rather than taking 16 off the list and them summing up 11 + 13 + 12. So my question is, what other calculations, other than the obvious ones like sum and average, are like this? SECOND EDIT: As an arbitrary example of a statistic that (I'm almost certain) does require iteration -- and therefore cannot be maintained as simply as a sum or average -- consider if I asked you, "how many numbers in this collection are divisible by the min?" Let's say the numbers are 5, 15, 19, 20, 21, 25, and 30. The min of this set is 5, which divides into 5, 15, 20, 25, and 30 (but not 19 or 21), so the answer is 5. Now if I remove 5 from the collection and ask the same question, the answer is now 2, since only 15 and 30 are divisible by the new min of 15; but, as far as I can tell, you cannot know this without going through the collection again. So I think this gets to the heart of my question: if we can divide kinds of statistics into these categories, those that are maintainable (my own term, maybe there's a more official one somewhere) versus those that require iteration to compute any time a collection is changed, what are all the maintainable ones? What I am asking about is not strictly the same as an online algorithm (though I sincerely thank those of you who introduced me to that concept). An online algorithm can begin its work without having even seen all of the input data; the maintainable statistics I am seeking will certainly have seen all the data, they just don't need to reiterate through it over and over again whenever it changes.

  Read the article

• Logging with log4j on tomcat jruby-rack for a Rails 3 application

  - by John

  I just spent the better part of 3 hours trying to get my Rails application logging with Log4j. I've finally got it working, but I'm not sure if what I did is correct. I tried various methods to no avail until my various last attempt. So I'm really looking for some validation here, perhaps some pointers and tips as well -- anything would be appreciated to be honest. I've summarized all my feeble methods into three attempts below. I'm hoping for some enlightenment on where I went wrong with each attempt -- even if it means I get ripped up. Thanks for the help in advance! System Specs Rails 3.0 Windows Server 2008 Log4j 1.2 Tomact 6.0.29 Java 6 Attempt 1 - Configured Tomcat to Use Log4J I basically followed the guide on the Apache Tomcat website here. The steps are: Create a log4j.properties file in $CATALINA_HOME/lib Download and copy the log4j-x.y.z.jar into $CATALINA_HOME/lib Replace $CATALINA_HOME/bin/tomcat-juli.jar with the tomcat-juli.jar from the Apache Tomcat Extras folder Copy tomcat-juli-adapters.jar from the Apache Tomcat Extras folder into $CATALINA_HOME/lib Delete $CATALINA_BASE/conf/logging.properties Start Tomcat (as a service) Expected Results According to the Guide I should have seen a tomcat.log file in my $CATALINA_BASE/logs folder. Actual Results No tomcat.log Saw three of the standard logs instead jakarta_service_20101231.log stderr_20101231.log stdout_20101231.log Question Shouldn't I have at least seen a tomcat.log file? Attempt 2 - Use default Tomcat logging (commons-logging) Reverted all the changes from the previous setup Modified $CATALINA_BASE/conf/logging.properties by doing the following: Adding a setting for my application in the handlers line: 5rails3.org.apache.juli.FileHandler Adding Handler specific properties 5rails3.org.apache.juli.FileHandler.level = FINE 5rails3.org.apache.juli.FileHandler.directory = ${catalina.base}/logs 5rails3.org.apache.juli.FileHandler.prefix = rails3. Adding Facility specific properties org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/rails3].level = INFO org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/rails3].handlers = 4host-manager.org.apache.juli.FileHandler Modified my web.xml by adding the following context parameter as per the Logging section of the jruby-rack readme (I also modified my warbler.rb accordingly, but I did opted to change the web.xml directly to test things faster). <context-param> <param-name>jruby.rack.logging</param-name> <param-value>commons_logging</param-value> </context-param> Restarted Tomcat Results A log file was created (rails3.log), however there was no log information in the file. Attempt 2A - Use Log4j with existing set up I decided to go Log4j another whirl with this new web.xml setting. Copied the log4j.jar into my WEB-INF/lib folder Created a log4j.properties file and put it into WEB-INF/classes log4j.rootLogger=INFO, R log4j.logger.javax.servlet=DEBUG log4j.appender.R=org.apache.log4j.RollingFileAppender log4j.appender.R.File=${catalina.base}/logs/rails3.log log4j.appender.R.MaxFileSize=5036KB log4j.appender.R.MaxBackupIndex=4 log4j.appender.R.layout=org.apache.log4j.PatternLayout log4j.appender.R.layout.ConversionPattern=%d{dd MMM yyyy HH:mm:ss} [%t] %-5p %c %x - %m%n Restarted Tomcat Results Same as Attempt 2 NOTE: I used log4j.logger.javax.servlet=DEBUG because I read in the jruby-rack README that all logging output is automatically redirected to the javax.servlet.ServletContext#log method. So I though this would capture it. I was obviously wrong. Question Why didn't this work? Isn't Log4J using the commons_logging API? Attempt 3 - Tried out slf4j (WORKED) A bit uncertain as to why Attempt 2A didn't work, I thought to myself, maybe I can't use commons_logging for the jruby.rack.logging parameter because it's probably not using commons_logging API... (but I was still not sure). I saw slf4j as an option. I have never heard of it and by stroke of luck, I decided to look up what it is. After reading briefly about what it does, I thought it was good of a shot as any and decided to try it out following the instructions here. Continuing from the setup of Attempt 2A: Copied slf4j-api-1.6.1.jar and slf4j-simple-1.6.1.jar into my WEB-INF/lib folder I also copied slf4j-log4j12-1.6.1.jar into my WEB-INF/lib folder Restarted Tomcat And VIOLA! I now have logging information going into my rails3.log file. So the big question is: WTF? Even though logging seems to be working now, I'm really not sure if I did this right. So like I said earlier, I'm really looking for some validation more or less. I'd also appreciate any pointers/tips/advice if you have any. Thanks!

