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/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/*
* MetaTextureTower
*
* Mipmap emulation by creation of scaled down images
*
* Copyright (C) 2009 Red Hat, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __META_TEXTURE_TOWER_H__
#define __META_TEXTURE_TOWER_H__
#include <clutter/clutter.h>
G_BEGIN_DECLS
/**
* SECTION:MetaTextureTower
* @short_description: mipmap emulation by creation of scaled down images
*
* A #MetaTextureTower is used to get good looking scaled down images when
* we can't use the GL drivers mipmap support. There are two separate reasons
*
* - Some cards (including radeon cards <= r5xx) only support
* TEXTURE_RECTANGLE_ARB and not NPOT textures. Rectangular textures
* are defined not to support mipmapping.
* - Even when NPOT textures are available, the combination of NPOT
* textures, texture_from_pixmap, and mipmapping doesn't typically
* work, since the X server doesn't allocate pixmaps in the right
* layout for mipmapping.
*
* So, what we do is create the "mipmap" levels ourselves by successive
* power-of-two scaledowns, and when rendering pick the single texture
* that best matches the scale we are rendering at. (Since we aren't
* typically using perspective transforms, we'll frequently have a single
* scale for the entire texture.)
*/
typedef struct _MetaTextureTower MetaTextureTower;
MetaTextureTower *meta_texture_tower_new (void);
void meta_texture_tower_free (MetaTextureTower *tower);
void meta_texture_tower_set_base_texture (MetaTextureTower *tower,
CoglTexture *texture);
void meta_texture_tower_update_area (MetaTextureTower *tower,
int x,
int y,
int width,
int height);
CoglTexture *meta_texture_tower_get_paint_texture (MetaTextureTower *tower);
G_BEGIN_DECLS
#endif /* __META_TEXTURE_TOWER_H__ */
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