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#define USE_MINIGLX 1 /* 1 = use Mini GLX, 0 = use Xlib/GLX */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <GL/gl.h>
#if USE_MINIGLX
#include <GL/miniglx.h>
#else
#include <GL/glx.h>
#include <X11/Xlib.h>
#endif
static void _subset_Rectf( GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2 )
{
glBegin( GL_QUADS );
glVertex2f( x1, y1 );
glVertex2f( x2, y1 );
glVertex2f( x2, y2 );
glVertex2f( x1, y2 );
glEnd();
}
/*
* Create a simple double-buffered RGBA window.
*/
static Window
MakeWindow(Display * dpy, unsigned int width, unsigned int height)
{
int visAttributes[] = {
GLX_RGBA,
GLX_RED_SIZE, 1,
GLX_GREEN_SIZE, 1,
GLX_BLUE_SIZE, 1,
GLX_DOUBLEBUFFER,
None
};
XSetWindowAttributes attr;
unsigned long attrMask;
Window root;
Window win;
GLXContext ctx;
XVisualInfo *visinfo;
root = RootWindow(dpy, 0);
/* Choose GLX visual / pixel format */
visinfo = glXChooseVisual(dpy, 0, visAttributes);
if (!visinfo) {
printf("Error: couldn't get an RGB, Double-buffered visual\n");
exit(1);
}
/* Create the window */
attr.background_pixel = 0;
attr.border_pixel = 0;
attr.colormap = XCreateColormap(dpy, root, visinfo->visual, AllocNone);
attrMask = CWBackPixel | CWBorderPixel | CWColormap;
win = XCreateWindow(dpy, root, 0, 0, width, height,
0, visinfo->depth, InputOutput,
visinfo->visual, attrMask, &attr);
if (!win) {
printf("Error: XCreateWindow failed\n");
exit(1);
}
/* Display the window */
XMapWindow(dpy, win);
/* Create GLX rendering context */
ctx = glXCreateContext(dpy, visinfo, NULL, True);
if (!ctx) {
printf("Error: glXCreateContext failed\n");
exit(1);
}
/* Bind the rendering context and window */
glXMakeCurrent(dpy, win, ctx);
glViewport(0, 0, width, height);
return win;
}
/*
* Draw a few frames of a rotating square.
*/
static void
DrawFrames(Display * dpy, Window win)
{
int angle;
glShadeModel(GL_FLAT);
glClearColor(0.5, 0.5, 0.5, 1.0);
for (angle = 0; angle < 360; angle += 10) {
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0, 1.0, 0.0);
glPushMatrix();
glRotatef(angle, 0, 0, 1);
_subset_Rectf(-0.8, -0.8, 0.8, 0.8);
glPopMatrix();
glXSwapBuffers(dpy, win);
sleep(1);
}
}
int
main(int argc, char *argv[])
{
Display *dpy;
Window win;
dpy = XOpenDisplay(NULL);
if (!dpy) {
printf("Error: XOpenDisplay failed\n");
return 1;
}
win = MakeWindow(dpy, 300, 300);
DrawFrames(dpy, win);
return 0;
}
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