tor-browser

pixman-image.c (25614B)

---

/*
* Copyright © 2000 SuSE, Inc.
* Copyright © 2007 Red Hat, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the name of SuSE not be used in advertising or
* publicity pertaining to distribution of the software without specific,
* written prior permission.  SuSE makes no representations about the
* suitability of this software for any purpose.  It is provided "as is"
* without express or implied warranty.
*
* SuSE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL SuSE
* BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

#ifdef HAVE_CONFIG_H
#include <pixman-config.h>
#endif

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>

#include "pixman-private.h"

static const pixman_color_t transparent_black = { 0, 0, 0, 0 };

static void
gradient_property_changed (pixman_image_t *image)
{
   gradient_t *gradient = &image->gradient;
   int n = gradient->n_stops;
   pixman_gradient_stop_t *stops = gradient->stops;
   pixman_gradient_stop_t *begin = &(gradient->stops[-1]);
   pixman_gradient_stop_t *end = &(gradient->stops[n]);

   switch (gradient->common.repeat)
   {
   default:
   case PIXMAN_REPEAT_NONE:
begin->x = INT32_MIN;
begin->color = transparent_black;
end->x = INT32_MAX;
end->color = transparent_black;
break;

   case PIXMAN_REPEAT_NORMAL:
begin->x = stops[n - 1].x - pixman_fixed_1;
begin->color = stops[n - 1].color;
end->x = stops[0].x + pixman_fixed_1;
end->color = stops[0].color;
break;

   case PIXMAN_REPEAT_REFLECT:
begin->x = - stops[0].x;
begin->color = stops[0].color;
end->x = pixman_int_to_fixed (2) - stops[n - 1].x;
end->color = stops[n - 1].color;
break;

   case PIXMAN_REPEAT_PAD:
begin->x = INT32_MIN;
begin->color = stops[0].color;
end->x = INT32_MAX;
end->color = stops[n - 1].color;
break;
   }
}

pixman_bool_t
_pixman_init_gradient (gradient_t *                  gradient,
                      const pixman_gradient_stop_t *stops,
                      int                           n_stops)
{
   return_val_if_fail (n_stops > 0, FALSE);

   /* We allocate two extra stops, one before the beginning of the stop list,
    * and one after the end. These stops are initialized to whatever color
    * would be used for positions outside the range of the stop list.
    *
    * This saves a bit of computation in the gradient walker.
    *
    * The pointer we store in the gradient_t struct still points to the
    * first user-supplied struct, so when freeing, we will have to
    * subtract one.
    */
   gradient->stops =
pixman_malloc_ab (n_stops + 2, sizeof (pixman_gradient_stop_t));
   if (!gradient->stops)
return FALSE;

   gradient->stops += 1;
   memcpy (gradient->stops, stops, n_stops * sizeof (pixman_gradient_stop_t));
   gradient->n_stops = n_stops;

   gradient->common.property_changed = gradient_property_changed;

   return TRUE;
}

void
_pixman_image_init (pixman_image_t *image)
{
   image_common_t *common = &image->common;

   pixman_region32_init (&common->clip_region);

   common->alpha_count = 0;
   common->have_clip_region = FALSE;
   common->clip_sources = FALSE;
   common->transform = NULL;
   common->repeat = PIXMAN_REPEAT_NONE;
   common->filter = PIXMAN_FILTER_NEAREST;
   common->filter_params = NULL;
   common->n_filter_params = 0;
   common->alpha_map = NULL;
   common->component_alpha = FALSE;
   common->ref_count = 1;
   common->property_changed = NULL;
   common->client_clip = FALSE;
   common->destroy_func = NULL;
   common->destroy_data = NULL;
   common->dirty = TRUE;
}

pixman_bool_t
_pixman_image_fini (pixman_image_t *image)
{
   image_common_t *common = (image_common_t *)image;

   common->ref_count--;

   if (common->ref_count == 0)
   {
if (image->common.destroy_func)
    image->common.destroy_func (image, image->common.destroy_data);

pixman_region32_fini (&common->clip_region);

free (common->transform);
free (common->filter_params);

if (common->alpha_map)
    pixman_image_unref ((pixman_image_t *)common->alpha_map);

if (image->type == LINEAR ||
    image->type == RADIAL ||
    image->type == CONICAL)
{
    if (image->gradient.stops)
    {
	/* See _pixman_init_gradient() for an explanation of the - 1 */
	free (image->gradient.stops - 1);
    }

