Fast Animation with the Windows GDI

Here's a speed test :) mine stays at about 480fps with only 2-3% CPU.

Another really nice effect using this method :icon_smile:

Got it working with objects and bitmaps, I think with some optimizations I could use this to make some neat games :)

p->r = unsigned char(((cos(px + frameOffset * 10) / sin(py + frameOffset)) * cos(frameOffset * 3) * 10) * 127 + 127);
      p->g = ~p->r;

was error in my DEV C++

Sorry, I should have tested it with multiple compilers, replace that line with:

p->r = (unsigned char)(((cos(px + frameOffset * 10) / sin(py + frameOffset)) * cos(frameOffset * 3) * 10) * 127 + 127);

and it should work.

Pretty cool. Looks something someone will see if they were high of drugs.

Pretty cool. Looks something someone will see if they were high of drugs.

Haha, what have you been smoking? I'd go crazy if anything turned out that intense.
Thanks alot for the feedback :icon_razz:

Issues when building with mingw:

main.cpp:12: error: ISO C++ prohibits anonymous structs
main.cpp: In function `void onFrame(pixel*)':
main.cpp:60: error: expected primary-expression before "unsigned"
main.cpp:60: error: expected `;' before "unsigned"
main.cpp: In function `void MakeSurface(HWND__*)':
main.cpp:134: warning: passing NULL used for non-pointer converting 2 of `void* CreateThread(_SECURITY_ATTRIBUTES*, DWORD, DWORD (*)(void*), void*, DWORD, DWORD*)'
main.cpp:134: warning: passing NULL used for non-pointer converting 5 of `void* CreateThread(_SECURITY_ATTRIBUTES*, DWORD, DWORD (*)(void*), void*, DWORD, DWORD*)'
main.cpp: In function `int WinMain(HINSTANCE__*, HINSTANCE__*, CHAR*, int)':
main.cpp:237: warning: passing NULL used for non-pointer converting 4 of `BOOL GetMessageA(tagMSG*, HWND__*, UINT, UINT)'

This includes the cast you've already corrected. So it's mostly just that anonymous struct you may want to look at.

[edit]Also, the necessary library to link with:

-LD:\Programs\CodeBlocks\MinGW\lib -lgdi32

Where the path to the library will be whatever your install might be.

This includes the cast you've already corrected. So it's mostly just that anonymous struct you may want to look at.

Does giving the anonymous structure a name fix that?
Never thought there would be so many compiler issues, and I didn't realize that anonymous structs weren't allowed.

Thanks :)

Does giving the anonymous structure a name fix that?

Yup. I just named it s , for example.

Hi, thanks for the cool code. I got it working in a Win32 app (project type choice) in VC++ Express 2010 by making the includes:
#include "stdafx.h"
#include "GDIWin32.h"
#include <windows.h>
#include <iostream>
#include <cmath>

and putting the L in front of the quoted text, as in:
// Init wc
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.cbSize = sizeof( WNDCLASSEX );
wc.hbrBackground = CreateSolidBrush( 0 );
wc.hCursor = LoadCursor( NULL, IDC_ARROW );
wc.hIcon = LoadIcon( NULL, IDI_APPLICATION );
wc.hIconSm = LoadIcon( NULL, IDI_APPLICATION );
wc.hInstance = hInstance;
wc.lpfnWndProc = WndProc;
wc.lpszClassName = L"animation_class";
wc.lpszMenuName = NULL;
wc.style = 0;

// Register wc
if ( !RegisterClassEx(&wc) ) {
MessageBox( NULL, L"Failed to register window class.", L"Error", MB_OK );
return 0;
}

Very cool, thanks very much. Any thoughts on how this could be implemented in a Windows Forms Application? (Sorry if this is a really stupid question, just starting in VC++.) Thanks again, Bill

Finally got around to putting this animation code into a Visual C++ 2010 Express Windows form application. To use it, start a new form build, add a PictureBox, name it "src" and make it some even dimension like 400,400. Add a button, name it "btnStart", text to "Start", add a timer to the form, set it to 20ms and disabled.
Add the attached code.

void DrawMath(void){
           // Create a new bitmap.
   Bitmap^ bmp = gcnew Bitmap(src->Size.Width,src->Size.Height);
   //bmp->PixelFormat=Format32bppArgb;
   // Lock the bitmap's bits.  
   Rectangle rect = Rectangle(0,0,src->Size.Width,src->Size.Height);
   System::Drawing::Imaging::BitmapData^ bmpData = bmp->LockBits( rect, System::Drawing::Imaging::ImageLockMode::ReadWrite, bmp->PixelFormat );

   // Get the address of the first line.
   IntPtr ptr = bmpData->Scan0;

   // Declare an array to hold the bytes of the bitmap.
   // This code is specific to a bitmap with 24 bits per pixels.
   int bytes = bmpData->Stride * bmp->Height;
   array<Byte>^rgbValues = gcnew array<Byte>(bytes);
   array<Byte>^rgbValues1;
   rgbValues1 = rgbValues;

   // Copy the RGB values into the array.

