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  • Why can't I make my parameter like this?

    - by mystify
    - (void)setPropertyValue:(const *void)inValue forID:(UInt32)propertyID { } The compiler doesn't like the const *void, for some reason. When I have that, it says: error: expected ')' before 'void' When I make the parameter like (UInt32)foo there is no problem. Does const *void only work in functions? I need a parameter which can be a "pointer to anything" like UInt32, Float64, etc.

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  • Templated derived class in CRTP (Curiously Recurring Template Pattern)

    - by Butterwaffle
    Hi, I have a use of the CRTP that doesn't compile with g++ 4.2.1, perhaps because the derived class is itself a template? Does anyone know why this doesn't work or, better yet, how to make it work? Sample code and the compiler error are below. Source: foo.C #include <iostream> using namespace std; template<typename X, typename D> struct foo; template<typename X> struct bar : foo<X,bar<X> > { X evaluate() { return static_cast<X>( 5.3 ); } }; template<typename X> struct baz : foo<X,baz<X> > { X evaluate() { return static_cast<X>( "elk" ); } }; template<typename X, typename D> struct foo : D { X operator() () { return static_cast<D*>(this)->evaluate(); } }; template<typename X, typename D> void print_foo( foo<X,D> xyzzx ) { cout << "Foo is " << xyzzx() << "\n"; } int main() { bar<double> br; baz<const char*> bz; print_foo( br ); print_foo( bz ); return 0; } Compiler errors foo.C: In instantiation of ‘foo<double, bar<double> >’: foo.C:8: instantiated from ‘bar<double>’ foo.C:30: instantiated from here foo.C:18: error: invalid use of incomplete type ‘struct bar<double>’ foo.C:8: error: declaration of ‘struct bar<double>’ foo.C: In instantiation of ‘foo<const char*, baz<const char*> >’: foo.C:13: instantiated from ‘baz<const char*>’ foo.C:31: instantiated from here foo.C:18: error: invalid use of incomplete type ‘struct baz<const char*>’ foo.C:13: error: declaration of ‘struct baz<const char*>’

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  • How to stable_sort without copying?

    - by Mehrdad
    Why does stable_sort need a copy constructor? (swap should suffice, right?) Or rather, how do I stable_sort a range without copying any elements? #include <algorithm> class Person { Person(Person const &); // Disable copying public: Person() : age(0) { } int age; void swap(Person &other) { using std::swap; swap(this->age, other.age); } friend void swap(Person &a, Person &b) { a.swap(b); } bool operator <(Person const &other) const { return this->age < other.age; } }; int main() { static size_t const n = 10; Person people[n]; std::stable_sort(people, people + n); }

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  • Customizing compare in bsearch()

    - by Richard Smith
    I have an array of addresses that point to integers ( these integers are sorted in ascending order). They have duplicate values. Ex: 1, 2, 2, 3, 3, 3, 3, 4, 4...... I am trying to get hold of all the values that are greater than a certain value(key). Currently trying to implement it using binary search algo - void *bsearch( const void *key, const void *base, size_t num, size_t width, int ( __cdecl *compare ) ( const void *, const void *) ); I am not able to achieve this completely, but for some of them. Would there be any other way to get hold of all the values of the array, with out changing the algorithm I am using?

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  • In ActionScript3 runtime, is there a way to get a list of all static members from a Class

    - by ty
    Let's say we have following class public class PlayerEvent extends Event { public static const PLAYER_INIT:String = "playerInit"; public static const PLAYER_MOVE:String = "playerMove"; public static const PLAYER_USE_SKILL:String = "playerUseSkill"; public function PlayerEvent(type:String) { super(type, false, true); } } } In Flash Player runtime, is there a way I can get a list of all the static members of lass PlayerEvent. Something like: trace(PlayerEvent.staticMethods) // ["PLAYER_INIT", "PLAYER_MOVE", "PLAYER_USE_SKILL"]...

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  • Parsing string based on initial format

    - by Kayla
    I'm trying to parse a set of lines and extract certain parts of the string based on an initial format (reading a configuration file). A little more explanation: the format can contain up to 4 parts to be formatted. This case, %S will skip the part, %a-%c will extract the part and will be treated as a string, %d as int. What I am trying to do now is to come up with some clever way to parse it. So far I came up with the following prototype. However, my pointer arithmetic still needs some work to skip/extract the parts. Ultimately each part will be stored on an array of structs. Such as: struct st_temp { char *parta; char *partb; char *partc; char *partd; }; ... #include <stdio.h> #include <string.h> #define DIM(x) (sizeof(x)/sizeof(*(x))) void process (const char *fmt, const char *line) { char c; const char *src = fmt; while ((c = *src++) != '\0') { if (c == 'S'); // skip part else if (c == 'a'); // extract %a else if (c == 'b'); // extract %b else if (c == 'c'); // extract %c else if (c == 'd'); // extract %d (int) else { printf("Unknown format\n"); exit(1); } } } static const char *input[] = { "bar 200.1 / / (zaz) - \"bon 10\"", "foo 100.1 / / (baz) - \"apt 20\"", }; int main (void) { const char *fmt = "%S %a / / (%b) - \"%c %d\""; size_t i; for(i = 0; i < DIM (input); i++) { process (fmt, input[i]); } return (0); }

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  • Template Syntax in C++

    - by Crystal
    I don't understand templates really and was trying to run a simple find the minimum for ints, doubles, chars. First question, why is template<typename T> sometimes used, and other times template<>? Second question, I do not know what I am doing wrong with the following code below: #include <iostream> template <typename T> T minimum(T arg1, T arg2) { return arg1 < arg2 ? arg1 : arg2; } template <typename T> // first I tried template <> instd of above, but wasn't sure the difference T minimum<const char *>(const char *arg1, const char *arg2) { return strcmp(arg1, arg2) ? arg2 : arg1; } int main() { std::cout << minimum<int>(4, 2) << '\n'; std::cout << minimum<double>(2.2, -56.7) << '\n'; std::cout << minimum(2.2, 2) << '\n'; } Compile Errors: error C2768: 'minimum' : illegal use of explicit template arguments error C2783: 'T minimum(const char *,const char *)' : could not deduce template argument for 'T' : see declaration of 'minimum' : error C2782: 'T minimum(T,T)' : template parameter 'T' is ambiguous : see declaration of 'minimum' Third, in getting familiar with separating .h and .cpp files, if I wanted this minimum() function to be a static function of my class, but it was the only function in that class, would I have to have a template class as well? I originally tried doing it that way instead of having it all in one file and I got some compile errors as well that I can't remember right now and was unsure how I would do that. Thanks!

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  • How can make a variable (not class member) "read only" in C#

    - by devfreak
    Hi, I'm new to the C# world and I can't find a method to declare read only variable in C# (something like declaring "const" variable in c++). Is there one? I'll give you an example: ... int f() { return x; } // x is not const member ... void g() { int readOnlyVar = f(); // is there a method to declare readOnlyVar as read only or const // Some code in which I want to restrict access to readOnlyVar to read only }

