mutter/cogl/cogl-buffer.h
Neil Roberts 6027aa04a4 cogl-buffer: Use void* instead of guint8* for map and set_data
Unless the CoglBuffer is being used for texture data then it's
relatively unlikely that the data will contain an array of bytes. For
example if it's used as a vertex array then it's more likely to be
floats or some vertex struct. In that case it's much more convenient
if set_data and map use void* pointers so that we can avoid a cast.
2010-11-04 18:04:03 +00:00

243 lines
6.9 KiB
C

/*
* 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, see <http://www.gnu.org/licenses/>.
*
*
*
* Authors:
* Damien Lespiau <damien.lespiau@intel.com>
* Robert Bragg <robert@linux.intel.com>
*/
#if !defined(__COGL_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_BUFFER_H__
#define __COGL_BUFFER_H__
#include <glib.h>
#include <cogl/cogl-types.h>
G_BEGIN_DECLS
/**
* SECTION:cogl-buffer
* @short_description: Buffer creation and manipulation
* @stability: Unstable
*
* COGL allows the creation and the manipulation of buffers. If the underlying
* OpenGL implementation allows it, COGL will use Pixel Buffer Objects.
*/
/* All of the cogl-buffer API is currently experimental so we suffix
* the actual symbols with _EXP so if somone is monitoring for ABI
* changes it will hopefully be clearer to them what's going on if any
* of the symbols dissapear at a later date.
*/
#define cogl_is_buffer cogl_is_buffer_EXP
#define cogl_buffer_get_size cogl_buffer_get_size_EXP
#define cogl_buffer_set_usage_hint cogl_buffer_set_usage_hint_EXP
#define cogl_buffer_get_usage_hint cogl_buffer_get_usage_hint_EXP
#define cogl_buffer_set_update_hint cogl_buffer_set_update_hint_EXP
#define cogl_buffer_get_update_hint cogl_buffer_get_update_hint_EXP
#define cogl_buffer_map cogl_buffer_map_EXP
#define cogl_buffer_unmap cogl_buffer_unmap_EXP
#define cogl_buffer_set_data cogl_buffer_set_data_EXP
typedef struct _CoglBuffer CoglBuffer;
/**
* cogl_is_buffer:
* @buffer: a buffer object
*
* Checks whether @buffer is a buffer object.
*
* Return value: %TRUE if the handle is a CoglBuffer, and %FALSE otherwise
*
* Since: 1.2
* Stability: Unstable
*/
gboolean
cogl_is_buffer (const void *object);
/**
* cogl_buffer_get_size:
* @buffer: a buffer object
*
* Retrieves the size of buffer
*
* Return value: the size of the buffer in bytes
*
* Since: 1.2
* Stability: Unstable
*/
unsigned int
cogl_buffer_get_size (CoglBuffer *buffer);
/**
* CoglBufferUpdateHint:
* @COGL_BUFFER_UPDATE_HINT_STATIC: the buffer will not change over time
* @COGL_BUFFER_UPDATE_HINT_DYNAMIC: the buffer will change from time to time
* @COGL_BUFFER_UPDATE_HINT_STREAM: the buffer will be used once or a couple of
* times
*
* The update hint on a buffer allows the user to give some detail on how often
* the buffer data is going to be updated.
*
* Since: 1.2
* Stability: Unstable
*/
typedef enum { /*< prefix=COGL_BUFFER_UPDATE_HINT >*/
COGL_BUFFER_UPDATE_HINT_STATIC,
COGL_BUFFER_UPDATE_HINT_DYNAMIC,
COGL_BUFFER_UPDATE_HINT_STREAM
} CoglBufferUpdateHint;
/**
* cogl_buffer_set_update_hint:
* @buffer: a buffer object
* @hint: the new hint
*
* Sets the update hint on a buffer. See #CoglBufferUpdateHint for a description
* of the available hints.
