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  • java setting resolution and print size for an Image

    - by Ingrid
    I wrote a program that generates a BufferedImage to be displayed on the screen and then printed. Part of the image includes grid lines that are 1 pixel wide. That is, the line is 1 pixel, with about 10 pixels between lines. Because of screen resolution, the image is displayed much bigger than that, with several pixels for each line. I'd like to draw it smaller, but when I scale the image (either by using Image.getScaledInstance or Graphics2D.scale), I lose significant amounts of detail. I'd like to print the image as well, and am dealing with the same problem. In that case, I am using this code to set the resolution: HashPrintRequestAttributeSet set = new HashPrintRequestAttributeSet(); PrinterResolution pr = new PrinterResolution(250, 250, ResolutionSyntax.DPI); set.add(pr); job.print(set); which works to make the image smaller without losing detail. But the problem is that the image is cut off at the same boundary as if I hadn't set the resolution. I'm also confused because I expected a larger number of DPI to make a smaller image, but it's working the other way. I'm using java 1.6 on Windows 7 with eclipse.

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  • HTML5 on iPhone Safari - data stored by localStorage does not always persist. Why?

    - by Aerodyne
    Hi, I write a simple iPhone web app using HTML5's localStorage. Tests on a 2G device show that data stored using localStorage does not persist after the Safari process is killed although the opened Safari windows are remembered. The data is also lost in a case where I am on a different site on a different Safari window, then I change the window to where the web app in subject is shown. When Safari loads the page it automatically refreshes the page. Then the data is lost. This is a simple test code: <html> <head> <meta name="viewport" content="height=device-height, width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" /> </head> <body> <script> alert("1:" + localStorage.getItem("test")); localStorage.setItem("test", "123"); alert("2:" + localStorage.getItem("test")); </script> </body> As far as I understand the data should persist! Can anyone shed some light on this behavior? What should I do to get the persistence to work? Thanks! Tom.

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  • What is the best approach to embed mp4 for the iPhone without using JavaScript?

    - by usingtechnology
    I am trying to troubleshoot this code and am running into a dead-end, so I thought I would ask my first question here. I have three questions: 1) What is the best approach to embed an mp4 for an iPhone specific view, preferably without using Javascript? 2) Are there any preferred practices to debug code on an iPhone? 3) Can anyone tell me what is wrong with my specific code below? I should mention upfront that the variable $fileName does indeed contain the correct info, I've just omitted that portion of the code. Also, the poster image does flicker for a brief moment before I receive the greyed out, broken QuickTime image so that is an indication that this is partially working. Code: <object width="448" height="335" classid="clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B" codebase="http://www.apple.com/qtactivex/qtplugin.cab"> <param name="src" value="/libraries/images/$fileName.jpg" /> <param name="href" value="/libraries/media/$fileName.mp4" /> <param name="target" value="myself" /> <param name="controller" value="true" /> <param name="autoplay" value="false" /> <param name="scale" value="aspect" /> <embed src="/libraries/images/$fileName.jpg" href="/libraries/media/$fileName.mp4" type="video/mp4" target="myself" width="448" height="335" scale="aspect" controller="false" autoplay="false"> </embed> </object>

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  • Image rotate opecv error

    - by avd
    When I use this code to rotate the image, the destination image size remains same and hence the image gets clipped. Please provide me a way/code snippet to resize accordingly (like matlab does in imrotate) so that image does not get clipped and outlier pixels gets filled with all white instead of black. void imrotate(std::string imgPath,std::string angleStr,std::string outPath) { size_t found1,found2; found1=imgPath.find_last_of('/'); found2=imgPath.size()-4; IplImage* src=cvLoadImage(imgPath.c_str(), -1);; IplImage* dst; dst = cvCloneImage( src ); int angle = atoi(angleStr.c_str()); CvMat* rot_mat = cvCreateMat(2,3,CV_32FC1); CvPoint2D32f center = cvPoint2D32f( src->width/2, src->height/2 ); double scale = 1; cv2DRotationMatrix( center, angle, scale, rot_mat ); cvWarpAffine( src, dst, rot_mat); char angStr[4]; sprintf(angStr,"%d",angle); cvSaveImage(string(outPath+imgPath.substr(found1+1,found2-found1-1)+"_"+angStr+".jpg").c_str(),dst); cvReleaseImage(&src); cvReleaseImage(&dst); cvReleaseMat( &rot_mat ); } Original Image: Rotated Image:

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  • Design patterns for Caching Images in a MVC?

    - by Onema
    Hi, I'm designing an image cache system that will be used in an MVC CMS. The main purpose of the image cacher is to modify images: scale, crop, etc and cache them in the client site. I have created an image cache Model and Mapper that interact with the Database, to keep track of the images and know what kind of actions have been applied to them (scale, crop, etc). In addition to the Model and Mapper I have created a ImageCacher Class that is used by the API to manage the Model and image creation based on arguments passed by the client site, this class creates the images and generates the links to the images for the View. A coworker argued that I need to include the functionality of this last Class inside the Model, as the bulk of the logic should go in the model. I respectfully disagree with him since I feel the model's responsibility is to deal with the information about the images cached at the database level, and the responsibility of the ImageCacher Class is to create the url/image that we will be caching (keeping the single responsibility principle). In addition to this I believe that a model should not have Presentation-related features, like creating or showing images. Does anyone have any insight on this? is there a particular design pattern that would make this division of tasks clear and and the image cacher reusable? Should I add all the logic in the Model? Thank you.

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  • Bitmap issue in Samsung Galaxy S3

    - by user1531240
    I wrote a method to change Bitmap from camera shot : public Bitmap bitmapChange(Bitmap bm) { /* get original image size */ int w = bm.getWidth(); int h = bm.getHeight(); /* check the image's orientation */ float scale = w / h; if(scale < 1) { /* if the orientation is portrait then scaled and show on the screen*/ float scaleWidth = (float) 90 / (float) w; float scaleHeight = (float) 130 / (float) h; Matrix mtx = new Matrix(); mtx.postScale(scaleWidth, scaleHeight); Bitmap rotatedBMP = Bitmap.createBitmap(bm, 0, 0, w, h, mtx, true); return rotatedBMP; } else { /* if the orientation is landscape then rotate 90 */ float scaleWidth = (float) 130 / (float) w; float scaleHeight = (float) 90 / (float) h; Matrix mtx = new Matrix(); mtx.postScale(scaleWidth, scaleHeight); mtx.postRotate(90); Bitmap rotatedBMP = Bitmap.createBitmap(bm, 0, 0, w, h, mtx, true); return rotatedBMP; } } It works fine in another Android device, even Galaxy Nexus but in Samsung Galaxy S3, the scaled image doesn't show on screen. I tried to mark the bitmapChange method , let it show the original size Bitmap on screen but S3 also show nothing on screen. The information of variables in eclipse is here. The information of sony xperia is here. xperia and other device is working fine.

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  • live image edit , and crop

    - by 422
    I was just thinking, which is always dangerous. We use Valums Image uploader. Aside from that, I am looking for an inline image editor, but with a difference. User uploads an image ( lets say 800 x 600 ) Our system wants to see the image ( 170 x 32 ) now I know we can use php to resize images. But I was thinking, does anyone know of a system, where we can display the image, and user can scale, and crop image ( with say a predefined overlay ) By that they scale down to nearest acceptable size, and then click crop tool, which shows a div overlay with say 70% transparency that they can drag over the image, and then click crop. So image is cropped to exact size we need, then can save . I am sure I have seen some jquery stuff done like this, just cannot for life of me find it. Essentialy, we would like to offer a simple client side image processor, thats lightweight, and then the ability to save what they did . Sorry no code to show, as its more of a request. Regards

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  • How can I prevent the scaling of a UIWebview's content after reorientation?

    - by frankhermes
    I'm building an iOS 5/6 app that has a UIWebView. It loads some HTML that I have embedded in my app. Now when I rotate my device, the WebView changes its size (as I want it to fill the entire width of the screen). And then it gets weird: some content gets scaled up and some content doesn't get scaled up. See this image with some example text in it: As you can see, the header (H6) stays the same, while the paragraph gets scaled up. Does anybody have an idea how to prevent this? I want the html to look the same in landscape as it does in portrait mode. I've tried setting the viewport scaling to 1: <meta name="viewport" content="initial-scale=1.0,max-scale=1.0"> but that doesn't help. The body's font-size style is set to 14px, but changing that to 14pt or a percentage also made no difference. Setting the width of the body to 100% also didn't help. Strangely, removing the line break (<br/>) that's in the text fixes it but I need line breaks to be in there so that's no solution. The only thing that does work is reloading the UIWebView's content after an orientation change, but that doesn't prevent it from looking wrong during rotation, and it resets any scrolling that the user may have done. Any ideas?

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  • How to add an object to a html string?

    - by Philippe Maes
    I'm trying to load several images by a drop action and than resizing them and adding them as a thumbnail. The resize part is very important because the images can be very large and I want to make the thumbnails small of size. Here is my code: loadingGif(drop); for (var i=0;i<files.length;i++) { var file = files[i]; var reader = new FileReader(); reader.onload = function(e) { var src = e.target.result; var img = document.createElement('img'); img.src = src; var scale = 100/img.height; img.height = 100; img.width = scale*img.width; output.push('<div id="imagecontainer"><div id="image">'+img+'</div><div id="delimage"><img src="img/del.jpg"" /></div></div>'); if(output.length == files.length) { drop.removeChild(drop.lastChild); drop.innerHTML += output.join(''); output.length = 0; } } reader.readAsDataURL(file); } As you can probably tell I insert a loading gif image in my dropzone until all files are loaded (output.length == files.length). When a file is loaded I add html to an array which I will print if the load is complete. The problem is I can't seem to add the img object (I need this object to resize the image) to the html string, which seems obvious as the img is an object... So my question to you guys is: how do I do this? :)

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  • Mobile site not rendering mobile within iframe

    - by user2788371
    I'm launching a mobile version of an existing corporate web application that currently loads in an iframe for corporate authentication purposes. When accessing the web app's direct link from a mobile device, it displays beautifully. The problem is that when accessing through the iframe, the site doesn't seem to scale correctly and it looks more like I'm accessing the desktop version of the site. Any suggestions on how make the site within the iframe recognize the mobile device's width and adjust appropriately? I've tried setting the viewport within the HTML and CSS of the site being loaded and even then I'm not getting the change I expect on my iPhone. I haven't had the opportunity to test an Android yet but within our company, iOS is the most important. Some of snippets of code I have tried are listed below. I've also tried 480px and device-width (which I believe I can't access because the iframe is a different domain). Unfortunately, modifying the iframe page and settings are not an option. Also, Javascript cannot be used as a solution for other reasons. Within HTML of web app site: <meta name="viewport" content="width=320px, initial-scale=1.0, user-scalable=no" /> Within CSS of web app site: @viewport { width: 320px; } The above CSS does not seem to render even when not used in device specific @media code.

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  • opengl problem works on droid but not droid eris and others.

