mutter/cogl/cogl-context-private.h
Robert Bragg 3ed8c8d0ba framebuffer: Add dither_enabled getter/setters
This adds a getter and setter for requesting dithering to be enabled.

Dithering is a hardware dependent technique to increase the visible
color resolution beyond what the underlying hardware supports by playing
tricks with the colors placed into the framebuffer to give the illusion
of other colors. (For example this can be compared to half-toning used
by some news papers to show varying levels of grey even though their may
only be black and white are available).

The results of enabling dithering are platform dependent and may have no
effect.

Signed-off-by: Neil Roberts <neil@linux.intel.com>
2011-07-13 19:06:19 +01:00

311 lines
10 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_CONTEXT_PRIVATE_H
#define __COGL_CONTEXT_PRIVATE_H
#include "cogl-internal.h"
#include "cogl-context.h"
#include "cogl-winsys-private.h"
#include "cogl-flags.h"
#ifdef COGL_HAS_XLIB_SUPPORT
#include "cogl-xlib-private.h"
#endif
#include "cogl-display-private.h"
#include "cogl-primitives.h"
#include "cogl-clip-stack.h"
#include "cogl-matrix-stack.h"
#include "cogl-pipeline-private.h"
#include "cogl-buffer-private.h"
#include "cogl-bitmask.h"
#include "cogl-atlas.h"
#include "cogl-texture-driver.h"
#include "cogl-pipeline-cache.h"
typedef struct
{
GLfloat v[3];
GLfloat t[2];
GLubyte c[4];
} CoglTextureGLVertex;
struct _CoglContext
{
CoglObject _parent;
CoglDisplay *display;
CoglDriver driver;
/* vtable for the texture driver functions */
const CoglTextureDriver *texture_driver;
/* Features cache */
CoglFeatureFlags feature_flags;
CoglPrivateFeatureFlags private_feature_flags;
CoglHandle default_pipeline;
CoglHandle default_layer_0;
CoglHandle default_layer_n;
CoglHandle dummy_layer_dependant;
/* Enable cache */
unsigned long enable_flags;
gboolean enable_backface_culling;
CoglFrontWinding flushed_front_winding;
/* A few handy matrix constants */
CoglMatrix identity_matrix;
CoglMatrix y_flip_matrix;
/* Client-side matrix stack or NULL if none */
CoglMatrixMode flushed_matrix_mode;
/* On GLES2 we need to track the matrices separately because the are
stored in GLSL uniforms rather than using the fixed function
API. We keep track of the matrix stack that Cogl is trying to
flush so we can flush it later after the program is generated. A
reference is taken on the stacks. */
CoglMatrixStack *flushed_modelview_stack;
CoglMatrixStack *flushed_projection_stack;
GArray *texture_units;
int active_texture_unit;
CoglPipelineFogState legacy_fog_state;
/* Pipelines */
CoglPipeline *opaque_color_pipeline; /* used for set_source_color */
CoglPipeline *blended_color_pipeline; /* used for set_source_color */
CoglPipeline *texture_pipeline; /* used for set_source_texture */
GString *codegen_header_buffer;
GString *codegen_source_buffer;
GList *source_stack;
int legacy_state_set;
CoglPipelineCache *pipeline_cache;
/* Textures */
CoglHandle default_gl_texture_2d_tex;
CoglHandle default_gl_texture_rect_tex;
/* Central list of all framebuffers so all journals can be flushed
* at any time. */
GList *framebuffers;
/* Global journal buffers */
GArray *journal_flush_attributes_array;
GArray *journal_clip_bounds;
GArray *polygon_vertices;
/* Some simple caching, to minimize state changes... */
CoglPipeline *current_pipeline;
unsigned long current_pipeline_changes_since_flush;
gboolean current_pipeline_skip_gl_color;
unsigned long current_pipeline_age;
GArray *pipeline0_nodes;
GArray *pipeline1_nodes;
/* Bitmask of attributes enabled. On GLES2 these are the vertex
attribute numbers and on regular GL these are only used for the
texture coordinate arrays */
CoglBitmask arrays_enabled;
/* These are temporary bitmasks that are used when disabling
texcoord arrays. They are here just to avoid allocating new ones
each time */
CoglBitmask arrays_to_change;
CoglBitmask temp_bitmask;
gboolean gl_blend_enable_cache;
gboolean depth_test_enabled_cache;
CoglDepthTestFunction depth_test_function_cache;
gboolean depth_writing_enabled_cache;
float depth_range_near_cache;
float depth_range_far_cache;
gboolean legacy_depth_test_enabled;
float point_size_cache;
CoglBuffer *current_buffer[COGL_BUFFER_BIND_TARGET_COUNT];
/* Framebuffers */
GSList *framebuffer_stack;
CoglHandle window_buffer;
gboolean dirty_bound_framebuffer;
gboolean dirty_gl_viewport;
/* Primitives */
CoglPath *current_path;
CoglPipeline *stencil_pipeline;
/* Pre-generated VBOs containing indices to generate GL_TRIANGLES
out of a vertex array of quads */
CoglHandle quad_buffer_indices_byte;
unsigned int quad_buffer_indices_len;
