Add _cogl_texture_get_type()

This adds an internal function to get the type of the underlying
hardware texture for any CoglTexture. It can return one of three
values to represent 2D textures, 3D textures or rectangle textures.
The idea is that this can be used as a replacement for
cogl_texture_get_gl_texture when only the target is required to make
it a bit less GL-centric. The implementation adds a new virtual
function which all of the texture backends now implement.

The enum is in a public header because a later patch will want to use
it from the CoglPipeline API. We may want to consider making the
function public too later.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

cogl/cogl-atlas-texture.c

@@ -809,6 +809,12 @@ _cogl_atlas_texture_remove_reorganize_callback (GHookFunc callback,
     g_hook_destroy_link (&ctx->atlas_reorganize_callbacks, hook);
 }
 
+static CoglTextureType
+_cogl_atlas_texture_get_type (CoglTexture *tex)
+{
+  return COGL_TEXTURE_TYPE_2D;
+}
+
 static const CoglTextureVtable
 cogl_atlas_texture_vtable =
   {
@@ -829,5 +835,6 @@ cogl_atlas_texture_vtable =
     _cogl_atlas_texture_get_gl_format,
     _cogl_atlas_texture_get_width,
     _cogl_atlas_texture_get_height,
+    _cogl_atlas_texture_get_type,
     NULL /* is_foreign */
   };

cogl/cogl-sub-texture.c

@@ -416,6 +416,14 @@ _cogl_sub_texture_get_height (CoglTexture *tex)
   return sub_tex->sub_height;
 }
 
+static CoglTextureType
+_cogl_sub_texture_get_type (CoglTexture *tex)
+{
+  CoglSubTexture *sub_tex = COGL_SUB_TEXTURE (tex);
+
+  return _cogl_texture_get_type (sub_tex->full_texture);
+}
+
 static const CoglTextureVtable
 cogl_sub_texture_vtable =
   {
@@ -436,5 +444,6 @@ cogl_sub_texture_vtable =
     _cogl_sub_texture_get_gl_format,
     _cogl_sub_texture_get_width,
     _cogl_sub_texture_get_height,
+    _cogl_sub_texture_get_type,
     NULL /* is_foreign */
   };

cogl/cogl-texture-2d-sliced.c

@@ -1293,6 +1293,12 @@ _cogl_texture_2d_sliced_get_height (CoglTexture *tex)
   return COGL_TEXTURE_2D_SLICED (tex)->height;
 }
 
+static CoglTextureType
+_cogl_texture_2d_sliced_get_type (CoglTexture *tex)
+{
+  return COGL_TEXTURE_TYPE_2D;
+}
+
 static const CoglTextureVtable
 cogl_texture_2d_sliced_vtable =
   {
@@ -1313,5 +1319,6 @@ cogl_texture_2d_sliced_vtable =
     _cogl_texture_2d_sliced_get_gl_format,
     _cogl_texture_2d_sliced_get_width,
     _cogl_texture_2d_sliced_get_height,
+    _cogl_texture_2d_sliced_get_type,
     _cogl_texture_2d_sliced_is_foreign
   };

cogl/cogl-texture-2d.c

@@ -859,6 +859,12 @@ _cogl_texture_2d_is_foreign (CoglTexture *tex)
   return COGL_TEXTURE_2D (tex)->is_foreign;
 }
 
+static CoglTextureType
+_cogl_texture_2d_get_type (CoglTexture *tex)
+{
+  return COGL_TEXTURE_TYPE_2D;
+}
+
 static const CoglTextureVtable
 cogl_texture_2d_vtable =
   {
@@ -879,5 +885,6 @@ cogl_texture_2d_vtable =
     _cogl_texture_2d_get_gl_format,
     _cogl_texture_2d_get_width,
     _cogl_texture_2d_get_height,
+    _cogl_texture_2d_get_type,
     _cogl_texture_2d_is_foreign
   };

cogl/cogl-texture-3d.c

@@ -592,6 +592,12 @@ _cogl_texture_3d_get_height (CoglTexture *tex)
   return COGL_TEXTURE_3D (tex)->height;
 }
 
+static CoglTextureType
+_cogl_texture_3d_get_type (CoglTexture *tex)
+{
+  return COGL_TEXTURE_TYPE_3D;
+}
+
 static const CoglTextureVtable
 cogl_texture_3d_vtable =
   {
@@ -612,5 +618,6 @@ cogl_texture_3d_vtable =
     _cogl_texture_3d_get_gl_format,
     _cogl_texture_3d_get_width,
     _cogl_texture_3d_get_height,
+    _cogl_texture_3d_get_type,
     NULL /* is_foreign */
   };

cogl/cogl-texture-private.h

@@ -121,6 +121,8 @@ struct _CoglTextureVtable
   int (* get_width) (CoglTexture *tex);
   int (* get_height) (CoglTexture *tex);
 
