mutter/cogl/cogl-bitmap-pixbuf.c
Robert Bragg df21e20f65 Adds CoglError api
Although we use GLib internally in Cogl we would rather not leak GLib
api through Cogl's own api, except through explicitly namespaced
cogl_glib_ / cogl_gtype_ feature apis.

One of the benefits we see to not leaking GLib through Cogl's public API
is that documentation for Cogl won't need to first introduce the Glib
API to newcomers, thus hopefully lowering the barrier to learning Cogl.

This patch provides a Cogl specific typedef for reporting runtime errors
which by no coincidence matches the typedef for GError exactly.  If Cogl
is built with --enable-glib (default) then developers can even safely
assume that a CoglError is a GError under the hood.

This patch also enforces a consistent policy for when NULL is passed as
an error argument and an error is thrown. In this case we log the error
and abort the application, instead of silently ignoring it. In common
cases where nothing has been implemented to handle a particular error
and/or where applications are just printing the error and aborting
themselves then this saves some typing. This also seems more consistent
with language based exceptions which usually cause a program to abort if
they are not explicitly caught (which passing a non-NULL error signifies
in this case)

Since this policy for NULL error pointers is stricter than the standard
GError convention, there is a clear note in the documentation to warn
developers that are used to using the GError api.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit b068d5ea09ab32c37e8c965fc8582c85d1b2db46)

Note: Since we can't change the Cogl 1.x api the patch was changed to
not rename _error_quark() functions to be _error_domain() functions and
although it's a bit ugly, instead of providing our own CoglError type
that's compatible with GError we simply #define CoglError to GError
unless Cogl is built with glib disabled.

Note: this patch does technically introduce an API break since it drops
the cogl_error_get_type() symbol generated by glib-mkenum (Since the
CoglError enum was replaced by a CoglSystemError enum) but for now we
are assuming that this will not affect anyone currently using the Cogl
API. If this does turn out to be a problem in practice then we would be
able to fix this my manually copying an implementation of
cogl_error_get_type() generated by glib-mkenum into a compatibility
source file and we could also define the original COGL_ERROR_ enums for
compatibility too.

Note: another minor concern with cherry-picking this patch to the 1.14
branch is that an api scanner would be lead to believe that some APIs
have changed, and for example the gobject-introspection parser which
understands the semantics of GError will not understand the semantics of
CoglError. We expect most people that have tried to use
gobject-introspection with Cogl already understand though that it is not
well suited to generating bindings of the Cogl api anyway and we aren't
aware or anyone depending on such bindings for apis involving GErrors.
(GnomeShell only makes very-very minimal use of Cogl via the gjs
bindings for the cogl_rectangle and cogl_color apis.)

The main reason we have cherry-picked this patch to the 1.14 branch
even given the above concerns is that without it it would become very
awkward for us to cherry-pick other beneficial patches from master.
2013-01-22 17:47:39 +00:00

