1 files changed, 131 insertions, 0 deletions
diff --git a/src/surface-egl.cpp b/src/surface-egl.cpp
new file mode 100644
index 0000000..4676546
--- /dev/null
+++ b/src/surface-egl.cpp
@@ -0,0 +1,131 @@
+#include <err.h>
+#include <stdlib.h>
+#include <cairo.h>
+#include <cairo-gl.h>
+
+#include <EGL/egl.h>
+#include <GLES3/gl3.h>
+
+struct graphics_state {
+  Display   *dpy;
+  Window     window;
+
+  EGLDisplay egl_display;
+  EGLContext egl_context;
+  EGLSurface egl_surface;
+};
+
+static void
+cleanup (void *data)
+{
+  struct graphics_state *state = (graphics_state*)data;
+
+  eglDestroyContext (state->egl_display, state->egl_context);
+  eglDestroySurface (state->egl_display, state->egl_surface);
+  eglTerminate (state->egl_display);
+
+  XCloseDisplay (state->dpy);
+
+  free (state);
+}
+
+cairo_surface_t *
+create_source_surface_egl (int width, int height)
+{
+  struct graphics_state *state;
+  cairo_device_t *cairo_device;
+  cairo_surface_t *cairo_surface;
+
+  EGLint attr[] = {
+    EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
+    EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
+    EGL_RED_SIZE, 1,
+    EGL_GREEN_SIZE, 1,
+    EGL_BLUE_SIZE, 1,
+    EGL_ALPHA_SIZE, 1,
+    EGL_STENCIL_SIZE, 1,
+    EGL_SAMPLES, 4,
+    EGL_SAMPLE_BUFFERS, 1,
+    EGL_NONE
+  };
+  EGLint ctx_attr[] = {
+    EGL_CONTEXT_CLIENT_VERSION, 3,
+    EGL_NONE
+  };
+  EGLConfig config;
+  EGLint num;
+  EGLint major, minor;
+
+  state = (graphics_state*) malloc (sizeof (struct graphics_state));
+  if (!state) {
+    warnx ("Out of memory\n");
+    return NULL;
+  }
+
+  state->dpy = XOpenDisplay (NULL);
+  if (state->dpy == NULL) {
+    warnx ("Failed to open display: %s\n", XDisplayName (0));
+    return NULL;
+  }
+
+  state->window = XCreateSimpleWindow (state->dpy, DefaultRootWindow (state->dpy),
+				       0, 0,
+				       width, height,
+				       0,
+				       BlackPixel (state->dpy, DefaultRootWindow (state->dpy)),
+				       BlackPixel (state->dpy, DefaultRootWindow (state->dpy)));
+  XMapWindow (state->dpy, state->window);
+
+  state->egl_display = eglGetDisplay ((EGLNativeDisplayType) state->dpy);
+  if (state->egl_display == EGL_NO_DISPLAY) {
+    warnx ("Cannot get egl display\n");
+    return NULL;
+  }
+
+  if (! eglInitialize (state->egl_display, &major, &minor)) {
+    warnx ("Cannot initialize egl\n");
+    return NULL;
+  }
+
+  if (! eglBindAPI (EGL_OPENGL_ES_API)) {
+    warnx ("Cannot bind egl to gles2 API\n");
+    return NULL;
+  }
+
+  if (! eglChooseConfig (state->egl_display, attr, &config, 1, &num)) {
+    warnx ("Cannot get egl configuration\n");
+    return NULL;
+  }
+
+  state->egl_context = eglCreateContext (state->egl_display, config, NULL, ctx_attr);
+  if (state->egl_context == EGL_NO_CONTEXT) {
+    warnx ("Cannot create egl context\n");
+    return NULL;
+  }
+
+  state->egl_surface = eglCreateWindowSurface (state->egl_display, config, state->window, NULL);
+  if (state->egl_surface == EGL_NO_SURFACE) {
+    warnx ("Cannot create egl window surface\n");
+    return NULL;
+  }
+
+  cairo_device = cairo_egl_device_create (state->egl_display, state->egl_context);
+  cairo_gl_device_set_thread_aware (cairo_device, 0);
+  cairo_surface = cairo_gl_surface_create_for_egl (cairo_device,
+						   state->egl_surface,
+						   width, height);
+
+  if (cairo_device_set_user_data (cairo_device,
+                                  (cairo_user_data_key_t *) cleanup,
+                                  state,
+                                  cleanup))
+    {
+      warnx ("Failed to setup cleanup callback closure\n");
+      cleanup (state);
+      return NULL;
+    }
+
+  cairo_device_destroy (cairo_device);
+
+  return cairo_surface;
+}