mutter/cogl/driver/gl/cogl-texture-driver.c
Robert Bragg bb3a008318 [draw-buffers] First pass at overhauling Cogl's framebuffer management
Cogl's support for offscreen rendering was originally written just to support
the clutter_texture_new_from_actor API and due to lack of documentation and
several confusing - non orthogonal - side effects of using the API it wasn't
really possible to use directly.

This commit does a number of things:
- It removes {gl,gles}/cogl-fbo.{c,h} and adds shared cogl-draw-buffer.{c,h}
  files instead which should be easier to maintain.
- internally CoglFbo objects are now called CoglDrawBuffers. A
  CoglDrawBuffer is an abstract base class that is inherited from to
  implement CoglOnscreen and CoglOffscreen draw buffers.  CoglOffscreen draw
  buffers will initially be used to support the
  cogl_offscreen_new_to_texture API, and CoglOnscreen draw buffers will
  start to be used internally to represent windows as we aim to migrate some
  of Clutter's backend code to Cogl.
- It makes draw buffer objects the owners of the following state:
  - viewport
  - projection matrix stack
  - modelview matrix stack
  - clip state
(This means when you switch between draw buffers you will automatically be
 switching to their associated viewport, matrix and clip state)

Aside from hopefully making cogl_offscreen_new_to_texture be more useful
short term by having simpler and well defined semantics for
cogl_set_draw_buffer, as mentioned above this is the first step for a couple
of other things:
- Its a step toward moving ownership for windows down from Clutter backends
  into Cogl, by (internally at least) introducing the CoglOnscreen draw
  buffer.  Note: the plan is that cogl_set_draw_buffer will accept on or
  offscreen draw buffer handles, and the "target" argument will become
  redundant since we will instead query the type of the given draw buffer
  handle.
- Because we have a common type for on and offscreen framebuffers we can
  provide a unified API for framebuffer management. Things like:
  - blitting between buffers
  - managing ancillary buffers (e.g. attaching depth and stencil buffers)
  - size requisition
  - clearing
2009-11-03 17:23:03 +00:00

376 lines
11 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2007,2008,2009 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:
* Matthew Allum <mallum@openedhand.com>
* Neil Roberts <neil@linux.intel.com>
* Robert Bragg <robert@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl.h"
#include "cogl-internal.h"
#include "cogl-util.h"
#include "cogl-bitmap.h"
#include "cogl-bitmap-private.h"
#include "cogl-texture-private.h"
#include "cogl-material.h"
#include "cogl-context.h"
#include "cogl-handle.h"
#include "cogl-primitives.h"
#include <string.h>
#include <stdlib.h>
#include <math.h>
#define glGenerateMipmap ctx->drv.pf_glGenerateMipmap
void
_cogl_texture_driver_bind (GLenum gl_target,
GLuint gl_handle,
GLenum gl_intformat)
{
GE (glBindTexture (gl_target, gl_handle));
}
/* OpenGL - unlike GLES - can upload a sub region of pixel data from a larger
* source buffer */
static void
prep_gl_for_pixels_upload_full (int pixels_rowstride,
int pixels_src_x,
int pixels_src_y,
int pixels_bpp)
{
GE( glPixelStorei (GL_UNPACK_ROW_LENGTH, pixels_rowstride / pixels_bpp) );
GE( glPixelStorei (GL_UNPACK_SKIP_PIXELS, pixels_src_x) );
GE( glPixelStorei (GL_UNPACK_SKIP_ROWS, pixels_src_y) );