    /* This will trigger if someone adds a property_changed
     * method to the linear/radial/conical gradient overwriting
     * the general one.
     */
    assert (
	image->common.property_changed == gradient_property_changed);
}

if (image->type == BITS && image->bits.free_me)
    free (image->bits.free_me);

return TRUE;
   }

   return FALSE;
}

pixman_image_t *
_pixman_image_allocate (void)
{
   pixman_image_t *image = malloc (sizeof (pixman_image_t));

   if (image)
_pixman_image_init (image);

   return image;
}

static void
image_property_changed (pixman_image_t *image)
{
   image->common.dirty = TRUE;
}

/* Ref Counting */
PIXMAN_EXPORT pixman_image_t *
pixman_image_ref (pixman_image_t *image)
{
   image->common.ref_count++;

   return image;
}

/* returns TRUE when the image is freed */
PIXMAN_EXPORT pixman_bool_t
pixman_image_unref (pixman_image_t *image)
{
   if (_pixman_image_fini (image))
   {
free (image);
return TRUE;
   }

   return FALSE;
}

PIXMAN_EXPORT void
pixman_image_set_destroy_function (pixman_image_t *            image,
                                  pixman_image_destroy_func_t func,
                                  void *                      data)
{
   image->common.destroy_func = func;
   image->common.destroy_data = data;
}

PIXMAN_EXPORT void *
pixman_image_get_destroy_data (pixman_image_t *image)
{
 return image->common.destroy_data;
}

void
_pixman_image_reset_clip_region (pixman_image_t *image)
{
   image->common.have_clip_region = FALSE;
}

/* Executive Summary: This function is a no-op that only exists
* for historical reasons.
*
* There used to be a bug in the X server where it would rely on
* out-of-bounds accesses when it was asked to composite with a
* window as the source. It would create a pixman image pointing
* to some bogus position in memory, but then set a clip region
* to the position where the actual bits were.
*
* Due to a bug in old versions of pixman, where it would not clip
* against the image bounds when a clip region was set, this would
* actually work. So when the pixman bug was fixed, a workaround was
* added to allow certain out-of-bound accesses. This function disabled
* those workarounds.
*
* Since 0.21.2, pixman doesn't do these workarounds anymore, so now
* this function is a no-op.
*/
PIXMAN_EXPORT void
pixman_disable_out_of_bounds_workaround (void)
{
}

static void
compute_image_info (pixman_image_t *image)
{
   pixman_format_code_t code;
   uint32_t flags = 0;

   /* Transform */
   if (!image->common.transform)
   {
flags |= (FAST_PATH_ID_TRANSFORM	|
	  FAST_PATH_X_UNIT_POSITIVE	|
	  FAST_PATH_Y_UNIT_ZERO		|
	  FAST_PATH_AFFINE_TRANSFORM);
   }
   else
   {
flags |= FAST_PATH_HAS_TRANSFORM;

if (image->common.transform->matrix[2][0] == 0			&&
    image->common.transform->matrix[2][1] == 0			&&
    image->common.transform->matrix[2][2] == pixman_fixed_1)
{
    flags |= FAST_PATH_AFFINE_TRANSFORM;

    if (image->common.transform->matrix[0][1] == 0 &&
	image->common.transform->matrix[1][0] == 0)
    {
	if (image->common.transform->matrix[0][0] == -pixman_fixed_1 &&
	    image->common.transform->matrix[1][1] == -pixman_fixed_1)
	{
	    flags |= FAST_PATH_ROTATE_180_TRANSFORM;
	}
	flags |= FAST_PATH_SCALE_TRANSFORM;
    }
    else if (image->common.transform->matrix[0][0] == 0 &&
             image->common.transform->matrix[1][1] == 0)
    {
	pixman_fixed_t m01 = image->common.transform->matrix[0][1];
	pixman_fixed_t m10 = image->common.transform->matrix[1][0];