  // This is where all the drawing takes place


  // +0.005 each frame
  static double frameOffset = 0;

  double px; // % of the way across the bitmap
  double py; // % of the way down the bitmap
  double mycosoff;
  int width = src->Size.Width;
  int height = src->Size.Height;
  double frame10 = (10.0) * frameOffset;
  double cosoff = (1270) * cos(frameOffset * 3);
  double pyinc = (1.0) / double(height);
  int counter=0;
  for (int x = 0; x < width; ++x) {
    px = double(x) / double(width);
    mycosoff = cos(px + frame10) * cosoff;
    int ywidth=x;
    py=pyinc+frameOffset;
    for (int y = 0; y < height; ++y ) {
      unsigned char red = unsigned char(((mycosoff / sin(py))) + 127);
      rgbValues[counter++] = 0xff;
      rgbValues[counter++] = red;
      rgbValues[counter++] = ~red;
      rgbValues[counter++] = 0xff;
      ywidth+= width;
      py+=pyinc; 
    }
  }

  frameOffset += 0.005;

   // Copy the RGB values back to the bitmap
   System::Runtime::InteropServices::Marshal::Copy( rgbValues1, 0, ptr, bytes );

   // Unlock the bits.
   bmp->UnlockBits( bmpData );

   // Draw the modified image.
   //e->Graphics->DrawImage( bmp, 0, 150 );
        src->Image = bmp;
        src->Invalidate();
}
#pragma endregion
    private: System::Void timer1_Tick(System::Object^  sender, System::EventArgs^  e) {
                 DrawMath();
             }
    private: System::Void btnStart_Click(System::Object^  sender, System::EventArgs^  e) {
                 static int OnOff=0;
                 if (OnOff==0){
                     btnStart->Text = L"Stop";
                     timer1->Enabled = true;
                     OnOff=1;
                 }
                 else{
                     btnStart->Text = L"Start";
                     timer1->Enabled = false;
                     OnOff=0;
                 }

             }

Have fun! THANKS AGAIN FOR POSTING THE FAST ANIMATION SNIPPET!

Hi,
And this is a C Sharp version from Bill Dreschel's code. The picture box I used named 'pictureBox1'. It looks pretty good.
I post this here because I found this article while I was searching for a CSharp solution about something like this.
And I think it may help someone like me :-)

static double frameOffset = 0;
private void Draw()
{
    var bmp = new Bitmap(pictureBox1.Width, pictureBox1.Height);
    var drawingRect = new Rectangle(0, 0, pictureBox1.Width, pictureBox1.Height);
    var bmpData = bmp.LockBits(drawingRect, ImageLockMode.ReadWrite, bmp.PixelFormat);

    // Get the address of the first line.
    IntPtr ptr = bmpData.Scan0;

    // Declare an array to hold the bytes of the bitmap.
    // This code is specific to a bitmap with 24 bits per pixels.
    int bytes = bmpData.Stride*bmp.Height;
    Byte[] rgbValues = new Byte[bytes];
    Byte[] rgbValues1;
    rgbValues1 = rgbValues;


    // Copy the RGB values into the array.
    // This is where all the drawing takes place
    // +0.005 each frame

    double px; // % of the way across the bitmap
    double py; // % of the way down the bitmap
    double mycosoff;
    int width = pictureBox1.Width;
    int height = pictureBox1.Height;
    double frame10 = (10.0) * frameOffset;
    double cosoff = (1270) * Math.Cos(frameOffset*3);
    double pyinc = (1.0)/height;
    int counter = 0;
    for (int x = 0; x < width; ++x)
    {
        px = (double) x/width;
        mycosoff = Math.Cos(px + frame10)*cosoff;
        int ywidth = x;
        py = pyinc + frameOffset;
        for (int y = 0; y < height; ++y)
        {
            int red = (int) ((mycosoff/Math.Sin(py))) + 127;
            rgbValues[counter++] = 0xff;
            rgbValues[counter++] = (byte) red;
            rgbValues[counter++] = (byte) ~red;
            rgbValues[counter++] = 0xff;
            ywidth += width;
            py += pyinc;
        }
    }

    frameOffset += 0.005;
    // Copy the RGB values back to the bitmap
    System.Runtime.InteropServices.Marshal.Copy(rgbValues1, 0, ptr, bytes);
    // Unlock the bits.
    bmp.UnlockBits(bmpData);
    // Draw the modified image.
    //e->Graphics->DrawImage( bmp, 0, 150 );
    pictureBox1.Image = bmp;
    pictureBox1.Invalidate();
}

private void timer1_Tick(object sender, EventArgs e)
{
    Draw();
}