    - by nathan
    This GlRenderer works fine on the moto droid, but does not work well at all on droid eris or other android phones does anyone know why? package com.ntu.way2fungames.spacehockeybase; import java.io.DataInputStream; import java.io.IOException; import java.nio.Buffer; import java.nio.FloatBuffer; import javax.microedition.khronos.egl.EGLConfig; import javax.microedition.khronos.opengles.GL10; import com.ntu.way2fungames.LoadFloatArray; import com.ntu.way2fungames.OGLTriReader; import android.content.res.AssetManager; import android.content.res.Resources; import android.opengl.GLU; import android.opengl.GLSurfaceView.Renderer; import android.os.Handler; import android.os.Message; public class GlRenderer extends Thread implements Renderer { private float drawArray[]; private float yoff; private float yoff2; private long lastRenderTime; private float[] yoffs= new float[10]; int Width; int Height; private float[] pixelVerts = new float[] { +.0f,+.0f,2, +.5f,+.5f,0, +.5f,-.5f,0, +.0f,+.0f,2, +.5f,-.5f,0, -.5f,-.5f,0, +.0f,+.0f,2, -.5f,-.5f,0, -.5f,+.5f,0, +.0f,+.0f,2, -.5f,+.5f,0, +.5f,+.5f,0, }; @Override public void run() { } private float[] arenaWalls = new float[] { 8.00f,2.00f,1f,2f,2f,1f,2.00f,8.00f,1f,8.00f,2.00f,1f,2.00f,8.00f,1f,8.00f,8.00f,1f, 2.00f,8.00f,1f,2f,2f,1f,0.00f,0.00f,0f,2.00f,8.00f,1f,0.00f,0.00f,0f,0.00f,10.00f,0f, 8.00f,8.00f,1f,2.00f,8.00f,1f,0.00f,10.00f,0f,8.00f,8.00f,1f,0.00f,10.00f,0f,10.00f,10.00f,0f, 2f,2f,1f,8.00f,2.00f,1f,10.00f,0.00f,0f,2f,2f,1f,10.00f,0.00f,0f,0.00f,0.00f,0f, 8.00f,2.00f,1f,8.00f,8.00f,1f,10.00f,10.00f,0f,8.00f,2.00f,1f,10.00f,10.00f,0f,10.00f,0.00f,0f, 10.00f,10.00f,0f,0.00f,10.00f,0f,0.00f,0.00f,0f,10.00f,10.00f,0f,0.00f,0.00f,0f,10.00f,0.00f,0f, 8.00f,6.00f,1f,8.00f,4.00f,1f,122f,4.00f,1f,8.00f,6.00f,1f,122f,4.00f,1f,122f,6.00f,1f, 8.00f,6.00f,1f,122f,6.00f,1f,120f,7.00f,0f,8.00f,6.00f,1f,120f,7.00f,0f,10.00f,7.00f,0f, 122f,4.00f,1f,8.00f,4.00f,1f,10.00f,3.00f,0f,122f,4.00f,1f,10.00f,3.00f,0f,120f,3.00f,0f, 480f,10.00f,0f,470f,10.00f,0f,470f,0.00f,0f,480f,10.00f,0f,470f,0.00f,0f,480f,0.00f,0f, 478f,2.00f,1f,478f,8.00f,1f,480f,10.00f,0f,478f,2.00f,1f,480f,10.00f,0f,480f,0.00f,0f, 472f,2f,1f,478f,2.00f,1f,480f,0.00f,0f,472f,2f,1f,480f,0.00f,0f,470f,0.00f,0f, 478f,8.00f,1f,472f,8.00f,1f,470f,10.00f,0f,478f,8.00f,1f,470f,10.00f,0f,480f,10.00f,0f, 472f,8.00f,1f,472f,2f,1f,470f,0.00f,0f,472f,8.00f,1f,470f,0.00f,0f,470f,10.00f,0f, 478f,2.00f,1f,472f,2f,1f,472f,8.00f,1f,478f,2.00f,1f,472f,8.00f,1f,478f,8.00f,1f, 478f,846f,1f,472f,846f,1f,472f,852f,1f,478f,846f,1f,472f,852f,1f,478f,852f,1f, 472f,852f,1f,472f,846f,1f,470f,844f,0f,472f,852f,1f,470f,844f,0f,470f,854f,0f, 478f,852f,1f,472f,852f,1f,470f,854f,0f,478f,852f,1f,470f,854f,0f,480f,854f,0f, 472f,846f,1f,478f,846f,1f,480f,844f,0f,472f,846f,1f,480f,844f,0f,470f,844f,0f, 478f,846f,1f,478f,852f,1f,480f,854f,0f,478f,846f,1f,480f,854f,0f,480f,844f,0f, 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350f,0.00f,0f,360f,0.00f,0f,360f,10.00f,0f,350f,0.00f,0f,360f,10.00f,0f,350f,10.00f,0f, 358f,6.00f,1f,472f,6.00f,1f,470f,7.00f,0f,358f,6.00f,1f,470f,7.00f,0f,360f,7.00f,0f, 472f,4.00f,1f,358f,4.00f,1f,360f,3.00f,0f,472f,4.00f,1f,360f,3.00f,0f,470f,3.00f,0f, 472f,4.00f,1f,472f,6.00f,1f,358f,6.00f,1f,472f,4.00f,1f,358f,6.00f,1f,358f,4.00f,1f, 472f,848f,1f,472f,850f,1f,358f,850f,1f,472f,848f,1f,358f,850f,1f,358f,848f,1f, 472f,848f,1f,358f,848f,1f,360f,847f,0f,472f,848f,1f,360f,847f,0f,470f,847f,0f, 358f,850f,1f,472f,850f,1f,470f,851f,0f,358f,850f,1f,470f,851f,0f,360f,851f,0f, 350f,844f,0f,360f,844f,0f,360f,854f,0f,350f,844f,0f,360f,854f,0f,350f,854f,0f, 352f,852f,1f,352f,846f,1f,350f,844f,0f,352f,852f,1f,350f,844f,0f,350f,854f,0f, 358f,852f,1f,352f,852f,1f,350f,854f,0f,358f,852f,1f,350f,854f,0f,360f,854f,0f, 352f,846f,1f,358f,846f,1f,360f,844f,0f,352f,846f,1f,360f,844f,0f,350f,844f,0f, 358f,846f,1f,358f,852f,1f,360f,854f,0f,358f,846f,1f,360f,854f,0f,360f,844f,0f, 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350f,844f,0f,350f,854f,0f,345.45f,836.34f,-0.50f,350f,844f,0f,345.45f,836.34f,-0.50f,345.45f,826.76f,-0.50f, 360f,847f,0f,470f,847f,0f,460.49f,829.63f,-0.50f,360f,847f,0f,460.49f,829.63f,-0.50f,355.04f,829.63f,-0.50f, 470f,7.00f,0f,360f,7.00f,0f,355.04f,24.37f,-0.50f,470f,7.00f,0f,355.04f,24.37f,-0.50f,460.49f,24.37f,-0.50f, 350f,10.00f,0f,350f,0.00f,0f,345.45f,17.66f,-0.50f,350f,10.00f,0f,345.45f,17.66f,-0.50f,345.45f,27.24f,-0.50f, 130f,10.00f,0f,130f,0.00f,0f,134.55f,17.66f,-0.50f,130f,10.00f,0f,134.55f,17.66f,-0.50f,134.55f,27.24f,-0.50f, 473f,844f,0f,473f,10f,0f,463.36f,27.24f,-0.50f,473f,844f,0f,463.36f,27.24f,-0.50f,463.36f,826.76f,-0.50f, 7f,10f,0f,7f,844f,0f,16.64f,826.76f,-0.50f,7f,10f,0f,16.64f,826.76f,-0.50f,16.64f,27.24f,-0.50f, 120f,7.00f,0f,10.00f,7.00f,0f,19.51f,24.37f,-0.50f,120f,7.00f,0f,19.51f,24.37f,-0.50f,124.96f,24.37f,-0.50f, 120f,7.00f,0f,130f,10.00f,0f,134.55f,27.24f,-0.50f,120f,7.00f,0f,134.55f,27.24f,-0.50f,124.96f,24.37f,-0.50f, 10.00f,7.00f,0f,7f,10f,0f,16.64f,27.24f,-0.50f,10.00f,7.00f,0f,16.64f,27.24f,-0.50f,19.51f,24.37f,-0.50f, 350f,10.00f,0f,360f,7.00f,0f,355.04f,24.37f,-0.50f,350f,10.00f,0f,355.04f,24.37f,-0.50f,345.45f,27.24f,-0.50f, 473f,10f,0f,470f,7.00f,0f,460.49f,24.37f,-0.50f,473f,10f,0f,460.49f,24.37f,-0.50f,463.36f,27.24f,-0.50f, 473f,844f,0f,470f,847f,0f,460.49f,829.63f,-0.50f,473f,844f,0f,460.49f,829.63f,-0.50f,463.36f,826.76f,-0.50f, 360f,847f,0f,350f,844f,0f,345.45f,826.76f,-0.50f,360f,847f,0f,345.45f,826.76f,-0.50f,355.04f,829.63f,-0.50f, 130f,844f,0f,120f,847f,0f,124.96f,829.63f,-0.50f,130f,844f,0f,124.96f,829.63f,-0.50f,134.55f,826.76f,-0.50f, 7f,844f,0f,10f,847f,0f,19.51f,829.63f,-0.50f,7f,844f,0f,19.51f,829.63f,-0.50f,16.64f,826.76f,-0.50f, 19.51f,829.63f,-0.50f,124.96f,829.63f,-0.50f,136.47f,789.37f,-2f,19.51f,829.63f,-0.50f,136.47f,789.37f,-2f,41.56f,789.37f,-2f, 134.55f,826.76f,-0.50f,134.55f,836.34f,-0.50f,145.09f,795.41f,-2f,134.55f,826.76f,-0.50f,145.09f,795.41f,-2f,145.09f,786.78f,-2f, 345.45f,826.76f,-0.50f,345.45f,836.34f,-0.50f,334.91f,795.41f,-2f,345.45f,826.76f,-0.50f,334.91f,795.41f,-2f,334.91f,786.78f,-2f, 355.04f,829.63f,-0.50f,460.49f,829.63f,-0.50f,438.44f,789.37f,-2f,355.04f,829.63f,-0.50f,438.44f,789.37f,-2f,343.53f,789.37f,-2f, 460.49f,24.37f,-0.50f,355.04f,24.37f,-0.50f,343.53f,64.63f,-2f,460.49f,24.37f,-0.50f,343.53f,64.63f,-2f,438.44f,64.63f,-2f, 345.45f,27.24f,-0.50f,345.45f,17.66f,-0.50f,334.91f,58.59f,-2f,345.45f,27.24f,-0.50f,334.91f,58.59f,-2f,334.91f,67.22f,-2f, 134.55f,27.24f,-0.50f,134.55f,17.66f,-0.50f,145.09f,58.59f,-2f,134.55f,27.24f,-0.50f,145.09f,58.59f,-2f,145.09f,67.22f,-2f, 463.36f,826.76f,-0.50f,463.36f,27.24f,-0.50f,441.03f,67.22f,-2f,463.36f,826.76f,-0.50f,441.03f,67.22f,-2f,441.03f,786.78f,-2f, 16.64f,27.24f,-0.50f,16.64f,826.76f,-0.50f,38.97f,786.78f,-2f,16.64f,27.24f,-0.50f,38.97f,786.78f,-2f,38.97f,67.22f,-2f, 124.96f,24.37f,-0.50f,19.51f,24.37f,-0.50f,41.56f,64.63f,-2f,124.96f,24.37f,-0.50f,41.56f,64.63f,-2f,136.47f,64.63f,-2f, 124.96f,24.37f,-0.50f,134.55f,27.24f,-0.50f,145.09f,67.22f,-2f,124.96f,24.37f,-0.50f,145.09f,67.22f,-2f,136.47f,64.63f,-2f, 19.51f,24.37f,-0.50f,16.64f,27.24f,-0.50f,38.97f,67.22f,-2f,19.51f,24.37f,-0.50f,38.97f,67.22f,-2f,41.56f,64.63f,-2f, 345.45f,27.24f,-0.50f,355.04f,24.37f,-0.50f,343.53f,64.63f,-2f,345.45f,27.24f,-0.50f,343.53f,64.63f,-2f,334.91f,67.22f,-2f, 463.36f,27.24f,-0.50f,460.49f,24.37f,-0.50f,438.44f,64.63f,-2f,463.36f,27.24f,-0.50f,438.44f,64.63f,-2f,441.03f,67.22f,-2f, 463.36f,826.76f,-0.50f,460.49f,829.63f,-0.50f,438.44f,789.37f,-2f,463.36f,826.76f,-0.50f,438.44f,789.37f,-2f,441.03f,786.78f,-2f, 355.04f,829.63f,-0.50f,345.45f,826.76f,-0.50f,334.91f,786.78f,-2f,355.04f,829.63f,-0.50f,334.91f,786.78f,-2f,343.53f,789.37f,-2f, 134.55f,826.76f,-0.50f,124.96f,829.63f,-0.50f,136.47f,789.37f,-2f,134.55f,826.76f,-0.50f,136.47f,789.37f,-2f,145.09f,786.78f,-2f, 16.64f,826.76f,-0.50f,19.51f,829.63f,-0.50f,41.56f,789.37f,-2f,16.64f,826.76f,-0.50f,41.56f,789.37f,-2f,38.97f,786.78f,-2f, }; private float[] backgroundData = new float[] { // # ,Scale, Speed, 300 , 1.05f, .001f, 150 , 1.07f, .002f, 075 , 1.10f, .003f, 040 , 1.12f, .006f, 20 , 1.15f, .012f, 10 , 1.25f, .025f, 05 , 1.50f, .050f, 3 , 2.00f, .100f, 2 , 3.00f, .200f, }; private float[] triangleCoords = new float[] { 0, -25, 0, -.75f, -1, 0, +.75f, -1, 0, 0, +2, 0, -.99f, -1, 0, .99f, -1, 0, }; private float[] triangleColors = new float[] { 1.0f, 1.0f, 1.0f, 0.05f, 1.0f, 1.0f, 1.0f, 0.5f, 1.0f, 1.0f, 1.0f, 0.5f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 0.5f, 1.0f, 1.0f, 1.0f, 0.5f, }; private float[] drawArray2; private FloatBuffer drawBuffer2; private float[] colorArray2; private static FloatBuffer colorBuffer; private static FloatBuffer triangleBuffer; private static FloatBuffer quadBuffer; private static FloatBuffer drawBuffer; private float[] backgroundVerts; private FloatBuffer backgroundVertsWrapped; private float[] backgroundColors; private Buffer backgroundColorsWraped; private FloatBuffer backgroundColorsWrapped; private FloatBuffer arenaWallsWrapped; private FloatBuffer arenaColorsWrapped; private FloatBuffer arena2VertsWrapped; private FloatBuffer arena2ColorsWrapped; private long wallHitStartTime; private int wallHitDrawTime; private FloatBuffer pixelVertsWrapped; private float[] wallHit; private FloatBuffer pixelColorsWrapped; //private