// Includes
#include <windows.h>
#include <gl/gl.h>
// Function Declarations
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);
void EnableOpenGL(HWND hWnd, HDC * hDC, HGLRC * hRC);
void DisableOpenGL(HWND hWnd, HDC hDC, HGLRC hRC);
// WinMain
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPSTR lpCmdLine, int iCmdShow)
{
WNDCLASS wc;
HWND hWnd;
HDC hDC;
HGLRC hRC;
MSG msg;
BOOL quit = FALSE;
float theta = 0.0f;
// register window class
wc.style = CS_OWNDC;
wc.lpfnWndProc = WndProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInstance;
wc.hIcon = LoadIcon( NULL, IDI_APPLICATION );
wc.hCursor = LoadCursor( NULL, IDC_ARROW );
wc.hbrBackground = (HBRUSH)GetStockObject( BLACK_BRUSH );
wc.lpszMenuName = NULL;
wc.lpszClassName = "GLSample";
RegisterClass( &wc );
hWnd = CreateWindow(
"GLSample", "OpenGL Sample",
WS_CAPTION | WS_POPUPWINDOW | WS_VISIBLE,
0, 0, 1030, 1030,
NULL, NULL, hInstance, NULL );
// enable OpenGL for the window
EnableOpenGL( hWnd, &hDC, &hRC );
// Initialise random texture ID #13
const int iImageWidth13 = 64, iImageHeight13 = 64;
BYTE byImageData13[iImageWidth13 * iImageHeight13 * 3];
for(int iFill = 0; iFill < (iImageWidth13 * iImageHeight13 * 3); iFill++)
byImageData13[iFill] = rand() / 128;
glBindTexture(GL_TEXTURE_2D, 13);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB, iImageWidth13, iImageHeight13, 0, GL_RGB, GL_UNSIGNED_BYTE, byImageData13);
// Initialise random texture ID #14
const int iImageWidth14 = 64, iImageHeight14 = 64;
BYTE byImageData14[iImageWidth14 * iImageHeight14 * 3];
for(int iFill = 0; iFill < (iImageWidth14 * iImageHeight14 * 3); iFill+=3)
byImageData14[iFill] = iFill / ((iImageWidth14 * iImageHeight14 * 3) / 254);
for(int iFill = 1; iFill < (iImageWidth14 * iImageHeight14 * 3); iFill+=3)
byImageData14[iFill] = 255 - iFill / ((iImageWidth14 * iImageHeight14 * 3) / 254);
for(int iFill = 2; iFill < (iImageWidth14 * iImageHeight14 * 3); iFill+=3)
byImageData14[iFill] = abs(iFill - (iImageWidth14 * iImageHeight14 * 3) / 2) / ((iImageWidth14 * iImageHeight14 * 3) / (2*254));
glBindTexture(GL_TEXTURE_2D, 14);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB, iImageWidth14, iImageHeight14, 0, GL_RGB, GL_UNSIGNED_BYTE, byImageData14);
// Enable 2D texture mapping
glEnable(GL_TEXTURE_2D);
// program main loop
while ( !quit )
{
// check for messages
if ( PeekMessage( &msg, NULL, 0, 0, PM_REMOVE ) )
{
// handle or dispatch messages
if ( msg.message == WM_QUIT )
{
quit = TRUE;
}
else
{
TranslateMessage( &msg );
DispatchMessage( &msg );
}
}
else
{
// Map texture #14
glBindTexture (GL_TEXTURE_2D, 14);
glBegin (GL_QUADS);
glTexCoord3f (0.0, 0.0, -0.5);
glVertex3f (-0.75f,-0.75f, -0.5);
glTexCoord3f (1.0, 0.0, -0.5);
glVertex3f ( -0.4f, -0.75f, -0.5);
glTexCoord3f (1.0, 1.0, -0.5);
glVertex3f ( -0.4f, -0.4f, -0.5);
glTexCoord3f (0.0, 1.0, -0.5);
glVertex3f (-0.75f, -0.4f, -0.5);
glEnd();
// Map texture #13
glBindTexture (GL_TEXTURE_2D, 13);
glBegin (GL_QUADS);
glTexCoord3f (0.0, 0.0, -1.0);
glVertex3f (-0.5f,-0.5f, -1.0);
glTexCoord3f (1.0, 0.0, -1.0);
glVertex3f ( 0.5f, -0.5f, -1.0);
glTexCoord3f (1.0, 1.0, -1.0);
glVertex3f ( 0.5f, 0.5f, -1.0);
glTexCoord3f (0.0, 1.0, -1.0);
glVertex3f (-0.5f, 0.5f, -1.0);
glEnd();
SwapBuffers( hDC );
}
}
// shutdown OpenGL
DisableOpenGL( hWnd, hDC, hRC );
// destroy the window explicitly
DestroyWindow( hWnd );
return msg.wParam;
}
// Window Procedure
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_CREATE:
return 0;
case WM_CLOSE:
PostQuitMessage( 0 );
return 0;
case WM_DESTROY:
return 0;
case WM_KEYDOWN:
switch ( wParam )
{
case VK_ESCAPE:
PostQuitMessage(0);
return 0;
}
return 0;
default:
return DefWindowProc( hWnd, message, wParam, lParam );
}
}
// Enable OpenGL
void EnableOpenGL(HWND hWnd, HDC * hDC, HGLRC * hRC)
{
PIXELFORMATDESCRIPTOR pfd;
int format;
// get the device context (DC)
*hDC = GetDC( hWnd );
// set the pixel format for the DC
ZeroMemory( &pfd, sizeof( pfd ) );
pfd.nSize = sizeof( pfd );
pfd.nVersion = 1;
pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
pfd.iPixelType = PFD_TYPE_RGBA;
pfd.cColorBits = 24;
pfd.cDepthBits = 16;
pfd.iLayerType = PFD_MAIN_PLANE;
format = ChoosePixelFormat( *hDC, &pfd );
SetPixelFormat( *hDC, format, &pfd );
// create and enable the render context (RC)
*hRC = wglCreateContext( *hDC );
wglMakeCurrent( *hDC, *hRC );
}
// Disable OpenGL
void DisableOpenGL(HWND hWnd, HDC hDC, HGLRC hRC)
{
wglMakeCurrent( NULL, NULL );
wglDeleteContext( hRC );
ReleaseDC( hWnd, hDC );
}