	if (m01 == -pixman_fixed_1 && m10 == pixman_fixed_1)
	    flags |= FAST_PATH_ROTATE_90_TRANSFORM;
	else if (m01 == pixman_fixed_1 && m10 == -pixman_fixed_1)
	    flags |= FAST_PATH_ROTATE_270_TRANSFORM;
    }
}

if (image->common.transform->matrix[0][0] > 0)
    flags |= FAST_PATH_X_UNIT_POSITIVE;

if (image->common.transform->matrix[1][0] == 0)
    flags |= FAST_PATH_Y_UNIT_ZERO;
   }

   /* Filter */
   switch (image->common.filter)
   {
   case PIXMAN_FILTER_NEAREST:
   case PIXMAN_FILTER_FAST:
flags |= (FAST_PATH_NEAREST_FILTER | FAST_PATH_NO_CONVOLUTION_FILTER);
break;

   case PIXMAN_FILTER_BILINEAR:
   case PIXMAN_FILTER_GOOD:
   case PIXMAN_FILTER_BEST:
flags |= (FAST_PATH_BILINEAR_FILTER | FAST_PATH_NO_CONVOLUTION_FILTER);

/* Here we have a chance to optimize BILINEAR filter to NEAREST if
 * they are equivalent for the currently used transformation matrix.
 */
if (flags & FAST_PATH_ID_TRANSFORM)
{
    flags |= FAST_PATH_NEAREST_FILTER;
}
else if (flags & FAST_PATH_AFFINE_TRANSFORM)
{
    /* Suppose the transform is
     *
     *    [ t00, t01, t02 ]
     *    [ t10, t11, t12 ]
     *    [   0,   0,   1 ]
     *
     * and the destination coordinates are (n + 0.5, m + 0.5). Then
     * the transformed x coordinate is:
     *
     *     tx = t00 * (n + 0.5) + t01 * (m + 0.5) + t02
     *        = t00 * n + t01 * m + t02 + (t00 + t01) * 0.5
     *
     * which implies that if t00, t01 and t02 are all integers
     * and (t00 + t01) is odd, then tx will be an integer plus 0.5,
     * which means a BILINEAR filter will reduce to NEAREST. The same
     * applies in the y direction
     */
    pixman_fixed_t (*t)[3] = image->common.transform->matrix;

    if ((pixman_fixed_frac (
	     t[0][0] | t[0][1] | t[0][2] |
	     t[1][0] | t[1][1] | t[1][2]) == 0)			&&
	(pixman_fixed_to_int (
	    (t[0][0] + t[0][1]) & (t[1][0] + t[1][1])) % 2) == 1)
    {
	/* FIXME: there are some affine-test failures, showing that
	 * handling of BILINEAR and NEAREST filter is not quite
	 * equivalent when getting close to 32K for the translation
	 * components of the matrix. That's likely some bug, but for
	 * now just skip BILINEAR->NEAREST optimization in this case.
	 */
	pixman_fixed_t magic_limit = pixman_int_to_fixed (30000);
	if (image->common.transform->matrix[0][2] <= magic_limit  &&
	    image->common.transform->matrix[1][2] <= magic_limit  &&
	    image->common.transform->matrix[0][2] >= -magic_limit &&
	    image->common.transform->matrix[1][2] >= -magic_limit)
	{
	    flags |= FAST_PATH_NEAREST_FILTER;
	}
    }
}
break;

   case PIXMAN_FILTER_CONVOLUTION:
break;

   case PIXMAN_FILTER_SEPARABLE_CONVOLUTION:
flags |= FAST_PATH_SEPARABLE_CONVOLUTION_FILTER;
break;