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  • VB Change Calulator

    - by BlueBeast
    I am creating a VB 2008 change calculator as an assignment. The program is to use the amount paid - the amount due to calculate the total.(this is working fine). After that, it is to break that amount down into dollars, quarters, dimes, nickels, and pennies. The problem I am having is that sometimes the quantity of pennies, nickels or dimes will be a negative number. For example $2.99 = 3 Dollars and -1 Pennies. SOLVED Thanks to the responses, here is what I was able to make work with my limited knowledge. Option Explicit On Option Strict Off Option Infer Off Public Class frmMain Private Sub btnClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClear.Click 'Clear boxes lblDollarsAmount.Text = String.Empty lblQuartersAmount.Text = String.Empty lblDimesAmount.Text = String.Empty lblNickelsAmount.Text = String.Empty lblPenniesAmount.Text = String.Empty txtOwed.Text = String.Empty txtPaid.Text = String.Empty lblAmountDue.Text = String.Empty txtOwed.Focus() End Sub Private Sub btnExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnExit.Click 'Close application' Me.Close() End Sub Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click ' Find Difference between Total Price and Total Received lblAmountDue.Text = Val(txtPaid.Text) - Val(txtOwed.Text) Dim intChangeAmount As Integer = lblAmountDue.Text * 100 'Declare Integers Dim intDollarsBack As Integer Dim intQuartersBack As Integer Dim intDimesBack As Integer Dim intNickelsBack As Integer Dim intPenniesBack As Integer ' Change Values Const intDollarValue As Integer = 100 Const intQuarterValue As Integer = 25 Const intDimeValue As Integer = 10 Const intNickelValue As Integer = 5 Const intPennyValue As Integer = 1 'Dollars intDollarsBack = CInt(Val(intChangeAmount \ intDollarValue)) intChangeAmount = intChangeAmount - Val(Val(intDollarsBack) * intDollarValue) lblDollarsAmount.Text = intDollarsBack.ToString 'Quarters intQuartersBack = CInt(Val(intChangeAmount \ intQuarterValue)) intChangeAmount = intChangeAmount - Val(Val(intQuartersBack) * intQuarterValue) lblQuartersAmount.Text = intQuartersBack.ToString 'Dimes intDimesBack = CInt(Val(intChangeAmount \ intDimeValue)) intChangeAmount = intChangeAmount - Val(Val(intDimesBack) * intDimeValue) lblDimesAmount.Text = intDimesBack.ToString 'Nickels intNickelsBack = CInt(Val(intChangeAmount \ intNickelValue)) intChangeAmount = intChangeAmount - Val(Val(intNickelsBack) * intNickelValue) lblNickelsAmount.Text = intNickelsBack.ToString 'Pennies intPenniesBack = CInt(Val(intChangeAmount \ intPennyValue)) intChangeAmount = intChangeAmount - Val(Val(intPenniesBack) * intPennyValue) lblPenniesAmount.Text = intPenniesBack.ToString End Sub End Class

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  • Why does gcc warn about incompatible struct assignment with a `self = [super initDesignatedInit];' c

    - by gavinbeatty
    I have the following base/derived class setup in Objective-C: @interface ASCIICodeBase : NSObject { @protected char code_[4]; } - (Base *)initWithASCIICode:(const char *)code; @end @implementation ASCIICodeBase - (ASCIICodeBase *)initWithCode:(const char *)code len:(size_t)len { if (len == 0 || len > 3) { return nil; } if (self = [super init]) { memset(code_, 0, 4); strncpy(code_, code, 3); } return self; } @end @interface CountryCode : ASCIICodeBase - (CountryCode *)initWithCode:(const char *)code; @end @implementation CountryCode - (CountryCode *)initWithCode:(const char *)code { size_t len = strlen(code); if (len != 2) { return nil; } self = [super initWithCode:code len:len]; // here return self; } @end On the line marked "here", I get the following gcc warning: warning: incompatible Objective-C types assigning 'struct ASCIICodeBase *', expected 'struct CurrencyCode *' Is there something wrong with this code or should I have the ASCIICodeBase return id? Or maybe use a cast on the "here" line?

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  • Particle and Physics problem.

