brl/mutter
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

cogl-material: Compare whether textures are equal by their GL handle

Browse Source 
Textures within a layer were compared for equality by comparing their
texture handle. However this means that sub textures and atlas
textures which may be internally using the same GL handle would not be
batched together. Instead it now tries to determine the underlying GL
handle using either the slice override or _cogl_texture_get_gl_texture
and then compares those.
This commit is contained in:
Neil Roberts 2010-08-12 09:11:28 +01:00
parent 8538bdbdea
commit 89c535f50d
1 changed files with 26 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
clutter/cogl/cogl/cogl-material.c
View File

@ -2640,18 +2640,26 @@ static gboolean
_cogl_material_layer_texture_equal (CoglMaterialLayer *authority0,
CoglMaterialLayer *authority1)
{
if (authority0->texture != authority1->texture)
return FALSE;
GLuint gl_handle0, gl_handle1;
GLenum gl_target0, gl_target1;
if (authority0->texture_overridden != authority1->texture_overridden)
return FALSE;
if (authority0->texture_overridden)
{
gl_handle0 = authority0->slice_gl_texture;
gl_target0 = authority0->slice_gl_target;
}
else
cogl_texture_get_gl_texture (authority0->texture, &gl_handle0, &gl_target0);
if (authority0->texture_overridden &&
(authority0->slice_gl_texture != authority1->slice_gl_texture ||
authority0->slice_gl_target != authority1->slice_gl_target))
return FALSE;
if (authority1->texture_overridden)
{
gl_handle1 = authority1->slice_gl_texture;
gl_target1 = authority1->slice_gl_target;
}
else
cogl_texture_get_gl_texture (authority1->texture, &gl_handle1, &gl_target1);
return TRUE;
return gl_handle0 == gl_handle1 && gl_target0 == gl_target1;
}
/* Determine the mask of differences between two layers.
@ -3183,6 +3191,15 @@ simple_property_equal (CoglMaterial *material0,
* It is acceptable to have false negatives - although they will result
* in redundant OpenGL calls that try and update the state.
*
* When comparing texture layers, _cogl_material_equal will actually
* compare the underlying GL texture handle that the Cogl texture uses
* so that atlas textures and sub textures will be considered equal if
* they point to the same texture. This is useful for comparing
* materials in the journal but it means that _cogl_material_equal
* doesn't strictly compare whether the materials are the same. If we
* needed those semantics we could perhaps add another function or
* some flags to control the behaviour.
*
* False positives aren't allowed.
*/
gboolean