   default:
flags |= FAST_PATH_NO_CONVOLUTION_FILTER;
break;
   }

   /* Repeat mode */
   switch (image->common.repeat)
   {
   case PIXMAN_REPEAT_NONE:
flags |=
    FAST_PATH_NO_REFLECT_REPEAT		|
    FAST_PATH_NO_PAD_REPEAT		|
    FAST_PATH_NO_NORMAL_REPEAT;
break;

   case PIXMAN_REPEAT_REFLECT:
flags |=
    FAST_PATH_NO_PAD_REPEAT		|
    FAST_PATH_NO_NONE_REPEAT		|
    FAST_PATH_NO_NORMAL_REPEAT;
break;

   case PIXMAN_REPEAT_PAD:
flags |=
    FAST_PATH_NO_REFLECT_REPEAT		|
    FAST_PATH_NO_NONE_REPEAT		|
    FAST_PATH_NO_NORMAL_REPEAT;
break;

   default:
flags |=
    FAST_PATH_NO_REFLECT_REPEAT		|
    FAST_PATH_NO_PAD_REPEAT		|
    FAST_PATH_NO_NONE_REPEAT;
break;
   }

   /* Component alpha */
   if (image->common.component_alpha)
flags |= FAST_PATH_COMPONENT_ALPHA;
   else
flags |= FAST_PATH_UNIFIED_ALPHA;

   flags |= (FAST_PATH_NO_ACCESSORS | FAST_PATH_NARROW_FORMAT);

   /* Type specific checks */
   switch (image->type)
   {
   case SOLID:
code = PIXMAN_solid;

if (image->solid.color.alpha == 0xffff)
    flags |= FAST_PATH_IS_OPAQUE;
break;

   case BITS:
if (image->bits.width == 1	&&
    image->bits.height == 1	&&
    image->common.repeat != PIXMAN_REPEAT_NONE)
{
    code = PIXMAN_solid;
}
else
{
    code = image->bits.format;
    flags |= FAST_PATH_BITS_IMAGE;
}

if (!PIXMAN_FORMAT_A (image->bits.format)				&&
    PIXMAN_FORMAT_TYPE (image->bits.format) != PIXMAN_TYPE_GRAY		&&
    PIXMAN_FORMAT_TYPE (image->bits.format) != PIXMAN_TYPE_COLOR)
{
    flags |= FAST_PATH_SAMPLES_OPAQUE;

    if (image->common.repeat != PIXMAN_REPEAT_NONE)
	flags |= FAST_PATH_IS_OPAQUE;
}

if (image->bits.read_func || image->bits.write_func)
    flags &= ~FAST_PATH_NO_ACCESSORS;

if (PIXMAN_FORMAT_IS_WIDE (image->bits.format))
    flags &= ~FAST_PATH_NARROW_FORMAT;
break;

   case RADIAL:
code = PIXMAN_unknown;

/*
 * As explained in pixman-radial-gradient.c, every point of
 * the plane has a valid associated radius (and thus will be
 * colored) if and only if a is negative (i.e. one of the two
 * circles contains the other one).
 */

       if (image->radial.a >= 0)
    break;

/* Fall through */

   case CONICAL:
   case LINEAR:
code = PIXMAN_unknown;

if (image->common.repeat != PIXMAN_REPEAT_NONE)
{
    int i;

    flags |= FAST_PATH_IS_OPAQUE;
    for (i = 0; i < image->gradient.n_stops; ++i)
    {
	if (image->gradient.stops[i].color.alpha != 0xffff)
	{
	    flags &= ~FAST_PATH_IS_OPAQUE;
	    break;
	}
    }
}
break;

   default:
code = PIXMAN_unknown;
break;
   }

   /* Alpha maps are only supported for BITS images, so it's always
    * safe to ignore their presense for non-BITS images
    */
   if (!image->common.alpha_map || image->type != BITS)
   {
flags |= FAST_PATH_NO_ALPHA_MAP;
   }
   else
   {
if (PIXMAN_FORMAT_IS_WIDE (image->common.alpha_map->format))
    flags &= ~FAST_PATH_NARROW_FORMAT;
   }