457 lines
13 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-util.h"
#include "cogl-internal.h"
#include "cogl-bitmap-private.h"
#include "cogl-context-private.h"
#include "cogl-private.h"
#include "cogl-error-private.h"
#include <string.h>
#ifdef USE_QUARTZ
#include <ApplicationServices/ApplicationServices.h>
#elif defined(USE_GDKPIXBUF)
#include <gdk-pixbuf/gdk-pixbuf.h>
#endif
#ifdef USE_QUARTZ
CoglBool
_cogl_bitmap_get_size_from_file (const char *filename,
int *width,
int *height)
{
if (width)
*width = 0;
if (height)
*height = 0;
return TRUE;
}
/* the error does not contain the filename as the caller already has it */
CoglBitmap *
_cogl_bitmap_from_file (CoglContext *ctx,
const char *filename,
CoglError **error)
{
CFURLRef url;
CGImageSourceRef image_source;
CGImageRef image;
int save_errno;
CFStringRef type;
size_t width, height, rowstride;
uint8_t *out_data;
CGColorSpaceRef color_space;
CGContextRef bitmap_context;
CoglBitmap *bmp;
url = CFURLCreateFromFileSystemRepresentation (NULL,
(guchar *) filename,
strlen (filename),
false);
image_source = CGImageSourceCreateWithURL (url, NULL);
save_errno = errno;
CFRelease (url);
if (image_source == NULL)
{
/* doesn't exist, not readable, etc. */
_cogl_set_error_literal (error,
COGL_BITMAP_ERROR,
COGL_BITMAP_ERROR_FAILED,
g_strerror (save_errno));
return NULL;
}
/* Unknown images would be cleanly caught as zero width/height below, but try
* to provide better error message
*/
type = CGImageSourceGetType (image_source);
if (type == NULL)
{
CFRelease (image_source);
_cogl_set_error_literal (error,
COGL_BITMAP_ERROR,
COGL_BITMAP_ERROR_UNKNOWN_TYPE,
"Unknown image type");
return NULL;
}
CFRelease (type);
image = CGImageSourceCreateImageAtIndex (image_source, 0, NULL);
CFRelease (image_source);
width = CGImageGetWidth (image);
height = CGImageGetHeight (image);
if (width == 0 || height == 0)
{
/* incomplete or corrupt */
CFRelease (image);
_cogl_set_error_literal (error,
COGL_BITMAP_ERROR,
COGL_BITMAP_ERROR_CORRUPT_IMAGE,
"Image has zero width or height");
return NULL;
}
/* allocate buffer big enough to hold pixel data */
bmp = _cogl_bitmap_new_with_malloc_buffer (ctx,
width, height,
COGL_PIXEL_FORMAT_ARGB_8888);
rowstride = cogl_bitmap_get_rowstride (bmp);
out_data = _cogl_bitmap_map (bmp,
COGL_BUFFER_ACCESS_WRITE,
COGL_BUFFER_MAP_HINT_DISCARD);
/* render to buffer */
color_space = CGColorSpaceCreateWithName (kCGColorSpaceGenericRGB);
bitmap_context = CGBitmapContextCreate (out_data,
width, height, 8,
rowstride, color_space,
kCGImageAlphaPremultipliedFirst);
CGColorSpaceRelease (color_space);
CGContextSetBlendMode (bitmap_context, kCGBlendModeCopy);
{
const CGRect rect = {{0, 0}, {width, height}};
CGContextDrawImage (bitmap_context, rect, image);
}
CGImageRelease (image);
CGContextRelease (bitmap_context);
_cogl_bitmap_unmap (bmp);
/* store bitmap info */
return bmp;
}
#elif defined(USE_GDKPIXBUF)
CoglBool
_cogl_bitmap_get_size_from_file (const char *filename,
int *width,
int *height)
{
_COGL_RETURN_VAL_IF_FAIL (filename != NULL, FALSE);
if (gdk_pixbuf_get_file_info (filename, width, height) != NULL)
return TRUE;
return FALSE;
}
CoglBitmap *
_cogl_bitmap_from_file (CoglContext *ctx,
const char *filename,
CoglError **error)
{
static CoglUserDataKey pixbuf_key;
GdkPixbuf *pixbuf;
CoglBool has_alpha;
GdkColorspace color_space;
CoglPixelFormat pixel_format;
int width;
int height;
int rowstride;
int bits_per_sample;
int n_channels;
CoglBitmap *bmp;
GError *glib_error = NULL;
/* Load from file using GdkPixbuf */
pixbuf = gdk_pixbuf_new_from_file (filename, &glib_error);
if (pixbuf == NULL)
{
_cogl_propogate_gerror (error, glib_error);
return FALSE;
}
/* Get pixbuf properties */
has_alpha = gdk_pixbuf_get_has_alpha (pixbuf);
color_space = gdk_pixbuf_get_colorspace (pixbuf);
width = gdk_pixbuf_get_width (pixbuf);
height = gdk_pixbuf_get_height (pixbuf);
rowstride = gdk_pixbuf_get_rowstride (pixbuf);
bits_per_sample = gdk_pixbuf_get_bits_per_sample (pixbuf);
n_channels = gdk_pixbuf_get_n_channels (pixbuf);
/* According to current docs this should be true and so
* the translation to cogl pixel format below valid */
g_assert (bits_per_sample == 8);
if (has_alpha)
g_assert (n_channels == 4);
else
g_assert (n_channels == 3);
/* Translate to cogl pixel format */
switch (color_space)
{
case GDK_COLORSPACE_RGB:
/* The only format supported by GdkPixbuf so far */