*
* Since: 1.2
* Stability: Unstable
*/
void
cogl_buffer_set_update_hint (CoglBuffer *buffer,
CoglBufferUpdateHint hint);
/**
* cogl_buffer_get_update_hint:
* @buffer: a buffer object
*
* Retrieves the update hints set using cogl_buffer_set_update_hint()
*
* Return value: the #CoglBufferUpdateHint currently used by the buffer
*
* Since: 1.2
* Stability: Unstable
*/
CoglBufferUpdateHint
cogl_buffer_get_update_hint (CoglBuffer *buffer);
/**
* CoglBufferAccess:
* @COGL_BUFFER_ACCESS_READ: the buffer will be read
* @COGL_BUFFER_ACCESS_WRITE: the buffer will written to
* @COGL_BUFFER_ACCESS_READ_WRITE: the buffer will be used for both reading and
* writing
*
* The access hints for cogl_buffer_set_update_hint()
*
* Since: 1.2
* Stability: Unstable
*/
typedef enum { /*< prefix=COGL_BUFFER_ACCESS >*/
COGL_BUFFER_ACCESS_READ = 1 << 0,
COGL_BUFFER_ACCESS_WRITE = 1 << 1,
COGL_BUFFER_ACCESS_READ_WRITE = COGL_BUFFER_ACCESS_READ | COGL_BUFFER_ACCESS_WRITE
} CoglBufferAccess;
/**
* CoglBufferMapHint:
* COGL_BUFFER_MAP_HINT_DISCARD: Tells Cogl that you plan to replace
* all the buffer's contents.
*
* Hints to Cogl about how you are planning to modify the data once it
* is mapped.
*
* Since: 1.4
* Stability: Unstable
*/
typedef enum { /*< prefix=COGL_BUFFER_MAP_HINT >*/
COGL_BUFFER_MAP_HINT_DISCARD = 1 << 0
} CoglBufferMapHint;
/**
* cogl_buffer_map:
* @buffer: a buffer object
* @access: how the mapped buffer will be used by the application
* @hints: A mask of #CoglBufferMapHint<!-- -->s that tell Cogl how
* the data will be modified once mapped.
*
* Maps the buffer into the application address space for direct access.
*
* It is strongly recommended that you pass
* %COGL_BUFFER_MAP_HINT_DISCARD as a hint if you are going to replace
* all the buffer's data. This way if the buffer is currently being
* used by the GPU then the driver won't have to stall the CPU and
* wait for the hardware to finish because it can instead allocate a
* new buffer to map.
*
* The behaviour is undefined if you access the buffer in a way
* conflicting with the @access mask you pass. It is also an error to
* release your last reference while the buffer is mapped.
*
* Return value: A pointer to the mapped memory or %NULL is the call fails
*
* Since: 1.2
* Stability: Unstable
*/
void *
cogl_buffer_map (CoglBuffer *buffer,
CoglBufferAccess access,
CoglBufferMapHint hints);
/**
* cogl_buffer_unmap:
* @buffer: a buffer object
*
* Unmaps a buffer previously mapped by cogl_buffer_map().
*
* Since: 1.2
* Stability: Unstable
*/
void
cogl_buffer_unmap (CoglBuffer *buffer);
/**
* cogl_buffer_set_data:
* @buffer: a buffer object
* @offset: destination offset (in bytes) in the buffer
* @data: a pointer to the data to be copied into the buffer
* @size: number of bytes to copy
*
* Updates part of the buffer with new data from @data. Where to put this new
* data is controlled by @offset and @offset + @data should be less than the
* buffer size.
*
* Return value: %TRUE is the operation succeeded, %FALSE otherwise
*
* Since: 1.2
* Stability: Unstable
*/
gboolean
cogl_buffer_set_data (CoglBuffer *buffer,
gsize offset,
const void *data,
gsize size);
G_END_DECLS
#endif /* __COGL_BUFFER_H__ */