mutter/cogl/cogl-context.c
Robert Bragg 010d16f647 Adds initial GLES2 integration support
This makes it possible to integrate existing GLES2 code with
applications using Cogl as the rendering api.

Currently all GLES2 usage is handled with separate GLES2 contexts to
ensure that GLES2 api usage doesn't interfere with Cogl's own use of
OpenGL[ES]. The api has been designed though so we can provide tighter
integration later.

The api would allow us to support GLES2 virtualized on top of an
OpenGL/GLX driver as well as GLES2 virtualized on the core rendering api
of Cogl itself. Virtualizing the GLES2 support on Cogl will allow us to
take advantage of Cogl debugging facilities as well as let us optimize
the cost of allocating multiple GLES2 contexts and switching between
them which can both be very expensive with many drivers.

As as a side effect of this patch Cogl can also now be used as a
portable window system binding API for GLES2 as an alternative to EGL.

Parts of this patch are based on work done by Tomeu Vizoso
<tomeu.vizoso@collabora.com> who did the first iteration of adding GLES2
API support to Cogl so that WebGL support could be added to
webkit-clutter.

This patch adds a very minimal cogl-gles2-context example that shows how
to create a gles2 context, clear the screen to a random color and also
draw a triangle with the cogl api.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit 4bb6eff3dbd50d8fef7d6bdbed55c5aaa70036a8)
2012-08-06 14:27:42 +01:00

620 lines
21 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/>.
*
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl-object.h"
#include "cogl-internal.h"
#include "cogl-private.h"
#include "cogl-winsys-private.h"
#include "winsys/cogl-winsys-stub-private.h"
#include "cogl-profile.h"
#include "cogl-util.h"
#include "cogl-context-private.h"
#include "cogl-display-private.h"
#include "cogl-renderer-private.h"
#include "cogl-journal-private.h"
#include "cogl-texture-private.h"
#include "cogl-texture-2d-private.h"
#include "cogl-texture-3d-private.h"
#include "cogl-texture-rectangle-private.h"
#include "cogl-pipeline-private.h"
#include "cogl-pipeline-opengl-private.h"
#include "cogl-framebuffer-private.h"
#include "cogl-onscreen-private.h"
#include "cogl2-path.h"
#include "cogl-attribute-private.h"
#include "cogl1-context.h"
#include "cogl-gpu-info-private.h"
#include <string.h>
#ifdef HAVE_COGL_GL
#include "cogl-pipeline-fragend-arbfp-private.h"
#endif
/* This isn't defined in the GLES headers */
#ifndef GL_POINT_SPRITE
#define GL_POINT_SPRITE 0x8861
#endif
#ifdef HAVE_COGL_GL
extern const CoglTextureDriver _cogl_texture_driver_gl;
extern const CoglDriverVtable _cogl_driver_gl;
#endif
#if defined (HAVE_COGL_GLES) || defined (HAVE_COGL_GLES2)
extern const CoglTextureDriver _cogl_texture_driver_gles;
extern const CoglDriverVtable _cogl_driver_gles;
#endif
static void _cogl_context_free (CoglContext *context);
COGL_OBJECT_DEFINE (Context, context);
extern void
_cogl_create_context_driver (CoglContext *context);
static CoglContext *_context = NULL;
static void
_cogl_init_feature_overrides (CoglContext *ctx)
{
if (G_UNLIKELY (COGL_DEBUG_ENABLED (COGL_DEBUG_DISABLE_VBOS)))
ctx->private_feature_flags &= ~COGL_PRIVATE_FEATURE_VBOS;
if (G_UNLIKELY (COGL_DEBUG_ENABLED (COGL_DEBUG_DISABLE_PBOS)))
ctx->private_feature_flags &= ~COGL_PRIVATE_FEATURE_PBOS;
if (G_UNLIKELY (COGL_DEBUG_ENABLED (COGL_DEBUG_DISABLE_ARBFP)))
{
ctx->feature_flags &= ~COGL_FEATURE_SHADERS_ARBFP;
COGL_FLAGS_SET (ctx->features, COGL_FEATURE_ID_ARBFP, FALSE);
}
if (G_UNLIKELY (COGL_DEBUG_ENABLED (COGL_DEBUG_DISABLE_GLSL)))
{
ctx->feature_flags &= ~COGL_FEATURE_SHADERS_GLSL;
COGL_FLAGS_SET (ctx->features, COGL_FEATURE_ID_GLSL, FALSE);
}
if (G_UNLIKELY (COGL_DEBUG_ENABLED (COGL_DEBUG_DISABLE_NPOT_TEXTURES)))
{
ctx->feature_flags &= ~(COGL_FEATURE_TEXTURE_NPOT |
COGL_FEATURE_TEXTURE_NPOT_BASIC |
COGL_FEATURE_TEXTURE_NPOT_MIPMAP |
COGL_FEATURE_TEXTURE_NPOT_REPEAT);
COGL_FLAGS_SET (ctx->features, COGL_FEATURE_ID_TEXTURE_NPOT, FALSE);
COGL_FLAGS_SET (ctx->features,
COGL_FEATURE_ID_TEXTURE_NPOT_BASIC, FALSE);
COGL_FLAGS_SET (ctx->features,
COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP, FALSE);
COGL_FLAGS_SET (ctx->features,
COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT, FALSE);
}
}
const CoglWinsysVtable *
_cogl_context_get_winsys (CoglContext *context)
{
return context->display->renderer->winsys_vtable;
}
/* For reference: There was some deliberation over whether to have a
* constructor that could throw an exception but looking at standard
* practices with several high level OO languages including python, C++,
* C# Java and Ruby they all support exceptions in constructors and the
* general consensus appears to be that throwing an exception is neater
* than successfully constructing with an internal error status that
* would then have to be explicitly checked via some form of ::is_ok()
* method.