float[] pitVerts; private Resources lResources; private FloatBuffer pitVertsWrapped; private FloatBuffer pitColorsWrapped; private boolean arena2; private long lastStartTime; private long startTime; private int state=1; private long introEndTime; protected long introTotalTime =8000; protected long introStartTime; private boolean initDone= false; private static int stateIntro = 0; private static int stateGame = 1; public GlRenderer(spacehockey nspacehockey) { lResources = nspacehockey.getResources(); nspacehockey.SetHandlerToGLRenderer(new Handler() { @Override public void handleMessage(Message m) { if (m.what ==0){ wallHit = m.getData().getFloatArray("wall hit"); wallHitStartTime =System.currentTimeMillis(); wallHitDrawTime = 1000; }else if (m.what ==1){ //state = stateIntro; introEndTime= System.currentTimeMillis()+introTotalTime ; introStartTime = System.currentTimeMillis(); } }}); } public void onSurfaceCreated(GL10 gl, EGLConfig config) { gl.glShadeModel(GL10.GL_SMOOTH); gl.glClearColor(.01f, .01f, .01f, .1f); gl.glClearDepthf(1.0f); gl.glEnable(GL10.GL_DEPTH_TEST); gl.glDepthFunc(GL10.GL_LEQUAL); gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST); } private float SumOfStrideI(float[] data, int offset, int stride) { int sum= 0; for (int i=offset;i<data.length-1;i=i+stride){ sum = (int) (data[i]+sum); } return sum; } public void onDrawFrame(GL10 gl) { if (state== stateIntro){DrawIntro(gl);} if (state== stateGame){DrawGame(gl);} } private void DrawIntro(GL10 gl) { startTime = System.currentTimeMillis(); if (startTime< introEndTime){ float ptd = (float)(startTime- introStartTime)/(float)introTotalTime; float ptl = 1-ptd; gl.glClear(GL10.GL_COLOR_BUFFER_BIT);//dont move gl.glMatrixMode(GL10.GL_MODELVIEW); int setVertOff = 0; gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); gl.glEnableClientState(GL10.GL_COLOR_ARRAY); gl.glColorPointer(4, GL10.GL_FLOAT, 0, backgroundColorsWrapped); for (int i = 0; i < backgroundData.length / 3; i = i + 1) { int setoff = i * 3; int setVertLen = (int) backgroundData[setoff]; yoffs[i] = (backgroundData[setoff + 2]*(90+(ptl*250))) + yoffs[i]; if (yoffs[i] > Height) {yoffs[i] = 0;} gl.glPushMatrix(); //gl.glTranslatef(0, -(Height/2), 0); //gl.glScalef(1f, 1f+(ptl*2), 1f); //gl.glTranslatef(0, +(Height/2), 0); gl.glTranslatef(0, yoffs[i], i+60); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, backgroundVertsWrapped); gl.glDrawArrays(GL10.GL_TRIANGLES, (setVertOff * 2 * 3) - 0, (setVertLen * 2 * 3) - 1); gl.glTranslatef(0, -Height, 0); gl.glDrawArrays(GL10.GL_TRIANGLES, (setVertOff * 2 * 3) - 0, (setVertLen * 2 * 3) - 1); setVertOff = (int) (setVertOff + setVertLen); gl.glPopMatrix(); } gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); gl.glDisableClientState(GL10.GL_COLOR_ARRAY); }else{state = stateGame;} } private void DrawGame(GL10 gl) { lastStartTime = startTime; startTime = System.currentTimeMillis(); long moveTime = startTime-lastStartTime; gl.glClear(GL10.GL_COLOR_BUFFER_BIT);//dont move gl.glMatrixMode(GL10.GL_MODELVIEW); int setVertOff = 0; gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); gl.glEnableClientState(GL10.GL_COLOR_ARRAY); gl.glColorPointer(4, GL10.GL_FLOAT, 0, backgroundColorsWrapped); for (int i = 0; i < backgroundData.length / 3; i = i + 1) { int setoff = i * 3; int setVertLen = (int) backgroundData[setoff]; yoffs[i] = (backgroundData[setoff + 2]*moveTime) + yoffs[i]; if (yoffs[i] > Height) {yoffs[i] = 0;} gl.glPushMatrix(); gl.glTranslatef(0, yoffs[i], i+60); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, backgroundVertsWrapped); gl.glDrawArrays(GL10.GL_TRIANGLES, (setVertOff * 6) - 0, (setVertLen *6) - 1); gl.glTranslatef(0, -Height, 0); gl.glDrawArrays(GL10.GL_TRIANGLES, (setVertOff * 6) - 0, (setVertLen *6) - 1); setVertOff = (int) (setVertOff + setVertLen); gl.glPopMatrix(); } //arena frame gl.glPushMatrix(); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, arenaWallsWrapped); gl.glColorPointer(4, GL10.GL_FLOAT, 0, arenaColorsWrapped); gl.glColor4f(.1f, .5f, 1f, 1f); gl.glTranslatef(0, 0, 50); gl.glDrawArrays(GL10.GL_TRIANGLES, 0, (int)(arenaWalls.length / 3)); gl.glPopMatrix(); //arena2 frame if (arena2 == true){ gl.glLoadIdentity(); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, pitVertsWrapped); gl.glColorPointer(4, GL10.GL_FLOAT, 0, pitColorsWrapped); gl.glTranslatef(0, -Height, 40); gl.glDrawArrays(GL10.GL_TRIANGLES, 0, (int)(pitVertsWrapped.capacity() / 3)); } if (wallHitStartTime != 0) { float timeRemaining = (wallHitStartTime + wallHitDrawTime)-System.currentTimeMillis(); if (timeRemaining>0) { gl.glPushMatrix(); float percentDone = 1-(timeRemaining/wallHitDrawTime); gl.glLoadIdentity(); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, pixelVertsWrapped); gl.glColorPointer(4, GL10.GL_FLOAT, 0, pixelColorsWrapped); gl.glTranslatef(wallHit[0], wallHit[1], 0); gl.glScalef(8, Height*percentDone, 0); gl.glDrawArrays(GL10.GL_TRIANGLES, 0, 12); gl.glPopMatrix(); } else { wallHitStartTime = 0; } } gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); gl.glDisableClientState(GL10.GL_COLOR_ARRAY); } public void init(GL10 gl) { if (arena2 == true) { AssetManager assetManager = lResources.getAssets(); try { // byte[] ba = {111,111}; DataInputStream Dis = new DataInputStream(assetManager .open("arena2.ogl")); pitVertsWrapped = LoadFloatArray.FromDataInputStream(Dis); pitColorsWrapped = MakeFakeLighting(pitVertsWrapped.array(), .25f, .50f, 1f, 200, .5f); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } if ((Height != 854) || (Width != 480)) { arenaWalls = ScaleFloats(arenaWalls, Width / 480f, Height / 854f); } arenaWallsWrapped = FloatBuffer.wrap(arenaWalls); arenaColorsWrapped = MakeFakeLighting(arenaWalls, .03f, .16f, .33f, .33f, 3); pixelVertsWrapped = FloatBuffer.wrap(pixelVerts); pixelColorsWrapped = MakeFakeLighting(pixelVerts, .03f, .16f, .33f, .10f, 20); initDone=true; } public void onSurfaceChanged(GL10 gl, int nwidth, int nheight) { Width= nwidth; Height = nheight; // avoid division by zero if (Height == 0) Height = 1; // draw on the entire screen gl.glViewport(0, 0, Width, Height); // setup projection matrix gl.glMatrixMode(GL10.GL_PROJECTION); gl.glLoadIdentity(); gl.glOrthof(0, Width, Height, 0, 100, -100); // gl.glOrthof(-nwidth*2, nwidth*2, nheight*2,-nheight*2, 100, -100); // GLU.gluPerspective(gl, 180.0f, (float)nwidth / (float)nheight, // 1000.0f, -1000.0f); gl.glEnable(GL10.GL_BLEND); gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA); System.gc(); if (initDone == false){ SetupStars(); init(gl); } } public void SetupStars(){ backgroundVerts = new float[(int) SumOfStrideI(backgroundData,0,3)*triangleCoords.length]; backgroundColors = new float[(int) SumOfStrideI(backgroundData,0,3)*triangleColors.length]; int iii=0; int vc=0; float ascale=1; for (int i=0;i<backgroundColors.length-1;i=i+1){ if (iii==0){ascale = (float) Math.random();} if (vc==3){ backgroundColors[i]= (float) (triangleColors[iii]*(ascale)); }else if(vc==2){ backgroundColors[i]= (float) (triangleColors[iii]-(Math.random()*.2)); }else{ backgroundColors[i]= (float) (triangleColors[iii]-(Math.random()*.3)); } iii=iii+1;if (iii> triangleColors.length-1){iii=0;} vc=vc+1; if (vc>3){vc=0;} } int ii=0; int i =0; int set =0; while(ii<backgroundVerts.length-1){ float scale = (float) backgroundData[(set*3)+1]; int length= (int) backgroundData[(set*3)]; for (i=0;i<length;i=i+1){ if (set ==0){ AddVertsToArray(ScaleFloats(triangleCoords, scale,scale*.25f), backgroundVerts, (float)(Math.random()*Width),(float) (Math.random()*Height), ii); }else{ AddVertsToArray(ScaleFloats(triangleCoords, scale), backgroundVerts, (float)(Math.random()*Width),(float) (Math.random()*Height), ii);} ii=ii+triangleCoords.length; } set=set+1; } backgroundVertsWrapped = FloatBuffer.wrap(backgroundVerts); backgroundColorsWrapped = FloatBuffer.wrap(backgroundColors); } public void AddVertsToArray(float[] sva,float[]dva,float ox,float oy,int start){ //x for (int i=0;i<sva.length;i=i+3){ if((start+i)<dva.length){dva[start+i]= sva[i]+ox;} } //y for (int i=1;i<sva.length;i=i+3){ if((start+i)<dva.length){dva[start+i]= sva[i]+oy;} } //z for (int i=2;i<sva.length;i=i+3){ if((start+i)<dva.length){dva[start+i]= sva[i];} } } public FloatBuffer MakeFakeLighting(float[] sa,float r, float g,float b,float a,float multby){ float[] da = new float[((sa.length/3)*4)]; int vertex=0; for (int i=0;i<sa.length;i=i+3){ if (sa[i+2]>=1){ da[(vertex*4)+0]= r*multby*sa[i+2]; da[(vertex*4)+1]= g*multby*sa[i+2]; da[(vertex*4)+2]= b*multby*sa[i+2]; da[(vertex*4)+3]= a*multby*sa[i+2]; }else if (sa[i+2]<=-1){ float divisor = (multby*(-sa[i+2])); da[(vertex*4)+0]= r / divisor; da[(vertex*4)+1]= g / divisor; da[(vertex*4)+2]= b / divisor; da[(vertex*4)+3]= a / divisor; }else{ da[(vertex*4)+0]= r; da[(vertex*4)+1]= g; da[(vertex*4)+2]= b; da[(vertex*4)+3]= a; } vertex = vertex+1; } return FloatBuffer.wrap(da); } public float[] ScaleFloats(float[] va,float s){ float[] reta= new float[va.length]; for (int i=0;i<va.length;i=i+1){ reta[i]=va[i]*s; } return reta; } public float[] ScaleFloats(float[] va,float sx,float sy){ float[] reta= new float[va.length]; int cnt = 0; for (int i=0;i<va.length;i=i+1){ if (cnt==0){reta[i]=va[i]*sx;} else if (cnt==1){reta[i]=va[i]*sy;} else if (cnt==2){reta[i]=va[i];} cnt = cnt +1;if (cnt>2){cnt=0;} } return reta; } }