   /* Both alpha maps and convolution filters can introduce
    * non-opaqueness in otherwise opaque images. Also
    * an image with component alpha turned on is only opaque
    * if all channels are opaque, so we simply turn it off
    * unconditionally for those images.
    */
   if (image->common.alpha_map						||
image->common.filter == PIXMAN_FILTER_CONVOLUTION		||
       image->common.filter == PIXMAN_FILTER_SEPARABLE_CONVOLUTION     ||
image->common.component_alpha)
   {
flags &= ~(FAST_PATH_IS_OPAQUE | FAST_PATH_SAMPLES_OPAQUE);
   }

   image->common.flags = flags;
   image->common.extended_format_code = code;
}

void
_pixman_image_validate (pixman_image_t *image)
{
   if (image->common.dirty)
   {
compute_image_info (image);

/* It is important that property_changed is
 * called *after* compute_image_info() because
 * property_changed() can make use of the flags
 * to set up accessors etc.
 */
if (image->common.property_changed)
    image->common.property_changed (image);

image->common.dirty = FALSE;
   }

   if (image->common.alpha_map)
_pixman_image_validate ((pixman_image_t *)image->common.alpha_map);
}

PIXMAN_EXPORT pixman_bool_t
pixman_image_set_clip_region32 (pixman_image_t *   image,
                               const pixman_region32_t *region)
{
   image_common_t *common = (image_common_t *)image;
   pixman_bool_t result;

   if (region)
   {
if ((result = pixman_region32_copy (&common->clip_region, region)))
    image->common.have_clip_region = TRUE;
   }
   else
   {
_pixman_image_reset_clip_region (image);

result = TRUE;
   }

   image_property_changed (image);

   return result;
}

PIXMAN_EXPORT pixman_bool_t
pixman_image_set_clip_region (pixman_image_t *   image,
                             const pixman_region16_t *region)
{
   image_common_t *common = (image_common_t *)image;
   pixman_bool_t result;

   if (region)
   {
if ((result = pixman_region32_copy_from_region16 (&common->clip_region, region)))
    image->common.have_clip_region = TRUE;
   }
   else
   {
_pixman_image_reset_clip_region (image);

result = TRUE;
   }

   image_property_changed (image);

   return result;
}

PIXMAN_EXPORT pixman_bool_t
pixman_image_set_clip_region64f (pixman_image_t *   image,
                                const pixman_region64f_t *region)
{
   image_common_t *common = (image_common_t *)image;
   pixman_bool_t result;

   if (region)
   {
if ((result = pixman_region32_copy_from_region64f (&common->clip_region, region)))
    image->common.have_clip_region = TRUE;
   }
   else
   {
_pixman_image_reset_clip_region (image);

result = TRUE;
   }

   image_property_changed (image);

   return result;
}

PIXMAN_EXPORT void
pixman_image_set_has_client_clip (pixman_image_t *image,
                                 pixman_bool_t   client_clip)
{
   image->common.client_clip = client_clip;
}

PIXMAN_EXPORT pixman_bool_t
pixman_image_set_transform (pixman_image_t *          image,
                           const pixman_transform_t *transform)
{
   static const pixman_transform_t id =
   {
{ { pixman_fixed_1, 0, 0 },
  { 0, pixman_fixed_1, 0 },
  { 0, 0, pixman_fixed_1 } }
   };

   image_common_t *common = (image_common_t *)image;
   pixman_bool_t result;

   if (common->transform == transform)
return TRUE;

   if (!transform || memcmp (&id, transform, sizeof (pixman_transform_t)) == 0)
   {
free (common->transform);
common->transform = NULL;
result = TRUE;

goto out;
   }

   if (common->transform &&
memcmp (common->transform, transform, sizeof (pixman_transform_t)) == 0)
   {
return TRUE;
   }

   if (common->transform == NULL)
common->transform = malloc (sizeof (pixman_transform_t));

   if (common->transform == NULL)
   {
result = FALSE;

goto out;
   }

   memcpy (common->transform, transform, sizeof(pixman_transform_t));

   result = TRUE;

out:
   image_property_changed (image);