CoglHandle quad_buffer_indices;
CoglIndices *rectangle_byte_indices;
CoglIndices *rectangle_short_indices;
int rectangle_short_indices_len;
gboolean in_begin_gl_block;
CoglPipeline *texture_download_pipeline;
CoglPipeline *blit_texture_pipeline;
GSList *atlases;
GHookList atlas_reorganize_callbacks;
/* This debugging variable is used to pick a colour for visually
displaying the quad batches. It needs to be global so that it can
be reset by cogl_clear. It needs to be reset to increase the
chances of getting the same colour during an animation */
guint8 journal_rectangles_color;
/* Cached values for GL_MAX_TEXTURE_[IMAGE_]UNITS to avoid calling
glGetInteger too often */
GLint max_texture_units;
GLint max_texture_image_units;
GLint max_activateable_texture_units;
/* Fragment processing programs */
CoglHandle current_program;
CoglPipelineProgramType current_fragment_program_type;
CoglPipelineProgramType current_vertex_program_type;
GLuint current_gl_program;
gboolean current_gl_dither_enabled;
/* List of types that will be considered a subclass of CoglTexture in
cogl_is_texture */
GSList *texture_types;
/* List of types that will be considered a subclass of CoglBuffer in
cogl_is_buffer */
GSList *buffer_types;
/* Clipping */
/* TRUE if we have a valid clipping stack flushed. In that case
current_clip_stack will describe what the current state is. If
this is FALSE then the current clip stack is completely unknown
so it will need to be reflushed. In that case current_clip_stack
doesn't need to be a valid pointer. We can't just use NULL in
current_clip_stack to mark a dirty state because NULL is a valid
stack (meaning no clipping) */
gboolean current_clip_stack_valid;
/* The clip state that was flushed. This isn't intended to be used
as a stack to push and pop new entries. Instead the current stack
that the user wants is part of the framebuffer state. This is
just used to record the flush state so we can avoid flushing the
same state multiple times. When the clip state is flushed this
will hold a reference */
CoglClipStack *current_clip_stack;
/* Whether the stencil buffer was used as part of the current clip
state. If TRUE then any further use of the stencil buffer (such
as for drawing paths) would need to be merged with the existing
stencil buffer */
gboolean current_clip_stack_uses_stencil;
/* This is used as a temporary buffer to fill a CoglBuffer when
cogl_buffer_map fails and we only want to map to fill it with new
data */
GByteArray *buffer_map_fallback_array;
gboolean buffer_map_fallback_in_use;
CoglWinsysRectangleState rectangle_state;
/* FIXME: remove these when we remove the last xlib based clutter
* backend. they should be tracked as part of the renderer but e.g.
* the eglx backend doesn't yet have a corresponding Cogl winsys
* and so we wont have a renderer in that case. */
#ifdef COGL_HAS_XLIB_SUPPORT
int damage_base;
/* List of callback functions that will be given every Xlib event */
GSList *event_filters;
/* Current top of the XError trap state stack. The actual memory for
these is expected to be allocated on the stack by the caller */
CoglXlibTrapState *trap_state;
#endif
unsigned int winsys_features
[COGL_FLAGS_N_INTS_FOR_SIZE (COGL_WINSYS_FEATURE_N_FEATURES)];
void *winsys;
/* This defines a list of function pointers that Cogl uses from
either GL or GLES. All functions are accessed indirectly through
these pointers rather than linking to them directly */
#ifndef APIENTRY
#define APIENTRY
#endif
#define COGL_EXT_BEGIN(name, \
min_gl_major, min_gl_minor, \
gles_availability, \
extension_suffixes, extension_names)
#define COGL_EXT_FUNCTION(ret, name, args) \
ret (APIENTRY * name) args;
#define COGL_EXT_END()
#include "cogl-ext-functions.h"
#undef COGL_EXT_BEGIN
#undef COGL_EXT_FUNCTION
#undef COGL_EXT_END
};
CoglContext *
_cogl_context_get_default ();
const CoglWinsysVtable *
_cogl_context_get_winsys (CoglContext *context);
/* Check whether the current GL context is supported by Cogl */
gboolean
_cogl_context_check_gl_version (CoglContext *context,
GError **error);
/* Query the GL extensions and lookup the corresponding function
* pointers. Theoretically the list of extensions can change for
* different GL contexts so it is the winsys backend's responsiblity
* to know when to re-query the GL extensions. */
void
_cogl_context_update_features (CoglContext *context);
/* Obtains the context and returns retval if NULL */
#define _COGL_GET_CONTEXT(ctxvar, retval) \
CoglContext *ctxvar = _cogl_context_get_default (); \
if (ctxvar == NULL) return retval;
#define NO_RETVAL
#endif /* __COGL_CONTEXT_PRIVATE_H */