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  • CLSF & CLK 2013 Trip Report by Jeff Liu

    - by jamesmorris
    This is a contributed post from Jeff Liu, lead XFS developer for the Oracle mainline Linux kernel team. Recently, I attended both the China Linux Storage and Filesystem workshop (CLSF), and the China Linux Kernel conference (CLK), which were held in Shanghai. Here are the highlights for both events. CLSF - 17th October XFS update (led by Jeff Liu) XFS keeps rapid progress with a lot of changes, especially focused on the infrastructure/performance improvements as well as  new feature development.  This can be reflected with a sample statistics among XFS/Ext4+JBD2/Btrfs via: # git diff --stat --minimal -C -M v3.7..v3.12-rc4 -- fs/xfs|fs/ext4+fs/jbd2|fs/btrfs XFS: 141 files changed, 27598 insertions(+), 19113 deletions(-) Ext4+JBD2: 39 files changed, 10487 insertions(+), 5454 deletions(-) Btrfs: 70 files changed, 19875 insertions(+), 8130 deletions(-) What made up those changes in XFS? Self-describing metadata(CRC32c). This is a new feature and it contributed about 70% code changes, it can be enabled via `mkfs.xfs -m crc=1 /dev/xxx` for v5 superblock. Transaction log space reservation improvements. With this change, we can calculate the log space reservation at mount time rather than runtime to reduce the the CPU overhead. User namespace support. So both XFS and USERNS can be enabled on kernel configuration begin from Linux 3.10. Thanks Dwight Engen's efforts for this thing. Split project/group quota inodes. Originally, project quota can not be enabled with group quota at the same time because they were share the same quota file inode, now it works but only for v5 super block. i.e, CRC enabled. CONFIG_XFS_WARN, an new lightweight runtime debugger which can be deployed in production environment. Readahead log object recovery, this change can speed up the log replay progress significantly. Speculative preallocation inode tracking, clearing and throttling. The main purpose is to deal with inodes with post-EOF space due to speculative preallocation, support improved quota management to free up a significant amount of unwritten space when at or near EDQUOT. It support backgroup scanning which occurs on a longish interval(5 mins by default, tunable), and on-demand scanning/trimming via ioctl(2). Bitter arguments ensued from this session, especially for the comparison between Ext4 and Btrfs in different areas, I have to spent a whole morning of the 1st day answering those questions. We basically agreed on XFS is the best choice in Linux nowadays because: Stable, XFS has a good record in stability in the past 10 years. Fengguang Wu who lead the 0-day kernel test project also said that he has observed less error than other filesystems in the past 1+ years, I own it to the XFS upstream code reviewer, they always performing serious code review as well as testing. Good performance for large/small files, XFS does not works very well for small files has already been an old story for years. Best choice (maybe) for distributed PB filesystems. e.g, Ceph recommends delopy OSD daemon on XFS because Ext4 has limited xattr size. Best choice for large storage (>16TB). Ext4 does not support a single file more than around 15.95TB. Scalability, any objection to XFS is best in this point? :) XFS is better to deal with transaction concurrency than Ext4, why? The maximum size of the log in XFS is 2038MB compare to 128MB in Ext4. Misc. Ext4 is widely used and it has been proved fast/stable in various loads and scenarios, XFS just need more customers, and Btrfs is still on the road to be a manhood. Ceph Introduction (Led by Li Wang) This a hot topic.  Li gave us a nice introduction about the design as well as their current works. Actually, Ceph client has been included in Linux kernel since 2.6.34 and supported by Openstack since Folsom but it seems that it has not yet been widely deployment in production environment. Their major work is focus on the inline data support to separate the metadata and data storage, reduce the file access time, i.e, a file access need communication twice, fetch the metadata from MDS and then get data from OSD, and also, the small file access is limited by the network latency. The solution is, for the small files they would like to store the data at metadata so that when accessing a small file, the metadata server can push both metadata and data to the client at the same time. In this way, they can reduce the overhead of calculating the data offset and save the communication to OSD. For this feature, they have only run some small scale testing but really saw noticeable improvements. Test environment: Intel 2 CPU 12 Core, 64GB RAM, Ubuntu 12.04, Ceph 0.56.6 with 200GB SATA disk, 15 OSD, 1 MDS, 1 MON. The sequence read performance for 1K size files improved about 50%. I have asked Li and Zheng Yan (the core developer of Ceph, who also worked on Btrfs) whether Ceph is really stable and can be deployed at production environment for large scale PB level storage, but they can not give a positive answer, looks Ceph even does not spread over Dreamhost (subject to confirmation). From Li, they only deployed Ceph for a small scale storage(32 nodes) although they'd like to try 6000 nodes in the future. Improve Linux swap for Flash storage (led by Shaohua Li) Because of high density, low power and low price, flash storage (SSD) is a good candidate to partially replace DRAM. A quick answer for this is using SSD as swap. But Linux swap is designed for slow hard disk storage, so there are a lot of challenges to efficiently use SSD for swap. SWAPOUT swap_map scan swap_map is the in-memory data structure to track swap disk usage, but it is a slow linear scan. It will become a bottleneck while finding many adjacent pages in the use of SSD. Shaohua Li have changed it to a cluster(128K) list, resulting in O(1) algorithm. However, this apporoach needs restrictive cluster alignment and only enabled for SSD. IO pattern In most cases, the swap io is in interleaved pattern because of mutiple reclaimers or a free cluster is shared by all reclaimers. Even though block layer can merge interleaved IO to some extent, but we cannot count on it completely. Hence the per-cpu cluster is added base on the previous change, it can help reclaimer do sequential IO and the block layer will be easier to merge IO. TLB flush: If we're reclaiming one active page, we should first move the page from active lru list to inactive lru list, and then reclaim the page from inactive lru to swap it out. During the process, we need to clear PTE twice: first is 'A'(ACCESS) bit, second is 'P'(PRESENT) bit. Processors need to send lots of ipi which make the TLB flush really expensive. Some works have been done to improve this, including rework smp_call_functiom_many() or remove the first TLB flush in x86, but there still have some arguments here and only parts of works have been pushed to mainline. SWAPIN: Page fault does iodepth=1 sync io, but it's a little waste if only issue a page size's IO. The obvious solution is doing swap readahead. But the current in-kernel swap readahead is arbitary(always 8 pages), and it always doesn't perform well for both random and sequential access workload. Shaohua introduced a new flag for madvise(MADV_WILLNEED) to do swap prefetch, so the changes happen in userspace API and leave the in-kernel readahead unchanged(but I think some improvement can also be done here). SWAP discard As we know, discard is important for SSD write throughout, but the current swap discard implementation is synchronous. He changed it to async discard which allow discard and write run in the same time. Meanwhile, the unit of discard is also optimized to cluster. Misc: lock contention For many concurrent swapout and swapin , the lock contention such as anon_vma or swap_lock is high, so he changed the swap_lock to a per-swap lock. But there still have some lock contention in very high speed SSD because of swapcache address_space lock. Zproject (led by Bob Liu) Bob gave us a very nice introduction about the current memory compression status. Now there are 3 projects(zswap/zram/zcache) which all aim at smooth swap IO storm and promote performance, but they all have their own pros and cons. ZSWAP It is implemented based on frontswap API and it uses a dynamic allocater named Zbud to allocate free pages. Zbud means pairs of zpages are "buddied" and it can only store at most two compressed pages in one page frame, so the max compress ratio is 50%. Each page frame is lru-linked and can do shink in memory pressure. If the compressed memory pool reach its limitation, shink or reclaim happens. It decompress the page frame into two new allocated pages and then write them to real swap device, but it can fail when allocating the two pages. ZRAM Acts as a compressed ramdisk and used as swap device, and it use zsmalloc as its allocator which has high density but may have fragmentation issues. Besides, page reclaim is hard since it will need more pages to uncompress and free just one page. ZRAM is preferred by embedded system which may not have any real swap device. Now both ZRAM and ZSWAP are in driver/staging tree, and in the mm community there are some disscussions of merging ZRAM into ZSWAP or viceversa, but no agreement yet. ZCACHE Handles file page compression but it is removed out of staging recently. From industry (led by Tang Jie, LSI) An LSI engineer introduced several new produces to us. The first is raid5/6 cards that it use full stripe writes to improve performance. The 2nd one he introduced is SandForce flash controller, who can understand data file types (data entropy) to reduce write amplification (WA) for nearly all writes. It's called DuraWrite and typical WA is 0.5. What's more, if enable its Dynamic Logical Capacity function module, the controller can do data compression which is transparent to upper layer. LSI testing shows that with this virtual capacity enables 1x TB drive can support up to 2x TB capacity, but the application must monitor free flash space to maintain optimal performance and to guard against free flash space exhaustion. He said the most useful application is for datebase. Another thing I think it's worth to mention is that a NV-DRAM memory in NMR/Raptor which is directly exposed to host system. Applications can directly access the NV-DRAM via a memory address - using standard system call mmap(). He said that it is very useful for database logging now. This kind of NVM produces are beginning to appear in recent years, and it is said that Samsung is building a research center in China for related produces. IMHO, NVM will bring an effect to current os layer especially on file system, e.g. its journaling may need to redesign to fully utilize these nonvolatile memory. OCFS2 (led by Canquan Shen) Without a doubt, HuaWei is the biggest contributor to OCFS2 in the past two years. They have posted 46 upstream patches and 39 patches have been merged. Their current project is based on 32/64 nodes cluster, but they also tried 128 nodes at the experimental stage. The major work they are working is to support ATS (atomic test and set), it can be works with DLM at the same time. Looks this idea is inspired by the vmware VMFS locking, i.e, http://blogs.vmware.com/vsphere/2012/05/vmfs-locking-uncovered.html CLK - 18th October 2013 Improving Linux Development with Better Tools (Andi Kleen) This talk focused on how to find/solve bugs along with the Linux complexity growing. Generally, we can do this with the following kind of tools: Static code checkers tools. e.g, sparse, smatch, coccinelle, clang checker, checkpatch, gcc -W/LTO, stanse. This can help check a lot of things, simple mistakes, complex problems, but the challenges are: some are very slow, false positives, may need a concentrated effort to get false positives down. Especially, no static checker I found can follow indirect calls (“OO in C”, common in kernel): struct foo_ops { int (*do_foo)(struct foo *obj); } foo->do_foo(foo); Dynamic runtime checkers, e.g, thread checkers, kmemcheck, lockdep. Ideally all kernel code would come with a test suite, then someone could run all the dynamic checkers. Fuzzers/test suites. e.g, Trinity is a great tool, it finds many bugs, but needs manual model for each syscall. Modern fuzzers around using automatic feedback, but notfor kernel yet: http://taviso.decsystem.org/making_software_dumber.pdf Debuggers/Tracers to understand code, e.g, ftrace, can dump on events/oops/custom triggers, but still too much overhead in many cases to run always during debug. Tools to read/understand source, e.g, grep/cscope work great for many cases, but do not understand indirect pointers (OO in C model used in kernel), give us all “do_foo” instances: struct foo_ops { int (*do_foo)(struct foo *obj); } = { .do_foo = my_foo }; foo>do_foo(foo); That would be great to have a cscope like tool that understands this based on types/initializers XFS: The High Performance Enterprise File System (Jeff Liu) [slides] I gave a talk for introducing the disk layout, unique features, as well as the recent changes.   The slides include some charts to reflect the performances between XFS/Btrfs/Ext4 for small files. About a dozen users raised their hands when I asking who has experienced with XFS. I remembered that when I asked the same question in LinuxCon/Japan, only 3 people raised their hands, but they are Chris Mason, Ric Wheeler, and another attendee. The attendee questions were mainly focused on stability, and comparison with other file systems. Linux Containers (Feng Gao) The speaker introduced us that the purpose for those kind of namespaces, include mount/UTS/IPC/Network/Pid/User, as well as the system API/ABI. For the userspace tools, He mainly focus on the Libvirt LXC rather than us(LXC). Libvirt LXC is another userspace container management tool, implemented as one type of libvirt driver, it can manage containers, create namespace, create private filesystem layout for container, Create devices for container and setup resources controller via cgroup. In this talk, Feng also mentioned another two possible new namespaces in the future, the 1st is the audit, but not sure if it should be assigned to user namespace or not. Another is about syslog, but the question is do we really need it? In-memory Compression (Bob Liu) Same as CLSF, a nice introduction that I have already mentioned above. Misc There were some other talks related to ACPI based memory hotplug, smart wake-affinity in scheduler etc., but my head is not big enough to record all those things. -- Jeff Liu

