mutter/cogl/cogl-texture-private.h
Robert Bragg 4c3dadd35e Add a strong CoglTexture type to replace CoglHandle
As part of the on going, incremental effort to purge the non type safe
CoglHandle type from the Cogl API this patch tackles most of the
CoglHandle uses relating to textures.

We'd postponed making this change for quite a while because we wanted to
have a clearer understanding of how we wanted to evolve the texture APIs
towards Cogl 2.0 before exposing type safety here which would be
difficult to change later since it would imply breaking APIs.

The basic idea that we are steering towards now is that CoglTexture
can be considered to be the most primitive interface we have for any
object representing a texture. The texture interface would provide
roughly these methods:

  cogl_texture_get_width
  cogl_texture_get_height
  cogl_texture_can_repeat
  cogl_texture_can_mipmap
  cogl_texture_generate_mipmap;
  cogl_texture_get_format
  cogl_texture_set_region
  cogl_texture_get_region

Besides the texture interface we will then start to expose types
corresponding to specific texture types: CoglTexture2D,
CoglTexture3D, CoglTexture2DSliced, CoglSubTexture, CoglAtlasTexture and
CoglTexturePixmapX11.

We will then also expose an interface for the high-level texture types
we have (such as CoglTexture2DSlice, CoglSubTexture and
CoglAtlasTexture) called CoglMetaTexture. CoglMetaTexture is an
additional interface that lets you iterate a virtual region of a meta
texture and get mappings of primitive textures to sub-regions of that
virtual region. Internally we already have this kind of abstraction for
dealing with sliced texture, sub-textures and atlas textures in a
consistent way, so this will just make that abstraction public. The aim
here is to clarify that there is a difference between primitive textures
(CoglTexture2D/3D) and some of the other high-level textures, and also
enable developers to implement primitives that can support meta textures
since they can only be used with the cogl_rectangle API currently.

The thing that's not so clean-cut with this are the texture constructors
we have currently; such as cogl_texture_new_from_file which no longer
make sense when CoglTexture is considered to be an interface.  These
will basically just become convenient factory functions and it's just a
bit unusual that they are within the cogl_texture namespace.  It's worth
noting here that all the texture type APIs will also have their own type
specific constructors so these functions will only be used for the
convenience of being able to create a texture without really wanting to
know the details of what type of texture you need.  Longer term for 2.0
we may come up with replacement names for these factory functions or the
other thing we are considering is designing some asynchronous factory
functions instead since it's so often detrimental to application
performance to be blocked waiting for a texture to be uploaded to the
GPU.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-09-21 15:27:03 +01:00

