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#include <windows.h>
#include <GL/gl.h>
char *className = "OpenGL";
char *windowName = "OpenGL Cube";
int winX = 0, winY = 0;
int winWidth = 300, winHeight = 300;
HDC hDC;
HGLRC hGLRC;
HPALETTE hPalette;
void
init(void)
{
/* set viewing projection */
glMatrixMode(GL_PROJECTION);
glFrustum(-0.5F, 0.5F, -0.5F, 0.5F, 1.0F, 3.0F);
/* position viewer */
glMatrixMode(GL_MODELVIEW);
glTranslatef(0.0F, 0.0F, -2.0F);
/* position object */
glRotatef(30.0F, 1.0F, 0.0F, 0.0F);
glRotatef(30.0F, 0.0F, 1.0F, 0.0F);
glEnable(GL_DEPTH_TEST);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
}
void
redraw(void)
{
/* clear color and depth buffers */
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
/* draw six faces of a cube */
glBegin(GL_QUADS);
glNormal3f( 0.0F, 0.0F, 1.0F);
glVertex3f( 0.5F, 0.5F, 0.5F); glVertex3f(-0.5F, 0.5F, 0.5F);
glVertex3f(-0.5F,-0.5F, 0.5F); glVertex3f( 0.5F,-0.5F, 0.5F);
glNormal3f( 0.0F, 0.0F,-1.0F);
glVertex3f(-0.5F,-0.5F,-0.5F); glVertex3f(-0.5F, 0.5F,-0.5F);
glVertex3f( 0.5F, 0.5F,-0.5F); glVertex3f( 0.5F,-0.5F,-0.5F);
glNormal3f( 0.0F, 1.0F, 0.0F);
glVertex3f( 0.5F, 0.5F, 0.5F); glVertex3f( 0.5F, 0.5F,-0.5F);
glVertex3f(-0.5F, 0.5F,-0.5F); glVertex3f(-0.5F, 0.5F, 0.5F);
glNormal3f( 0.0F,-1.0F, 0.0F);
glVertex3f(-0.5F,-0.5F,-0.5F); glVertex3f( 0.5F,-0.5F,-0.5F);
glVertex3f( 0.5F,-0.5F, 0.5F); glVertex3f(-0.5F,-0.5F, 0.5F);
glNormal3f( 1.0F, 0.0F, 0.0F);
glVertex3f( 0.5F, 0.5F, 0.5F); glVertex3f( 0.5F,-0.5F, 0.5F);
glVertex3f( 0.5F,-0.5F,-0.5F); glVertex3f( 0.5F, 0.5F,-0.5F);
glNormal3f(-1.0F, 0.0F, 0.0F);
glVertex3f(-0.5F,-0.5F,-0.5F); glVertex3f(-0.5F,-0.5F, 0.5F);
glVertex3f(-0.5F, 0.5F, 0.5F); glVertex3f(-0.5F, 0.5F,-0.5F);
glEnd();
SwapBuffers(hDC);
}
void
resize(void)
{
/* set viewport to cover the window */
glViewport(0, 0, winWidth, winHeight);
}
void
setupPixelFormat(HDC hDC)
{
PIXELFORMATDESCRIPTOR pfd = {
sizeof(PIXELFORMATDESCRIPTOR), /* size */
1, /* version */
PFD_SUPPORT_OPENGL |
PFD_DRAW_TO_WINDOW |
PFD_DOUBLEBUFFER, /* support double-buffering */
PFD_TYPE_RGBA, /* color type */
16, /* prefered color depth */
0, 0, 0, 0, 0, 0, /* color bits (ignored) */
0, /* no alpha buffer */
0, /* alpha bits (ignored) */
0, /* no accumulation buffer */
0, 0, 0, 0, /* accum bits (ignored) */
16, /* depth buffer */
0, /* no stencil buffer */
0, /* no auxiliary buffers */
PFD_MAIN_PLANE, /* main layer */
0, /* reserved */
0, 0, 0, /* no layer, visible, damage masks */
};
int pixelFormat;
pixelFormat = ChoosePixelFormat(hDC, &pfd);
if (pixelFormat == 0) {
MessageBox(WindowFromDC(hDC), "ChoosePixelFormat failed.", "Error",
MB_ICONERROR | MB_OK);
exit(1);
}
if (SetPixelFormat(hDC, pixelFormat, &pfd) != TRUE) {
MessageBox(WindowFromDC(hDC), "SetPixelFormat failed.", "Error",
MB_ICONERROR | MB_OK);
exit(1);
}
}
void
setupPalette(HDC hDC)
{
int pixelFormat = GetPixelFormat(hDC);
PIXELFORMATDESCRIPTOR pfd;
LOGPALETTE* pPal;
int paletteSize;
DescribePixelFormat(hDC, pixelFormat, sizeof(PIXELFORMATDESCRIPTOR), &pfd);
if (pfd.dwFlags & PFD_NEED_PALETTE) {
paletteSize = 1 << pfd.cColorBits;
} else {
return;
}
pPal = (LOGPALETTE*)