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  • C# XNA Handle mouse events?

    - by user406470
    I'm making a 2D game engine called Clixel over on GitHub. The problem I have relates to two classes, ClxMouse and ClxButton. In it I have a mouse class - the code for that can be viewed here. ClxMouse using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; namespace org.clixel { public class ClxMouse : ClxSprite { private MouseState _curmouse, _lastmouse; public int Sensitivity = 3; public bool Lock = true; public Vector2 Change { get { return new Vector2(_curmouse.X - _lastmouse.X, _curmouse.Y - _lastmouse.Y); } } private int _scrollwheel; public int ScrollWheel { get { return _scrollwheel; } } public bool LeftDown { get { if (_curmouse.LeftButton == ButtonState.Pressed) return true; else return false; } } public bool RightDown { get { if (_curmouse.RightButton == ButtonState.Pressed) return true; else return false; } } public bool MiddleDown { get { if (_curmouse.MiddleButton == ButtonState.Pressed) return true; else return false; } } public bool LeftPressed { get { if (_curmouse.LeftButton == ButtonState.Pressed && _lastmouse.LeftButton == ButtonState.Released) return true; else return false; } } public bool RightPressed { get { if (_curmouse.RightButton == ButtonState.Pressed && _lastmouse.RightButton == ButtonState.Released) return true; else return false; } } public bool MiddlePressed { get { if (_curmouse.MiddleButton == ButtonState.Pressed && _lastmouse.MiddleButton == ButtonState.Released) return true; else return false; } } public bool LeftReleased { get { if (_curmouse.LeftButton == ButtonState.Released && _lastmouse.LeftButton == ButtonState.Pressed) return true; else return false; } } public bool RightReleased { get { if (_curmouse.RightButton == ButtonState.Released && _lastmouse.RightButton == ButtonState.Pressed) return true; else return false; } } public bool MiddleReleased { get { if (_curmouse.MiddleButton == ButtonState.Released && _lastmouse.MiddleButton == ButtonState.Pressed) return true; else return false; } } public MouseState CurMouse { get { return _curmouse; } } public MouseState LastMouse { get { return _lastmouse; } } public ClxMouse() : base(ClxG.Textures.Default.Cursor) { _curmouse = Mouse.GetState(); _lastmouse = _curmouse; CollisionBox = new Rectangle(ClxG.Screen.Center.X, ClxG.Screen.Center.Y, Texture.Width, Texture.Height); this.Solid = false; DefaultPosition = new Vector2(CollisionBox.X, CollisionBox.Y); Mouse.SetPosition(CollisionBox.X, CollisionBox.Y); } public ClxMouse(Texture2D _texture) : base(_texture) { _curmouse = Mouse.GetState(); _lastmouse = _curmouse; CollisionBox = new Rectangle(ClxG.Screen.Center.X, ClxG.Screen.Center.Y, Texture.Width, Texture.Height); DefaultPosition = new Vector2(CollisionBox.X, CollisionBox.Y); } public override void Update() { _lastmouse = _curmouse; _curmouse = Mouse.GetState(); if (_curmouse != _lastmouse) { if (ClxG.Game.IsActive) { _scrollwheel = _curmouse.ScrollWheelValue; Velocity = new Vector2(Change.X / Sensitivity, Change.Y / Sensitivity); if (Lock) Mouse.SetPosition(ClxG.Screen.Center.X, ClxG.Screen.Center.Y); _curmouse = Mouse.GetState(); } base.Update(); } } public override void Draw(SpriteBatch _sb) { base.Draw(_sb); } } } ClxButton using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Graphics; namespace org.clixel { public class ClxButton : ClxSprite { /// <summary> /// The color when the mouse is over the button /// </summary> public Color HoverColor; /// <summary> /// The color when the color is being clicked /// </summary> public Color ClickColor; /// <summary> /// The color when the button is inactive /// </summary> public Color InactiveColor; /// <summary> /// The color when the button is active /// </summary> public Color ActiveColor; /// <summary> /// The color after the button has been clicked. /// </summary> public Color ClickedColor; /// <summary> /// The text to be displayed on the button, set to "" if no text is needed. /// </summary> public string Text; /// <summary> /// The ClxText object to be displayed. /// </summary> public ClxText TextRender; /// <summary> /// The ClxState that should be ResetAndShow() when the button is clicked. /// </summary> public ClxState ClickState; /// <summary> /// Collision check to make sure onCollide() only runs once per frame, /// since only the mouse needs to be collision checked. /// </summary> private bool _runonce = false; /// <summary> /// Gets a value indicating whether this instance is colliding. /// </summary> /// <value> /// <c>true</c> if this instance is colliding; otherwise, <c>false</c>. /// </value> public bool IsColliding { get { return _runonce; } } /// <summary> /// Initializes a new instance of the <see cref="ClxButton"/> class. /// </summary> public ClxButton() : base(ClxG.Textures.Default.Button) { HoverColor = Color.Red; ClickColor = Color.Blue; InactiveColor = Color.Gray; ActiveColor = Color.White; ClickedColor = Color.Yellow; Text = Name + ID + " Unset!"; TextRender = new ClxText(); TextRender.Text = Text; TextRender.TextPadding = new Vector2(5, 5); ClickState = null; CollideObjects(ClxG.Mouse); } /// <summary> /// Initializes a new instance of the <see cref="ClxButton"/> class. /// </summary> /// <param name="_texture">The button texture.</param> public ClxButton(Texture2D _texture) : base(_texture) { HoverColor = Color.Red; ClickColor = Color.Blue; InactiveColor = Color.Gray; ActiveColor = Color.White; ClickedColor = Color.Yellow; Texture = _texture; Text = Name + ID; TextRender = new ClxText(); TextRender.Name = this.Name + ".TextRender"; TextRender.Text = Text; TextRender.TextPadding = new Vector2(5, 5); TextRender.Reset(); ClickState = null; CollideObjects(ClxG.Mouse); } /// <summary> /// Draws the debug information, run from ClxG.DrawDebug unless manual control is assumed. /// </summary> /// <param name="_sb">SpriteBatch used for drawing.</param> public override void DrawDebug(SpriteBatch _sb) { _runonce = false; TextRender.DrawDebug(_sb); _sb.Draw(Texture, ActualRectangle, new Rectangle(0, 0, Texture.Width, Texture.Height), DebugColor, Rotation, Origin, Flip, Layer); _sb.Draw(ClxG.Textures.Default.DebugBG, new Rectangle(ActualRectangle.X - DebugLineWidth, ActualRectangle.Y - DebugLineWidth, ActualRectangle.Width + DebugLineWidth * 2, ActualRectangle.Height + DebugLineWidth * 2), new Rectangle(0, 0, ClxG.Textures.Default.DebugBG.Width, ClxG.Textures.Default.DebugBG.Height), DebugOutline, Rotation, Origin, Flip, Layer - 0.1f); _sb.Draw(ClxG.Textures.Default.DebugBG, ActualRectangle, new Rectangle(0, 0, ClxG.Textures.Default.DebugBG.Width, ClxG.Textures.Default.DebugBG.Height), DebugBGColor, Rotation, Origin, Flip, Layer - 0.01f); } /// <summary> /// Draws using the SpriteBatch, run from ClxG.Draw unless manual control is assumed. /// </summary> /// <param name="_sb">SpriteBatch used for drawing.</param> public override void Draw(SpriteBatch _sb) { _runonce = false; TextRender.Draw(_sb); if (Visible) if (Debug) { DrawDebug(_sb); } else _sb.Draw(Texture, ActualRectangle, new Rectangle(0, 0, Texture.Width, Texture.Height), Color, Rotation, Origin, Flip, Layer); } /// <summary> /// Updates this instance. /// </summary> public override void Update() { if (this.Color != ActiveColor) this.Color = ActiveColor; TextRender.Layer = this.Layer + 0.03f; TextRender.Text = Text; TextRender.Scale = .5f; TextRender.Name = this.Name + ".TextRender"; TextRender.Origin = new Vector2(TextRender.CollisionBox.Center.X, TextRender.CollisionBox.Center.Y); TextRender.Center(this); TextRender.Update(); this.CollisionBox.Width = (int)(TextRender.CollisionBox.Width * TextRender.Scale) + (int)(TextRender.TextPadding.X * 2); this.CollisionBox.Height = (int)(TextRender.CollisionBox.Height * TextRender.Scale) + (int)(TextRender.TextPadding.Y * 2); base.Update(); } /// <summary> /// Collide event, takes the colliding object to call it's proper collision code. /// You'd want to use something like if(typeof(collider) == typeof(ClxObject) /// </summary> /// <param name="collider">The colliding object.</param> public override void onCollide(ClxObject collider) { if (!_runonce) { _runonce = true; UpdateEvents(); base.onCollide(collider); } } /// <summary> /// Updates the mouse based events. /// </summary> public void UpdateEvents() { onHover(); if (ClxG.Mouse.LeftReleased) { onLeftReleased(); return; } if (ClxG.Mouse.RightReleased) { onRightReleased(); return; } if (ClxG.Mouse.MiddleReleased) { onMiddleReleased(); return; } if (ClxG.Mouse.LeftPressed) { onLeftClicked(); return; } if (ClxG.Mouse.RightPressed) { onRightClicked(); return; } if (ClxG.Mouse.MiddlePressed) { onMiddleClicked(); return; } if (ClxG.Mouse.LeftDown) { onLeftClick(); return; } if (ClxG.Mouse.RightDown) { onRightClick(); return; } if (ClxG.Mouse.MiddleDown) { onMiddleClick(); return; } } /// <summary> /// Shows the state of the click. /// </summary> public void ShowClickState() { if (ClickState != null) { ClickState.ResetAndShow(); } } /// <summary> /// Hover event /// </summary> virtual public void onHover() { this.Color = HoverColor; } /// <summary> /// Left click event /// </summary> virtual public void onLeftClick() { this.Color = ClickColor; } /// <summary> /// Right click event /// </summary> virtual public void onRightClick() { } /// <summary> /// Middle click event /// </summary> virtual public void onMiddleClick() { } /// <summary> /// Left click event, called once per click /// </summary> virtual public void onLeftClicked() { ShowClickState(); } /// <summary> /// Right click event, called once per click /// </summary> virtual public void onRightClicked() { this.Reset(); } /// <summary> /// Middle click event, called once per click /// </summary> virtual public void onMiddleClicked() { } /// <summary> /// Ons the left released. /// </summary> virtual public void onLeftReleased() { this.Color = ClickedColor; } virtual public void onRightReleased() { } virtual public void onMiddleReleased() { } } } The issue I have is that I have all these have event styled methods, especially in ClxButton with all the onLeftClick, onRightClick, etc, etc. Is there a better way for me to handle these events to be a lot more easier for a programmer to use? I was looking at normal events on some other sites, (I'd post them but I need more rep.) and didn't really see a good way to implement delegate events into my framework. I'm not really sure how these events work, could someone possibly lay out how these events are processed for me? TL:DR * Is there a better way to handle events like this? * Are events a viable solution to this problem? Thanks in advance for any help.

