mutter/cogl/cogl.c
Neil Roberts 185630085c Add -Wmissing-declarations to maintainer flags and fix problems
This option to GCC makes it give a warning whenever a global function
is defined without a declaration. This should catch cases were we've
defined a function but forgot to put it in a header. In that case it
is either only used within one file so we should make it static or we
should declare it in a header.

The following changes where made to fix problems:

• Some functions were made static

• cogl-path.h (the one containing the 1.0 API) was split into two
  files, one defining the functions and one defining the enums so that
  cogl-path.c can include the enum and function declarations from the
  2.0 API as well as the function declarations from the 1.0 API.

• cogl2-clip-state has been removed. This only had one experimental
  function called cogl_clip_push_from_path but as this is unstable we
  might as well remove it favour of the equivalent cogl_framebuffer_*
  API.

• The GLX, SDL and WGL winsys's now have a private header to define
  their get_vtable function instead of directly declaring in the C
  file where it is called.

• All places that were calling COGL_OBJECT_DEFINE need to have the
  cogl_is_whatever function declared so these have been added either
  as a public function or in a private header.

• Some files that were not including the header containing their
  function declarations have been fixed to do so.

• Any unused error quark functions have been removed. If we later want
  them we should add them back one by one and add a declaration for
  them in a header.

• _cogl_is_framebuffer has been renamed to cogl_is_framebuffer and
  made a public function with a declaration in cogl-framebuffer.h

• Similarly for CoglOnscreen.

• cogl_vdraw_indexed_attributes is called
  cogl_framebuffer_vdraw_indexed_attributes in the header. The
  definition has been changed to match the header.

• cogl_index_buffer_allocate has been removed. This had no declaration
  and I'm not sure what it's supposed to do.

• CoglJournal has been changed to use the internal CoglObject macro so
  that it won't define an exported cogl_is_journal symbol.

• The _cogl_blah_pointer_from_handle functions have been removed.
  CoglHandle isn't used much anymore anyway and in the few places
  where it is used I think it's safe to just use the implicit cast
  from void* to the right type.

• The test-utils.h header for the conformance tests explicitly
  disables the -Wmissing-declaration option using a pragma because all
  of the tests declare their main function without a header. Any
  mistakes relating to missing declarations aren't really important
  for the tests.

• cogl_quaternion_init_from_quaternion and init_from_matrix have been
  given declarations in cogl-quaternion.h

