[mutter] wayland/buffer: Fall back to CoglTexture2DSliced

[Jonas Ådahl <jadahl src gnome org>]

commit ddd2ce3a88293633d309d99ed61ebf458ef3f42c
Author: Robert Mader <robert mader posteo de>
Date:   Sat Feb 16 13:35:22 2019 +0100

    wayland/buffer: Fall back to CoglTexture2DSliced
    
    XWayland creates buffers of the combined size of all connected displays.
    This can, especially on older but still in use hardware, exceed the limits
    of the GPU.
    
    If that is the case, use `CoglTexture2DSliced` instead of `CoglTexture2D`
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/447

 src/wayland/meta-wayland-buffer.c | 33 +++++++++++++++++++++++++--------
 1 file changed, 25 insertions(+), 8 deletions(-)
---
diff --git a/src/wayland/meta-wayland-buffer.c b/src/wayland/meta-wayland-buffer.c
index 8fda90016..ac2eb98b7 100644
--- a/src/wayland/meta-wayland-buffer.c
+++ b/src/wayland/meta-wayland-buffer.c
@@ -209,7 +209,7 @@ shm_buffer_attach (MetaWaylandBuffer  *buffer,
   CoglPixelFormat format;
   CoglTextureComponents components;
   CoglBitmap *bitmap;
-  CoglTexture2D *texture_2d;
+  CoglTexture *new_texture;
 
   shm_buffer = wl_shm_buffer_get (buffer->resource);
   stride = wl_shm_buffer_get_stride (shm_buffer);
@@ -238,20 +238,37 @@ shm_buffer_attach (MetaWaylandBuffer  *buffer,
                                      stride,
                                      wl_shm_buffer_get_data (shm_buffer));
 
-  texture_2d = cogl_texture_2d_new_from_bitmap (bitmap);
-  cogl_texture_set_components (COGL_TEXTURE (texture_2d), components);
+  new_texture = COGL_TEXTURE (cogl_texture_2d_new_from_bitmap (bitmap));
+  cogl_texture_set_components (new_texture, components);
 
-  cogl_object_unref (bitmap);
+  if (!cogl_texture_allocate (new_texture, error))
+    {
+      g_clear_pointer (&new_texture, cogl_object_unref);
+      if (g_error_matches (*error, COGL_TEXTURE_ERROR, COGL_TEXTURE_ERROR_SIZE))
+        {
+          CoglTexture2DSliced *texture_sliced;
+
+          g_clear_error (error);
 
-  if (!cogl_texture_allocate (COGL_TEXTURE (texture_2d), error))
-    g_clear_pointer (&texture_2d, cogl_object_unref);
+          texture_sliced =
+            cogl_texture_2d_sliced_new_from_bitmap (bitmap,
+                                                    COGL_TEXTURE_MAX_WASTE);
+          new_texture = COGL_TEXTURE (texture_sliced);
+          cogl_texture_set_components (new_texture, components);
+
+          if (!cogl_texture_allocate (new_texture, error))
+            g_clear_pointer (&new_texture, cogl_object_unref);
+        }
+    }
+
+  cogl_object_unref (bitmap);
 
   wl_shm_buffer_end_access (shm_buffer);
 
-  if (!texture_2d)
+  if (!new_texture)
     return FALSE;
 
-  *texture = COGL_TEXTURE (texture_2d);
+  *texture = new_texture;
   *changed_texture = TRUE;
   buffer->is_y_inverted = TRUE;