mutter/cogl/cogl-sub-texture.h

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/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2010 Intel Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Authors:
* Neil Roberts <neil@linux.intel.com>
*/
#if !defined(__COGL_H_INSIDE__) && !defined(COGL_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_SUB_TEXTURE_H
#define __COGL_SUB_TEXTURE_H
COGL_BEGIN_DECLS
/**
* SECTION:cogl-sub-texture
* @short_description: Functions for creating and manipulating
* sub-textures.
*
* These functions allow high-level textures to be created that
* represent a sub-region of another texture. For example these
* can be used to implement custom texture atlasing schemes.
*/
#define COGL_SUB_TEXTURE(tex) ((CoglSubTexture *) tex)
typedef struct _CoglSubTexture CoglSubTexture;
/**
* cogl_sub_texture_new:
* @context: A #CoglContext pointer
* @parent_texture: The full texture containing a sub-region you want
* to make a #CoglSubTexture from.
* @sub_x: The top-left x coordinate of the parent region to make
* a texture from.
* @sub_y: The top-left y coordinate of the parent region to make
* a texture from.
* @sub_width: The width of the parent region to make a texture from.
* @sub_height: The height of the parent region to make a texture
* from.
*
* Creates a high-level #CoglSubTexture representing a sub-region of
* any other #CoglTexture. The sub-region must strictly lye within the
* bounds of the @parent_texture. The returned texture implements the
* #CoglMetaTexture interface because it's not a low level texture
* that hardware can understand natively.
*
* <note>Remember: Unless you are using high level drawing APIs such
* as cogl_rectangle() or other APIs documented to understand the
* #CoglMetaTexture interface then you need to use the
* #CoglMetaTexture interface to resolve a #CoglSubTexture into a
* low-level texture before drawing.</note>
*
* Returns: A newly allocated #CoglSubTexture representing a
* sub-region of @parent_texture.
*
* Since: 1.10
* Stability: unstable
*/
CoglSubTexture *
cogl_sub_texture_new (CoglContext *ctx,
CoglTexture *parent_texture,
int sub_x,
int sub_y,
int sub_width,
int sub_height);
/**
* cogl_sub_texture_get_parent:
* @sub_texture: A pointer to a #CoglSubTexture
*
* Retrieves the parent texture that @sub_texture derives its content
* from. This is the texture that was passed to
* cogl_sub_texture_new() as the parent_texture argument.
*
* Return value: (transfer none): The parent texture that @sub_texture
* derives its content from.
* Since: 1.10
* Stability: unstable
*/
CoglTexture *
cogl_sub_texture_get_parent (CoglSubTexture *sub_texture);
/**
* cogl_is_sub_texture:
* @object: a #CoglObject
*
* Checks whether @object is a #CoglSubTexture.
*
* Return value: %TRUE if the passed @object represents a
* #CoglSubTexture and %FALSE otherwise.
*
* Since: 1.10
* Stability: unstable
*/
CoglBool
cogl_is_sub_texture (void *object);
COGL_END_DECLS
#endif /* __COGL_SUB_TEXTURE_H */