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  • 64-bit Archives Needed

    - by user9154181
    A little over a year ago, we received a question from someone who was trying to build software on Solaris. He was getting errors from the ar command when creating an archive. At that time, the ar command on Solaris was a 32-bit command. There was more than 2GB of data, and the ar command was hitting the file size limit for a 32-bit process that doesn't use the largefile APIs. Even in 2011, 2GB is a very large amount of code, so we had not heard this one before. Most of our toolchain was extended to handle 64-bit sized data back in the 1990's, but archives were not changed, presumably because there was no perceived need for it. Since then of course, programs have continued to get larger, and in 2010, the time had finally come to investigate the issue and find a way to provide for larger archives. As part of that process, I had to do a deep dive into the archive format, and also do some Unix archeology. I'm going to record what I learned here, to document what Solaris does, and in the hope that it might help someone else trying to solve the same problem for their platform. Archive Format Details Archives are hardly cutting edge technology. They are still used of course, but their basic form hasn't changed in decades. Other than to fix a bug, which is rare, we don't tend to touch that code much. The archive file format is described in /usr/include/ar.h, and I won't repeat the details here. Instead, here is a rough overview of the archive file format, implemented by System V Release 4 (SVR4) Unix systems such as Solaris: Every archive starts with a "magic number". This is a sequence of 8 characters: "!<arch>\n". The magic number is followed by 1 or more members. A member starts with a fixed header, defined by the ar_hdr structure in/usr/include/ar.h. Immediately following the header comes the data for the member. Members must be padded at the end with newline characters so that they have even length. The requirement to pad members to an even length is a dead giveaway as to the age of the archive format. It tells you that this format dates from the 1970's, and more specifically from the era of 16-bit systems such as the PDP-11 that Unix was originally developed on. A 32-bit system would have required 4 bytes, and 64-bit systems such as we use today would probably have required 8 bytes. 2 byte alignment is a poor choice for ELF object archive members. 32-bit objects require 4 byte alignment, and 64-bit objects require 64-bit alignment. The link-editor uses mmap() to process archives, and if the members have the wrong alignment, we have to slide (copy) them to the correct alignment before we can access the ELF data structures inside. The archive format requires 2 byte padding, but it doesn't prohibit more. The Solaris ar command takes advantage of this, and pads ELF object members to 8 byte boundaries. Anything else is padded to 2 as required by the format. The archive header (ar_hdr) represents all numeric values using an ASCII text representation rather than as binary integers. This means that an archive that contains only text members can be viewed using tools such as cat, more, or a text editor. The original designers of this format clearly thought that archives would be used for many file types, and not just for objects. Things didn't turn out that way of course — nearly all archives contain relocatable objects for a single operating system and machine, and are used primarily as input to the link-editor (ld). Archives can have special members that are created by the ar command rather than being supplied by the user. These special members are all distinguished by having a name that starts with the slash (/) character. This is an unambiguous marker that says that the user could not have supplied it. The reason for this is that regular archive members are given the plain name of the file that was inserted to create them, and any path components are stripped off. Slash is the delimiter character used by Unix to separate path components, and as such cannot occur within a plain file name. The ar command hides the special members from you when you list the contents of an archive, so most users don't know that they exist. There are only two possible special members: A symbol table that maps ELF symbols to the object archive member that provides it, and a string table used to hold member names that exceed 15 characters. The '/' convention for tagging special members provides room for adding more such members should the need arise. As I will discuss below, we took advantage of this fact to add an alternate 64-bit symbol table special member which is used in archives that are larger than 4GB. When an archive contains ELF object members, the ar command builds a special archive member known as the symbol table that maps all ELF symbols in the object to the archive member that provides it. The link-editor uses this symbol table to determine which symbols are provided by the objects in that archive. If an archive has a symbol table, it will always be the first member in the archive, immediately following the magic number. Unlike member headers, symbol tables do use binary integers to represent offsets. These integers are always stored in big-endian format, even on a little endian host such as x86. The archive header (ar_hdr) provides 15 characters for representing the member name. If any member has a name that is longer than this, then the real name is written into a special archive member called the string table, and the member's name field instead contains a slash (/) character followed by a decimal representation of the offset of the real name within the string table. The string table is required to precede all normal archive members, so it will be the second member if the archive contains a symbol table, and the first member otherwise. The archive format is not designed to make finding a given member easy. Such operations move through the archive from front to back examining each member in turn, and run in O(n) time. This would be bad if archives were commonly used in that manner, but in general, they are not. Typically, the ar command is used to build an new archive from scratch, inserting all the objects in one operation, and then the link-editor accesses the members in the archive in constant time by using the offsets provided by the symbol table. Both of these operations are reasonably efficient. However, listing the contents of a large archive with the ar command can be rather slow. Factors That Limit Solaris Archive Size As is often the case, there was more than one limiting factor preventing Solaris archives from growing beyond the 32-bit limits of 2GB (32-bit signed) and 4GB (32-bit unsigned). These limits are listed in the order they are hit as archive size grows, so the earlier ones mask those that follow. The original Solaris archive file format can handle sizes up to 4GB without issue. However, the ar command was delivered as a 32-bit executable that did not use the largefile APIs. As such, the ar command itself could not create a file larger than 2GB. One can solve this by building ar with the largefile APIs which would allow it to reach 4GB, but a simpler and better answer is to deliver a 64-bit ar, which has the ability to scale well past 4GB. Symbol table offsets are stored as 32-bit big-endian binary integers, which limits the maximum archive size to 4GB. To get around this limit requires a different symbol table format, or an extension mechanism to the current one, similar in nature to the way member names longer than 15 characters are handled in member headers. The size field in the archive member header (ar_hdr) is an ASCII string capable of representing a 32-bit unsigned value. This places a 4GB size limit on the size of any individual member in an archive. In considering format extensions to get past these limits, it is important to remember that very few archives will require the ability to scale past 4GB for many years. The old format, while no beauty, continues to be sufficient for its purpose. This argues for a backward compatible fix that allows newer versions of Solaris to produce archives that are compatible with older versions of the system unless the size of the archive exceeds 4GB. Archive Format Differences Among Unix Variants While considering how to extend Solaris archives to scale to 64-bits, I wanted to know how similar archives from other Unix systems are to those produced by Solaris, and whether they had already solved the 64-bit issue. I've successfully moved archives between different Unix systems before with good luck, so I knew that there was some commonality. If it turned out that there was already a viable defacto standard for 64-bit archives, it would obviously be better to adopt that rather than invent something new. The archive file format is not formally standardized. However, the ar command and archive format were part of the original Unix from Bell Labs. Other systems started with that format, extending it in various often incompatible ways, but usually with the same common shared core. Most of these systems use the same magic number to identify their archives, despite the fact that their archives are not always fully compatible with each other. It is often true that archives can be copied between different Unix variants, and if the member names are short enough, the ar command from one system can often read archives produced on another. In practice, it is rare to find an archive containing anything other than objects for a single operating system and machine type. Such an archive is only of use on the type of system that created it, and is only used on that system. This is probably why cross platform compatibility of archives between Unix variants has never been an issue. Otherwise, the use of the same magic number in archives with incompatible formats would be a problem. I was able to find information for a number of Unix variants, described below. These can be divided roughly into three tribes, SVR4 Unix, BSD Unix, and IBM AIX. Solaris is a SVR4 Unix, and its archives are completely compatible with those from the other members of that group (GNU/Linux, HP-UX, and SGI IRIX). AIX AIX is an exception to rule that Unix archive formats are all based on the original Bell labs Unix format. It appears that AIX supports 2 formats (small and big), both of which differ in fundamental ways from other Unix systems: These formats use a different magic number than the standard one used by Solaris and other Unix variants. They include support for removing archive members from a file without reallocating the file, marking dead areas as unused, and reusing them when new archive items are inserted. They have a special table of contents member (File Member Header) which lets you find out everything that's in the archive without having to actually traverse the entire file. Their symbol table members are quite similar to those from other systems though. Their member headers are doubly linked, containing offsets to both the previous and next members. Of the Unix systems described here, AIX has the only format I saw that will have reasonable insert/delete performance for really large archives. Everyone else has O(n) performance, and are going to be slow to use with large archives. BSD BSD has gone through 4 versions of archive format, which are described in their manpage. They use the same member header as SVR4, but their symbol table format is different, and their scheme for long member names puts the name directly after the member header rather than into a string table. GNU/Linux The GNU toolchain uses the SVR4 format, and is compatible with Solaris. HP-UX HP-UX seems to follow the SVR4 model, and is compatible with Solaris. IRIX IRIX has 32 and 64-bit archives. The 32-bit format is the standard SVR4 format, and is compatible with Solaris. The 64-bit format is the same, except that the symbol table uses 64-bit integers. IRIX assumes that an archive contains objects of a single ELFCLASS/MACHINE, and any archive containing ELFCLASS64 objects receives a 64-bit symbol table. Although they only use it for 64-bit objects, nothing in the archive format limits it to ELFCLASS64. It would be perfectly valid to produce a 64-bit symbol table in an archive containing 32-bit objects, text files, or anything else. Tru64 Unix (Digital/Compaq/HP) Tru64 Unix uses a format much like ours, but their symbol table is a hash table, making specific symbol lookup much faster. The Solaris link-editor uses archives by examining the entire symbol table looking for unsatisfied symbols for the link, and not by looking up individual symbols, so there would be no benefit to Solaris from such a hash table. The Tru64 ld must use a different approach in which the hash table pays off for them. Widening the existing SVR4 archive symbol tables rather than inventing something new is the simplest path forward. There is ample precedent for this approach in the ELF world. When ELF was extended to support 64-bit objects, the approach was largely to take the existing data structures, and define 64-bit versions of them. We called the old set ELF32, and the new set ELF64. My guess is that there was no need to widen the archive format at that time, but had there been, it seems obvious that this is how it would have been done. The Implementation of 64-bit Solaris Archives As mentioned earlier, there was no desire to improve the fundamental nature of archives. They have always had O(n) insert/delete behavior, and for the most part it hasn't mattered. AIX made efforts to improve this, but those efforts did not find widespread adoption. For the purposes of link-editing, which is essentially the only thing that archives are used for, the existing format is adequate, and issues of backward compatibility trump the desire to do something technically better. Widening the existing symbol table format to 64-bits is therefore the obvious way to proceed. For Solaris 11, I implemented that, and I also updated the ar command so that a 64-bit version is run by default. This eliminates the 2 most significant limits to archive size, leaving only the limit on an individual archive member. We only generate a 64-bit symbol table if the archive exceeds 4GB, or when the new -S option to the ar command is used. This maximizes backward compatibility, as an archive produced by Solaris 11 is highly likely to be less than 4GB in size, and will therefore employ the same format understood by older versions of the system. The main reason for the existence of the -S option is to allow us to test the 64-bit format without having to construct huge archives to do so. I don't believe it will find much use outside of that. Other than the new ability to create and use extremely large archives, this change is largely invisible to the end user. When reading an archive, the ar command will transparently accept either form of symbol table. Similarly, the ELF library (libelf) has been updated to understand either format. Users of libelf (such as the link-editor ld) do not need to be modified to use the new format, because these changes are encapsulated behind the existing functions provided by libelf. As mentioned above, this work did not lift the limit on the maximum size of an individual archive member. That limit remains fixed at 4GB for now. This is not because we think objects will never get that large, for the history of computing says otherwise. Rather, this is based on an estimation that single relocatable objects of that size will not appear for a decade or two. A lot can change in that time, and it is better not to overengineer things by writing code that will sit and rot for years without being used. It is not too soon however to have a plan for that eventuality. When the time comes when this limit needs to be lifted, I believe that there is a simple solution that is consistent with the existing format. The archive member header size field is an ASCII string, like the name, and as such, the overflow scheme used for long names can also be used to handle the size. The size string would be placed into the archive string table, and its offset in the string table would then be written into the archive header size field using the same format "/ddd" used for overflowed names.