pixel_format = has_alpha ?
COGL_PIXEL_FORMAT_RGBA_8888 :
COGL_PIXEL_FORMAT_RGB_888;
break;
default:
/* Ouch, spec changed! */
g_object_unref (pixbuf);
return FALSE;
}
/* We just use the data directly from the pixbuf so that we don't
have to copy to a seperate buffer. Note that Cogl is expected not
to read past the end of bpp*width on the last row even if the
rowstride is much larger so we don't need to worry about
GdkPixbuf's semantics that it may under-allocate the buffer. */
bmp = cogl_bitmap_new_for_data (ctx,
width,
height,
pixel_format,
rowstride,
gdk_pixbuf_get_pixels (pixbuf));
cogl_object_set_user_data (COGL_OBJECT (bmp),
&pixbuf_key,
pixbuf,
g_object_unref);
return bmp;
}
#else
#include "stb_image.c"
CoglBool
_cogl_bitmap_get_size_from_file (const char *filename,
int *width,
int *height)
{
if (width)
*width = 0;
if (height)
*height = 0;
return TRUE;
}
/* stb_image.c supports an STBI_grey_alpha format which we don't have
* a corresponding CoglPixelFormat for so as a special case we
* convert this to rgba8888.
*
* If we have a use case where this is an important format to consider
* then it could be worth adding a corresponding CoglPixelFormat
* instead.
*/
static uint8_t *
convert_ra_88_to_rgba_8888 (uint8_t *pixels,
int width,
int height)
{
int x, y;
uint8_t *buf;
size_t in_stride = width * 2;
size_t out_stride = width * 4;
buf = malloc (width * height * 4);
if (buf)
return NULL;
for (y = 0; y < height; y++)
for (x = 0; x < width; x++)
{
uint8_t *src = pixels + in_stride * y + 2 * x;
uint8_t *dst = buf + out_stride * y + 4 * x;
dst[0] = src[0];
dst[1] = src[0];
dst[2] = src[0];
dst[3] = src[1];
}
return buf;
}
static CoglBitmap *
_cogl_bitmap_new_from_stb_pixels (CoglContext *ctx,
uint8_t *pixels,
int stb_pixel_format,
int width,
int height,
CoglError **error)
{
static CoglUserDataKey bitmap_data_key;
CoglBitmap *bmp;
CoglPixelFormat cogl_format;
size_t stride;
if (pixels == NULL)
{
_cogl_set_error_literal (error,
COGL_BITMAP_ERROR,
COGL_BITMAP_ERROR_FAILED,
"Failed to load image with stb image library");
return NULL;
}
switch (stb_pixel_format)
{
case STBI_grey:
cogl_format = COGL_PIXEL_FORMAT_A_8;
break;
case STBI_grey_alpha:
{
uint8_t *tmp = pixels;
pixels = convert_ra_88_to_rgba_8888 (pixels, width, height);
free (tmp);
if (!pixels)
{
_cogl_set_error_literal (error,
COGL_BITMAP_ERROR,
COGL_BITMAP_ERROR_FAILED,
"Failed to alloc memory to convert "
"gray_alpha to rgba8888");
return NULL;
}
cogl_format = COGL_PIXEL_FORMAT_RGBA_8888;
break;
}
case STBI_rgb:
cogl_format = COGL_PIXEL_FORMAT_RGB_888;
break;
case STBI_rgb_alpha:
cogl_format = COGL_PIXEL_FORMAT_RGBA_8888;
break;
default:
g_warn_if_reached ();
return NULL;
}
stride = width * _cogl_pixel_format_get_bytes_per_pixel (cogl_format);
/* Store bitmap info */
bmp = cogl_bitmap_new_for_data (ctx,
width, height,
cogl_format,
stride,
pixels);
/* Register a destroy function so the pixel data will be freed
automatically when the bitmap object is destroyed */
cogl_object_set_user_data (COGL_OBJECT (bmp), &bitmap_data_key, pixels, free);
return bmp;
}
CoglBitmap *
_cogl_bitmap_from_file (CoglContext *ctx,
const char *filename,
CoglError **error)
{
int stb_pixel_format;
int width;
int height;
uint8_t *pixels;
pixels = stbi_load (filename,
&width, &height, &stb_pixel_format,
STBI_default);
return _cogl_bitmap_new_from_stb_pixels (ctx, pixels, stb_pixel_format,
width, height,
error);
}
#ifdef COGL_HAS_ANDROID_SUPPORT
CoglBitmap *
_cogl_android_bitmap_new_from_asset (CoglContext *ctx,
AAssetManager *manager,
const char *filename,
CoglError **error)
{
AAsset *asset;
const void *data;
off_t len;
int stb_pixel_format;
int width;
int height;
uint8_t *pixels;
CoglBitmap *bmp;
asset = AAssetManager_open (manager, filename, AASSET_MODE_BUFFER);
if (!asset)
{
_cogl_set_error_literal (error,
COGL_BITMAP_ERROR,
COGL_BITMAP_ERROR_FAILED,
"Failed to open asset");
return NULL;
}
data = AAsset_getBuffer (asset);
if (!data)
{
_cogl_set_error_literal (error,
COGL_BITMAP_ERROR,
COGL_BITMAP_ERROR_FAILED,
"Failed to ::getBuffer from asset");
return NULL;
}
len = AAsset_getLength (asset);
pixels = stbi_load_from_memory (data, len,
&width, &height,
&stb_pixel_format, STBI_default);
bmp = _cogl_bitmap_new_from_stb_pixels (ctx, pixels, stb_pixel_format,
width, height,
error);
AAsset_close (asset);
return bmp;
}
#endif
#endif