    - by Quincy
    This was originally a forum post so I hope you guys don't mind it being 2 questions in one. I am making a game and I got some basic physics implemented. I have 2 problems, 1 with particles being drawn in the wrong place and one with going through walls while jumping in corners. Skip over to about 15 sec video showing the 2 problems : http://youtube.com/watch?v=Tm9nfWsWfiM So the problem with the particles seems to be coming from the removal, as soon as I remove that piece of code it instantly works, but there shouldn't be a problem since they shouldn't even draw when their energy gets to 0 (and then they get removed) So my first question is, how are these particles getting warped all over the screen ? Relevant code : Particle class : class Particle { //Physics public Vector2 position = new Vector2(0,0); public float direction = 180; public float speed = 100; public float energy = 1; protected float startEnergy = 1; //Visual public Sprite sprite; public float rotation = 0; public float scale = 1; public byte alpha = 255; public BlendMode blendMode { get { return sprite.BlendMode; } set { sprite.BlendMode = value; } } public Particle() { } public virtual void Think(float frameTime) { if (energy - frameTime < 0) energy = 0; else energy -= frameTime; position += new Vector2((float)Math.Cos(MathHelper.DegToRad(direction)), (float)Math.Sin(MathHelper.DegToRad(direction))) * speed * frameTime; alpha = (byte)(255 * energy / startEnergy); sprite.Rotation = rotation; sprite.Position = position; sprite.Color = new Color(sprite.Color.R, sprite.Color.G, sprite.Color.B, alpha); } public virtual void Draw(float frameTime) { if (energy > 0) { World.camera.DrawSprite(sprite); } } // Basic particle implementation class BasicSprite : Particle { public BasicSprite(Sprite _sprite) { sprite = _sprite; } } Emitter : class Emitter { protected static Random rand = new Random(); protected List<Particle> particles = new List<Particle>(); public BaseEntity target = null; public Vector2 position = new Vector2(0, 0); public bool Active = true; public float timeAlive = 0; public int particleCount = 0; public int ParticlesPerSeccond { get { return (int)(1 / particleSpawnTime); } set { particleSpawnTime = 1 / (float)value; } } public float dieTime = float.MaxValue; float particleSpawnTime = 0.05f; float spawnTime = 0; public Emitter() { } public virtual void Think(float frametime) { spawnTime += frametime; if (dieTime != float.MaxValue) { timeAlive += frametime; if (timeAlive >= dieTime) Active = false; } if (Active) { if (target != null) position = target.Position; while (spawnTime > particleSpawnTime) { spawnTime -= particleSpawnTime; AddParticle(); particleCount++; } } for (int i = 0; i < particles.Count; i++) { particles[i].Think(frametime); if (particles[i].energy <= 0) { particles.Remove(particles[i]); // As soon as this is removed, it works particleCount--; } } } public virtual void AddParticle() { } public virtual void Draw(float frametime) { foreach (Particle particle in particles) { particle.Draw(frametime); } } } class BloodEmitter : Emitter { Image image; public BloodEmitter() { image = new Image(@"Content/Particles/TinyCircle.png"); image.CreateMaskFromColor(new Color(255, 0, 255, 255)); this.dieTime = 0.5f; this.ParticlesPerSeccond = 100; } public override void AddParticle() { Sprite sprite = new Sprite(image); sprite.Color = new Color((byte)(rand.NextDouble() * 255), (byte)(rand.NextDouble() * 255), (byte)(rand.NextDouble() * 255)); BasicSprite particle = new BasicSprite(sprite); particle.direction = (float)rand.NextDouble() * 360; particle.position = position; particle.blendMode = BlendMode.Alpha; particles.Add(particle); } } The seccond problem is the physics problem, for some reason I can get through the right bottom corner while jumping. I think this is coming from me switching animations but I thought I made it compensate for that. Relevant code : PhysicsEntity : class PhysicsEntity : BaseEntity { // Horizontal movement constants protected const float maxHorizontalSpeed = 1000; protected const float horizontalAcceleration = 15; protected const float horizontalDragAir = 0.95f; protected const float horizontalDragGround = 0.95f; // Vertical movement constants protected const float maxVerticalSpeed = 1000; protected const float verticalAcceleration = 20; // Everything needed for movement and correct animations protected float movement = 0; protected bool onGround = false; protected Vector2 Velocity = new Vector2(0, 0); protected float maxSpeed = 0; float lastThink = 0; float thinkTime = 1f/60f; public PhysicsEntity(Vector2 position, Sprite sprite) : base(position, sprite) { } public override void Draw(float frameTime) { base.Draw(frameTime); } public override void Think(float frameTime) { CalculateMovement(frameTime); base.Think(frameTime); } protected void CalculateMovement(float frameTime) { lastThink += frameTime; while (lastThink > thinkTime) { onGround = false; Velocity.X = MathHelper.Clamp(Velocity.X + horizontalAcceleration * movement, -maxHorizontalSpeed, maxHorizontalSpeed); if (onGround) Velocity.X *= horizontalDragGround; else Velocity.X *= horizontalDragAir; if (maxSpeed < Velocity.X) maxSpeed = Velocity.X; Velocity.Y = MathHelper.Clamp(Velocity.Y + verticalAcceleration, -maxVerticalSpeed, maxVerticalSpeed); lastThink -= thinkTime; DoCollisions(thinkTime); DoAnimations(thinkTime); } } public virtual void DoAnimations(float frameTime) { } public void DoCollisions(float frameTime) { Position.Y += Velocity.Y * frameTime; Vector2 tileCollision = GetTileCollision(); if (tileCollision.X != -1 || tileCollision.Y != -1) { Vector2 collisionDepth = CollisionRectangle.DepthIntersection( new Rectangle( tileCollision.X * World.tileEngine.TileWidth, tileCollision.Y * World.tileEngine.TileHeight, World.tileEngine.TileWidth, World.tileEngine.TileHeight ) ); Position.Y += collisionDepth.Y; if (collisionDepth.Y < 0) onGround = true; Velocity.Y = 0; } Position.X += Velocity.X * frameTime; tileCollision = GetTileCollision(); if (tileCollision.X != -1 || tileCollision.Y != -1) { Vector2 collisionDepth = CollisionRectangle.DepthIntersection( new Rectangle( tileCollision.X * World.tileEngine.TileWidth, tileCollision.Y * World.tileEngine.TileHeight, World.tileEngine.TileWidth, World.tileEngine.TileHeight ) ); Position.X += collisionDepth.X; Velocity.X = 0; } } public void DoCollisions(Vector2 difference) { CollisionRectangle.Y = Position.Y - difference.Y; CollisionRectangle.Height += difference.Y; Vector2 tileCollision = GetTileCollision(); if (tileCollision.X != -1 || tileCollision.Y != -1) { Vector2 collisionDepth = CollisionRectangle.DepthIntersection( new Rectangle( tileCollision.X * World.tileEngine.TileWidth, tileCollision.Y * World.tileEngine.TileHeight, World.tileEngine.TileWidth, World.tileEngine.TileHeight ) ); Position.Y += collisionDepth.Y; if (collisionDepth.Y < 0) onGround = true; Velocity.Y = 0; } CollisionRectangle.X = Position.X - difference.X; CollisionRectangle.Width += difference.X; tileCollision = GetTileCollision(); if (tileCollision.X != -1 || tileCollision.Y != -1) { Vector2 collisionDepth = CollisionRectangle.DepthIntersection( new Rectangle( tileCollision.X * World.tileEngine.TileWidth, tileCollision.Y * World.tileEngine.TileHeight, World.tileEngine.TileWidth, World.tileEngine.TileHeight ) ); Position.X += collisionDepth.X; Velocity.X = 0; } } Vector2 GetTileCollision() { int topLeftTileX = (int)(CollisionRectangle.TopLeft.X / World.tileEngine.TileWidth); int topLeftTileY = (int)(CollisionRectangle.TopLeft.Y / World.tileEngine.TileHeight); int BottomRightTileX = (int)(CollisionRectangle.DownRight.X / World.tileEngine.TileWidth); int BottomRightTileY = (int)(CollisionRectangle.DownRight.Y / World.tileEngine.TileHeight); if (CollisionRectangle.DownRight.Y % World.tileEngine.TileHeight == 0) // If your exactly against the tile don't count that as being inside the tile BottomRightTileY -= 1; if (CollisionRectangle.DownRight.X % World.tileEngine.TileWidth == 0) // If your exactly against the tile don't count that as being inside the tile BottomRightTileX -= 1; for (int i = topLeftTileX; i <= BottomRightTileX; i++) { for (int j = topLeftTileY; j <= BottomRightTileY; j++) { if (World.tileEngine.TileIsSolid(i, j)) { return new Vector2(i, j); } } } return new Vector2(-1, -1); } } Player : enum State { Standing, Running, Jumping, Falling, Sliding, WallSlide } class Player : PhysicsEntity { private State state { get { return currentState; } set { if (currentState != value) { currentState = value; animationChanged = true; } } } private State currentState = State.Standing; private BasicEmitter basicEmitter = new BasicEmitter(); public bool flipped; public bool animationChanged = false; protected const float jumpPower = 600; AnimationManager animationManager; Rectangle DrawRectangle; public override Rectangle CollisionRectangle { get { return new Rectangle( Position.X - DrawRectangle.Width / 2f, Position.Y - DrawRectangle.Height / 2f, DrawRectangle.Width, DrawRectangle.Height ); } } public Player(Vector2 position, Sprite sprite) : base(position, sprite) { // Only posted the relevant bit DrawRectangle = animationManager.currentAnimation.drawingRectangle; } public override void Draw(float frameTime) { World.camera.DrawSprite( Sprite, Position + new Vector2(DrawRectangle.X, DrawRectangle.Y), animationManager.currentAnimation.drawingRectangle ); } public override void Think(float frameTime) { //I only posted the relevant stuff if (animationChanged) { // if the animation has changed make sure we compensate for the change in with and height animationChanged = false; DoCollisions(animationManager.getSizeDifference()); } DoCustomMovement(); base.Think(frameTime); if (!onGround && Velocity.Y > 0) { state = State.Falling; } } void DoCustomMovement() { if (onGround) { if (World.renderWindow.Input.IsKeyDown(KeyCode.W)) { Velocity.Y = -jumpPower; state = State.Jumping; } } } public override void DoAnimations(float frameTime) { string stateName = Enum.GetName(typeof(State), state); if (!animationManager.currentAnimationIs(stateName)) { animationManager.PlayAnimation(stateName); } animationManager.Think(frameTime); DrawRectangle = animationManager.currentAnimation.drawingRectangle; Sprite.Center = new Vector2( DrawRectangle.X + DrawRectangle.Width / 2, DrawRectangle.Y + DrawRectangle.Height / 2 ); Sprite.FlipX(flipped); } So why am I warping through walls ? I have given this some thought but I just can't seem to find out why this is happening. Full source if needed : source : http://www.mediafire.com/?rc7ddo09gnr68zd (download link)

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  • Powershell script to change screen Orientation

    - by user161964
    I wrote a script to change Primary screen orientation to portrait. my screen is 1920X1200 It runs and no error reported. But the screen does not rotated as i expected. The code was modified from Set-ScreenResolution (Andy Schneider) Does anybody can help me take a look? some reference site: 1.set-screenresolution http://gallery.technet.microsoft.com/ScriptCenter/2a631d72-206d-4036-a3f2-2e150f297515/ 2.C code for change oridentation (MSDN) Changing Screen Orientation Programmatically http://msdn.microsoft.com/en-us/library/ms812499.aspx my code as below: Function Set-ScreenOrientation { $pinvokeCode = @" using System; using System.Runtime.InteropServices; namespace Resolution { [StructLayout(LayoutKind.Sequential)] public struct DEVMODE1 { [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)] public string dmDeviceName; public short dmSpecVersion; public short dmDriverVersion; public short dmSize; public short dmDriverExtra; public int dmFields; public short dmOrientation; public short dmPaperSize; public short dmPaperLength; public short dmPaperWidth; public short dmScale; public short dmCopies; public short dmDefaultSource; public short dmPrintQuality; public short dmColor; public short dmDuplex; public short dmYResolution; public short dmTTOption; public short dmCollate; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)] public string dmFormName; [MarshalAs(UnmanagedType.U4)] public short dmDisplayOrientation public short dmLogPixels; public short dmBitsPerPel; public int dmPelsWidth; public int dmPelsHeight; public int dmDisplayFlags; public int dmDisplayFrequency; public int dmICMMethod; public int dmICMIntent; public int dmMediaType; public int dmDitherType; public int dmReserved1; public int dmReserved2; public int dmPanningWidth; public int dmPanningHeight; }; class User_32 { [DllImport("user32.dll")] public static extern int EnumDisplaySettings(string deviceName, int modeNum, ref DEVMODE1 devMode); [DllImport("user32.dll")] public static extern int ChangeDisplaySettings(ref DEVMODE1 devMode, int flags); public const int ENUM_CURRENT_SETTINGS = -1; public const int CDS_UPDATEREGISTRY = 0x01; public const int CDS_TEST = 0x02; public const int DISP_CHANGE_SUCCESSFUL = 0; public const int DISP_CHANGE_RESTART = 1; public const int DISP_CHANGE_FAILED = -1; } public class PrmaryScreenOrientation { static public string ChangeOrientation() { DEVMODE1 dm = GetDevMode1(); if (0 != User_32.EnumDisplaySettings(null, User_32.ENUM_CURRENT_SETTINGS, ref dm)) { dm.dmDisplayOrientation = DMDO_90 dm.dmPelsWidth = 1200; dm.dmPelsHeight = 1920; int iRet = User_32.ChangeDisplaySettings(ref dm, User_32.CDS_TEST); if (iRet == User_32.DISP_CHANGE_FAILED) { return "Unable To Process Your Request. Sorry For This Inconvenience."; } else { iRet = User_32.ChangeDisplaySettings(ref dm, User_32.CDS_UPDATEREGISTRY); switch (iRet) { case User_32.DISP_CHANGE_SUCCESSFUL: { return "Success"; } case User_32.DISP_CHANGE_RESTART: { return "You Need To Reboot For The Change To Happen.\n If You Feel Any Problem After Rebooting Your Machine\nThen Try To Change Resolution In Safe Mode."; } default: { return "Failed"; } } } } else { return "Failed To Change."; } } private static DEVMODE1 GetDevMode1() { DEVMODE1 dm = new DEVMODE1(); dm.dmDeviceName = new String(new char[32]); dm.dmFormName = new String(new char[32]); dm.dmSize = (short)Marshal.SizeOf(dm); return dm; } } } "@ Add-Type $pinvokeCode -ErrorAction SilentlyContinue [Resolution.PrmaryScreenOrientation]::ChangeOrientation() }