   return result;
}

PIXMAN_EXPORT void
pixman_image_set_repeat (pixman_image_t *image,
                        pixman_repeat_t repeat)
{
   if (image->common.repeat == repeat)
return;

   image->common.repeat = repeat;

   image_property_changed (image);
}

PIXMAN_EXPORT void
pixman_image_set_dither (pixman_image_t *image,
		 pixman_dither_t dither)
{
   if (image->type == BITS)
   {
if (image->bits.dither == dither)
    return;

image->bits.dither = dither;

image_property_changed (image);
   }
}

PIXMAN_EXPORT void
pixman_image_set_dither_offset (pixman_image_t *image,
			int             offset_x,
			int             offset_y)
{
   if (image->type == BITS)
   {
if (image->bits.dither_offset_x == offset_x &&
    image->bits.dither_offset_y == offset_y)
{
    return;
}

image->bits.dither_offset_x = offset_x;
image->bits.dither_offset_y = offset_y;

image_property_changed (image);
   }
}

PIXMAN_EXPORT pixman_bool_t
pixman_image_set_filter (pixman_image_t *      image,
                        pixman_filter_t       filter,
                        const pixman_fixed_t *params,
                        int                   n_params)
{
   image_common_t *common = (image_common_t *)image;
   pixman_fixed_t *new_params;

   if (params == common->filter_params && filter == common->filter)
return TRUE;

   if (filter == PIXMAN_FILTER_SEPARABLE_CONVOLUTION)
   {
int width = pixman_fixed_to_int (params[0]);
int height = pixman_fixed_to_int (params[1]);
int x_phase_bits = pixman_fixed_to_int (params[2]);
int y_phase_bits = pixman_fixed_to_int (params[3]);
int n_x_phases = (1 << x_phase_bits);
int n_y_phases = (1 << y_phase_bits);

return_val_if_fail (
    n_params == 4 + n_x_phases * width + n_y_phases * height, FALSE);
   }
   
   new_params = NULL;
   if (params)
   {
new_params = pixman_malloc_ab (n_params, sizeof (pixman_fixed_t));
if (!new_params)
    return FALSE;

memcpy (new_params,
        params, n_params * sizeof (pixman_fixed_t));
   }

   common->filter = filter;

   if (common->filter_params)
free (common->filter_params);

   common->filter_params = new_params;
   common->n_filter_params = n_params;

   image_property_changed (image);
   return TRUE;
}

PIXMAN_EXPORT void
pixman_image_set_source_clipping (pixman_image_t *image,
                                 pixman_bool_t   clip_sources)
{
   if (image->common.clip_sources == clip_sources)
return;

   image->common.clip_sources = clip_sources;

   image_property_changed (image);
}

/* Unlike all the other property setters, this function does not
* copy the content of indexed. Doing this copying is simply
* way, way too expensive.
*/
PIXMAN_EXPORT void
pixman_image_set_indexed (pixman_image_t *        image,
                         const pixman_indexed_t *indexed)
{
   bits_image_t *bits = (bits_image_t *)image;

   if (bits->indexed == indexed)
return;

   bits->indexed = indexed;

   image_property_changed (image);
}

PIXMAN_EXPORT void
pixman_image_set_alpha_map (pixman_image_t *image,
                           pixman_image_t *alpha_map,
                           int16_t         x,
                           int16_t         y)
{
   image_common_t *common = (image_common_t *)image;

   return_if_fail (!alpha_map || alpha_map->type == BITS);

   if (alpha_map && common->alpha_count > 0)
   {
/* If this image is being used as an alpha map itself,
 * then you can't give it an alpha map of its own.
 */
return;
   }

   if (alpha_map && alpha_map->common.alpha_map)
   {
/* If the image has an alpha map of its own,
 * then it can't be used as an alpha map itself
 */
return;
   }

   if (common->alpha_map != (bits_image_t *)alpha_map)
   {
if (common->alpha_map)
{
    common->alpha_map->common.alpha_count--;

    pixman_image_unref ((pixman_image_t *)common->alpha_map);
}

if (alpha_map)
{
    common->alpha_map = (bits_image_t *)pixman_image_ref (alpha_map);

