progs/egl: Add eglut.

eglut is a simple library with GLUT-like API.  It is intended to be used
by simple EGL demos.

1 files changed, 154 insertions, 0 deletions

diff --git a/progs/egl/eglut/eglut_screen.c b/progs/egl/eglut/eglut_screen.c
new file mode 100644
index 00000000000..50549e4bcf8
--- /dev/null
+++ b/progs/egl/eglut/eglut_screen.c
@@ -0,0 +1,154 @@
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+
+#define EGL_EGLEXT_PROTOTYPES
+#include "EGL/egl.h"
+#include "EGL/eglext.h"
+
+#include "eglutint.h"
+
+#define MAX_MODES 100
+
+static EGLScreenMESA kms_screen;
+static EGLModeMESA kms_mode;
+static EGLint kms_width, kms_height;
+
+void
+_eglutNativeInitDisplay(void)
+{
+   _eglut->native_dpy = EGL_DEFAULT_DISPLAY;
+   _eglut->surface_type = EGL_SCREEN_BIT_MESA;
+}
+
+void
+_eglutNativeFiniDisplay(void)
+{
+   kms_screen = 0;
+   kms_mode = 0;
+   kms_width = 0;
+   kms_height = 0;
+}
+
+static void
+init_kms(void)
+{
+   EGLModeMESA modes[MAX_MODES];
+   EGLint num_screens, num_modes;
+   EGLint width, height, best_mode;
+   EGLint i;
+
+   if (!eglGetScreensMESA(_eglut->dpy, &kms_screen, 1, &num_screens) ||
+         !num_screens)
+      _eglutFatal("eglGetScreensMESA failed\n");
+
+   if (!eglGetModesMESA(_eglut->dpy, kms_screen,
+            modes, MAX_MODES, &num_modes) || !num_modes)
+      _eglutFatal("eglGetModesMESA failed!\n");
+
+   printf("Found %d modes:\n", num_modes);
+
+   best_mode = 0;
+   width = 0;
+   height = 0;
+   for (i = 0; i < num_modes; i++) {
+      EGLint w, h;
+      eglGetModeAttribMESA(_eglut->dpy, modes[i], EGL_WIDTH, &w);
+      eglGetModeAttribMESA(_eglut->dpy, modes[i], EGL_HEIGHT, &h);
+      printf("%3d: %d x %d\n", i, w, h);
+      if (w > width && h > height) {
+         width = w;
+         height = h;
+         best_mode = i;
+      }
+   }
+
+   printf("Will use screen size: %d x %d\n", width, height);
+
+   kms_mode = modes[best_mode];
+   kms_width = width;
+   kms_height = height;
+}
+
+void
+_eglutNativeInitWindow(struct eglut_window *win, const char *title,
+                       int x, int y, int w, int h)
+{
+   EGLint surf_attribs[16];
+   EGLint i;
+   const char *exts;
+
+   exts = eglQueryString(_eglut->dpy, EGL_EXTENSIONS);
+   if (!exts || !strstr(exts, "EGL_MESA_screen_surface"))
+      _eglutFatal("EGL_MESA_screen_surface is not supported\n");
+
+   init_kms();
+
+   i = 0;
+   surf_attribs[i++] = EGL_WIDTH;
+   surf_attribs[i++] = kms_width;
+   surf_attribs[i++] = EGL_HEIGHT;
+   surf_attribs[i++] = kms_height;
+   surf_attribs[i++] = EGL_NONE;
+
+   /* create surface */
+   win->native.u.surface = eglCreateScreenSurfaceMESA(_eglut->dpy,
+         win->config, surf_attribs);
+   if (win->native.u.surface == EGL_NO_SURFACE)
+      _eglutFatal("eglCreateScreenSurfaceMESA failed\n");
+
+   if (!eglShowScreenSurfaceMESA(_eglut->dpy, kms_screen,
+            win->native.u.surface, kms_mode))
+      _eglutFatal("eglShowScreenSurfaceMESA failed\n");
+
+   win->native.width = kms_width;
+   win->native.height = kms_height;
+}
+
+void
+_eglutNativeFiniWindow(struct eglut_window *win)
+{
+   eglShowScreenSurfaceMESA(_eglut->dpy,
+         kms_screen, EGL_NO_SURFACE, 0);
+   eglDestroySurface(_eglut->dpy, win->native.u.surface);
+}
+
+void
+_eglutNativeEventLoop(void)
+{
+   int start = _eglutNow();
+   int frames = 0;
+
+   _eglut->redisplay = 1;
+
+   while (1) {
+      struct eglut_window *win = _eglut->current;
+      int now = _eglutNow();
+
+      if (now - start > 5000) {
+         double elapsed = (double) (now - start) / 1000.0;
+
+         printf("%d frames in %3.1f seconds = %6.3f FPS\n",
+               frames, elapsed, frames / elapsed);
+
+         start = now;
+         frames = 0;
+
+         /* send escape */
+         if (win->keyboard_cb)
+            win->keyboard_cb(27);
+      }
+
+      if (_eglut->idle_cb)
+         _eglut->idle_cb();
+
+      if (_eglut->redisplay) {
+         _eglut->redisplay = 0;
+
+         if (win->display_cb)
+            win->display_cb();
+         eglSwapBuffers(_eglut->dpy, win->surface);
+         frames++;
+      }
+   }
+}