*/
CoglContext *
cogl_context_new (CoglDisplay *display,
GError **error)
{
CoglContext *context;
GLubyte default_texture_data[] = { 0xff, 0xff, 0xff, 0x0 };
CoglBitmap *default_texture_bitmap;
const CoglWinsysVtable *winsys;
int i;
_cogl_init ();
#ifdef COGL_ENABLE_PROFILE
/* We need to be absolutely sure that uprof has been initialized
* before calling _cogl_uprof_init. uprof_init (NULL, NULL)
* will be a NOP if it has been initialized but it will also
* mean subsequent parsing of the UProf GOptionGroup will have no
* affect.
*
* Sadly GOptionGroup based library initialization is extremely
* fragile by design because GOptionGroups have no notion of
* dependencies and so the order things are initialized isn't
* currently under tight control.
*/
uprof_init (NULL, NULL);
_cogl_uprof_init ();
#endif
/* Allocate context memory */
context = g_malloc0 (sizeof (CoglContext));
/* Convert the context into an object immediately in case any of the
code below wants to verify that the context pointer is a valid
object */
_cogl_context_object_new (context);
/* XXX: Gross hack!
* Currently everything in Cogl just assumes there is a default
* context which it can access via _COGL_GET_CONTEXT() including
* code used to construct a CoglContext. Until all of that code
* has been updated to take an explicit context argument we have
* to immediately make our pointer the default context.
*/
_context = context;
/* Init default values */
memset (context->features, 0, sizeof (context->features));
context->feature_flags = 0;
context->private_feature_flags = 0;
context->texture_types = NULL;
context->buffer_types = NULL;
context->rectangle_state = COGL_WINSYS_RECTANGLE_STATE_UNKNOWN;
memset (context->winsys_features, 0, sizeof (context->winsys_features));
if (!display)
{
CoglRenderer *renderer = cogl_renderer_new ();
if (!cogl_renderer_connect (renderer, error))
{
g_free (context);
return NULL;
}
display = cogl_display_new (renderer, NULL);
}
else
cogl_object_ref (display);
if (!cogl_display_setup (display, error))
{
cogl_object_unref (display);
g_free (context);
return NULL;
}
context->display = display;
/* This is duplicated data, but it's much more convenient to have
the driver attached to the context and the value is accessed a
lot throughout Cogl */
context->driver = display->renderer->driver;
switch (context->driver)
{
#ifdef HAVE_COGL_GL
case COGL_DRIVER_GL:
context->driver_vtable = &_cogl_driver_gl;
context->texture_driver = &_cogl_texture_driver_gl;
break;
#endif
#if defined (HAVE_COGL_GLES) || defined (HAVE_COGL_GLES2)
case COGL_DRIVER_GLES1:
case COGL_DRIVER_GLES2:
context->driver_vtable = &_cogl_driver_gles;
context->texture_driver = &_cogl_texture_driver_gles;
break;
#endif
default:
g_assert_not_reached ();
}
winsys = _cogl_context_get_winsys (context);
if (!winsys->context_init (context, error))
{
cogl_object_unref (display);
g_free (context);
return NULL;
}
context->attribute_name_states_hash =
g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
context->attribute_name_index_map = NULL;
context->n_attribute_names = 0;
/* The "cogl_color_in" attribute needs a deterministic name_index
* so we make sure it's the first attribute name we register */
_cogl_attribute_register_attribute_name (context, "cogl_color_in");
context->uniform_names =
g_ptr_array_new_with_free_func ((GDestroyNotify) g_free);
context->uniform_name_hash = g_hash_table_new (g_str_hash, g_str_equal);
context->n_uniform_names = 0;
/* Initialise the driver specific state */
_cogl_init_feature_overrides (context);
_context->sampler_cache = _cogl_sampler_cache_new (_context);
_cogl_pipeline_init_default_pipeline ();
_cogl_pipeline_init_default_layers ();
_cogl_pipeline_init_state_hash_functions ();
_cogl_pipeline_init_layer_state_hash_functions ();