_cogl_texture_prep_gl_alignment_for_pixels_upload (pixels_rowstride);
}
void
_cogl_texture_driver_prep_gl_for_pixels_upload (int pixels_rowstride,
int pixels_bpp)
{
prep_gl_for_pixels_upload_full (pixels_rowstride, 0, 0, pixels_bpp);
}
/* OpenGL - unlike GLES - can download pixel data into a sub region of
* a larger destination buffer */
static void
prep_gl_for_pixels_download_full (int pixels_rowstride,
int pixels_src_x,
int pixels_src_y,
int pixels_bpp)
{
GE( glPixelStorei (GL_PACK_ROW_LENGTH, pixels_rowstride / pixels_bpp) );
GE( glPixelStorei (GL_PACK_SKIP_PIXELS, pixels_src_x) );
GE( glPixelStorei (GL_PACK_SKIP_ROWS, pixels_src_y) );
_cogl_texture_prep_gl_alignment_for_pixels_download (pixels_rowstride);
}
void
_cogl_texture_driver_prep_gl_for_pixels_download (int pixels_rowstride,
int pixels_bpp)
{
prep_gl_for_pixels_download_full (pixels_rowstride, 0, 0, pixels_bpp);
}
void
_cogl_texture_driver_upload_subregion_to_gl (CoglTexture *tex,
int src_x,
int src_y,
int dst_x,
int dst_y,
int width,
int height,
CoglBitmap *source_bmp,
GLuint source_gl_format,
GLuint source_gl_type,
GLuint gl_handle)
{
int bpp = _cogl_get_format_bpp (source_bmp->format);
/* Setup gl alignment to match rowstride and top-left corner */
prep_gl_for_pixels_upload_full (source_bmp->rowstride,
src_x,
src_y,
bpp);
/* Upload new image data */
GE( _cogl_texture_driver_bind (tex->gl_target,
gl_handle, tex->gl_intformat) );
GE( glTexSubImage2D (tex->gl_target, 0,
dst_x, dst_y,
width, height,
source_gl_format,
source_gl_type,
source_bmp->data) );
}
gboolean
_cogl_texture_driver_gl_get_tex_image (GLenum gl_target,
GLenum dest_gl_format,
GLenum dest_gl_type,
guint8 *dest)
{
GE (glGetTexImage (gl_target,
0, /* level */
dest_gl_format,
dest_gl_type,
(GLvoid *)dest));
return TRUE;
}
gboolean
_cogl_texture_driver_size_supported (GLenum gl_target,
GLenum gl_format,
GLenum gl_type,
int width,
int height)
{
if (gl_target == GL_TEXTURE_2D)
{
/* Proxy texture allows for a quick check for supported size */
GLint new_width = 0;
GE( glTexImage2D (GL_PROXY_TEXTURE_2D, 0, GL_RGBA,
width, height, 0 /* border */,
gl_format, gl_type, NULL) );
GE( glGetTexLevelParameteriv (GL_PROXY_TEXTURE_2D, 0,
GL_TEXTURE_WIDTH, &new_width) );
return new_width != 0;
}
else
{
/* not used */
return 0;
}
}
void
_cogl_texture_driver_try_setting_gl_border_color (
GLuint gl_target,
const GLfloat *transparent_color)
{
/* Use a transparent border color so that we can leave the
color buffer alone when using texture co-ordinates
outside of the texture */
GE( glTexParameterfv (gl_target, GL_TEXTURE_BORDER_COLOR,
transparent_color) );
}
gboolean
_cogl_pixel_format_from_gl_internal (GLenum gl_int_format,
CoglPixelFormat *out_format)
{
/* It doesn't really matter we convert to exact same
format (some have no cogl match anyway) since format
is re-matched against cogl when getting or setting
texture image data.
*/
switch (gl_int_format)
{
case GL_ALPHA: case GL_ALPHA4: case GL_ALPHA8:
case GL_ALPHA12: case GL_ALPHA16:
*out_format = COGL_PIXEL_FORMAT_A_8;
return TRUE;
case GL_LUMINANCE: case GL_LUMINANCE4: case GL_LUMINANCE8:
case GL_LUMINANCE12: case GL_LUMINANCE16:
*out_format = COGL_PIXEL_FORMAT_G_8;
return TRUE;
case GL_RGB: case GL_RGB4: case GL_RGB5: case GL_RGB8:
case GL_RGB10: case GL_RGB12: case GL_RGB16: case GL_R3_G3_B2:
*out_format = COGL_PIXEL_FORMAT_RGB_888;
return TRUE;
case GL_RGBA: case GL_RGBA2: case GL_RGBA4: case GL_RGB5_A1:
