76个qt+例子.+非常适合学习qt编程%2C-76+qt+example.+Qt+very+suitable+for+lear...

/* Copyright (c) Mark J. Kilgard, 1996. */ /* This program is freely distributable without licensing fees and is provided without guarantee or warrantee expressed or implied. This program is -not- in the public domain. */ #include <stdlib.h> #include <stdio.h> #include <X11/Xlib.h> #include <GL/glx.h> static char *ClassOf(int c); static char *Format(int n, int w); void main(int argc, char *argv[]) { Display *dpy; XVisualInfo match, *visualList, *vi, *visualToTry; int errorBase, eventBase, major, minor, found; int glxCapable, bufferSize, level, renderType, doubleBuffer, stereo, auxBuffers, redSize, greenSize, blueSize, alphaSize, depthSize, stencilSize, acRedSize, acGreenSize, acBlueSize, acAlphaSize; dpy = XOpenDisplay(NULL); if (!dpy) { fprintf(stderr, "Could not connect to %s.\n", XDisplayName(NULL)); exit(1); } if (glXQueryExtension(dpy, &errorBase, &eventBase) == False) { fprintf(stderr, "OpenGL not supported by X server.\n"); exit(1); } glXQueryVersion(dpy, &major, &minor); printf("display: %s\n", XDisplayName(NULL)); printf("using GLX version: %d.%d\n\n", major, minor); match.screen = DefaultScreen(dpy); visualList = XGetVisualInfo(dpy, VisualScreenMask, &match, &found); printf(" visual bf lv rg d st r g b a ax dp st accum buffs\n"); printf(" id dep cl sz l ci b ro sz sz sz sz bf th cl r g b a\n"); printf("-------------------------------------------------------------\n"); visualToTry = NULL; for(vi = visualList; found > 0; found--, vi++) { glXGetConfig(dpy, vi, GLX_USE_GL, &glxCapable); if (glxCapable) { printf("0x%x %2d %s", vi->visualid, vi->depth, ClassOf(vi->class)); glXGetConfig(dpy, vi, GLX_BUFFER_SIZE, &bufferSize); glXGetConfig(dpy, vi, GLX_LEVEL, &level); glXGetConfig(dpy, vi, GLX_RGBA, &renderType); glXGetConfig(dpy, vi, GLX_DOUBLEBUFFER, &doubleBuffer); glXGetConfig(dpy, vi, GLX_STEREO, &stereo); glXGetConfig(dpy, vi, GLX_AUX_BUFFERS, &auxBuffers); glXGetConfig(dpy, vi, GLX_RED_SIZE, &redSize); glXGetConfig(dpy, vi, GLX_GREEN_SIZE, &greenSize); glXGetConfig(dpy, vi, GLX_BLUE_SIZE, &blueSize); glXGetConfig(dpy, vi, GLX_ALPHA_SIZE, &alphaSize); glXGetConfig(dpy, vi, GLX_DEPTH_SIZE, &depthSize); glXGetConfig(dpy, vi, GLX_STENCIL_SIZE, &stencilSize); glXGetConfig(dpy, vi, GLX_ACCUM_RED_SIZE, &acRedSize); glXGetConfig(dpy, vi, GLX_ACCUM_GREEN_SIZE, &acGreenSize); glXGetConfig(dpy, vi, GLX_ACCUM_BLUE_SIZE, &acBlueSize); glXGetConfig(dpy, vi, GLX_ACCUM_ALPHA_SIZE, &acAlphaSize); printf(" %2s %2s %1s %1s %1s ", Format(bufferSize, 2), Format(level, 2), renderType ? "r" : "c", doubleBuffer ? "y" : ".", stereo ? "y" : "."); printf("%2s %2s %2s %2s ", Format(redSize, 2), Format(greenSize, 2), Format(blueSize, 2), Format(alphaSize, 2)); printf("%2s %2s %2s %2s %2s %2s %2s", Format(auxBuffers, 2), Format(depthSize, 2), Format(stencilSize, 2), Format(acRedSize, 2), Format(acGreenSize, 2), Format(acBlueSize, 2), Format(acAlphaSize, 2)); printf("\n"); visualToTry = vi; } } if (visualToTry) { GLXContext context; Window window; Colormap colormap; XSetWindowAttributes swa; context = glXCreateContext(dpy, visualToTry, 0, GL_TRUE); colormap = XCreateColormap(dpy, RootWindow(dpy, visualToTry->screen), visualToTry->visual, AllocNone); swa.colormap = colormap; swa.border_pixel = 0; window = XCreateWindow(dpy, RootWindow(dpy, visualToTry->screen), 0, 0, 100, 100, 0, visualToTry->depth, InputOutput, visualToTry->visual, CWBorderPixel | CWColormap, &swa); glXMakeCurrent(dpy, window, context); printf("\n"); printf("OpenGL vendor string: %s\n", glGetString(GL_VENDOR)); printf("OpenGL renderer string: %s\n", glGetString(GL_RENDERER)); printf("OpenGL version string: %s\n", glGetString(GL_VERSION)); if (glXIsDirect(dpy, context)) printf("direct rendering: supported\n"); printf( "GL extensions: '%s'\n\n", glGetString(GL_EXTENSIONS) ); #if defined(GLX_VERSION_1_1) printf( "GLX extensions: '%s'\n\n", glXQueryExtensionsString( dpy, visualToTry->screen ) ); #endif } else printf("No GLX-capable visuals!\n"); XFree(visualList); } static char * ClassOf(int c) { switch (c) { case StaticGray: return "sg"; case GrayScale: return "gs"; case StaticColor: return "sc"; case PseudoColor: return "pc"; case TrueColor: return "tc"; case DirectColor: return "dc"; default: return "??"; } } static char * Format(int n, int w) { static char buffer[256]; static int bufptr; char *buf; if (bufptr >= sizeof(buffer) - w) bufptr = 0; buf = buffer + bufptr; if (n == 0) sprintf(buf, "%*s", w, "."); else sprintf(buf, "%*d", w, n); bufptr += w + 1; return buf; }