context->current_clip_stack_valid = FALSE;
context->current_clip_stack = NULL;
context->legacy_backface_culling_enabled = FALSE;
cogl_matrix_init_identity (&context->identity_matrix);
cogl_matrix_init_identity (&context->y_flip_matrix);
cogl_matrix_scale (&context->y_flip_matrix, 1, -1, 1);
context->flushed_matrix_mode = COGL_MATRIX_MODELVIEW;
context->texture_units =
g_array_new (FALSE, FALSE, sizeof (CoglTextureUnit));
/* See cogl-pipeline.c for more details about why we leave texture unit 1
* active by default... */
context->active_texture_unit = 1;
GE (context, glActiveTexture (GL_TEXTURE1));
context->legacy_fog_state.enabled = FALSE;
context->opaque_color_pipeline = cogl_pipeline_new (context);
context->blended_color_pipeline = cogl_pipeline_new (context);
context->texture_pipeline = cogl_pipeline_new (context);
context->codegen_header_buffer = g_string_new ("");
context->codegen_source_buffer = g_string_new ("");
context->source_stack = NULL;
context->legacy_state_set = 0;
context->default_gl_texture_2d_tex = NULL;
context->default_gl_texture_3d_tex = NULL;
context->default_gl_texture_rect_tex = NULL;
context->framebuffers = NULL;
context->current_draw_buffer = NULL;
context->current_read_buffer = NULL;
context->current_draw_buffer_state_flushed = 0;
context->current_draw_buffer_changes = COGL_FRAMEBUFFER_STATE_ALL;
g_queue_init (&context->gles2_context_stack);
context->journal_flush_attributes_array =
g_array_new (TRUE, FALSE, sizeof (CoglAttribute *));
context->journal_clip_bounds = NULL;
context->polygon_vertices = g_array_new (FALSE, FALSE, sizeof (float));
context->current_pipeline = NULL;
context->current_pipeline_changes_since_flush = 0;
context->current_pipeline_skip_gl_color = FALSE;
_cogl_bitmask_init (&context->enabled_builtin_attributes);
_cogl_bitmask_init (&context->enable_builtin_attributes_tmp);
_cogl_bitmask_init (&context->enabled_texcoord_attributes);
_cogl_bitmask_init (&context->enable_texcoord_attributes_tmp);
_cogl_bitmask_init (&context->enabled_custom_attributes);
_cogl_bitmask_init (&context->enable_custom_attributes_tmp);
_cogl_bitmask_init (&context->changed_bits_tmp);
context->max_texture_units = -1;
context->max_activateable_texture_units = -1;
context->current_fragment_program_type = COGL_PIPELINE_PROGRAM_TYPE_FIXED;
context->current_vertex_program_type = COGL_PIPELINE_PROGRAM_TYPE_FIXED;
context->current_gl_program = 0;
context->current_gl_dither_enabled = TRUE;
context->current_gl_color_mask = COGL_COLOR_MASK_ALL;
context->gl_blend_enable_cache = FALSE;
context->depth_test_enabled_cache = FALSE;
context->depth_test_function_cache = COGL_DEPTH_TEST_FUNCTION_LESS;
context->depth_writing_enabled_cache = TRUE;
context->depth_range_near_cache = 0;
context->depth_range_far_cache = 1;
context->legacy_depth_test_enabled = FALSE;
context->pipeline_cache = cogl_pipeline_cache_new ();
for (i = 0; i < COGL_BUFFER_BIND_TARGET_COUNT; i++)
context->current_buffer[i] = NULL;
context->window_buffer = NULL;
context->framebuffer_stack = _cogl_create_framebuffer_stack ();
/* XXX: In this case the Clutter backend is still responsible for
* the OpenGL binding API and for creating onscreen framebuffers and
* so we have to add a dummy framebuffer to represent the backend
* owned window... */
if (_cogl_context_get_winsys (context) == _cogl_winsys_stub_get_vtable ())
{
CoglOnscreen *window = _cogl_onscreen_new ();
cogl_set_framebuffer (COGL_FRAMEBUFFER (window));
cogl_object_unref (COGL_FRAMEBUFFER (window));
}
context->current_path = cogl2_path_new ();
context->stencil_pipeline = cogl_pipeline_new (context);
context->in_begin_gl_block = FALSE;
context->quad_buffer_indices_byte = NULL;
context->quad_buffer_indices = NULL;
context->quad_buffer_indices_len = 0;
