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mutter-performance-source/cogl/cogl-texture-driver.h
Robert Bragg 0bce7eac53 Intial Re-layout of the Cogl source code and introduction of a Cogl Winsys
As part of an incremental process to have Cogl be a standalone project we
want to re-consider how we organise the Cogl source code.

Currently this is the structure I'm aiming for:
cogl/
    cogl/
	<put common source here>
	winsys/
	   cogl-glx.c
	   cogl-wgl.c
	driver/
	    gl/
	    gles/
	os/ ?
    utils/
	cogl-fixed
	cogl-matrix-stack?
        cogl-journal?
        cogl-primitives?
    pango/

The new winsys component is a starting point for migrating window system
code (i.e.  x11,glx,wgl,osx,egl etc) from Clutter to Cogl.

The utils/ and pango/ directories aren't added by this commit, but they are
noted because I plan to add them soon.

Overview of the planned structure:

* The winsys/ API is the API that binds OpenGL to a specific window system,
  be that X11 or win32 etc.  Example are glx, wgl and egl. Much of the logic
  under clutter/{glx,osx,win32 etc} should migrate here.

* Note there is also the idea of a winsys-base that may represent a window
  system for which there are multiple winsys APIs.  An example of this is
  x11, since glx and egl may both be used with x11.  (currently only Clutter
  has the idea of a winsys-base)

* The driver/ represents a specific varient of OpenGL. Currently we have "gl"
  representing OpenGL 1.4-2.1 (mostly fixed function) and "gles" representing
  GLES 1.1 (fixed funciton) and 2.0 (fully shader based)

* Everything under cogl/ should fundamentally be supporting access to the
  GPU.  Essentially Cogl's most basic requirement is to provide a nice GPU
  Graphics API and drawing a line between this and the utility functionality
  we add to support Clutter should help keep this lean and maintainable.

* Code under utils/ as suggested builds on cogl/ adding more convenient
  APIs or mechanism to optimize special cases. Broadly speaking you can
  compare cogl/ to OpenGL and utils/ to GLU.

* clutter/pango will be moved to clutter/cogl/pango

How some of the internal configure.ac/pkg-config terminology has changed:
backendextra -> CLUTTER_WINSYS_BASE # e.g. "x11"
backendextralib -> CLUTTER_WINSYS_BASE_LIB # e.g. "x11/libclutter-x11.la"
clutterbackend -> {CLUTTER,COGL}_WINSYS # e.g. "glx"
CLUTTER_FLAVOUR -> {CLUTTER,COGL}_WINSYS
clutterbackendlib -> CLUTTER_WINSYS_LIB
CLUTTER_COGL -> COGL_DRIVER # e.g. "gl"

Note: The CLUTTER_FLAVOUR and CLUTTER_COGL defines are kept for apps

As the first thing to take advantage of the new winsys component in Cogl;
cogl_get_proc_address() has been moved from cogl/{gl,gles}/cogl.c into
cogl/common/cogl.c and this common implementation first trys
_cogl_winsys_get_proc_address() but if that fails then it falls back to
gmodule.
2009-10-16 18:58:50 +01:00

157 lines
5.7 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.
*/
#ifndef __COGL_TEXTURE_DRIVER_H
#define __COGL_TEXTURE_DRIVER_H
/*
* Basically just a wrapper around glBindTexture, but the GLES2 backend
* for example also wants to know about the internal format so it can
* identify when alpha only textures are bound.
*/
void
_cogl_texture_driver_bind (GLenum gl_target, GLuint gl_handle, GLenum gl_intformat);
/*
* This sets up the glPixelStore state for an upload to a destination with
* the same size, and with no offset.
*/
/* NB: GLES can't upload a sub region of pixel data from a larger source
* buffer which is why this interface is limited. The GL driver has a more
* flexible version of this function that is uses internally */
void
_cogl_texture_driver_prep_gl_for_pixels_upload (int pixels_rowstride,
int pixels_bpp);
/*
* This uploads a sub-region from source_bmp to a single GL texture handle (i.e
* a single CoglTexture slice)
*
* It also updates the array of tex->first_pixels[slice_index] if
* dst_{x,y} == 0
*
* The driver abstraction is in place because GLES doesn't support the pixel
* store options required to source from a subregion, so for GLES we have
* to manually create a transient source bitmap.
*
* XXX: sorry for the ridiculous number of arguments :-(
*/
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);
/*
* This sets up the glPixelStore state for an download to a destination with
* the same size, and with no offset.
*/
/* NB: GLES can't download pixel data into a sub region of a larger destination
* buffer, the GL driver has a more flexible version of this function that it
* uses internally. */
void
_cogl_texture_driver_prep_gl_for_pixels_download (int pixels_rowstride,
int pixels_bpp);
/*
* This driver abstraction is in place because GLES doesn't have a sane way to
* download data from a texture so you litterally render the texture to the
* backbuffer, and retrive the data using glReadPixels :-(
*/
gboolean
_cogl_texture_driver_download_from_gl (CoglTexture *tex,
CoglBitmap *target_bmp,
GLuint target_gl_format,
GLuint target_gl_type);
/*
* It may depend on the driver as to what texture sizes are supported...
*/
gboolean
_cogl_texture_driver_size_supported (GLenum gl_target,
GLenum gl_format,
GLenum gl_type,
int width,
int height);
/*
* This driver abstraction is needed because GLES doesn't support setting
* a texture border color.
*/
void
_cogl_texture_driver_try_setting_gl_border_color (
GLuint gl_target,
const GLfloat *transparent_color);
/*
* XXX: this should live in cogl/{gl,gles}/cogl.c
*/
gboolean
_cogl_pixel_format_from_gl_internal (GLenum gl_int_format,
CoglPixelFormat *out_format);
/*
* XXX: this should live in cogl/{gl,gles}/cogl.c
*/
CoglPixelFormat
_cogl_pixel_format_to_gl (CoglPixelFormat format,
GLenum *out_glintformat,
GLenum *out_glformat,
GLenum *out_gltype);
/*
* It may depend on the driver as to what texture targets may be used when
* creating a foreign texture. E.g. OpenGL supports ARB_texture_rectangle
* but GLES doesn't
*/
gboolean
_cogl_texture_driver_allows_foreign_gl_target (GLenum gl_target);
/*
* glGenerateMipmap semantics may need to be emulated for some drivers. E.g. by
* enabling auto mipmap generation an re-loading a number of known texels.
*/
void
_cogl_texture_driver_gl_generate_mipmaps (GLenum texture_target);
/*
* The driver may impose constraints on what formats can be used to store
* texture data read from textures. For example GLES currently only supports
* RGBA_8888, and so we need to manually convert the data if the final
* destination has another format.
*/
CoglPixelFormat
_cogl_texture_driver_find_best_gl_get_data_format (
CoglPixelFormat format,
GLenum *closest_gl_format,
GLenum *closest_gl_type);
#endif /* __COGL_TEXTURE_DRIVER_H */