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  • Is this kind of Design by Contract useless?

    - by Charlie Pigarelli
    I've just started informatics university and I'm attending a programming course about C(++). The programming professor prefers to teach very few things (in 3 month we have just reached the functions topic) and connect every topic with a type of programming design that somehow is similar to the Design by Contract design. Basically what he ask us to do is to write every exercise with comments Pre-conditions, Post-conditions and Invariants that should prove the correctness of each program we write. But this doesn't make any sense to me. I mean, ok: maybe writing down your thoughts prevent you from doing some mistakes, but if this is all an abstract thing, then if your program intuition is wrong you'll write your program wrong and then you'll also write pre and post conditions wrong probably auto convincing your self about its correctness. Most of the time, both me and other students have written programs that seemed ok and that had correct pre and post condition too. But at the moment of testing it was just completely wrong. I had some experience before this course of programming and I had written a lot of line of code before and I found myself comfortably with just writing a program and unit test it. It take less time to accomplish and is less "abstract" than just thinking about what every single piece of your program should do in every case (which is kinda like mentally testing it). Finally, all this pre and post conditions takes me like 80% of the total time of the exercise. It's harder to think about putting down this pre and post correct than to write the program itself. Since we are like the only course of the only university probably in the entire world that makes this things, could someone please tell me how should I manage this thing? Am I right thinking that this doesn't worth anything? Should I change university? (there are like double of the people attending that course and it seems that usually very few people passes the exam the first year). Should I convince myself it's method is right?

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  • How to obtain a random sub-datatable from another data table

    - by developerit
    Introduction In this article, I’ll show how to get a random subset of data from a DataTable. This is useful when you already have queries that are filtered correctly but returns all the rows. Analysis I came across this situation when I wanted to display a random tag cloud. I already had the query to get the keywords ordered by number of clicks and I wanted to created a tag cloud. Tags that are the most popular should have more chance to get picked and should be displayed larger than less popular ones. Implementation In this code snippet, there is everything you need. ' Min size, in pixel for the tag Private Const MIN_FONT_SIZE As Integer = 9 ' Max size, in pixel for the tag Private Const MAX_FONT_SIZE As Integer = 14 ' Basic function that retreives Tags from a DataBase Public Shared Function GetTags() As MediasTagsDataTable ' Simple call to the TableAdapter, to get the Tags ordered by number of clicks Dim dt As MediasTagsDataTable = taMediasTags.GetDataValide ' If the query returned no result, return an empty DataTable If dt Is Nothing OrElse dt.Rows.Count < 1 Then Return New MediasTagsDataTable End If ' Set the font-size of the group of data ' We are dividing our results into sub set, according to their number of clicks ' Example: 10 results -> [0,2] will get font size 9, [3,5] will get font size 10, [6,8] wil get 11, ... ' This is the number of elements in one group Dim groupLenth As Integer = CType(Math.Floor(dt.Rows.Count / (MAX_FONT_SIZE - MIN_FONT_SIZE)), Integer) ' Counter of elements in the same group Dim counter As Integer = 0 ' Counter of groups Dim groupCounter As Integer = 0 ' Loop througt the list For Each row As MediasTagsRow In dt ' Set the font-size in a custom column row.c_FontSize = MIN_FONT_SIZE + groupCounter ' Increment the counter counter += 1 ' If the group counter is less than the counter If groupLenth <= counter Then ' Start a new group counter = 0 groupCounter += 1 End If Next ' Return the new DataTable with font-size Return dt End Function ' Function that generate the random sub set Public Shared Function GetRandomSampleTags(ByVal KeyCount As Integer) As MediasTagsDataTable ' Get the data Dim dt As MediasTagsDataTable = GetTags() ' Create a new DataTable that will contains the random set Dim rep As MediasTagsDataTable = New MediasTagsDataTable ' Count the number of row in the new DataTable Dim count As Integer = 0 ' Random number generator Dim rand As New Random() While count < KeyCount Randomize() ' Pick a random row Dim r As Integer = rand.Next(0, dt.Rows.Count - 1) Dim tmpRow As MediasTagsRow = dt(r) ' Import it into the new DataTable rep.ImportRow(tmpRow) ' Remove it from the old one, to be sure not to pick it again dt.Rows.RemoveAt(r) ' Increment the counter count += 1 End While ' Return the new sub set Return rep End Function Pro’s This method is good because it doesn’t require much work to get it work fast. It is a good concept when you are working with small tables, let says less than 100 records. Con’s If you have more than 100 records, out of memory exception may occur since we are coping and duplicating rows. I would consider using a stored procedure instead.

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  • IrrKlang with Ogre

    - by Vinnie
    I'm trying to set up sound in my Ogre3D project. I have installed irrKlang 1.4.0 and added it's include and lib directories to my projects VC++ Include and Library directories, but I'm still getting a Linker error when I attempt to build. Any suggestions? (Error 4007 error LNK2019: unresolved external symbol "__declspec(dllimport) class irrklang::ISoundEngine * __cdecl irrklang::createIrrKlangDevice(enum irrklang::E_SOUND_OUTPUT_DRIVER,int,char const *,char const *)" (_imp?createIrrKlangDevice@irrklang@@YAPAVISoundEngine@1@W4E_SOUND_OUTPUT_DRIVER@1@HPBD1@Z) referenced in function "public: __thiscall SoundManager::SoundManager(void)" (??0SoundManager@@QAE@XZ)

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  • What does this piece of code in C++ mean? [closed]

    - by user1838418
    const double pi = 3.141592653589793; const angle rightangle = pi/2; inline angle deg2rad(angle degree) { return degree * rightangle / 90.; } angle function1() { return rightangle * ( ((double) rand()) / ((double) RAND_MAX) - .5 ); } bool setmargin(angle theta, angle phi, angle margin) { return (theta > phi-margin && theta < phi+margin); } Please help me. I'm new to C++

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  • GLSL compiler messages from different vendors [on hold]