293 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, see <http://www.gnu.org/licenses/>.
*
*
*/
#ifndef __COGL_TEXTURE_PRIVATE_H
#define __COGL_TEXTURE_PRIVATE_H
#include "cogl-bitmap-private.h"
#include "cogl-handle.h"
#include "cogl-pipeline-private.h"
typedef struct _CoglTextureVtable CoglTextureVtable;
typedef void (*CoglTextureSliceCallback) (CoglTexture *texture,
const float *slice_coords,
const float *virtual_coords,
void *user_data);
typedef void (* CoglTextureManualRepeatCallback) (const float *coords,
void *user_data);
/* Encodes three possibiloities result of transforming a quad */
typedef enum {
/* quad doesn't cross the boundaries of a texture */
COGL_TRANSFORM_NO_REPEAT,
/* quad crosses boundaries, hardware wrap mode can handle */
COGL_TRANSFORM_HARDWARE_REPEAT,
/* quad crosses boundaries, needs software fallback;
* for a sliced texture, this might not actually involve
* repeating, just a quad crossing multiple slices */
COGL_TRANSFORM_SOFTWARE_REPEAT,
} CoglTransformResult;
/* Flags given to the pre_paint method */
typedef enum {
/* The texture is going to be used with filters that require
mipmapping. This gives the texture the opportunity to
automatically update the mipmap tree */
COGL_TEXTURE_NEEDS_MIPMAP = 1
} CoglTexturePrePaintFlags;
struct _CoglTextureVtable
{
/* Virtual functions that must be implemented for a texture
backend */
/* This should update the specified sub region of the texture with a
sub region of the given bitmap. The bitmap is not converted
before being passed so the implementation is expected to call
_cogl_texture_prepare_for_upload with a suitable destination
format before uploading */
gboolean (* set_region) (CoglTexture *tex,
int src_x,
int src_y,
int dst_x,
int dst_y,
unsigned int dst_width,
unsigned int dst_height,
CoglBitmap *bitmap);
/* This should copy the image data of the texture into @data. The
requested format will have been first passed through
ctx->texture_driver->find_best_gl_get_data_format so it should
always be a format that is valid for GL (ie, no conversion should
be necessary). */
gboolean (* get_data) (CoglTexture *tex,
CoglPixelFormat format,
unsigned int rowstride,
guint8 *data);
void (* foreach_sub_texture_in_region) (CoglTexture *tex,
float virtual_tx_1,
float virtual_ty_1,
float virtual_tx_2,
float virtual_ty_2,
CoglTextureSliceCallback callback,
void *user_data);
int (* get_max_waste) (CoglTexture *tex);
gboolean (* is_sliced) (CoglTexture *tex);
gboolean (* can_hardware_repeat) (CoglTexture *tex);
void (* transform_coords_to_gl) (CoglTexture *tex,
float *s,
float *t);
CoglTransformResult (* transform_quad_coords_to_gl) (CoglTexture *tex,
float *coords);
gboolean (* get_gl_texture) (CoglTexture *tex,
GLuint *out_gl_handle,
GLenum *out_gl_target);
void (* set_filters) (CoglTexture *tex,
GLenum min_filter,
GLenum mag_filter);
void (* pre_paint) (CoglTexture *tex, CoglTexturePrePaintFlags flags);
void (* ensure_non_quad_rendering) (CoglTexture *tex);
void (* set_wrap_mode_parameters) (CoglTexture *tex,
GLenum wrap_mode_s,
GLenum wrap_mode_t,
GLenum wrap_mode_p);
CoglPixelFormat (* get_format) (CoglTexture *tex);
GLenum (* get_gl_format) (CoglTexture *tex);
int (* get_width) (CoglTexture *tex);
int (* get_height) (CoglTexture *tex);
gboolean (* is_foreign) (CoglTexture *tex);
};
struct _CoglTexture
{
CoglObject _parent;
GList *framebuffers;
const CoglTextureVtable *vtable;
};
typedef enum _CoglTextureChangeFlags
{
/* Whenever the internals of a texture are changed such that the
* underlying GL textures that represent the CoglTexture change then
* we notify cogl-material.c via
* _cogl_pipeline_texture_pre_change_notify
*/
COGL_TEXTURE_CHANGE_GL_TEXTURES
} CoglTextureChangeFlags;
typedef struct _CoglTexturePixel CoglTexturePixel;
/* This is used by the texture backends to store the first pixel of
each GL texture. This is only used when glGenerateMipmap is not
available so that we can temporarily set GL_GENERATE_MIPMAP and
reupload a pixel */
struct _CoglTexturePixel
{
/* We need to store the format of the pixel because we store the
data in the source format which might end up being different for
each slice if a subregion is updated with a different format */
GLenum gl_format;
GLenum gl_type;
guint8 data[4];
};
void
_cogl_texture_init (CoglTexture *texture,
const CoglTextureVtable *vtable);
void
_cogl_texture_free (CoglTexture *texture);
/* This is used to register a type to the list of handle types that
will be considered a texture in cogl_is_texture() */
void
_cogl_texture_register_texture_type (GQuark type);
#define COGL_TEXTURE_DEFINE(TypeName, type_name) \
COGL_HANDLE_DEFINE_WITH_CODE \
(TypeName, type_name, \
_cogl_texture_register_texture_type (_cogl_handle_ \
## type_name ## _get_type ()))
#define COGL_TEXTURE_INTERNAL_DEFINE(TypeName, type_name) \
COGL_HANDLE_INTERNAL_DEFINE_WITH_CODE \
(TypeName, type_name, \
_cogl_texture_register_texture_type (_cogl_handle_ \
## type_name ## _get_type ()))
void
_cogl_texture_foreach_sub_texture_in_region (CoglTexture *texture,
float virtual_tx_1,
float virtual_ty_1,
float virtual_tx_2,
float virtual_ty_2,
CoglTextureSliceCallback callback,
void *user_data);
gboolean
_cogl_texture_can_hardware_repeat (CoglTexture *texture);
void
_cogl_texture_transform_coords_to_gl (CoglTexture *texture,
float *s,
float *t);
CoglTransformResult
_cogl_texture_transform_quad_coords_to_gl (CoglTexture *texture,
float *coords);
GLenum
_cogl_texture_get_gl_format (CoglTexture *texture);
void
_cogl_texture_set_wrap_mode_parameters (CoglTexture *texture,
GLenum wrap_mode_s,
GLenum wrap_mode_t,
GLenum wrap_mode_p);
void
_cogl_texture_set_filters (CoglTexture *texture,
GLenum min_filter,
GLenum mag_filter);
void
_cogl_texture_pre_paint (CoglTexture *texture, CoglTexturePrePaintFlags flags);
void
_cogl_texture_ensure_non_quad_rendering (CoglTexture *texture);
/* Utility function to determine which pixel format to use when
dst_format is COGL_PIXEL_FORMAT_ANY. If dst_format is not ANY then
it will just be returned directly */
CoglPixelFormat
_cogl_texture_determine_internal_format (CoglPixelFormat src_format,
CoglPixelFormat dst_format);
/* Utility function to help uploading a bitmap. If the bitmap needs
premult conversion then it will be copied and *copied_bitmap will
be set to TRUE. Otherwise dst_bmp will be set to a shallow copy of
src_bmp. The GLenums needed for uploading are returned */
CoglBitmap *
_cogl_texture_prepare_for_upload (CoglBitmap *src_bmp,
CoglPixelFormat dst_format,
CoglPixelFormat *dst_format_out,
GLenum *out_glintformat,
GLenum *out_glformat,
GLenum *out_gltype);
void
_cogl_texture_prep_gl_alignment_for_pixels_upload (int pixels_rowstride);
void
_cogl_texture_prep_gl_alignment_for_pixels_download (int pixels_rowstride);
/* Utility function for implementing manual repeating. Even texture
backends that always support hardware repeating need this because
when foreach_sub_texture_in_region is invoked Cogl will set the
wrap mode to GL_CLAMP_TO_EDGE so hardware repeating can't be
done */
void
_cogl_texture_iterate_manual_repeats (CoglTextureManualRepeatCallback callback,
float tx_1, float ty_1,
float tx_2, float ty_2,
void *user_data);
/* Utility function to use as a fallback for getting the data of any
texture via the framebuffer */
gboolean
_cogl_texture_draw_and_read (CoglTexture *texture,
CoglBitmap *target_bmp,
GLuint target_gl_format,
GLuint target_gl_type);
gboolean
_cogl_texture_is_foreign (CoglTexture *texture);
void
_cogl_texture_associate_framebuffer (CoglTexture *texture,
CoglFramebuffer *framebuffer);
const GList *
_cogl_texture_get_associated_framebuffers (CoglTexture *texture);
void
_cogl_texture_flush_journal_rendering (CoglTexture *texture);
#endif /* __COGL_TEXTURE_PRIVATE_H */