malloc(sizeof(LOGPALETTE) + paletteSize * sizeof(PALETTEENTRY));
pPal->palVersion = 0x300;
pPal->palNumEntries = paletteSize;
/* build a simple RGB color palette */
{
int redMask = (1 << pfd.cRedBits) - 1;
int greenMask = (1 << pfd.cGreenBits) - 1;
int blueMask = (1 << pfd.cBlueBits) - 1;
int i;
for (i=0; i<paletteSize; ++i) {
pPal->palPalEntry[i].peRed =
(((i >> pfd.cRedShift) & redMask) * 255) / redMask;
pPal->palPalEntry[i].peGreen =
(((i >> pfd.cGreenShift) & greenMask) * 255) / greenMask;
pPal->palPalEntry[i].peBlue =
(((i >> pfd.cBlueShift) & blueMask) * 255) / blueMask;
pPal->palPalEntry[i].peFlags = 0;
}
}
hPalette = CreatePalette(pPal);
free(pPal);
if (hPalette) {
SelectPalette(hDC, hPalette, FALSE);
RealizePalette(hDC);
}
}
LRESULT APIENTRY
WndProc(
HWND hWnd,
UINT message,
WPARAM wParam,
LPARAM lParam)
{
switch (message) {
case WM_CREATE:
/* initialize OpenGL rendering */
hDC = GetDC(hWnd);
setupPixelFormat(hDC);
setupPalette(hDC);
hGLRC = wglCreateContext(hDC);
wglMakeCurrent(hDC, hGLRC);
init();
return 0;
case WM_DESTROY:
/* finish OpenGL rendering */
if (hGLRC) {
wglMakeCurrent(NULL, NULL);
wglDeleteContext(hGLRC);
}
if (hPalette) {
DeleteObject(hPalette);
}
ReleaseDC(hWnd, hDC);
PostQuitMessage(0);
return 0;
case WM_SIZE:
/* track window size changes */
if (hGLRC) {
winWidth = (int) LOWORD(lParam);
winHeight = (int) HIWORD(lParam);
resize();
return 0;
}
case WM_PALETTECHANGED:
/* realize palette if this is *not* the current window */
if (hGLRC && hPalette && (HWND) wParam != hWnd) {
UnrealizeObject(hPalette);
SelectPalette(hDC, hPalette, FALSE);
RealizePalette(hDC);
redraw();
break;
}
break;
case WM_QUERYNEWPALETTE:
/* realize palette if this is the current window */
if (hGLRC && hPalette) {
UnrealizeObject(hPalette);
SelectPalette(hDC, hPalette, FALSE);
RealizePalette(hDC);
redraw();
return TRUE;
}
break;
case WM_PAINT:
{
PAINTSTRUCT ps;
BeginPaint(hWnd, &ps);
if (hGLRC) {
redraw();
}
EndPaint(hWnd, &ps);
return 0;
}
break;
case WM_CHAR:
/* handle keyboard input */
switch ((int)wParam) {
case VK_ESCAPE:
DestroyWindow(hWnd);
return 0;
default:
break;
}
break;
default:
break;
}
return DefWindowProc(hWnd, message, wParam, lParam);
}
int APIENTRY
WinMain(
HINSTANCE hCurrentInst,
HINSTANCE hPreviousInst,
LPSTR lpszCmdLine,
int nCmdShow)
{
WNDCLASS wndClass;
HWND hWnd;
MSG msg;
/* register window class */
wndClass.style = CS_HREDRAW | CS_VREDRAW;
wndClass.lpfnWndProc = WndProc;
wndClass.cbClsExtra = 0;
wndClass.cbWndExtra = 0;
wndClass.hInstance = hCurrentInst;
wndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
wndClass.hbrBackground = GetStockObject(BLACK_BRUSH);
wndClass.lpszMenuName = NULL;
wndClass.lpszClassName = className;
RegisterClass(&wndClass);
/* create window */
hWnd = CreateWindow(
className, windowName,
WS_OVERLAPPEDWINDOW | WS_CLIPCHILDREN | WS_CLIPSIBLINGS,
winX, winY, winWidth, winHeight,
NULL, NULL, hCurrentInst, NULL);
/* display window */
ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);
/* process messages */
while (GetMessage(&msg, NULL, 0, 0) == TRUE) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return msg.wParam;
}
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