    - by revers
    I'm writing a GLSL shader editor and I want to parse GLSL compiler messages to make hyperlinks to invalid lines in a shader code. I know that these messages are vendor specific but currently I have access only to AMD's video cards. I want to handle at least NVidia's and Intel's hardware, apart from AMD's. If you have video card from different vendor than AMD, could you please give me the output of following C++ program: #include <GL/glew.h> #include <GL/freeglut.h> #include <iostream> using namespace std; #define STRINGIFY(X) #X static const char* fs = STRINGIFY( out vec4 out_Color; mat4 m; void main() { vec3 v3 = vec3(1.0); vec2 v2 = v3; out_Color = vec4(5.0 * v2.x, 1.0); vec3 k = 3.0; float = 5; } ); static const char* vs = STRINGIFY( in vec3 in_Position; void main() { vec3 v(5); gl_Position = vec4(in_Position, 1.0); } ); void printShaderInfoLog(GLint shader) { int infoLogLen = 0; int charsWritten = 0; GLchar *infoLog; glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLogLen); if (infoLogLen > 0) { infoLog = new GLchar[infoLogLen]; glGetShaderInfoLog(shader, infoLogLen, &charsWritten, infoLog); cout << "Log:\n" << infoLog << endl; delete [] infoLog; } } void printProgramInfoLog(GLint program) { int infoLogLen = 0; int charsWritten = 0; GLchar *infoLog; glGetProgramiv(program, GL_INFO_LOG_LENGTH, &infoLogLen); if (infoLogLen > 0) { infoLog = new GLchar[infoLogLen]; glGetProgramInfoLog(program, infoLogLen, &charsWritten, infoLog); cout << "Program log:\n" << infoLog << endl; delete [] infoLog; } } void initShaders() { GLuint v = glCreateShader(GL_VERTEX_SHADER); GLuint f = glCreateShader(GL_FRAGMENT_SHADER); GLint vlen = strlen(vs); GLint flen = strlen(fs); glShaderSource(v, 1, &vs, &vlen); glShaderSource(f, 1, &fs, &flen); GLint compiled; glCompileShader(v); bool succ = true; glGetShaderiv(v, GL_COMPILE_STATUS, &compiled); if (!compiled) { cout << "Vertex shader not compiled." << endl; succ = false; } printShaderInfoLog(v); glCompileShader(f); glGetShaderiv(f, GL_COMPILE_STATUS, &compiled); if (!compiled) { cout << "Fragment shader not compiled." << endl; succ = false; } printShaderInfoLog(f); GLuint p = glCreateProgram(); glAttachShader(p, v); glAttachShader(p, f); glLinkProgram(p); glUseProgram(p); printProgramInfoLog(p); if (!succ) { exit(-1); } delete [] vs; delete [] fs; } int main(int argc, char* argv[]) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA); glutInitWindowSize(600, 600); glutCreateWindow("Triangle Test"); glewInit(); GLenum err = glewInit(); if (GLEW_OK != err) { cout << "glewInit failed, aborting." << endl; exit(1); } cout << "Using GLEW " << glewGetString(GLEW_VERSION) << endl; const GLubyte* renderer = glGetString(GL_RENDERER); const GLubyte* vendor = glGetString(GL_VENDOR); const GLubyte* version = glGetString(GL_VERSION); const GLubyte* glslVersion = glGetString(GL_SHADING_LANGUAGE_VERSION); GLint major, minor; glGetIntegerv(GL_MAJOR_VERSION, &major); glGetIntegerv(GL_MINOR_VERSION, &minor); cout << "GL Vendor : " << vendor << endl; cout << "GL Renderer : " << renderer << endl; cout << "GL Version : " << version << endl; cout << "GL Version : " << major << "." << minor << endl; cout << "GLSL Version : " << glslVersion << endl; initShaders(); return 0; } On my video card it gives: Status: Using GLEW 1.7.0 GL Vendor : ATI Technologies Inc. GL Renderer : ATI Radeon HD 4250 GL Version : 3.3.11631 Compatibility Profile Context GL Version : 3.3 GLSL Version : 3.30 Vertex shader not compiled. Log: Vertex shader failed to compile with the following errors: ERROR: 0:1: error(#132) Syntax error: '5' parse error ERROR: error(#273) 1 compilation errors. No code generated Fragment shader not compiled. Log: Fragment shader failed to compile with the following errors: WARNING: 0:1: warning(#402) Implicit truncation of vector from size 3 to size 2. ERROR: 0:1: error(#174) Not enough data provided for construction constructor WARNING: 0:1: warning(#402) Implicit truncation of vector from size 1 to size 3. ERROR: 0:1: error(#132) Syntax error: '=' parse error ERROR: error(#273) 2 compilation errors. No code generated Program log: Vertex and Fragment shader(s) were not successfully compiled before glLinkProgram() was called. Link failed. Or if you like, you could give me other compiler messages than proposed by me. To summarize, the question is: What are GLSL compiler messages formats (INFOs, WARNINGs, ERRORs) for different vendors? Please give me examples or pattern explanation. EDIT: Ok, it seems that this question is too broad, then shortly: How does NVidia's and Intel's GLSL compilers present ERROR and WARNING messages? AMD/ATI uses patterns like this: ERROR: <position>:<line_number>: <message> WARNING: <position>:<line_number>: <message> (examples are above).

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  • Why is Double.Parse so slow?

    - by alexhildyard
    I was recently investigating a bottleneck in one of my applications, which read a CSV file from disk using a TextReader a line at a time, split the tokens, called Double.Parse on each one, then shunted the results into an object list. I was surprised to find it was actually the Double.Parse which seemed to be taking up most of the time.Googling turned up this, which is a little unfocused in places but throws out some excellent ideas:It makes more sense to work with binary format directly, rather than coerce strings into doublesThere is a significant performance improvement in composing doubles directly from the byte stream via long intermediariesString.Split is inefficient on fixed length recordsIn fact it turned out that my problem was more insidious and also more mundane -- a simple case of bad data in, bad data out. Since I had been serialising my Doubles as strings, when I inadvertently divided by zero and produced a "NaN", this of course was serialised as well without error. And because I was reading in using Double.Parse, these "NaN" fields were also (correctly) populating real Double objects without error. The issue is that Double.Parse("NaN") is incredibly slow. In fact, it is of the order of 2000x slower than parsing a valid double. For example, the code below gave me results of 357ms to parse 1000 NaNs, versus 15ms to parse 100,000 valid doubles.            const int invalid_iterations = 1000;            const int valid_iterations = invalid_iterations * 100;            const string invalid_string = "NaN";            const string valid_string = "3.14159265";            DateTime start = DateTime.Now;                        for (int i = 0; i < invalid_iterations; i++)            {                double invalid_double = Double.Parse(invalid_string);            }            Console.WriteLine(String.Format("{0} iterations of invalid double, time taken (ms): {1}",                invalid_iterations,                ((TimeSpan)DateTime.Now.Subtract(start)).Milliseconds            ));            start = DateTime.Now;            for (int i = 0; i < valid_iterations; i++)            {                double valid_double = Double.Parse(valid_string);            }            Console.WriteLine(String.Format("{0} iterations of valid double, time taken (ms): {1}",                valid_iterations,                ((TimeSpan)DateTime.Now.Subtract(start)).Milliseconds            )); I think the moral is to look at the context -- specifically the data -- as well as the code itself. Once I had corrected my data, the performance of Double.Parse was perfectly acceptable, and while clearly it could have been improved, it was now sufficient to my needs.

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  • C++11 Tidbits: Decltype (Part 2, trailing return type)

    - by Paolo Carlini
    Following on from last tidbit showing how the decltype operator essentially queries the type of an expression, the second part of this overview discusses how decltype can be syntactically combined with auto (itself the subject of the March 2010 tidbit). This combination can be used to specify trailing return types, also known informally as "late specified return types". Leaving aside the technical jargon, a simple example from section 8.3.5 of the C++11 standard usefully introduces this month's topic. Let's consider a template function like: template <class T, class U> ??? foo(T t, U u) { return t + u; } The question is: what should replace the question marks? The problem is that we are dealing with a template, thus we don't know at the outset the types of T and U. Even if they were restricted to be arithmetic builtin types, non-trivial rules in C++ relate the type of the sum to the types of T and U. In the past - in the GNU C++ runtime library too - programmers used to address these situations by way of rather ugly tricks involving __typeof__ which now, with decltype, could be rewritten as: template <class T, class U> decltype((*(T*)0) + (*(U*)0)) foo(T t, U u) { return t + u; } Of course the latter is guaranteed to work only for builtin arithmetic types, eg, '0' must make sense. In short: it's a hack. On the other hand, in C++11 you can use auto: template <class T, class U> auto foo(T t, U u) -> decltype(t + u) { return t + u; } This is much better. It's generic and a construct fully supported by the language. Finally, let's see a real-life example directly taken from the C++11 runtime library as implemented in GCC: template<typename _IteratorL, typename _IteratorR> inline auto operator-(const reverse_iterator<_IteratorL>& __x, const reverse_iterator<_IteratorR>& __y) -> decltype(__y.base() - __x.base()) { return __y.base() - __x.base(); } By now it should appear be completely straightforward. The availability of trailing return types in C++11 allowed fixing a real bug in the C++98 implementation of this operator (and many similar ones). In GCC, C++98 mode, this operator is: template<typename _IteratorL, typename _IteratorR> inline typename reverse_iterator<_IteratorL>::difference_type operator-(const reverse_iterator<_IteratorL>& __x, const reverse_iterator<_IteratorR>& __y) { return __y.base() - __x.base(); } This was guaranteed to work well with heterogeneous reverse_iterator types only if difference_type was the same for both types.