  Read the article

• How do you control what your C compiler Optimizes?

  - by Jordan S

  I am writing the firmware for an embedded device in C using the Silicon Labs IDE and the SDCC compiler. The device architecture is based on the 8051 family. The function in question is shown below. The function is used to set the ports on my MCU to drive a stepper motor. It gets called in by an interrupt handler. The big switch statement just sets the ports to the proper value for the next motor step. The bottom part of the function looks at an input from a hall effect sensor and a number of steps moved in order to detect if the motor has stalled. The problem is, for some reason the second IF statement that looks like this if (StallDetector > (GapSize + 20)) { HandleStallEvent(); } always seems to get optimized out. If I try to put a breakpoint at the HandleStallEvent() call the IDE gives me a message saying "No Address Correlation to this line number". I am not really good enough at reading assembly to tell what it is doing but I have pasted a snippet from the asm output below. Any help would be much appreciated. void OperateStepper(void) { //static bit LastHomeMagState = HomeSensor; static bit LastPosMagState = PosSensor; if(PulseMotor) { if(MoveDirection == 1) // Go clockwise { switch(STEPPER_POSITION) { case 'A': STEPPER_POSITION = 'B'; P1 = 0xFD; break; case 'B': STEPPER_POSITION = 'C'; P1 = 0xFF; break; case 'C': STEPPER_POSITION = 'D'; P1 = 0xFE; break; case 'D': STEPPER_POSITION = 'A'; P1 = 0xFC; break; default: STEPPER_POSITION = 'A'; P1 = 0xFC; } //end switch } else // Go CounterClockwise { switch(STEPPER_POSITION) { case 'A': STEPPER_POSITION = 'D'; P1 = 0xFE; break; case 'B': STEPPER_POSITION = 'A'; P1 = 0xFC; break; case 'C': STEPPER_POSITION = 'B'; P1 = 0xFD; break; case 'D': STEPPER_POSITION = 'C'; P1 = 0xFF; break; default: STEPPER_POSITION = 'A'; P1 = 0xFE; } //end switch } //end else MotorSteps++; StallDetector++; if(PosSensor != LastPosMagState) { StallDetector = 0; LastPosMagState = PosSensor; } else { if (PosSensor == ON) { if (StallDetector > (MagnetSize + 20)) { HandleStallEvent(); } } else if (PosSensor == OFF) { if (StallDetector > (GapSize + 20)) { HandleStallEvent(); } } } } //end if PulseMotor } ... and the asm output for the the bottom part of this function... ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:653: if(PosSensor != LastPosMagState) mov c,_P1_4 jb _OperateStepper_LastPosMagState_1_1,00158$ cpl c 00158$: jc 00126$ C$MotionControl.c$655$3$7 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:655: StallDetector = 0; clr a mov _StallDetector,a mov (_StallDetector + 1),a C$MotionControl.c$657$3$7 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:657: LastPosMagState = PosSensor; mov c,_P1_4 mov _OperateStepper_LastPosMagState_1_1,c ret 00126$: C$MotionControl.c$661$2$8 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:661: if (PosSensor == ON) jb _P1_4,00123$ C$MotionControl.c$663$4$9 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:663: if (StallDetector > (MagnetSize + 20)) mov a,_MagnetSize mov r2,a rlc a subb a,acc mov r3,a mov a,#0x14 add a,r2 mov r2,a clr a addc a,r3 mov r3,a clr c mov a,r2 subb a,_StallDetector mov a,r3 subb a,(_StallDetector + 1) jnc 00130$ C$MotionControl.c$665$5$10 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:665: HandleStallEvent(); ljmp _HandleStallEvent 00123$: C$MotionControl.c$668$2$8 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:668: else if (PosSensor == OFF) jnb _P1_4,00130$ C$MotionControl.c$670$4$11 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:670: if (StallDetector > (GapSize + 20)) mov a,#0x14 add a,_GapSize mov r2,a clr a addc a,(_GapSize + 1) mov r3,a clr c mov a,r2 subb a,_StallDetector mov a,r3 subb a,(_StallDetector + 1) jnc 00130$ C$MotionControl.c$672$5$12 ==. ; C:\SiLabs\Optec Programs\HSFW_HID_SDCC_2\MotionControl.c:672: HandleStallEvent(); C$MotionControl.c$678$2$1 ==. XG$OperateStepper$0$0 ==. ljmp _HandleStallEvent 00130$: ret It looks to me like the compiler is NOT optimizing out this second if statement from the looks of the asm but if that is the case why does the IDE not allow me so set a breakpoint there? Maybe it's just a dumb IDE!