context->rectangle_byte_indices = NULL;
context->rectangle_short_indices = NULL;
context->rectangle_short_indices_len = 0;
context->texture_download_pipeline = NULL;
context->blit_texture_pipeline = NULL;
#if defined (HAVE_COGL_GL) || defined (HAVE_COGL_GLES)
if (context->driver != COGL_DRIVER_GLES2)
/* The default for GL_ALPHA_TEST is to always pass which is equivalent to
* the test being disabled therefore we assume that for all drivers there
* will be no performance impact if we always leave the test enabled which
* makes things a bit simpler for us. Under GLES2 the alpha test is
* implemented in the fragment shader so there is no enable for it
*/
GE (context, glEnable (GL_ALPHA_TEST));
#endif
_context->current_modelview_entry = NULL;
_context->current_projection_entry = NULL;
_cogl_matrix_entry_identity_init (&_context->identity_entry);
_cogl_matrix_entry_cache_init (&_context->builtin_flushed_projection);
_cogl_matrix_entry_cache_init (&_context->builtin_flushed_modelview);
default_texture_bitmap =
cogl_bitmap_new_for_data (_context,
1, 1, /* width/height */
COGL_PIXEL_FORMAT_RGBA_8888_PRE,
4, /* rowstride */
default_texture_data);
/* Create default textures used for fall backs */
context->default_gl_texture_2d_tex =
cogl_texture_2d_new_from_bitmap (default_texture_bitmap,
/* internal format */
COGL_PIXEL_FORMAT_RGBA_8888_PRE,
NULL);
/* If 3D or rectangle textures aren't supported then these should
just silently return NULL */
context->default_gl_texture_3d_tex =
cogl_texture_3d_new_from_bitmap (default_texture_bitmap,
1, /* height */
1, /* depth */
COGL_PIXEL_FORMAT_RGBA_8888_PRE,
NULL);
context->default_gl_texture_rect_tex =
cogl_texture_rectangle_new_from_bitmap (default_texture_bitmap,
COGL_PIXEL_FORMAT_RGBA_8888_PRE,
NULL);
cogl_object_unref (default_texture_bitmap);
cogl_push_source (context->opaque_color_pipeline);
context->atlases = NULL;
g_hook_list_init (&context->atlas_reorganize_callbacks, sizeof (GHook));
_context->buffer_map_fallback_array = g_byte_array_new ();
_context->buffer_map_fallback_in_use = FALSE;
/* As far as I can tell, GL_POINT_SPRITE doesn't have any effect
unless GL_COORD_REPLACE is enabled for an individual
layer. Therefore it seems like it should be ok to just leave it
enabled all the time instead of having to have a set property on
each pipeline to track whether any layers have point sprite
coords enabled. We don't need to do this for GLES2 because point
sprites are handled using a builtin varying in the shader. */
if (_context->driver != COGL_DRIVER_GLES2 &&
cogl_has_feature (context, COGL_FEATURE_ID_POINT_SPRITE))
GE (context, glEnable (GL_POINT_SPRITE));
return context;
}
static void
_cogl_context_free (CoglContext *context)
{
const CoglWinsysVtable *winsys = _cogl_context_get_winsys (context);
winsys->context_deinit (context);
_cogl_free_framebuffer_stack (context->framebuffer_stack);
if (context->current_path)
cogl_handle_unref (context->current_path);
if (context->default_gl_texture_2d_tex)
cogl_object_unref (context->default_gl_texture_2d_tex);
if (context->default_gl_texture_3d_tex)
cogl_object_unref (context->default_gl_texture_3d_tex);
if (context->default_gl_texture_rect_tex)
cogl_object_unref (context->default_gl_texture_rect_tex);
if (context->opaque_color_pipeline)
cogl_object_unref (context->opaque_color_pipeline);
if (context->blended_color_pipeline)
cogl_object_unref (context->blended_color_pipeline);
if (context->texture_pipeline)
cogl_object_unref (context->texture_pipeline);
if (context->blit_texture_pipeline)
cogl_object_unref (context->blit_texture_pipeline);
g_warn_if_fail (context->gles2_context_stack.length == 0);
if (context->journal_flush_attributes_array)
g_array_free (context->journal_flush_attributes_array, TRUE);
if (context->journal_clip_bounds)