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-06 18:45:44 +00:00

864 lines
21 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2007,2008,2009,2010 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 <string.h>
#include <math.h>
#include <stdlib.h>
#include <glib/gi18n-lib.h>
#include "cogl-debug.h"
#include "cogl-internal.h"
#include "cogl-util.h"
#include "cogl-context-private.h"
#include "cogl-pipeline-private.h"
#include "cogl-pipeline-opengl-private.h"
#include "cogl-winsys-private.h"
#include "cogl-framebuffer-private.h"
#include "cogl-matrix-private.h"
#include "cogl-journal-private.h"
#include "cogl-bitmap-private.h"
#include "cogl-texture-private.h"
#include "cogl-texture-driver.h"
#include "cogl-attribute-private.h"
#include "cogl-framebuffer-private.h"
#include "cogl-renderer-private.h"
#include "cogl-config-private.h"
#include "cogl-private.h"
#include "cogl1-context.h"
#include "cogl-offscreen.h"
#ifndef GL_PACK_INVERT_MESA
#define GL_PACK_INVERT_MESA 0x8758
#endif
#ifdef COGL_GL_DEBUG
/* GL error to string conversion */
static const struct {
GLuint error_code;
const char *error_string;
} gl_errors[] = {
{ GL_NO_ERROR, "No error" },
{ GL_INVALID_ENUM, "Invalid enumeration value" },
{ GL_INVALID_VALUE, "Invalid value" },
{ GL_INVALID_OPERATION, "Invalid operation" },
#ifdef HAVE_COGL_GL
{ GL_STACK_OVERFLOW, "Stack overflow" },
{ GL_STACK_UNDERFLOW, "Stack underflow" },
#endif
{ GL_OUT_OF_MEMORY, "Out of memory" },
#ifdef GL_INVALID_FRAMEBUFFER_OPERATION_EXT
{ GL_INVALID_FRAMEBUFFER_OPERATION_EXT, "Invalid framebuffer operation" }
#endif
};
static const unsigned int n_gl_errors = G_N_ELEMENTS (gl_errors);
const char *
cogl_gl_error_to_string (GLenum error_code)
{
int i;
for (i = 0; i < n_gl_errors; i++)
{
if (gl_errors[i].error_code == error_code)
return gl_errors[i].error_string;
}
return "Unknown GL error";
}
#endif /* COGL_GL_DEBUG */
CoglFuncPtr
cogl_get_proc_address (const char* name)
{
_COGL_GET_CONTEXT (ctx, NULL);
return _cogl_renderer_get_proc_address (ctx->display->renderer, name);
}
gboolean
_cogl_check_extension (const char *name, const gchar *ext)
{
char *end;
int name_len, n;
if (name == NULL || ext == NULL)
return FALSE;
end = (char*)(ext + strlen(ext));
name_len = strlen(name);
while (ext < end)
{
n = strcspn(ext, " ");
if ((name_len == n) && (!strncmp(name, ext, n)))
return TRUE;
ext += (n + 1);
}
return FALSE;
}
/* XXX: This has been deprecated as public API */
gboolean
cogl_check_extension (const char *name, const char *ext)
{
return _cogl_check_extension (name, ext);
}
/* XXX: it's expected that we'll deprecated this with
* cogl_framebuffer_clear at some point. */
void
cogl_clear (const CoglColor *color, unsigned long buffers)
{
cogl_framebuffer_clear (cogl_get_draw_framebuffer (), buffers, color);
}
/* XXX: This API has been deprecated */
void
cogl_set_depth_test_enabled (gboolean setting)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->legacy_depth_test_enabled == setting)
return;
ctx->legacy_depth_test_enabled = setting;
if (ctx->legacy_depth_test_enabled)
ctx->legacy_state_set++;
else
ctx->legacy_state_set--;
}
/* XXX: This API has been deprecated */
gboolean
cogl_get_depth_test_enabled (void)
{
_COGL_GET_CONTEXT (ctx, FALSE);
return ctx->legacy_depth_test_enabled;
}
void
cogl_set_backface_culling_enabled (gboolean setting)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->legacy_backface_culling_enabled == setting)
return;
ctx->legacy_backface_culling_enabled = setting;
if (ctx->legacy_backface_culling_enabled)
ctx->legacy_state_set++;
else
ctx->legacy_state_set--;
}
gboolean
cogl_get_backface_culling_enabled (void)
{
_COGL_GET_CONTEXT (ctx, FALSE);
return ctx->legacy_backface_culling_enabled;
