window-test.c

#include <assert.h>
#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/keysym.h>
#include <GLES2/gl2.h>  /* use OpenGL ES 2.x */
#include <EGL/egl.h>

void run_tests(void);

static void reshape(int width, int height)
{
   glViewport(0, 0, (GLint) width, (GLint) height);
}

static void
make_x_window(Display *x_dpy, EGLDisplay egl_dpy,
              const char *name,
              int x, int y, int width, int height,
              Window *winRet,
              EGLContext *ctxRet,
              EGLSurface *surfRet)
{
   static const EGLint attribs[] = {
      EGL_RED_SIZE, 1,
      EGL_GREEN_SIZE, 1,
      EGL_BLUE_SIZE, 1,
/*      EGL_DEPTH_SIZE, 1, */
      EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
      EGL_NONE
   };
   static const EGLint ctx_attribs[] = {
      EGL_CONTEXT_CLIENT_VERSION, 2,
      EGL_NONE
   };

   int scrnum;
   XSetWindowAttributes attr;
   unsigned long mask;
   Window root;
   Window win;
   XVisualInfo *visInfo, visTemplate;
   int num_visuals;
   EGLContext ctx;
   EGLConfig config;
   EGLint num_configs;
   EGLint vid;

   scrnum = DefaultScreen( x_dpy );
   root = RootWindow( x_dpy, scrnum );

   if (!eglChooseConfig( egl_dpy, attribs, &config, 1, &num_configs)) {
      printf("Error: couldn't get an EGL visual config\n");
      exit(1);
   }

   assert(config);
   assert(num_configs > 0);

   if (!eglGetConfigAttrib(egl_dpy, config, EGL_NATIVE_VISUAL_ID, &vid)) {
      printf("Error: eglGetConfigAttrib() failed\n");
      exit(1);
   }

   /* The X window visual must match the EGL config */
   visTemplate.visualid = vid;
   visInfo = XGetVisualInfo(x_dpy, VisualIDMask, &visTemplate, &num_visuals);
   if (!visInfo) {
      printf("Error: couldn't get X visual\n");
      exit(1);
   }

   /* window attributes */
   attr.background_pixel = 0;
   attr.border_pixel = 0;
   attr.colormap = XCreateColormap( x_dpy, root, visInfo->visual, AllocNone);
   attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
   mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;

   win = XCreateWindow( x_dpy, root, 0, 0, width, height,
		        0, visInfo->depth, InputOutput,
		        visInfo->visual, mask, &attr );

   /* set hints and properties */
   {
      XSizeHints sizehints;
      sizehints.x = x;
      sizehints.y = y;
      sizehints.width  = width;
      sizehints.height = height;
      sizehints.flags = USSize | USPosition;
      XSetNormalHints(x_dpy, win, &sizehints);
      XSetStandardProperties(x_dpy, win, name, name,
                              None, (char **)NULL, 0, &sizehints);
   }

   eglBindAPI(EGL_OPENGL_ES_API);

   ctx = eglCreateContext(egl_dpy, config, EGL_NO_CONTEXT, ctx_attribs );
   if (!ctx) {
      printf("Error: eglCreateContext failed\n");
      exit(1);
   }

   /* test eglQueryContext() */
   {
      EGLint val;
      eglQueryContext(egl_dpy, ctx, EGL_CONTEXT_CLIENT_VERSION, &val);
      assert(val == 2);
   }

   *surfRet = eglCreateWindowSurface(egl_dpy, config, win, NULL);
   if (!*surfRet) {
      printf("Error: eglCreateWindowSurface failed\n");
      exit(1);
   }

   /* sanity checks */
   {
      EGLint val;
      eglQuerySurface(egl_dpy, *surfRet, EGL_WIDTH, &val);
      assert(val == width);
      eglQuerySurface(egl_dpy, *surfRet, EGL_HEIGHT, &val);
      assert(val == height);
      assert(eglGetConfigAttrib(egl_dpy, config, EGL_SURFACE_TYPE, &val));
      assert(val & EGL_WINDOW_BIT);
   }

   XFree(visInfo);

   *winRet = win;
   *ctxRet = ctx;
}

static void
usage(void)
{
   printf("Usage:\n");
   printf("  -display <displayname>  set the display to run on\n");
   printf("  -info                   display OpenGL renderer info\n");
}

EGLDisplay egl_dpy;
EGLSurface egl_surf;

void present(void)
{
   eglSwapBuffers(egl_dpy, egl_surf);
}

int
main(int argc, char *argv[])
{
   const int winWidth = 32, winHeight = 32;
   Display *x_dpy;
   Window win;
   EGLContext egl_ctx;
   char *dpyName = NULL;
   EGLint egl_major, egl_minor;
   int i;
   const char *s;

   x_dpy = XOpenDisplay(dpyName);
   if (!x_dpy) {
      printf("Error: couldn't open display %s\n",
	     dpyName ? dpyName : getenv("DISPLAY"));
      return -1;
   }

   egl_dpy = eglGetDisplay(x_dpy);
   if (!egl_dpy) {
      printf("Error: eglGetDisplay() failed\n");
      return -1;
   }

   if (!eglInitialize(egl_dpy, &egl_major, &egl_minor)) {
      printf("Error: eglInitialize() failed\n");
      return -1;
   }

   s = eglQueryString(egl_dpy, EGL_VERSION);
   printf("EGL_VERSION = %s\n", s);

   s = eglQueryString(egl_dpy, EGL_VENDOR);
   printf("EGL_VENDOR = %s\n", s);

   s = eglQueryString(egl_dpy, EGL_EXTENSIONS);
   printf("EGL_EXTENSIONS = %s\n", s);

   s = eglQueryString(egl_dpy, EGL_CLIENT_APIS);
   printf("EGL_CLIENT_APIS = %s\n", s);

   make_x_window(x_dpy, egl_dpy,
                 "OpenGL ES 2.x tri", 0, 0, winWidth, winHeight,
                 &win, &egl_ctx, &egl_surf);

   XMapWindow(x_dpy, win);
   if (!eglMakeCurrent(egl_dpy, egl_surf, egl_surf, egl_ctx)) {
      printf("Error: eglMakeCurrent() failed\n");
      return -1;
   }

   run_tests();

   eglDestroyContext(egl_dpy, egl_ctx);
   eglDestroySurface(egl_dpy, egl_surf);
   eglTerminate(egl_dpy);


   XDestroyWindow(x_dpy, win);
   XCloseDisplay(x_dpy);

   return 0;
}