case GL_RGBA8: case GL_RGB10_A2: case GL_RGBA12: case GL_RGBA16:
*out_format = COGL_PIXEL_FORMAT_RGBA_8888;
return TRUE;
}
return FALSE;
}
CoglPixelFormat
_cogl_pixel_format_to_gl (CoglPixelFormat format,
GLenum *out_glintformat,
GLenum *out_glformat,
GLenum *out_gltype)
{
CoglPixelFormat required_format;
GLenum glintformat = 0;
GLenum glformat = 0;
GLenum gltype = 0;
/* FIXME: check YUV support */
required_format = format;
/* Find GL equivalents */
switch (format & COGL_UNPREMULT_MASK)
{
case COGL_PIXEL_FORMAT_A_8:
glintformat = GL_ALPHA;
glformat = GL_ALPHA;
gltype = GL_UNSIGNED_BYTE;
break;
case COGL_PIXEL_FORMAT_G_8:
glintformat = GL_LUMINANCE;
glformat = GL_LUMINANCE;
gltype = GL_UNSIGNED_BYTE;
break;
case COGL_PIXEL_FORMAT_RGB_888:
glintformat = GL_RGB;
glformat = GL_RGB;
gltype = GL_UNSIGNED_BYTE;
break;
case COGL_PIXEL_FORMAT_BGR_888:
glintformat = GL_RGB;
glformat = GL_BGR;
gltype = GL_UNSIGNED_BYTE;
break;
case COGL_PIXEL_FORMAT_RGBA_8888:
glintformat = GL_RGBA;
glformat = GL_RGBA;
gltype = GL_UNSIGNED_BYTE;
break;
case COGL_PIXEL_FORMAT_BGRA_8888:
glintformat = GL_RGBA;
glformat = GL_BGRA;
gltype = GL_UNSIGNED_BYTE;
break;
/* The following two types of channel ordering
* have no GL equivalent unless defined using
* system word byte ordering */
case COGL_PIXEL_FORMAT_ARGB_8888:
glintformat = GL_RGBA;
glformat = GL_BGRA;
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
gltype = GL_UNSIGNED_INT_8_8_8_8;
#else
gltype = GL_UNSIGNED_INT_8_8_8_8_REV;
#endif
break;
case COGL_PIXEL_FORMAT_ABGR_8888:
glintformat = GL_RGBA;
glformat = GL_RGBA;
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
gltype = GL_UNSIGNED_INT_8_8_8_8;
#else
gltype = GL_UNSIGNED_INT_8_8_8_8_REV;
#endif
break;
/* The following three types of channel ordering
* are always defined using system word byte
* ordering (even according to GLES spec) */
case COGL_PIXEL_FORMAT_RGB_565:
glintformat = GL_RGB;
glformat = GL_RGB;
gltype = GL_UNSIGNED_SHORT_5_6_5;
break;
case COGL_PIXEL_FORMAT_RGBA_4444:
glintformat = GL_RGBA;
glformat = GL_RGBA;
gltype = GL_UNSIGNED_SHORT_4_4_4_4;
break;
case COGL_PIXEL_FORMAT_RGBA_5551:
glintformat = GL_RGBA;
glformat = GL_RGBA;
gltype = GL_UNSIGNED_SHORT_5_5_5_1;
break;
/* FIXME: check extensions for YUV support */
default:
break;
}
if (out_glintformat != NULL)
*out_glintformat = glintformat;
if (out_glformat != NULL)
*out_glformat = glformat;
if (out_gltype != NULL)
*out_gltype = gltype;
return required_format;
}
gboolean
_cogl_texture_driver_allows_foreign_gl_target (GLenum gl_target)
{
/* GL_ARB_texture_rectangle textures are supported if they are
created from foreign because some chipsets have trouble with
GL_ARB_texture_non_power_of_two. There is no Cogl call to create
them directly to emphasize the fact that they don't work fully
(for example, no mipmapping and complicated shader support) */
/* Allow 2-dimensional or rectangle textures only */
if (gl_target != GL_TEXTURE_2D && gl_target != CGL_TEXTURE_RECTANGLE_ARB)
return FALSE;
return TRUE;
}
void
_cogl_texture_driver_gl_generate_mipmaps (GLenum gl_target)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
GE( glGenerateMipmap (gl_target) );
}
CoglPixelFormat
_cogl_texture_driver_find_best_gl_get_data_format (
CoglPixelFormat format,
GLenum *closest_gl_format,
GLenum *closest_gl_type)
{
/* Find closest format that's supported by GL */
return _cogl_pixel_format_to_gl (format,
NULL, /* don't need */
closest_gl_format,
closest_gl_type);
}