+  CoglTextureType (* get_type) (CoglTexture *tex);
+
   gboolean (* is_foreign) (CoglTexture *tex);
 };
 
@@ -274,4 +276,16 @@ _cogl_texture_spans_foreach_in_region (CoglSpan *x_spans,
                                        CoglMetaTextureCallback callback,
                                        void *user_data);
 
+/*
+ * _cogl_texture_get_type:
+ * @texture: a #CoglTexture pointer
+ *
+ * Retrieves the texture type of the underlying hardware texture that
+ * this #CoglTexture will use.
+ *
+ * Return value: The type of the hardware texture.
+ */
+CoglTextureType
+_cogl_texture_get_type (CoglTexture *texture);
+
 #endif /* __COGL_TEXTURE_PRIVATE_H */

cogl/cogl-texture-rectangle.c

@@ -579,6 +579,12 @@ _cogl_texture_rectangle_is_foreign (CoglTexture *tex)
   return COGL_TEXTURE_RECTANGLE (tex)->is_foreign;
 }
 
+static CoglTextureType
+_cogl_texture_rectangle_get_type (CoglTexture *tex)
+{
+  return COGL_TEXTURE_TYPE_RECTANGLE;
+}
+
 static const CoglTextureVtable
 cogl_texture_rectangle_vtable =
   {
@@ -599,5 +605,6 @@ cogl_texture_rectangle_vtable =
     _cogl_texture_rectangle_get_gl_format,
     _cogl_texture_rectangle_get_width,
     _cogl_texture_rectangle_get_height,
+    _cogl_texture_rectangle_get_type,
     _cogl_texture_rectangle_is_foreign
   };

cogl/cogl-texture.c

@@ -643,6 +643,12 @@ cogl_texture_get_gl_texture (CoglTexture *texture,
                                           out_gl_handle, out_gl_target);
 }
 
+CoglTextureType
+_cogl_texture_get_type (CoglTexture *texture)
+{
+  return texture->vtable->get_type (texture);
+}
+
 void
 _cogl_texture_set_filters (CoglTexture *texture,
                            GLenum min_filter,

cogl/cogl-texture.h

@@ -78,6 +78,24 @@ typedef enum {
   COGL_TEXTURE_ERROR_TYPE
 } CoglTextureError;
 
+/**
+ * CoglTextureType:
+ * @COGL_TEXTURE_TYPE_2D: A #CoglTexture2D
+ * @COGL_TEXTURE_TYPE_3D: A #CoglTexture3D
+ * @COGL_TEXTURE_TYPE_RECTANGLE: A #CoglTextureRectangle
+ *
+ * Constants representing the underlying hardware texture type of a
+ * #CoglTexture.
+ *
+ * Stability: unstable
+ * Since: 1.10
+ */
+typedef enum {
+  COGL_TEXTURE_TYPE_2D,
+  COGL_TEXTURE_TYPE_3D,
+  COGL_TEXTURE_TYPE_RECTANGLE
+} CoglTextureType;
+
 GQuark cogl_texture_error_quark (void);
 
 /**

cogl/winsys/cogl-texture-pixmap-x11.c

@@ -998,6 +998,18 @@ _cogl_texture_pixmap_x11_get_height (CoglTexture *tex)
   return tex_pixmap->height;
 }
 
+static CoglTextureType
+_cogl_texture_pixmap_x11_get_type (CoglTexture *tex)
+{
+  CoglTexturePixmapX11 *tex_pixmap = COGL_TEXTURE_PIXMAP_X11 (tex);
+  CoglTexture *child_tex;
+
+  child_tex = _cogl_texture_pixmap_x11_get_texture (tex_pixmap);
+
+  /* Forward on to the child texture */
+  return _cogl_texture_get_type (child_tex);
+}
+
 static void
 _cogl_texture_pixmap_x11_free (CoglTexturePixmapX11 *tex_pixmap)
 {
@@ -1049,5 +1061,6 @@ cogl_texture_pixmap_x11_vtable =
     _cogl_texture_pixmap_x11_get_gl_format,
     _cogl_texture_pixmap_x11_get_width,
     _cogl_texture_pixmap_x11_get_height,
+    _cogl_texture_pixmap_x11_get_type,
     NULL /* is_foreign */
   };

doc/reference/cogl-2.0-experimental/cogl-2.0-experimental-sections.txt

@@ -318,6 +318,7 @@ cogl_texture_get_format
 cogl_texture_is_sliced
 cogl_texture_get_data
 cogl_texture_set_region
+CoglTextureType
 
 <SUBSECTION Private>
 COGL_TEXTURE_MAX_WASTE