compositor: Use GL_EXT_unpack_subimage for texture updates

diff --git a/src/compositor.c b/src/compositor.c
index 8145a3e..47305cc 100644 (file)
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -714,6 +714,9 @@ weston_surface_attach(struct wl_surface *surface, struct wl_buffer *buffer)
 
        if (wl_buffer_is_shm(buffer)) {
                es->pitch = wl_shm_buffer_get_stride(buffer) / 4;
+               glTexImage2D(GL_TEXTURE_2D, 0, GL_BGRA_EXT,
+                            es->pitch, es->buffer->height, 0,
+                            GL_BGRA_EXT, GL_UNSIGNED_BYTE, NULL);
        } else {
                if (es->image != EGL_NO_IMAGE_KHR)
                        ec->destroy_image(ec->display, es->image);
@@ -1177,13 +1180,13 @@ surface_damage(struct wl_client *client,
 
        if (es->buffer && wl_buffer_is_shm(es->buffer)) {
                glBindTexture(GL_TEXTURE_2D, es->texture);
-               glTexImage2D(GL_TEXTURE_2D, 0, GL_BGRA_EXT,
-                            es->pitch, es->buffer->height, 0,
-                            GL_BGRA_EXT, GL_UNSIGNED_BYTE,
-                            wl_shm_buffer_get_data(es->buffer));
+               glPixelStorei(GL_UNPACK_ROW_LENGTH, es->pitch);
+               glPixelStorei(GL_UNPACK_SKIP_PIXELS, x);
+               glPixelStorei(GL_UNPACK_SKIP_ROWS, y);
 
-               /* Hmm, should use glTexSubImage2D() here but GLES2 doesn't
-                * support any unpack attributes except GL_UNPACK_ALIGNMENT. */
+               glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height,
+                               GL_BGRA_EXT, GL_UNSIGNED_BYTE,
+                               wl_shm_buffer_get_data(es->buffer));
        }
 }
 
@@ -2357,6 +2360,11 @@ weston_compositor_init(struct weston_compositor *ec, struct wl_display *display)
                return -1;
        }
 
+       if (!strstr(extensions, "GL_EXT_unpack_subimage")) {
+               fprintf(stderr, "GL_EXT_unpack_subimage not available\n");
+               return -1;
+       }
+
        extensions =
                (const char *) eglQueryString(ec->display, EGL_EXTENSIONS);
        if (strstr(extensions, "EGL_WL_bind_wayland_display"))