  Read the article

• Finding the heaviest length-constrained path in a weighted Binary Tree

  - by Hristo

  UPDATE I worked out an algorithm that I think runs in O(n*k) running time. Below is the pseudo-code: routine heaviestKPath( T, k ) // create 2D matrix with n rows and k columns with each element = -8 // we make it size k+1 because the 0th column must be all 0s for a later // function to work properly and simplicity in our algorithm matrix = new array[ T.getVertexCount() ][ k + 1 ] (-8); // set all elements in the first column of this matrix = 0 matrix[ n ][ 0 ] = 0; // fill our matrix by traversing the tree traverseToFillMatrix( T.root, k ); // consider a path that would arc over a node globalMaxWeight = -8; findArcs( T.root, k ); return globalMaxWeight end routine // node = the current node; k = the path length; node.lc = node’s left child; // node.rc = node’s right child; node.idx = node’s index (row) in the matrix; // node.lc.wt/node.rc.wt = weight of the edge to left/right child; routine traverseToFillMatrix( node, k ) if (node == null) return; traverseToFillMatrix(node.lc, k ); // recurse left traverseToFillMatrix(node.rc, k ); // recurse right // in the case that a left/right child doesn’t exist, or both, // let’s assume the code is smart enough to handle these cases matrix[ node.idx ][ 1 ] = max( node.lc.wt, node.rc.wt ); for i = 2 to k { // max returns the heavier of the 2 paths matrix[node.idx][i] = max( matrix[node.lc.idx][i-1] + node.lc.wt, matrix[node.rc.idx][i-1] + node.rc.wt); } end routine // node = the current node, k = the path length routine findArcs( node, k ) if (node == null) return; nodeMax = matrix[node.idx][k]; longPath = path[node.idx][k]; i = 1; j = k-1; while ( i+j == k AND i < k ) { left = node.lc.wt + matrix[node.lc.idx][i-1]; right = node.rc.wt + matrix[node.rc.idx][j-1]; if ( left + right > nodeMax ) { nodeMax = left + right; } i++; j--; } // if this node’s max weight is larger than the global max weight, update if ( globalMaxWeight < nodeMax ) { globalMaxWeight = nodeMax; } findArcs( node.lc, k ); // recurse left findArcs( node.rc, k ); // recurse right end routine Let me know what you think. Feedback is welcome. I think have come up with two naive algorithms that find the heaviest length-constrained path in a weighted Binary Tree. Firstly, the description of the algorithm is as follows: given an n-vertex Binary Tree with weighted edges and some value k, find the heaviest path of length k. For both algorithms, I'll need a reference to all vertices so I'll just do a simple traversal of the Tree to have a reference to all vertices, with each vertex having a reference to its left, right, and parent nodes in the tree. Algorithm 1 For this algorithm, I'm basically planning on running DFS from each node in the Tree, with consideration to the fixed path length. In addition, since the path I'm looking for has the potential of going from left subtree to root to right subtree, I will have to consider 3 choices at each node. But this will result in a O(n*3^k) algorithm and I don't like that. Algorithm 2 I'm essentially thinking about using a modified version of Dijkstra's Algorithm in order to consider a fixed path length. Since I'm looking for heaviest and Dijkstra's Algorithm finds the lightest, I'm planning on negating all edge weights before starting the traversal. Actually... this doesn't make sense since I'd have to run Dijkstra's on each node and that doesn't seem very efficient much better than the above algorithm. So I guess my main questions are several. Firstly, do the algorithms I've described above solve the problem at hand? I'm not totally certain the Dijkstra's version will work as Dijkstra's is meant for positive edge values. Now, I am sure there exist more clever/efficient algorithms for this... what is a better algorithm? I've read about "Using spine decompositions to efficiently solve the length-constrained heaviest path problem for trees" but that is really complicated and I don't understand it at all. Are there other algorithms that tackle this problem, maybe not as efficiently as spine decomposition but easier to understand? Thanks.

  Read the article

< Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >