mutter/cogl/cogl-bitmap-private.h
Neil Roberts 0b2dc74dbc cogl-texture: Don't use the source rowstride if we have to copy bitmap
If we have to copy the bitmap to do the premultiplication then we were
previously using the rowstride of the source image as the rowstride
for the new image. This is wasteful if the source image is a subregion
of a larger image which would make it use a large rowstride. If we
have to copy the data anyway we might as well compact it to the
smallest rowstride. This also prevents the copy from reading past the
end of the last row of pixels.

An internal function called _cogl_bitmap_copy has been added to do the
copy. It creates a new bitmap with the smallest possible rowstride
rounded up the nearest multiple of 4 bytes. There may be other places
in Cogl that are currently assuming we can read height*rowstride of
the source buffer so they may want to take advantage of this function
too.

http://bugzilla.clutter-project.org/show_bug.cgi?id=2491
2011-01-10 16:54:58 +00:00

206 lines
6.4 KiB
C

/*
* Clutter COGL
*
* A basic GL/GLES Abstraction/Utility Layer
*
* Authored By Matthew Allum <mallum@openedhand.com>
*
* Copyright (C) 2007 OpenedHand
*
* 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/>.
*
*
*/
#ifndef __COGL_BITMAP_H
#define __COGL_BITMAP_H
#include <glib.h>
#include "cogl-handle.h"
#include "cogl-buffer.h"
/*
* CoglBitmapDestroyNotify:
* @data: The image data
* @destroy_data: The callback closure data that was given to
* _cogl_bitmap_new_from_data().
*
* Function prototype that is used to destroy the bitmap data when
* _cogl_bitmap_new_from_data() is called.
*/
typedef void (* CoglBitmapDestroyNotify) (guint8 *data, void *destroy_data);
/*
* _cogl_bitmap_new_from_data:
* @data: A pointer to the data. The bitmap will take ownership of this data.
* @format: The format of the pixel data.
* @width: The width of the bitmap.
* @height: The height of the bitmap.
* @rowstride: The rowstride of the bitmap (the number of bytes from
* the start of one row of the bitmap to the next).
* @destroy_fn: A function to be called when the bitmap is
* destroyed. This should free @data. %NULL can be used instead if
* no free is needed.
* @destroy_fn_data: This pointer will get passed to @destroy_fn.
*
* Creates a bitmap using some existing data. The data is not copied
* so the bitmap will take ownership of the data pointer. When the
* bitmap is freed @destroy_fn will be called to free the data.
*
* Return value: A new %CoglBitmap.
*/
CoglBitmap *
_cogl_bitmap_new_from_data (guint8 *data,
CoglPixelFormat format,
int width,
int height,
int rowstride,
CoglBitmapDestroyNotify destroy_fn,
gpointer destroy_fn_data);
/* The idea of this function is that it will create a bitmap that
shares the actual data with another bitmap. This is needed for the
atlas texture backend because it needs upload a bitmap to a sub
texture but override the format so that it ignores the premult
flag. */
CoglBitmap *
_cogl_bitmap_new_shared (CoglBitmap *shared_bmp,
CoglPixelFormat format,
int width,
int height,
int rowstride);
/* This creates a cogl bitmap that internally references a pixel
array. The data is not copied. _cogl_bitmap_map will divert to
mapping the pixel array */
CoglBitmap *
_cogl_bitmap_new_from_buffer (CoglBuffer *buffer,
CoglPixelFormat format,
int width,
int height,
int rowstride,
int offset);
gboolean
_cogl_bitmap_can_convert (CoglPixelFormat src, CoglPixelFormat dst);
gboolean
_cogl_bitmap_fallback_can_convert (CoglPixelFormat src, CoglPixelFormat dst);
gboolean
_cogl_bitmap_can_unpremult (CoglPixelFormat format);
gboolean
_cogl_bitmap_fallback_can_unpremult (CoglPixelFormat format);
gboolean
_cogl_bitmap_can_premult (CoglPixelFormat format);
gboolean
_cogl_bitmap_fallback_can_premult (CoglPixelFormat format);
CoglBitmap *
_cogl_bitmap_convert (CoglBitmap *bmp,
CoglPixelFormat dst_format);
CoglBitmap *
_cogl_bitmap_fallback_convert (CoglBitmap *bmp,
CoglPixelFormat dst_format);
gboolean
_cogl_bitmap_unpremult (CoglBitmap *dst_bmp);
gboolean
_cogl_bitmap_fallback_unpremult (CoglBitmap *dst_bmp);
gboolean
_cogl_bitmap_premult (CoglBitmap *dst_bmp);
gboolean
_cogl_bitmap_fallback_premult (CoglBitmap *dst_bmp);
CoglBitmap *
_cogl_bitmap_from_file (const char *filename,
GError **error);
CoglBitmap *
_cogl_bitmap_fallback_from_file (const char *filename);
gboolean
_cogl_bitmap_convert_premult_status (CoglBitmap *bmp,
CoglPixelFormat dst_format);
CoglBitmap *
_cogl_bitmap_convert_format_and_premult (CoglBitmap *bmp,
CoglPixelFormat dst_format);
void
_cogl_bitmap_copy_subregion (CoglBitmap *src,
CoglBitmap *dst,
int src_x,
int src_y,
int dst_x,
int dst_y,
int width,
int height);
/* Creates a deep copy of the source bitmap */
CoglBitmap *
_cogl_bitmap_copy (CoglBitmap *src_bmp);
gboolean
_cogl_bitmap_get_size_from_file (const char *filename,
int *width,
int *height);
CoglPixelFormat
_cogl_bitmap_get_format (CoglBitmap *bitmap);
void
_cogl_bitmap_set_format (CoglBitmap *bitmap,
CoglPixelFormat format);
int
_cogl_bitmap_get_width (CoglBitmap *bitmap);
int
_cogl_bitmap_get_height (CoglBitmap *bitmap);
int
_cogl_bitmap_get_rowstride (CoglBitmap *bitmap);
guint8 *
_cogl_bitmap_map (CoglBitmap *bitmap,
CoglBufferAccess access,
CoglBufferMapHint hints);
void
_cogl_bitmap_unmap (CoglBitmap *bitmap);
/* These two are replacements for map and unmap that should used when
the pointer is going to be passed to GL for pixel packing or
unpacking. The address might not be valid for reading if the bitmap
was created with new_from_buffer but it will however be good to
pass to glTexImage2D for example. The access should be READ for
unpacking and WRITE for packing. It can not be both */
guint8 *
_cogl_bitmap_bind (CoglBitmap *bitmap,
CoglBufferAccess access,
CoglBufferMapHint hints);
void
_cogl_bitmap_unbind (CoglBitmap *bitmap);
#endif /* __COGL_BITMAP_H */