}
void
cogl_set_source_color (const CoglColor *color)
{
CoglPipeline *pipeline;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (cogl_color_get_alpha_byte (color) == 0xff)
{
cogl_pipeline_set_color (ctx->opaque_color_pipeline, color);
pipeline = ctx->opaque_color_pipeline;
}
else
{
CoglColor premultiplied = *color;
cogl_color_premultiply (&premultiplied);
cogl_pipeline_set_color (ctx->blended_color_pipeline, &premultiplied);
pipeline = ctx->blended_color_pipeline;
}
cogl_set_source (pipeline);
}
void
cogl_set_viewport (int x,
int y,
int width,
int height)
{
CoglFramebuffer *framebuffer;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
framebuffer = cogl_get_draw_framebuffer ();
cogl_framebuffer_set_viewport (framebuffer,
x,
y,
width,
height);
}
/* XXX: This should be deprecated, and we should expose a way to also
* specify an x and y viewport offset */
void
cogl_viewport (unsigned int width,
unsigned int height)
{
cogl_set_viewport (0, 0, width, height);
}
CoglFeatureFlags
cogl_get_features (void)
{
_COGL_GET_CONTEXT (ctx, 0);
return ctx->feature_flags;
}
gboolean
cogl_features_available (CoglFeatureFlags features)
{
_COGL_GET_CONTEXT (ctx, 0);
return (ctx->feature_flags & features) == features;
}
gboolean
cogl_has_feature (CoglContext *ctx, CoglFeatureID feature)
{
return COGL_FLAGS_GET (ctx->features, feature);
}
gboolean
cogl_has_features (CoglContext *ctx, ...)
{
va_list args;
CoglFeatureID feature;
va_start (args, ctx);
while ((feature = va_arg (args, CoglFeatureID)))
if (!cogl_has_feature (ctx, feature))
return FALSE;
va_end (args);
return TRUE;
}
void
cogl_foreach_feature (CoglContext *ctx,
CoglFeatureCallback callback,
void *user_data)
{
int i;
for (i = 0; i < _COGL_N_FEATURE_IDS; i++)
if (COGL_FLAGS_GET (ctx->features, i))
callback (i, user_data);
}
/* XXX: This function should either be replaced with one returning
* integers, or removed/deprecated and make the
* _cogl_framebuffer_get_viewport* functions public.
*/
void
cogl_get_viewport (float viewport[4])
{
CoglFramebuffer *framebuffer;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
framebuffer = cogl_get_draw_framebuffer ();
cogl_framebuffer_get_viewport4fv (framebuffer, viewport);
}
void
cogl_get_bitmasks (int *red,
int *green,
int *blue,
int *alpha)
{
CoglFramebuffer *framebuffer;
framebuffer = cogl_get_draw_framebuffer ();
if (red)
*red = cogl_framebuffer_get_red_bits (framebuffer);
if (green)
*green = cogl_framebuffer_get_green_bits (framebuffer);
if (blue)
*blue = cogl_framebuffer_get_blue_bits (framebuffer);
if (alpha)
*alpha = cogl_framebuffer_get_alpha_bits (framebuffer);
}
void
cogl_set_fog (const CoglColor *fog_color,
CoglFogMode mode,
float density,
float z_near,
float z_far)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->legacy_fog_state.enabled == FALSE)
ctx->legacy_state_set++;
ctx->legacy_fog_state.enabled = TRUE;
ctx->legacy_fog_state.color = *fog_color;
ctx->legacy_fog_state.mode = mode;
ctx->legacy_fog_state.density = density;
ctx->legacy_fog_state.z_near = z_near;
ctx->legacy_fog_state.z_far = z_far;
}
void
cogl_disable_fog (void)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->legacy_fog_state.enabled == TRUE)
ctx->legacy_state_set--;
ctx->legacy_fog_state.enabled = FALSE;
}
void
cogl_flush (void)
{
GList *l;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
for (l = ctx->framebuffers; l; l = l->next)
_cogl_framebuffer_flush_journal (l->data);
}
void
cogl_read_pixels (int x,
int y,
int width,
int height,
CoglReadPixelsFlags source,
CoglPixelFormat format,
guint8 *pixels)
{
int bpp = _cogl_pixel_format_get_bytes_per_pixel (format);
CoglBitmap *bitmap;
bitmap = _cogl_bitmap_new_from_data (pixels,
format,
width, height,