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  • returning a heap block by reference in c++

    - by basicR
    I was trying to brush up my c++ skills. I got 2 functions: concat_HeapVal() returns the output heap variable by value concat_HeapRef() returns the output heap variable by reference When main() runs it will be on stack,s1 and s2 will be on stack, I pass the value by ref only and in each of the below functions, I create a variable on heap and concat them. When concat_HeapVal() is called it returns me the correct output. When concat_HeapRef() is called it returns me some memory address (wrong output). Why? I use new operator in both the functions. Hence it allocates on heap. So when I return by reference, heap will still be VALID even when my main() stack memory goes out of scope. So it's left to OS to cleanup the memory. Right? string& concat_HeapRef(const string& s1, const string& s2) { string *temp = new string(); temp->append(s1); temp->append(s2); return *temp; } string* concat_HeapVal(const string& s1, const string& s2) { string *temp = new string(); temp->append(s1); temp->append(s2); return temp; } int main() { string s1,s2; string heapOPRef; string *heapOPVal; cout<<"String Conact Experimentations\n"; cout<<"Enter s-1 : "; cin>>s1; cout<<"Enter s-2 : "; cin>>s2; heapOPRef = concat_HeapRef(s1,s2); heapOPVal = concat_HeapVal(s1,s2); cout<<heapOPRef<<" "<<heapOPVal<<" "<<endl; return -9; }

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  • How should game objects be aware of each other?

    - by Jefffrey
    I find it hard to find a way to organize game objects so that they are polymorphic but at the same time not polymorphic. Here's an example: assuming that we want all our objects to update() and draw(). In order to do that we need to define a base class GameObject which have those two virtual pure methods and let polymorphism kicks in: class World { private: std::vector<GameObject*> objects; public: // ... update() { for (auto& o : objects) o->update(); for (auto& o : objects) o->draw(window); } }; The update method is supposed to take care of whatever state the specific class object needs to update. The fact is that each objects needs to know about the world around them. For example: A mine needs to know if someone is colliding with it A soldier should know if another team's soldier is in proximity A zombie should know where the closest brain, within a radius, is For passive interactions (like the first one) I was thinking that the collision detection could delegate what to do in specific cases of collisions to the object itself with a on_collide(GameObject*). Most of the the other informations (like the other two examples) could just be queried by the game world passed to the update method. Now the world does not distinguish objects based on their type (it stores all object in a single polymorphic container), so what in fact it will return with an ideal world.entities_in(center, radius) is a container of GameObject*. But of course the soldier does not want to attack other soldiers from his team and a zombie doesn't case about other zombies. So we need to distinguish the behavior. A solution could be the following: void TeamASoldier::update(const World& world) { auto list = world.entities_in(position, eye_sight); for (const auto& e : list) if (auto enemy = dynamic_cast<TeamBSoldier*>(e)) // shoot towards enemy } void Zombie::update(const World& world) { auto list = world.entities_in(position, eye_sight); for (const auto& e : list) if (auto enemy = dynamic_cast<Human*>(e)) // go and eat brain } but of course the number of dynamic_cast<> per frame could be horribly high, and we all know how slow dynamic_cast can be. The same problem also applies to the on_collide(GameObject*) delegate that we discussed earlier. So what it the ideal way to organize the code so that objects can be aware of other objects and be able to ignore them or take actions based on their type?

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  • Keep Getting Syntax Error C2199?

    - by DARK3ZOOZ
    Here's my problem I'm trying to define something, but keep getting a syntax error Code: #define R_RegisterShader 0x50C8A0 int (*trap_R_RegisterShader)( const char *name, int Arg_1 ) = (int (_cdecl *)(const char *, int ))R_RegisterShader; ^^^^^^^ This last part is where I keep getting the error if you need more lines of codes, just let me know. thanks http://gyazo.com/1a47ebc12cfbd6ea72feb72c686ae84d screenshot of error

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  • The way I think about Diagnostic tools

    - by Daniel Moth
    Every software has issues, or as we like to call them "bugs". That is not a discussion point, just a mere fact. It follows that an important skill for developers is to be able to diagnose issues in their code. Of course we need to advance our tools and techniques so we can prevent bugs getting into the code (e.g. unit testing), but beyond designing great software, diagnosing bugs is an equally important skill. To diagnose issues, the most important assets are good techniques, skill, experience, and maybe talent. What also helps is having good diagnostic tools and what helps further is knowing all the features that they offer and how to use them. The following classification is how I like to think of diagnostics. Note that like with any attempt to bucketize anything, you run into overlapping areas and blurry lines. Nevertheless, I will continue sharing my generalizations ;-) It is important to identify at the outset if you are dealing with a performance or a correctness issue. If you have a performance issue, use a profiler. I hear people saying "I am using the debugger to debug a performance issue", and that is fine, but do know that a dedicated profiler is the tool for that job. Just because you don't need them all the time and typically they cost more plus you are not as familiar with them as you are with the debugger, doesn't mean you shouldn't invest in one and instead try to exclusively use the wrong tool for the job. Visual Studio has a profiler and a concurrency visualizer (for profiling multi-threaded apps). If you have a correctness issue, then you have several options - that's next :-) This is how I think of identifying a correctness issue Do you want a tool to find the issue for you at design time? The compiler is such a tool - it gives you an exact list of errors. Compilers now also offer warnings, which is their way of saying "this may be an error, but I am not smart enough to know for sure". There are also static analysis tools, which go a step further than the compiler in identifying issues in your code, sometimes with the aid of code annotations and other times just by pointing them at your raw source. An example is FxCop and much more in Visual Studio 11 Code Analysis. Do you want a tool to find the issue for you with code execution? Just like static tools, there are also dynamic analysis tools that instead of statically analyzing your code, they analyze what your code does dynamically at runtime. Whether you have to setup some unit tests to invoke your code at runtime, or have to manually run your app (and interact with it) under the tool, or have to use a script to execute your binary under the tool… that varies. The result is still a list of issues for you to address after the analysis is complete or a pause of the execution when the first issue is encountered. If a code path was not taken, no analysis for it will exist, obviously. An example is the GPU Race detection tool that I'll be talking about on the C++ AMP team blog. Another example is the MSR concurrency CHESS tool. Do you want you to find the issue at design time using a tool? Perform a code walkthrough on your own or with colleagues. There are code review tools that go beyond just diffing sources, and they help you with that aspect too. For example, there is a new one in Visual Studio 11 and searching with my favorite search engine yielded this article based on the Developer Preview. Do you want you to find the issue with code execution? Use a debugger - let’s break this down further next. This is how I think of debugging: There is post mortem debugging. That means your code has executed and you did something in order to examine what happened during its execution. This can vary from manual printf and other tracing statements to trace events (e.g. ETW) to taking dumps. In all cases, you are left with some artifact that you examine after the fact (after code execution) to discern what took place hoping it will help you find the bug. Learn how to debug dump files in Visual Studio. There is live debugging. I will elaborate on this in a separate post, but this is where you inspect the state of your program during its execution, and try to find what the problem is. More from me in a separate post on live debugging. There is a hybrid of live plus post-mortem debugging. This is for example what tools like IntelliTrace offer. If you are a tools vendor interested in the diagnostics space, it helps to understand where in the above classification your tool excels, where its primary strength is, so you can market it as such. Then it helps to see which of the other areas above your tool touches on, and how you can make it even better there. Finally, see what areas your tool doesn't help at all with, and evaluate whether it should or continue to stay clear. Even though the classification helps us think about this space, the reality is that the best tools are either extremely excellent in only one of this areas, or more often very good across a number of them. Another approach is to offer a toolset covering all areas, with appropriate integration and hand off points from one to the other. Anyway, with that brain dump out of the way, in follow-up posts I will dive into live debugging, and specifically live debugging in Visual Studio - stay tuned if that interests you. Comments about this post by Daniel Moth welcome at the original blog.