    common->alpha_map->common.alpha_count++;
}
else
{
    common->alpha_map = NULL;
}
   }

   common->alpha_origin_x = x;
   common->alpha_origin_y = y;

   image_property_changed (image);
}

PIXMAN_EXPORT void
pixman_image_set_component_alpha   (pixman_image_t *image,
                                   pixman_bool_t   component_alpha)
{
   if (image->common.component_alpha == component_alpha)
return;

   image->common.component_alpha = component_alpha;

   image_property_changed (image);
}

PIXMAN_EXPORT pixman_bool_t
pixman_image_get_component_alpha   (pixman_image_t       *image)
{
   return image->common.component_alpha;
}

PIXMAN_EXPORT void
pixman_image_set_accessors (pixman_image_t *           image,
                           pixman_read_memory_func_t  read_func,
                           pixman_write_memory_func_t write_func)
{
   return_if_fail (image != NULL);

   if (image->type == BITS)
   {
/* Accessors only work for <= 32 bpp. */
if (PIXMAN_FORMAT_BPP(image->bits.format) > 32)
    return_if_fail (!read_func && !write_func);

image->bits.read_func = read_func;
image->bits.write_func = write_func;

image_property_changed (image);
   }
}

PIXMAN_EXPORT uint32_t *
pixman_image_get_data (pixman_image_t *image)
{
   if (image->type == BITS)
return image->bits.bits;

   return NULL;
}

PIXMAN_EXPORT int
pixman_image_get_width (pixman_image_t *image)
{
   if (image->type == BITS)
return image->bits.width;

   return 0;
}

PIXMAN_EXPORT int
pixman_image_get_height (pixman_image_t *image)
{
   if (image->type == BITS)
return image->bits.height;

   return 0;
}

PIXMAN_EXPORT int
pixman_image_get_stride (pixman_image_t *image)
{
   if (image->type == BITS)
return image->bits.rowstride * (int) sizeof (uint32_t);

   return 0;
}

PIXMAN_EXPORT int
pixman_image_get_depth (pixman_image_t *image)
{
   if (image->type == BITS)
return PIXMAN_FORMAT_DEPTH (image->bits.format);

   return 0;
}

PIXMAN_EXPORT pixman_format_code_t
pixman_image_get_format (pixman_image_t *image)
{
   if (image->type == BITS)
return image->bits.format;

   return PIXMAN_null;
}

uint32_t
_pixman_image_get_solid (pixman_implementation_t *imp,
		 pixman_image_t *         image,
                        pixman_format_code_t     format)
{
   uint32_t result;

   if (image->type == SOLID)
   {
result = image->solid.color_32;
   }
   else if (image->type == BITS)
   {
if (image->bits.format == PIXMAN_a8r8g8b8)
    result = image->bits.bits[0];
else if (image->bits.format == PIXMAN_x8r8g8b8)
    result = image->bits.bits[0] | 0xff000000;
else if (image->bits.format == PIXMAN_a8)
    result = (uint32_t)(*(uint8_t *)image->bits.bits) << 24;
else
    goto otherwise;
   }
   else
   {
pixman_iter_t iter;

   otherwise:
_pixman_implementation_iter_init (
    imp, &iter, image, 0, 0, 1, 1,
    (uint8_t *)&result,
    ITER_NARROW | ITER_SRC, image->common.flags);

result = *iter.get_scanline (&iter, NULL);

if (iter.fini)
    iter.fini (&iter);
   }

   /* If necessary, convert RGB <--> BGR. */
   if (PIXMAN_FORMAT_TYPE (format) != PIXMAN_TYPE_ARGB
&& PIXMAN_FORMAT_TYPE (format) != PIXMAN_TYPE_ARGB_SRGB)
   {
result = (((result & 0xff000000) >>  0) |
          ((result & 0x00ff0000) >> 16) |
          ((result & 0x0000ff00) >>  0) |
          ((result & 0x000000ff) << 16));
   }

   return result;
}