bpp * width, /* rowstride */
NULL, /* destroy_fn */
NULL /* destroy_fn_data */);
cogl_framebuffer_read_pixels_into_bitmap (_cogl_get_read_framebuffer (),
x, y,
source,
bitmap);
cogl_object_unref (bitmap);
}
void
cogl_begin_gl (void)
{
CoglPipeline *pipeline;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->in_begin_gl_block)
{
static gboolean shown = FALSE;
if (!shown)
g_warning ("You should not nest cogl_begin_gl/cogl_end_gl blocks");
shown = TRUE;
return;
}
ctx->in_begin_gl_block = TRUE;
/* Flush all batched primitives */
cogl_flush ();
/* Flush framebuffer state, including clip state, modelview and
* projection matrix state
*
* NB: _cogl_framebuffer_flush_state may disrupt various state (such
* as the pipeline state) when flushing the clip stack, so should
* always be done first when preparing to draw. */
_cogl_framebuffer_flush_state (cogl_get_draw_framebuffer (),
_cogl_get_read_framebuffer (),
COGL_FRAMEBUFFER_STATE_ALL);
/* Setup the state for the current pipeline */
/* We considered flushing a specific, minimal pipeline here to try and
* simplify the GL state, but decided to avoid special cases and second
* guessing what would be actually helpful.
*
* A user should instead call cogl_set_source_color4ub() before
* cogl_begin_gl() to simplify the state flushed.
*
* XXX: note defining n_tex_coord_attribs using
* cogl_pipeline_get_n_layers is a hack, but the problem is that
* n_tex_coord_attribs is usually defined when drawing a primitive
* which isn't happening here.
*
* Maybe it would be more useful if this code did flush the
* opaque_color_pipeline and then call into cogl-pipeline-opengl.c to then
* restore all state for the material's backend back to default OpenGL
* values.
*/
pipeline = cogl_get_source ();
_cogl_pipeline_flush_gl_state (pipeline,
FALSE,
cogl_pipeline_get_n_layers (pipeline));
/* Disable any cached vertex arrays */
_cogl_attribute_disable_cached_arrays ();
}
void
cogl_end_gl (void)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (!ctx->in_begin_gl_block)
{
static gboolean shown = FALSE;
if (!shown)
g_warning ("cogl_end_gl is being called before cogl_begin_gl");
shown = TRUE;
return;
}
ctx->in_begin_gl_block = FALSE;
}
void
cogl_push_matrix (void)
{
cogl_framebuffer_push_matrix (cogl_get_draw_framebuffer ());
}
void
cogl_pop_matrix (void)
{
cogl_framebuffer_pop_matrix (cogl_get_draw_framebuffer ());
}
void
cogl_scale (float x, float y, float z)
{
cogl_framebuffer_scale (cogl_get_draw_framebuffer (), x, y, z);
}
void
cogl_translate (float x, float y, float z)
{
cogl_framebuffer_translate (cogl_get_draw_framebuffer (), x, y, z);
}
void
cogl_rotate (float angle, float x, float y, float z)
{
cogl_framebuffer_rotate (cogl_get_draw_framebuffer (), angle, x, y, z);
}
void
cogl_transform (const CoglMatrix *matrix)
{
cogl_framebuffer_transform (cogl_get_draw_framebuffer (), matrix);
}
void
cogl_perspective (float fov_y,
float aspect,
float z_near,
float z_far)
{
cogl_framebuffer_perspective (cogl_get_draw_framebuffer (),
fov_y, aspect, z_near, z_far);
}
void
cogl_frustum (float left,
float right,
float bottom,
float top,
float z_near,
float z_far)
{
cogl_framebuffer_frustum (cogl_get_draw_framebuffer (),
left, right, bottom, top, z_near, z_far);
}
void
cogl_ortho (float left,
float right,
float bottom,
float top,
float near,
float far)
{
cogl_framebuffer_orthographic (cogl_get_draw_framebuffer (),
left, top, right, bottom, near, far);
}
void
cogl_get_modelview_matrix (CoglMatrix *matrix)
{
cogl_framebuffer_get_modelview_matrix (cogl_get_draw_framebuffer (), matrix);
}
void
cogl_set_modelview_matrix (CoglMatrix *matrix)
{
cogl_framebuffer_set_modelview_matrix (cogl_get_draw_framebuffer (), matrix);
}
void
cogl_get_projection_matrix (CoglMatrix *matrix)