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  • file doesn't open, running outside of debugger results in seg fault (c++)

    - by misterich
    Hello (and thanks in advance) I'm in a bit of a quandry, I cant seem to figure out why I'm seg faulting. A couple of notes: It's for a course -- and sadly I am required to use use C-strings instead of std::string. Please dont fix my code (I wont learn that way and I will keep bugging you). please just point out the flaws in my logic and suggest a different function/way. platform: gcc version 4.4.1 on Suse Linux 11.2 (2.6.31 kernel) Here's the code main.cpp: // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C/C++ Std Library) #include <cstdlib> /// EXIT_SUCCESS, EXIT_FAILURE #include <iostream> /// cin, cout, ifstream #include <cassert> /// assert // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "dict.h" /// Header for the dictionary class // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR CONSTANTS #define ENTER '\n' /// Used to accept new lines, quit program. #define SPACE ' ' /// One way to end the program // /////////////////////////////////////////////////////////////////////////////////// // CUSTOM DATA TYPES /// File Namespace -- keep it local namespace { /// Possible program prompts to display for the user. enum FNS_Prompts { fileName_, /// prints out the name of the file noFile_, /// no file was passed to the program tooMany_, /// more than one file was passed to the program noMemory_, /// Not enough memory to use the program usage_, /// how to use the program word_, /// ask the user to define a word. notFound_, /// the word is not in the dictionary done_, /// the program is closing normally }; } // /////////////////////////////////////////////////////////////////////////////////// // Namespace using namespace std; /// Nothing special in the way of namespaces // /////////////////////////////////////////////////////////////////////////////////// // FUNCTIONS /** prompt() prompts the user to do something, uses enum Prompts for parameter. */ void prompt(FNS_Prompts msg /** determines the prompt to use*/) { switch(msg) { case fileName_ : { cout << ENTER << ENTER << "The file name is: "; break; } case noFile_ : { cout << ENTER << ENTER << "...Sorry, a dictionary file is needed. Try again." << endl; break; } case tooMany_ : { cout << ENTER << ENTER << "...Sorry, you can only specify one dictionary file. Try again." << endl; break; } case noMemory_ : { cout << ENTER << ENTER << "...Sorry, there isn't enough memory available to run this program." << endl; break; } case usage_ : { cout << "USAGE:" << endl << " lookup.exe [dictionary file name]" << endl << endl; break; } case done_ : { cout << ENTER << ENTER << "like Master P says, \"Word.\"" << ENTER << endl; break; } case word_ : { cout << ENTER << ENTER << "Enter a word in the dictionary to get it's definition." << ENTER << "Enter \"?\" to get a sorted list of all words in the dictionary." << ENTER << "... Press the Enter key to quit the program: "; break; } case notFound_ : { cout << ENTER << ENTER << "...Sorry, that word is not in the dictionary." << endl; break; } default : { cout << ENTER << ENTER << "something passed an invalid enum to prompt(). " << endl; assert(false); /// something passed in an invalid enum } } } /** useDictionary() uses the dictionary created by createDictionary * - prompts user to lookup a word * - ends when the user enters an empty word */ void useDictionary(Dictionary &d) { char *userEntry = new char; /// user's input on the command line if( !userEntry ) // check the pointer to the heap { cout << ENTER << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } do { prompt(word_); // test code cout << endl << "----------------------------------------" << endl << "Enter something: "; cin.getline(userEntry, INPUT_LINE_MAX_LEN, ENTER); cout << ENTER << userEntry << endl; }while ( userEntry[0] != NIL && userEntry[0] != SPACE ); // GARBAGE COLLECTION delete[] userEntry; } /** Program Entry * Reads in the required, single file from the command prompt. * - If there is no file, state such and error out. * - If there is more than one file, state such and error out. * - If there is a single file: * - Create the database object * - Populate the database object * - Prompt the user for entry * main() will return EXIT_SUCCESS upon termination. */ int main(int argc, /// the number of files being passed into the program char *argv[] /// pointer to the filename being passed into tthe program ) { // EXECUTE /* Testing code * / char tempFile[INPUT_LINE_MAX_LEN] = {NIL}; cout << "enter filename: "; cin.getline(tempFile, INPUT_LINE_MAX_LEN, '\n'); */ // uncomment after successful debugging if(argc <= 1) { prompt(noFile_); prompt(usage_); return EXIT_FAILURE; /// no file was passed to the program } else if(argc > 2) { prompt(tooMany_); prompt(usage_); return EXIT_FAILURE; /// more than one file was passed to the program } else { prompt(fileName_); cout << argv[1]; // print out name of dictionary file if( !argv[1] ) { prompt(noFile_); prompt(usage_); return EXIT_FAILURE; /// file does not exist } /* file.open( argv[1] ); // open file numEntries >> in.getline(file); // determine number of dictionary objects to create file.close(); // close file Dictionary[ numEntries ](argv[1]); // create the dictionary object */ // TEMPORARY FILE FOR TESTING!!!! //Dictionary scrabble(tempFile); Dictionary scrabble(argv[1]); // creaate the dicitonary object //*/ useDictionary(scrabble); // prompt the user, use the dictionary } // exit return EXIT_SUCCESS; /// terminate program. } Dict.h/.cpp #ifndef DICT_H #define DICT_H // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (Custom header files) #include "entry.h" /// class for dictionary entries // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define INPUT_LINE_MAX_LEN 256 /// Maximum length of each line in the dictionary file class Dictionary { public : // // Do NOT modify the public section of this class // typedef void (*WordDefFunc)(const char *word, const char *definition); Dictionary( const char *filename ); ~Dictionary(); const char *lookupDefinition( const char *word ); void forEach( WordDefFunc func ); private : // // You get to provide the private members // // VARIABLES int m_numEntries; /// stores the number of entries in the dictionary Entry *m_DictEntry_ptr; /// points to an array of class Entry // Private Functions }; #endif ----------------------------------- // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C/C++ Std Library) #include <iostream> /// cout, getline #include <fstream> // ifstream #include <cstring> /// strchr // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "dict.h" /// Header file required by assignment //#include "entry.h" /// Dicitonary Entry Class // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define COMMA ',' /// Delimiter for file #define ENTER '\n' /// Carriage return character #define FILE_ERR_MSG "The data file could not be opened. Program will now terminate." #pragma warning(disable : 4996) /// turn off MS compiler warning about strcpy() // /////////////////////////////////////////////////////////////////////////////////// // Namespace reference using namespace std; // /////////////////////////////////////////////////////////////////////////////////// // PRIVATE MEMBER FUNCTIONS /** * Sorts the dictionary entries. */ /* static void sortDictionary(?) { // sort through the words using qsort } */ /** NO LONGER NEEDED?? * parses out the length of the first cell in a delimited cell * / int getWordLength(char *str /// string of data to parse ) { return strcspn(str, COMMA); } */ // /////////////////////////////////////////////////////////////////////////////////// // PUBLIC MEMBER FUNCTIONS /** constructor for the class * - opens/reads in file * - creates initializes the array of member vars * - creates pointers to entry objects * - stores pointers to entry objects in member var * - ? sort now or later? */ Dictionary::Dictionary( const char *filename ) { // Create a filestream, open the file to be read in ifstream dataFile(filename, ios::in ); /* if( dataFile.fail() ) { cout << FILE_ERR_MSG << endl; exit(EXIT_FAILURE); } */ if( dataFile.is_open() ) { // read first line of data // TEST CODE in.getline(dataFile, INPUT_LINE_MAX_LEN) >> m_numEntries; // TEST CODE char temp[INPUT_LINE_MAX_LEN] = {NIL}; // TEST CODE dataFile.getline(temp,INPUT_LINE_MAX_LEN,'\n'); dataFile >> m_numEntries; /** Number of terms in the dictionary file * \todo find out how many lines in the file, subtract one, ingore first line */ //create the array of entries m_DictEntry_ptr = new Entry[m_numEntries]; // check for valid memory allocation if( !m_DictEntry_ptr ) { cout << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } // loop thru each line of the file, parsing words/def's and populating entry objects for(int EntryIdx = 0; EntryIdx < m_numEntries; ++EntryIdx) { // VARIABLES char *tempW_ptr; /// points to a temporary word char *tempD_ptr; /// points to a temporary def char *w_ptr; /// points to the word in the Entry object char *d_ptr; /// points to the definition in the Entry int tempWLen; /// length of the temp word string int tempDLen; /// length of the temp def string char tempLine[INPUT_LINE_MAX_LEN] = {NIL}; /// stores a single line from the file // EXECUTE // getline(dataFile, tempLine) // get a "word,def" line from the file dataFile.getline(tempLine, INPUT_LINE_MAX_LEN); // get a "word,def" line from the file // Parse the string tempW_ptr = tempLine; // point the temp word pointer at the first char in the line tempD_ptr = strchr(tempLine, COMMA); // point the def pointer at the comma *tempD_ptr = NIL; // replace the comma with a NIL ++tempD_ptr; // increment the temp def pointer // find the string lengths... +1 to account for terminator tempWLen = strlen(tempW_ptr) + 1; tempDLen = strlen(tempD_ptr) + 1; // Allocate heap memory for the term and defnition w_ptr = new char[ tempWLen ]; d_ptr = new char[ tempDLen ]; // check memory allocation if( !w_ptr && !d_ptr ) { cout << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } // copy the temp word, def into the newly allocated memory and terminate the strings strcpy(w_ptr,tempW_ptr); w_ptr[tempWLen] = NIL; strcpy(d_ptr,tempD_ptr); d_ptr[tempDLen] = NIL; // set the pointers for the entry objects m_DictEntry_ptr[ EntryIdx ].setWordPtr(w_ptr); m_DictEntry_ptr[ EntryIdx ].setDefPtr(d_ptr); } // close the file dataFile.close(); } else { cout << ENTER << FILE_ERR_MSG << endl; exit(EXIT_FAILURE); } } /** * cleans up dynamic memory */ Dictionary::~Dictionary() { delete[] m_DictEntry_ptr; /// thou shalt not have memory leaks. } /** * Looks up definition */ /* const char *lookupDefinition( const char *word ) { // print out the word ---- definition } */ /** * prints out the entire dictionary in sorted order */ /* void forEach( WordDefFunc func ) { // to sort before or now.... that is the question } */ Entry.h/cpp #ifndef ENTRY_H #define ENTRY_H // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C++ Std lib) #include <cstdlib> /// EXIT_SUCCESS, NULL // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define NIL '\0' /// C-String terminator #define MEM_ERR_MSG "Memory allocation has failed. Program will now terminate." // /////////////////////////////////////////////////////////////////////////////////// // CLASS DEFINITION class Entry { public: Entry(void) : m_word_ptr(NULL), m_def_ptr(NULL) { /* default constructor */ }; void setWordPtr(char *w_ptr); /// sets the pointer to the word - only if the pointer is empty void setDefPtr(char *d_ptr); /// sets the ponter to the definition - only if the pointer is empty /// returns what is pointed to by the word pointer char getWord(void) const { return *m_word_ptr; } /// returns what is pointed to by the definition pointer char getDef(void) const { return *m_def_ptr; } private: char *m_word_ptr; /** points to a dictionary word */ char *m_def_ptr; /** points to a dictionary definition */ }; #endif -------------------------------------------------- // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "entry.h" /// class header file // /////////////////////////////////////////////////////////////////////////////////// // PUBLIC FUNCTIONS /* * only change the word member var if it is in its initial state */ void Entry::setWordPtr(char *w_ptr) { if(m_word_ptr == NULL) { m_word_ptr = w_ptr; } } /* * only change the def member var if it is in its initial state */ void Entry::setDefPtr(char *d_ptr) { if(m_def_ptr == NULL) { m_word_ptr = d_ptr; } }