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  • XNA 3D model collision is inaccurate

    - by Daniel Lopez
    I am creating a classic game in 3d that deals with asteriods and you have to shoot them and avoid being hit from them. I can generate the asteroids just fine and the ship can shoot bullets just fine. But the asteroids always hit the ship even it doesn't look they are even close. I know 2D collision very well but not 3D so can someone please shed some light to my problem. Thanks in advance. Code For ModelRenderer: using System; using System.Collections.Generic; using System.Linq; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.GamerServices; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; using Microsoft.Xna.Framework.Media; namespace _3D_Asteroids { class ModelRenderer { private float aspectratio; private Model model; private Vector3 camerapos; private Vector3 modelpos; private Matrix rotationy; float radiansy = 0; private bool isalive; public ModelRenderer(Model m, float AspectRatio, Vector3 initial_pos, Vector3 initialcamerapos) { isalive = true; model = m; if (model.Meshes.Count == 0) { throw new Exception("Invalid model because it contains zero meshes!"); } modelpos = initial_pos; camerapos = initialcamerapos; aspectratio = AspectRatio; return; } public float RadiusOfSphere { get { return model.Meshes[0].BoundingSphere.Radius; } } public BoundingBox BoxBounds { get { return BoundingBox.CreateFromSphere(model.Meshes[0].BoundingSphere); } } public BoundingSphere SphereBounds { get { return model.Meshes[0].BoundingSphere; } } public Vector3 CameraPosition { set { camerapos = value; } get { return camerapos; } } public bool IsAlive { get { return isalive; } } public Vector3 ModelPosition { set { modelpos = value; } get { return modelpos; } } public void RotateY(float radians) { radiansy += radians; rotationy = Matrix.CreateRotationY(radiansy); } public Matrix RotationY { set { rotationy = value; } get { return rotationy; } } public float AspectRatio { set { aspectratio = value; } get { return aspectratio; } } public void Kill() { isalive = false; } public void Draw(float scale) { Matrix world; if (rotationy == new Matrix(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)) { world = Matrix.CreateScale(scale) * Matrix.CreateTranslation(modelpos); } else { world = rotationy * Matrix.CreateScale(scale) * Matrix.CreateTranslation(modelpos); } Matrix view = Matrix.CreateLookAt(camerapos, Vector3.Zero, Vector3.Up); Matrix projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(45.0f), this.AspectRatio, 1f, 100000f); foreach (ModelMesh mesh in model.Meshes) { foreach (BasicEffect effect in mesh.Effects) { effect.World = world; effect.View = view; effect.Projection = projection; } mesh.Draw(); } } public void Draw() { Matrix world; if (rotationy == new Matrix(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)) { world = Matrix.CreateTranslation(modelpos); } else { world = rotationy * Matrix.CreateTranslation(modelpos); } Matrix view = Matrix.CreateLookAt(camerapos, Vector3.Zero, Vector3.Up); Matrix projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(45.0f), this.AspectRatio, 1f, 100000f); foreach (ModelMesh mesh in model.Meshes) { foreach (BasicEffect effect in mesh.Effects) { effect.World = world; effect.View = view; effect.Projection = projection; } mesh.Draw(); } } } Code For Game1: using System; using System.Collections.Generic; using System.Linq; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.GamerServices; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; using Microsoft.Xna.Framework.Media; namespace _3D_Asteroids { /// <summary> /// This is the main type for your game /// </summary> public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; int score = 0, lives = 5; SpriteBatch spriteBatch; GameState gstate = GameState.OnMenuScreen; Menu menu = new Menu(Color.Yellow, Color.White); SpriteFont font; Texture2D background; ModelRenderer ship; Model b, a; List<ModelRenderer> bullets = new List<ModelRenderer>(); List<ModelRenderer> asteriods = new List<ModelRenderer>(); float time = 0.0f; int framecount = 0; SoundEffect effect; public Game1() { graphics = new GraphicsDeviceManager(this); graphics.PreferredBackBufferWidth = 1280; graphics.PreferredBackBufferHeight = 796; graphics.ApplyChanges(); Content.RootDirectory = "Content"; } /// <summary> /// Allows the game to perform any initialization it needs to before starting to run. /// This is where it can query for any required services and load any non-graphic /// related content. Calling base.Initialize will enumerate through any components /// and initialize them as well. /// </summary> protected override void Initialize() { // TODO: Add your initialization logic here base.Initialize(); } /// <summary> /// LoadContent will be called once per game and is the place to load /// all of your content. /// </summary> protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); font = Content.Load<SpriteFont>("Fonts\\Lucida Console"); background = Content.Load<Texture2D>("Textures\\B1_stars"); Model p1 = Content.Load<Model>("Models\\p1_wedge"); b = Content.Load<Model>("Models\\pea_proj"); a = Content.Load<Model>("Models\\asteroid1"); effect = Content.Load<SoundEffect>("Audio\\tx0_fire1"); ship = new ModelRenderer(p1, GraphicsDevice.Viewport.AspectRatio, new Vector3(0, 0, 0), new Vector3(0, 0, 9000)); } /// <summary> /// UnloadContent will be called once per game and is the place to unload /// all content. /// </summary> protected override void UnloadContent() { } /// <summary> /// Allows the game to run logic such as updating the world, /// checking for collisions, gathering input, and playing audio. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Update(GameTime gameTime) { KeyboardState state = Keyboard.GetState(PlayerIndex.One); switch (gstate) { case GameState.OnMenuScreen: { if (state.IsKeyDown(Keys.Enter)) { switch (menu.SelectedChoice) { case MenuChoices.Play: { gstate = GameState.GameStarted; break; } case MenuChoices.Exit: { this.Exit(); break; } } } if (state.IsKeyDown(Keys.Down)) { menu.MoveSelectedMenuChoiceDown(gameTime); } else if(state.IsKeyDown(Keys.Up)) { menu.MoveSelectedMenuChoiceUp(gameTime); } else { menu.KeysReleased(); } break; } case GameState.GameStarted: { foreach (ModelRenderer bullet in bullets) { if (bullet.ModelPosition.X < (ship.ModelPosition.X + 4000) && bullet.ModelPosition.Z < (ship.ModelPosition.X + 4000) && bullet.ModelPosition.X > (ship.ModelPosition.Z - 4000) && bullet.ModelPosition.Z > (ship.ModelPosition.Z - 4000)) { bullet.ModelPosition += (bullet.RotationY.Forward * 120); } else if (collidedwithasteriod(bullet)) { bullet.Kill(); } else { bullet.Kill(); } } foreach (ModelRenderer asteroid in asteriods) { if (ship.SphereBounds.Intersects(asteroid.BoxBounds)) { lives -= 1; asteroid.Kill(); // This always hits no matter where the ship goes. } else { asteroid.ModelPosition -= (asteroid.RotationY.Forward * 50); } } for (int index = 0; index < asteriods.Count; index++) { if (asteriods[index].IsAlive == false) { asteriods.RemoveAt(index); } } for (int index = 0; index < bullets.Count; index++) { if (bullets[index].IsAlive == false) { bullets.RemoveAt(index); } } if (state.IsKeyDown(Keys.Left)) { ship.RotateY(0.1f); if (state.IsKeyDown(Keys.Space)) { if (time < 17) { firebullet(); //effect.Play(); } } else { time = 0; } } else if (state.IsKeyDown(Keys.Right)) { ship.RotateY(-0.1f); if (state.IsKeyDown(Keys.Space)) { if (time < 17) { firebullet(); //effect.Play(); } } else { time = 0; } } else if (state.IsKeyDown(Keys.Up)) { ship.ModelPosition += (ship.RotationY.Forward * 50); if (state.IsKeyDown(Keys.Space)) { if (time < 17) { firebullet(); //effect.Play(); } } else { time = 0; } } else if (state.IsKeyDown(Keys.Space)) { time += gameTime.ElapsedGameTime.Milliseconds; if (time < 17) { firebullet(); //effect.Play(); } } else { time = 0.0f; } if ((framecount % 60) == 0) { createasteroid(); framecount = 0; } framecount++; break; } } base.Update(gameTime); } void firebullet() { if (bullets.Count < 3) { ModelRenderer bullet = new ModelRenderer(b, GraphicsDevice.Viewport.AspectRatio, ship.ModelPosition, new Vector3(0, 0, 9000)); bullet.RotationY = ship.RotationY; bullets.Add(bullet); } } void createasteroid() { if (asteriods.Count < 2) { Random random = new Random(); float z = random.Next(-13000, -11000); float x = random.Next(-9000, -8000); Random random2 = new Random(); int degrees = random.Next(0, 45); float radians = MathHelper.ToRadians(degrees); ModelRenderer asteroid = new ModelRenderer(a, GraphicsDevice.Viewport.AspectRatio, new Vector3(x, 0, z), new Vector3(0,0, 9000)); asteroid.RotateY(radians); asteriods.Add(asteroid); } } /// <summary> /// This is called when the game should draw itself. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); switch (gstate) { case GameState.OnMenuScreen: { spriteBatch.Begin(); spriteBatch.Draw(background, Vector2.Zero, Color.White); menu.DrawMenu(ref spriteBatch, font, new Vector2(GraphicsDevice.Viewport.Width / 2, GraphicsDevice.Viewport.Height / 2) - new Vector2(50f), 100f); spriteBatch.End(); break; } case GameState.GameStarted: { spriteBatch.Begin(); spriteBatch.Draw(background, Vector2.Zero, Color.White); spriteBatch.DrawString(font, "Score: " + score.ToString() + "\nLives: " + lives.ToString(), Vector2.Zero, Color.White); spriteBatch.End(); ship.Draw(); foreach (ModelRenderer bullet in bullets) { bullet.Draw(); } foreach (ModelRenderer asteroid in asteriods) { asteroid.Draw(0.1f); } break; } } base.Draw(gameTime); } bool collidedwithasteriod(ModelRenderer bullet) { foreach (ModelRenderer asteroid in asteriods) { if (bullet.SphereBounds.Intersects(asteroid.BoxBounds)) { score += 10; asteroid.Kill(); return true; } } return false; } } } }