{
cogl_framebuffer_get_projection_matrix (cogl_get_draw_framebuffer (), matrix);
}
void
cogl_set_projection_matrix (CoglMatrix *matrix)
{
cogl_framebuffer_set_projection_matrix (cogl_get_draw_framebuffer (), matrix);
}
GQuark
_cogl_driver_error_quark (void)
{
return g_quark_from_static_string ("cogl-driver-error-quark");
}
typedef struct _CoglSourceState
{
CoglPipeline *pipeline;
int push_count;
/* If this is TRUE then the pipeline will be copied and the legacy
state will be applied whenever the pipeline is used. This is
necessary because some internal Cogl code expects to be able to
push a temporary pipeline to put GL into a known state. For that
to work it also needs to prevent applying the legacy state */
gboolean enable_legacy;
} CoglSourceState;
static void
_push_source_real (CoglPipeline *pipeline, gboolean enable_legacy)
{
CoglSourceState *top = g_slice_new (CoglSourceState);
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
top->pipeline = cogl_object_ref (pipeline);
top->enable_legacy = enable_legacy;
top->push_count = 1;
ctx->source_stack = g_list_prepend (ctx->source_stack, top);
}
/* FIXME: This should take a context pointer for Cogl 2.0 Technically
* we could make it so we can retrieve a context reference from the
* pipeline, but this would not by symmetric with cogl_pop_source. */
void
cogl_push_source (void *material_or_pipeline)
{
CoglPipeline *pipeline = COGL_PIPELINE (material_or_pipeline);
_COGL_RETURN_IF_FAIL (cogl_is_pipeline (pipeline));
_cogl_push_source (pipeline, TRUE);
}
/* This internal version of cogl_push_source is the same except it
never applies the legacy state. Some parts of Cogl use this
internally to set a temporary pipeline with a known state */
void
_cogl_push_source (CoglPipeline *pipeline, gboolean enable_legacy)
{
CoglSourceState *top;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
_COGL_RETURN_IF_FAIL (cogl_is_pipeline (pipeline));
if (ctx->source_stack)
{
top = ctx->source_stack->data;
if (top->pipeline == pipeline && top->enable_legacy == enable_legacy)
{
top->push_count++;
return;
}
else
_push_source_real (pipeline, enable_legacy);
}
else
_push_source_real (pipeline, enable_legacy);
}
/* FIXME: This needs to take a context pointer for Cogl 2.0 */
void
cogl_pop_source (void)
{
CoglSourceState *top;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
_COGL_RETURN_IF_FAIL (ctx->source_stack);
top = ctx->source_stack->data;
top->push_count--;
if (top->push_count == 0)
{
cogl_object_unref (top->pipeline);
g_slice_free (CoglSourceState, top);
ctx->source_stack = g_list_delete_link (ctx->source_stack,
ctx->source_stack);
}
}
/* FIXME: This needs to take a context pointer for Cogl 2.0 */
void *
cogl_get_source (void)
{
CoglSourceState *top;
_COGL_GET_CONTEXT (ctx, NULL);
_COGL_RETURN_VAL_IF_FAIL (ctx->source_stack, NULL);
top = ctx->source_stack->data;
return top->pipeline;
}
gboolean
_cogl_get_enable_legacy_state (void)
{
CoglSourceState *top;
_COGL_GET_CONTEXT (ctx, FALSE);
_COGL_RETURN_VAL_IF_FAIL (ctx->source_stack, FALSE);
top = ctx->source_stack->data;
return top->enable_legacy;
}
void
cogl_set_source (void *material_or_pipeline)
{
CoglSourceState *top;
CoglPipeline *pipeline = COGL_PIPELINE (material_or_pipeline);
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
_COGL_RETURN_IF_FAIL (cogl_is_pipeline (pipeline));
_COGL_RETURN_IF_FAIL (ctx->source_stack);
top = ctx->source_stack->data;
if (top->pipeline == pipeline && top->enable_legacy)
return;
if (top->push_count == 1)
{
/* NB: top->pipeline may be only thing keeping pipeline
* alive currently so ref pipeline first... */
cogl_object_ref (pipeline);
cogl_object_unref (top->pipeline);
top->pipeline = pipeline;
top->enable_legacy = TRUE;