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  • Deep Cloning C++ class that inherits CCNode in Cocos2dx

    - by A Devanney
    I stuck with something in Cocos2dx ... I'm trying to deep clone one of my classes that inherits CCNode. Basically i have.... GameItem* pTemp = new GameItem(*_actualItem); // loops through all the blocks in gameitem and updates their position pTemp->moveDown(); // if in boundary or collision etc... if (_gameBoard->isValidMove(pTemp)) { _actualItem = pTemp; // display the position CCLog("pos (1) --- (X : %d,Y : %d)", _actualItem->getGridX(),_actualItem->getGridY()); } Then doesn't work, because the gameitem inherits CCNode and has the collection of another class that also inherits CCNode. its just creating a shallow copy and when you look at children of the gameitem node in the copy, just point to the original? class GameItem : public CCNode { // maps to the actual grid position of the shape CCPoint* _rawPosition; // tracks the current grid position int _gridX, _gridY; // tracks the change if the item has moved CCPoint _offset; public: //constructors GameItem& operator=(const GameItem& item); GameItem(Shape shape); ... } then in the implementation.... GameItem& GameItem::operator=(const GameItem& item) { _gridX = item.getGridX(); _gridY = item.getGridY(); _offset = item.getOffSet(); _rawPosition = item.getRawPosition(); // how do i copy the node? return *this; } // shape contains an array of position for the game character GameItem::GameItem(Shape shape) { _rawPosition = shape.getShapePositions(); //loop through all blocks in position for (int i = 0; i < 7; i++) { // get the position of the first block in the shape and add to the position of the first block int x = (int) (getRawPosition()[i].x + getGridX()); int y = (int) (getRawPosition()[i].y + getGridY()); //instantiate a block with the position and type Block* block = Block::blockWithFile(x,y,(i+1), shape); // add the block to the this node this->addChild(block); } } And for clarity here is the block class class Block : public CCNode{ private: // using composition over inheritance CCSprite* _sprite; // tracks the current grid position int _gridX, _gridY; // used to store actual image number int _blockNo; public: Block(void); Block(int gridX, int gridY, int blockNo); Block& operator=(const Block& block); // static constructor for the creation of a block static Block* blockWithFile(int gridX, int gridY,int blockNo, Shape shape); ... } The blocks implementation..... Block& Block::operator=(const Block& block) { _sprite = new CCSprite(*block._sprite); _gridX = block._gridX; _gridY = block._gridY; _blockNo = block._blockNo; //again how to clone CCNode? return *this; } Block* Block::blockWithFile(int gridX, int gridY,int blockNo, Shape shape) { Block* block = new Block(); if (block && block->initBlockWithFile(gridX, gridY,blockNo, shape)) { block->autorelease(); return block; } CC_SAFE_DELETE(block); return NULL; } bool Block::initBlockWithFile(int gridX, int gridY,int blockNo, Shape shape) { setGridX(gridX); setGridY(gridY); setBlockNo(blockNo); const char* characterImg = helperFunctions::Format(shape.getFileName(),blockNo); // add to the spritesheet CCTexture2D* gameArtTexture = CCTextureCache::sharedTextureCache()->addImage("Character.pvr.ccz"); CCSpriteBatchNode::createWithTexture(gameArtTexture); // block settings _sprite = CCSprite::createWithSpriteFrameName(characterImg); // set the position of the block and add it to the layer this->setPosition(CONVERTGRIDTOACTUALPOS_X_Y(gridX,gridY)); this->addChild(_sprite); return true; } Any ideas are welcome at this point!! thanks

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