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  • Using Image Source with big images in WPF

    - by xyzzer
    I am working on an application that allows users to manipulate multiple images by using ItemsControl. I started running some tests and found that the app has problems displaying some big images - ie. it did not work with the high resolution (21600x10800), 20MB images from http://earthobservatory.nasa.gov/Features/BlueMarble/BlueMarble_monthlies.php, though it displays the 6200x6200, 60MB Hubble telescope image from http://zebu.uoregon.edu/hudf/hudf.jpg just fine. The original solution just specified an Image control with a Source property pointing at a file on a disk (through a binding). With the Blue Marble file - the image would just not show up. Now this could be just a bug hidden somewhere deep in the funky MVVM + XAML implementation - the visual tree displayed by Snoop goes like: Window/Border/AdornerDecorator/ContentPresenter/Grid/Canvas/UserControl/Border/ContentPresenter/Grid/Grid/Grid/Grid/Border/Grid/ContentPresenter/UserControl/UserControl/Border/ContentPresenter/Grid/Grid/Grid/Grid/Viewbox/ContainerVisual/UserControl/Border/ContentPresenter/Grid/Grid/ItemsControl/Border/ItemsPresenter/Canvas/ContentPresenter/Grid/Grid/ContentPresenter/Image... Now debug this! WPF can be crazy like that... Anyway, it turned out that if I create a simple WPF application - the images load just fine. I tried finding out the root cause, but I don't want to spend weeks on it. I figured the right thing to do might be to use a converter to scale the images down - this is what I have done: ImagePath = @"F:\Astronomical\world.200402.3x21600x10800.jpg"; TargetWidth = 2800; TargetHeight = 1866; and <Image> <Image.Source> <MultiBinding Converter="{StaticResource imageResizingConverter}"> <MultiBinding.Bindings> <Binding Path="ImagePath"/> <Binding RelativeSource="{RelativeSource Self}" /> <Binding Path="TargetWidth"/> <Binding Path="TargetHeight"/> </MultiBinding.Bindings> </MultiBinding> </Image.Source> </Image> and public class ImageResizingConverter : MarkupExtension, IMultiValueConverter { public Image TargetImage { get; set; } public string SourcePath { get; set; } public int DecodeWidth { get; set; } public int DecodeHeight { get; set; } public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture) { this.SourcePath = values[0].ToString(); this.TargetImage = (Image)values[1]; this.DecodeWidth = (int)values[2]; this.DecodeHeight = (int)values[3]; return DecodeImage(); } private BitmapImage DecodeImage() { BitmapImage bi = new BitmapImage(); bi.BeginInit(); bi.DecodePixelWidth = (int)DecodeWidth; bi.DecodePixelHeight = (int)DecodeHeight; bi.UriSource = new Uri(SourcePath); bi.EndInit(); return bi; } public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture) { throw new Exception("The method or operation is not implemented."); } public override object ProvideValue(IServiceProvider serviceProvider) { return this; } } Now this works fine, except for one "little" problem. When you just specify a file path in Image.Source - the application actually uses less memory and works faster than if you use BitmapImage.DecodePixelWidth. Plus with Image.Source if you have multiple Image controls that point to the same image - they only use as much memory as if only one image was loaded. With the BitmapImage.DecodePixelWidth solution - each additional Image control uses more memory and each of them uses more than when just specifying Image.Source. Perhaps WPF somehow caches these images in compressed form while if you specify the decoded dimensions - it feels like you get an uncompressed image in memory, plus it takes 6 times the time (perhaps without it the scaling is done on the GPU?), plus it feels like the original high resolution image also gets loaded and takes up space. If I just scale the image down, save it to a temporary file and then use Image.Source to point at the file - it will probably work, but it will be pretty slow and it will require handling cleanup of the temporary file. If I could detect an image that does not get loaded properly - maybe I could only scale it down if I need to, but Image.ImageFailed never gets triggered. Maybe it has something to do with the video memory and this app just using more of it with the deep visual tree, opacity masks etc. Actual question: How can I load big images as quickly as Image.Source option does it, without using more memory for additional copies and additional memory for the scaled down image if I only need them at a certain resolution lower than original? Also, I don't want to keep them in memory if no Image control is using them anymore.

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  • Resizing pages in Adobe Acrobat Pro

    - by KP
    I am using Acrobat Professional 8 to assemble a document from two imported page images (JPGs). Acrobat seems to interpret the images at screen resolution, and creates a document that's about 35" by 46" instead of 8.5" x 11". How can I scale down the page size within Acrobat?

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  • Electronics Recycling

    - by Evan Carroll
    Is it common practice to not pay for recycling electronics? I find it kind of funny that scrap metal demands such a premium but electronics recycling gets nothing. My dad owns a stereostore and throws away hundreds of radio head-units a month is there anything useful or profitable that can be done with electronics on such a mass scale? http://stselectronicrecyclinginc.com/index.php/electronics-recycling http://www.basscomputerrecycling.com/?page_id=30 http://www.computerrecyclecenter.com/services.htm None of them seem to pay anything for the scrap.

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  • Cyberlink PowerDVD 9 on netbook

    - by marc_s
    I tried to install CyberLink's PowerDVD 9 on a friend's netbook. The installation went OK (even though the install screen is too big to fit and you can't see the "Next " buttons etc.), but once installed, PowerDVD 9 refuses to launch. It claims it requires at least 1024x768 resolution - the Acer netbook has 1024x600 :-( Any way / hack / trick to get PowerDVD9 to work anyway?? Couldn't it scale down to e.g. 800x600?

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  • linux: automount internal hard drive during boot?

    - by John Doe
    i try to create my own NAS and i need to automount the internal sata disks during boot i know i could do using fstab but im searching for a more easy/generalized way so its easier to scale with less handwork needed for every hard drive attached (or every mainboard added to the cluster) so anyone knows how to automount internal disks without using fstab like ubuntu does for usb drives? im using ubuntu server 9.10 thx all

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  • How can I replace email alerts for system events with something more scalable?

    - by Dave Forgac
    I have a number of systems and services that send email alerts when some sort of event takes place. This works fine for a small number of systems but as the number of alerts grows the important message become less visible among the informational notices. Email filtering can only be effective to a point. What sort of solution can I use in place of emails that will allow me to send arbitrary alerts from various services and that will scale easily as the number of services grows?

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  • I need Microsoft SQL Clustering/Replication/Scaling Best Practice Resources

    - by efk
    I'm trying to plan for our future scalability of our Microsoft SQL 2000/2005/2008 infrastructure. I'm having a hard time finding good information on how to best engineer such services, how to best keep these services available, and how to scale them as load increases. Can someone point me in the right direction? Books, online resources, videos, anything would be helpful.

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