/**
* meta_create_texture_material:
* @src_texture: (allow-none): texture to use initially for the layer
*
* Creates a material with a single layer. Using a common template
* allows sharing a shader for different uses in Muffin. To share the same
* shader with all other materials that are just texture plus opacity
* would require Cogl fixes.
* (See http://bugzilla.clutter-project.org/show_bug.cgi?id=2425)
*
* Return value: (transfer full): a newly created Cogl material
*/
CoglHandle
meta_create_texture_material (CoglHandle src_texture)
{
static CoglHandle texture_material_template = COGL_INVALID_HANDLE;
CoglHandle material;
/* We use a material that has a dummy texture as a base for all
texture materials. The idea is that only the Cogl texture object
would be different in the children so it is likely that Cogl will
be able to share GL programs between all the textures. */
if (G_UNLIKELY (texture_material_template == COGL_INVALID_HANDLE))
{
CoglHandle dummy_texture;
dummy_texture = meta_create_color_texture_4ub (0xff, 0xff, 0xff, 0xff,
COGL_TEXTURE_NONE);
texture_material_template = cogl_material_new ();
cogl_material_set_layer (texture_material_template, 0, dummy_texture);
cogl_handle_unref (dummy_texture);
}
material = cogl_material_copy (texture_material_template);
if (src_texture != COGL_INVALID_HANDLE)
cogl_material_set_layer (material, 0, src_texture);
return material;
}
/* Sets our material to paint with a 1x1 texture of the stage's background
* color; doing this when we have no pixmap allows the application to turn
* off painting the stage. There might be a performance benefit to
* painting in this case with a solid color, but the normal solid color
* case is a 1x1 root pixmap, so we'd have to reverse-engineer that to
* actually pick up the (small?) performance win. This is just a fallback.
*/
static void
set_texture_to_stage_color (MetaScreenBackground *background)
{
ClutterActor *stage = meta_get_stage_for_screen (background->screen);
ClutterColor color;
CoglHandle texture;
clutter_stage_get_color (CLUTTER_STAGE (stage), &color);
/* Slicing will prevent COGL from using hardware texturing for
* the tiled 1x1 pixmap, and will cause it to draw the window
* background in millions of separate 1x1 rectangles */
texture = meta_create_color_texture_4ub (color.red, color.green,
color.blue, 0xff,
COGL_TEXTURE_NO_SLICING);
set_texture (background, texture);
cogl_handle_unref (texture);
}
