| |
| |
| /* |
| * A demonstration of using the GLXPixmap functions. This program is in |
| * the public domain. |
| * |
| * Brian Paul |
| */ |
| |
| |
| #include <GL/gl.h> |
| #define GLX_GLXEXT_PROTOTYPES |
| #include <GL/glx.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| |
| static GLXContext ctx; |
| static XVisualInfo *visinfo; |
| static GC gc; |
| |
| |
| |
| static Window make_rgb_window( Display *dpy, |
| unsigned int width, unsigned int height ) |
| { |
| const int sbAttrib[] = { GLX_RGBA, |
| GLX_RED_SIZE, 1, |
| GLX_GREEN_SIZE, 1, |
| GLX_BLUE_SIZE, 1, |
| None }; |
| const int dbAttrib[] = { GLX_RGBA, |
| GLX_RED_SIZE, 1, |
| GLX_GREEN_SIZE, 1, |
| GLX_BLUE_SIZE, 1, |
| GLX_DOUBLEBUFFER, |
| None }; |
| int scrnum; |
| XSetWindowAttributes attr; |
| unsigned long mask; |
| Window root; |
| Window win; |
| |
| scrnum = DefaultScreen( dpy ); |
| root = RootWindow( dpy, scrnum ); |
| |
| visinfo = glXChooseVisual( dpy, scrnum, (int *) sbAttrib ); |
| if (!visinfo) { |
| visinfo = glXChooseVisual( dpy, scrnum, (int *) dbAttrib ); |
| if (!visinfo) { |
| printf("Error: couldn't get an RGB visual\n"); |
| exit(1); |
| } |
| } |
| |
| /* window attributes */ |
| attr.background_pixel = 0; |
| attr.border_pixel = 0; |
| /* TODO: share root colormap if possible */ |
| attr.colormap = XCreateColormap( dpy, root, visinfo->visual, AllocNone); |
| attr.event_mask = StructureNotifyMask | ExposureMask; |
| mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask; |
| |
| win = XCreateWindow( dpy, root, 0, 0, width, height, |
| 0, visinfo->depth, InputOutput, |
| visinfo->visual, mask, &attr ); |
| |
| /* make an X GC so we can do XCopyArea later */ |
| gc = XCreateGC( dpy, win, 0, NULL ); |
| |
| /* need indirect context */ |
| ctx = glXCreateContext( dpy, visinfo, NULL, False ); |
| if (!ctx) { |
| printf("Error: glXCreateContext failed\n"); |
| exit(-1); |
| } |
| |
| printf("Direct rendering: %s\n", glXIsDirect(dpy, ctx) ? "Yes" : "No"); |
| |
| return win; |
| } |
| |
| |
| static GLXPixmap make_pixmap( Display *dpy, Window win, |
| unsigned int width, unsigned int height, |
| Pixmap *pixmap) |
| { |
| Pixmap pm; |
| GLXPixmap glxpm; |
| XWindowAttributes attr; |
| |
| pm = XCreatePixmap( dpy, win, width, height, visinfo->depth ); |
| if (!pm) { |
| printf("Error: XCreatePixmap failed\n"); |
| exit(-1); |
| } |
| |
| XGetWindowAttributes( dpy, win, &attr ); |
| |
| /* |
| * IMPORTANT: |
| * Use the glXCreateGLXPixmapMESA funtion when using Mesa because |
| * Mesa needs to know the colormap associated with a pixmap in order |
| * to render correctly. This is because Mesa allows RGB rendering |
| * into any kind of visual, not just TrueColor or DirectColor. |
| */ |
| #ifdef GLX_MESA_pixmap_colormap |
| if (strstr(glXQueryExtensionsString(dpy, 0), "GLX_MESA_pixmap_colormap")) { |
| /* stand-alone Mesa, specify the colormap */ |
| glxpm = glXCreateGLXPixmapMESA( dpy, visinfo, pm, attr.colormap ); |
| } |
| else { |
| glxpm = glXCreateGLXPixmap( dpy, visinfo, pm ); |
| } |
| #else |
| /* This will work with Mesa too if the visual is TrueColor or DirectColor */ |
| glxpm = glXCreateGLXPixmap( dpy, visinfo, pm ); |
| #endif |
| |
| if (!glxpm) { |
| printf("Error: GLXCreateGLXPixmap failed\n"); |
| exit(-1); |
| } |
| |
| *pixmap = pm; |
| |
| return glxpm; |
| } |
| |
| |
| |
| static void event_loop( Display *dpy, GLXPixmap pm ) |
| { |
| XEvent event; |
| |
| while (1) { |
| XNextEvent( dpy, &event ); |
| |
| switch (event.type) { |
| case Expose: |
| printf("Redraw\n"); |
| /* copy the image from GLXPixmap to window */ |
| XCopyArea( dpy, pm, event.xany.window, /* src, dest */ |
| gc, 0, 0, 300, 300, /* gc, src pos, size */ |
| 0, 0 ); /* dest pos */ |
| break; |
| case ConfigureNotify: |
| /* nothing */ |
| break; |
| } |
| } |
| } |
| |
| |
| |
| int main( int argc, char *argv[] ) |
| { |
| Display *dpy; |
| Window win; |
| Pixmap pm; |
| GLXPixmap glxpm; |
| |
| dpy = XOpenDisplay(NULL); |
| |
| win = make_rgb_window( dpy, 300, 300 ); |
| glxpm = make_pixmap( dpy, win, 300, 300, &pm ); |
| |
| glXMakeCurrent( dpy, glxpm, ctx ); |
| printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER)); |
| |
| /* Render an image into the pixmap */ |
| glShadeModel( GL_FLAT ); |
| glClearColor( 0.5, 0.5, 0.5, 1.0 ); |
| glClear( GL_COLOR_BUFFER_BIT ); |
| glViewport( 0, 0, 300, 300 ); |
| glOrtho( -1.0, 1.0, -1.0, 1.0, -1.0, 1.0 ); |
| glColor3f( 0.0, 1.0, 1.0 ); |
| glRectf( -0.75, -0.75, 0.75, 0.75 ); |
| glFlush(); |
| glXWaitGL(); |
| |
| XMapWindow( dpy, win ); |
| |
| event_loop( dpy, pm ); |
| return 0; |
| } |