}
else
{
top->push_count--;
cogl_push_source (pipeline);
}
}
void
cogl_set_source_texture (CoglTexture *texture)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
_COGL_RETURN_IF_FAIL (texture != NULL);
cogl_pipeline_set_layer_texture (ctx->texture_pipeline, 0, texture);
cogl_set_source (ctx->texture_pipeline);
}
void
cogl_set_source_color4ub (guint8 red,
guint8 green,
guint8 blue,
guint8 alpha)
{
CoglColor c = { 0, };
cogl_color_init_from_4ub (&c, red, green, blue, alpha);
cogl_set_source_color (&c);
}
void
cogl_set_source_color4f (float red,
float green,
float blue,
float alpha)
{
CoglColor c = { 0, };
cogl_color_init_from_4f (&c, red, green, blue, alpha);
cogl_set_source_color (&c);
}
/* Scale from OpenGL normalized device coordinates (ranging from -1 to 1)
* to Cogl window/framebuffer coordinates (ranging from 0 to buffer-size) with
* (0,0) being top left. */
#define VIEWPORT_TRANSFORM_X(x, vp_origin_x, vp_width) \
( ( ((x) + 1.0) * ((vp_width) / 2.0) ) + (vp_origin_x) )
/* Note: for Y we first flip all coordinates around the X axis while in
* normalized device coodinates */
#define VIEWPORT_TRANSFORM_Y(y, vp_origin_y, vp_height) \
( ( ((-(y)) + 1.0) * ((vp_height) / 2.0) ) + (vp_origin_y) )
/* Transform a homogeneous vertex position from model space to Cogl
* window coordinates (with 0,0 being top left) */
void
_cogl_transform_point (const CoglMatrix *matrix_mv,
const CoglMatrix *matrix_p,
const float *viewport,
float *x,
float *y)
{
float z = 0;
float w = 1;
/* Apply the modelview matrix transform */
cogl_matrix_transform_point (matrix_mv, x, y, &z, &w);
/* Apply the projection matrix transform */
cogl_matrix_transform_point (matrix_p, x, y, &z, &w);
/* Perform perspective division */
*x /= w;
*y /= w;
/* Apply viewport transform */
*x = VIEWPORT_TRANSFORM_X (*x, viewport[0], viewport[2]);
*y = VIEWPORT_TRANSFORM_Y (*y, viewport[1], viewport[3]);
}
#undef VIEWPORT_TRANSFORM_X
#undef VIEWPORT_TRANSFORM_Y
GQuark
_cogl_error_quark (void)
{
return g_quark_from_static_string ("cogl-error-quark");
}
void
_cogl_init (void)
{
static gsize init_status = 0;
if (g_once_init_enter (&init_status))
{
bindtextdomain (GETTEXT_PACKAGE, COGL_LOCALEDIR);
bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
g_type_init ();
_cogl_config_read ();
_cogl_debug_check_environment ();
g_once_init_leave (&init_status, 1);
}
}
/*
* Returns the number of bytes-per-pixel of a given format. The bpp
* can be extracted from the least significant nibble of the pixel
* format (see CoglPixelFormat).
*
* The mapping is the following (see discussion on bug #660188):
*
* 0 = undefined
* 1, 8 = 1 bpp (e.g. A_8, G_8)
* 2 = 3 bpp, aligned (e.g. 888)
* 3 = 4 bpp, aligned (e.g. 8888)
* 4-6 = 2 bpp, not aligned (e.g. 565, 4444, 5551)
* 7 = undefined yuv
* 9 = 2 bpp, aligned
* 10 = undefined
* 11 = undefined
* 12 = 3 bpp, not aligned
* 13 = 4 bpp, not aligned (e.g. 2101010)
* 14-15 = undefined
*/
int
_cogl_pixel_format_get_bytes_per_pixel (CoglPixelFormat format)
{
int bpp_lut[] = { 0, 1, 3, 4,
2, 2, 2, 0,
1, 2, 0, 0,
3, 4, 0, 0 };
return bpp_lut [format & 0xf];
}
/* Note: this also refers to the mapping defined above for
* _cogl_pixel_format_get_bytes_per_pixel() */
gboolean
_cogl_pixel_format_is_endian_dependant (CoglPixelFormat format)
{
int aligned_lut[] = { -1, 1, 1, 1,
0, 0, 0, -1,
1, 1, -1, -1,
0, 0, -1, -1};
int aligned = aligned_lut[format & 0xf];
_COGL_RETURN_VAL_IF_FAIL (aligned != -1, FALSE);
/* NB: currently checking whether the format components are aligned
* or not determines whether the format is endian dependent or not.
* In the future though we might consider adding formats with
* aligned components that are also endian independant. */
return aligned;
}