Start wrapping OpenGL, and print periodic FPS value to stdout.

[fips] / glxwrap.c

diff --git a/glxwrap.c b/glxwrap.c
new file mode 100644 (file)
index 0000000..51b5faf
--- /dev/null
+++ b/glxwrap.c
@@ -0,0 +1,96 @@
+/* Copyright © 2013, Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <dlfcn.h>
+
+#include <X11/Xlib.h>
+#include <GL/gl.h>
+#include <GL/glx.h>
+#include <GL/glext.h>
+
+#include <sys/time.h>
+
+typedef void (* fips_glXSwapBuffers_t)(Display *dpy, GLXDrawable drawable);
+
+static void *
+lookup (const char *name)
+{
+       const char *libgl_filename = "libGL.so.1";
+       static void *libgl_handle = NULL;
+
+       if (! libgl_handle) {
+               libgl_handle = dlopen (libgl_filename, RTLD_NOW);
+               if (! libgl_handle) {
+                       fprintf (stderr, "Error: Failed to dlopen %s\n",
+                                libgl_filename);
+                       exit (1);
+               }
+       }
+
+       return dlsym (libgl_handle, name);
+}
+
+static void
+call_glXSwapBuffers (Display *dpy, GLXDrawable drawable)
+{
+       static fips_glXSwapBuffers_t real_glXSwapBuffers = NULL;
+       const char *name = "glXSwapBuffers";
+
+       if (! real_glXSwapBuffers) {
+               real_glXSwapBuffers = (fips_glXSwapBuffers_t) lookup (name);
+               if (! real_glXSwapBuffers) {
+                       fprintf (stderr, "Error: Failed to find function %s.\n",
+                                name);
+                       return;
+               }
+       }
+       real_glXSwapBuffers (dpy, drawable);
+}      
+
+void
+glXSwapBuffers (Display *dpy, GLXDrawable drawable)
+{
+       static int initialized = 0;
+       static int frames;
+       static struct timeval tv_start, tv_now;
+
+       if (! initialized) {
+               frames = 0;
+               gettimeofday (&tv_start, NULL);
+               initialized = 1;
+       }
+
+       call_glXSwapBuffers (dpy, drawable);
+
+       frames++;
+       if (frames % 60 == 0) {
+               double fps;
+               gettimeofday (&tv_now, NULL);
+
+               fps = (double) frames / (tv_now.tv_sec - tv_start.tv_sec +
+                                        (tv_now.tv_usec - tv_start.tv_usec) / 1.0e6);
+
+               printf("FPS: %.3f\n", fps);
+       }
+}