g_array_free (context->journal_clip_bounds, TRUE);
if (context->polygon_vertices)
g_array_free (context->polygon_vertices, TRUE);
if (context->quad_buffer_indices_byte)
cogl_object_unref (context->quad_buffer_indices_byte);
if (context->quad_buffer_indices)
cogl_object_unref (context->quad_buffer_indices);
if (context->rectangle_byte_indices)
cogl_object_unref (context->rectangle_byte_indices);
if (context->rectangle_short_indices)
cogl_object_unref (context->rectangle_short_indices);
if (context->default_pipeline)
cogl_object_unref (context->default_pipeline);
if (context->dummy_layer_dependant)
cogl_object_unref (context->dummy_layer_dependant);
if (context->default_layer_n)
cogl_object_unref (context->default_layer_n);
if (context->default_layer_0)
cogl_object_unref (context->default_layer_0);
if (context->current_clip_stack_valid)
_cogl_clip_stack_unref (context->current_clip_stack);
g_slist_free (context->atlases);
g_hook_list_clear (&context->atlas_reorganize_callbacks);
_cogl_bitmask_destroy (&context->enabled_builtin_attributes);
_cogl_bitmask_destroy (&context->enable_builtin_attributes_tmp);
_cogl_bitmask_destroy (&context->enabled_texcoord_attributes);
_cogl_bitmask_destroy (&context->enable_texcoord_attributes_tmp);
_cogl_bitmask_destroy (&context->enabled_custom_attributes);
_cogl_bitmask_destroy (&context->enable_custom_attributes_tmp);
_cogl_bitmask_destroy (&context->changed_bits_tmp);
g_slist_free (context->texture_types);
g_slist_free (context->buffer_types);
if (_context->current_modelview_entry)
_cogl_matrix_entry_unref (_context->current_modelview_entry);
if (_context->current_projection_entry)
_cogl_matrix_entry_unref (_context->current_projection_entry);
_cogl_matrix_entry_cache_destroy (&context->builtin_flushed_projection);
_cogl_matrix_entry_cache_destroy (&context->builtin_flushed_modelview);
cogl_pipeline_cache_free (context->pipeline_cache);
_cogl_sampler_cache_free (context->sampler_cache);
_cogl_destroy_texture_units ();
g_ptr_array_free (context->uniform_names, TRUE);
g_hash_table_destroy (context->uniform_name_hash);
g_hash_table_destroy (context->attribute_name_states_hash);
g_array_free (context->attribute_name_index_map, TRUE);
g_byte_array_free (context->buffer_map_fallback_array, TRUE);
cogl_object_unref (context->display);
g_free (context);
}
CoglContext *
_cogl_context_get_default (void)
{
GError *error = NULL;
/* Create if doesn't exist yet */
if (_context == NULL)
{
_context = cogl_context_new (NULL, &error);
if (!_context)
{
g_warning ("Failed to create default context: %s",
error->message);
g_error_free (error);
}
}
return _context;
}
CoglDisplay *
cogl_context_get_display (CoglContext *context)
{
return context->display;
}
#ifdef COGL_HAS_EGL_SUPPORT
EGLDisplay
cogl_egl_context_get_egl_display (CoglContext *context)
{
const CoglWinsysVtable *winsys = _cogl_context_get_winsys (context);
/* This should only be called for EGL contexts */
_COGL_RETURN_VAL_IF_FAIL (winsys->context_egl_get_egl_display != NULL, NULL);
return winsys->context_egl_get_egl_display (context);
}
#endif
CoglBool
_cogl_context_update_features (CoglContext *context,
GError **error)
{
return context->driver_vtable->update_features (context, error);
}
void
_cogl_context_set_current_projection_entry (CoglContext *context,
CoglMatrixEntry *entry)
{
_cogl_matrix_entry_ref (entry);
if (context->current_projection_entry)
_cogl_matrix_entry_unref (context->current_projection_entry);
context->current_projection_entry = entry;
}
void
_cogl_context_set_current_modelview_entry (CoglContext *context,
CoglMatrixEntry *entry)
{
_cogl_matrix_entry_ref (entry);
if (context->current_modelview_entry)
_cogl_matrix_entry_unref (context->current_modelview_entry);
context->current_modelview_entry = entry;
}