/* Started from from http://www.gtkforums.com/about5204.html
* Author: tadeboro */
GdkPixbuf *
_gdk_pixbuf_new_from_cairo_surface (cairo_surface_t *surface)
{
int width;
int height;
int s_stride;
unsigned char *s_pixels;
GdkPixbuf *pixbuf;
int p_stride;
guchar *p_pixels;
int p_n_channels;
if (surface == NULL)
return NULL;
if (cairo_surface_status (surface) != CAIRO_STATUS_SUCCESS)
return NULL;
width = cairo_image_surface_get_width (surface);
height = cairo_image_surface_get_height (surface);
s_stride = cairo_image_surface_get_stride (surface);
s_pixels = _cairo_image_surface_flush_and_get_data (surface);
pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, _cairo_image_surface_get_has_alpha (surface), 8, width, height);
p_stride = gdk_pixbuf_get_rowstride (pixbuf);
p_pixels = gdk_pixbuf_get_pixels (pixbuf);
p_n_channels = gdk_pixbuf_get_n_channels (pixbuf);
while (height--) {
guchar *s_iter = s_pixels;
guchar *p_iter = p_pixels;
int i;
for (i = 0; i < width; i++) {
gdouble alpha_factor = (gdouble) 0xff / s_iter[CAIRO_ALPHA];
p_iter[0] = (guchar) (alpha_factor * s_iter[CAIRO_RED] + .5);
p_iter[1] = (guchar) (alpha_factor * s_iter[CAIRO_GREEN] + .5);
p_iter[2] = (guchar) (alpha_factor * s_iter[CAIRO_BLUE] + .5);
if (p_n_channels == 4)
p_iter[3] = s_iter[CAIRO_ALPHA];
s_iter += 4;
p_iter += p_n_channels;
}
s_pixels += s_stride;
p_pixels += p_stride;
}
return pixbuf;
}
static int
_WebPPictureImportCairoSurface (WebPPicture *const picture,
cairo_surface_t *image)
{
int stride;
guchar *src_row;
uint32_t *dest_row;
int y, x, temp;
guchar r, g, b, a;
if (_cairo_image_surface_get_has_alpha (image))
picture->colorspace |= WEBP_CSP_ALPHA_BIT;
else
picture->colorspace &= ~WEBP_CSP_ALPHA_BIT;
if (! WebPPictureAlloc (picture))
return 0;
stride = cairo_image_surface_get_stride (image);
src_row = _cairo_image_surface_flush_and_get_data (image);
dest_row = picture->argb;
for (y= 0; y < cairo_image_surface_get_height (image); y++) {
guchar *pixel = src_row;
for (x = 0; x < cairo_image_surface_get_width (image); x++) {
CAIRO_GET_RGBA (pixel, r, g, b, a);
dest_row[x] = ((a << 24) | (r << 16) | (g << 8) | b);
pixel += 4;
}
src_row += stride;
dest_row += picture->argb_stride;
}
return 1;
}
static gboolean
_cairo_surface_write_as_png (cairo_surface_t *image,
char **buffer,
gsize *buffer_size,
char **keys,
char **values,
GError **error)
{
int compression_level;
int width, height;
gboolean alpha;
guchar *pixels, *ptr, *buf;
int rowstride;
CairoPngData *cairo_png_data;
png_color_8 sig_bit;
int bpp;
int row;
compression_level = 6;
if (keys && *keys) {
char **kiter = keys;
char **viter = values;
while (*kiter) {
if (strcmp (*kiter, "compression") == 0) {
if (*viter == NULL) {
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_DATA,
"Must specify a compression level");
return FALSE;
}
compression_level = atoi (*viter);
if (compression_level < 0 || compression_level > 9) {
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_DATA,
"Unsupported compression level passed to the PNG saver");
return FALSE;
}
}
else {
g_warning ("Bad option name '%s' passed to the PNG saver", *kiter);
return FALSE;
}
++kiter;
++viter;
}
}
width = cairo_image_surface_get_width (image);
height = cairo_image_surface_get_height (image);
alpha = _cairo_image_surface_get_has_alpha (image);
pixels = _cairo_image_surface_flush_and_get_data (image);
rowstride = cairo_image_surface_get_stride (image);
cairo_png_data = g_new0 (CairoPngData, 1);
cairo_png_data->error = error;
cairo_png_data->buffer_data = gth_buffer_data_new ();
cairo_png_data->png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING,
&cairo_png_data->error,
gerror_error_func,
gerror_warning_func);
if (cairo_png_data->png_ptr == NULL) {
_cairo_png_data_destroy (cairo_png_data);
return FALSE;
}
cairo_png_data->png_info_ptr = png_create_info_struct (cairo_png_data->png_ptr);
if (cairo_png_data->png_info_ptr == NULL) {
_cairo_png_data_destroy (cairo_png_data);
return FALSE;
}
if (PNG_SETJMP (cairo_png_data->png_ptr)) {
_cairo_png_data_destroy (cairo_png_data);
return FALSE;
}
png_set_write_fn (cairo_png_data->png_ptr,
cairo_png_data,
cairo_png_write_data_func,
cairo_png_flush_data_func);
/* Set the image information here */
png_set_IHDR (cairo_png_data->png_ptr,
cairo_png_data->png_info_ptr,
width,
height,
8,
(alpha ? PNG_COLOR_TYPE_RGBA : PNG_COLOR_TYPE_RGB),
PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_BASE,
PNG_FILTER_TYPE_BASE);
/* Options */
sig_bit.red = 8;
sig_bit.green = 8;
sig_bit.blue = 8;
if (alpha)
sig_bit.alpha = 8;
png_set_sBIT (cairo_png_data->png_ptr, cairo_png_data->png_info_ptr, &sig_bit);
png_set_compression_level (cairo_png_data->png_ptr, compression_level);
/* Write the file header information. */
png_write_info (cairo_png_data->png_ptr, cairo_png_data->png_info_ptr);
/* Write the image */
bpp = alpha ? 4 : 3;
buf = g_new (guchar, width * bpp);
ptr = pixels;
for (row = 0; row < height; ++row) {
_cairo_copy_line_as_rgba_big_endian (buf, ptr, width, alpha);
png_write_rows (cairo_png_data->png_ptr, &buf, 1);
ptr += rowstride;
}
g_free (buf);
png_write_end (cairo_png_data->png_ptr, cairo_png_data->png_info_ptr);
gth_buffer_data_get (cairo_png_data->buffer_data, buffer, buffer_size);
_cairo_png_data_destroy (cairo_png_data);
return TRUE;
}
static gboolean
_cairo_surface_write_as_tga (cairo_surface_t *image,
char **buffer,
gsize *buffer_size,
char **keys,
char **values,
GError **error)
{
GthBufferData *buffer_data;
int out_bpp = 0;
int row;
guchar header[18];
guchar footer[26];
gboolean rle_compression;
gboolean alpha;
guchar *pixels, *ptr, *buf;
int width, height;
int rowstride;
rle_compression = TRUE;
if (keys && *keys) {
char **kiter = keys;
char **viter = values;
while (*kiter) {
if (strcmp (*kiter, "compression") == 0) {
if (*viter == NULL) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_BAD_OPTION,
"Must specify a compression type");
return FALSE;
}
if (strcmp (*viter, "none") == 0)
rle_compression = FALSE;
else if (strcmp (*viter, "rle") == 0)
rle_compression = TRUE;
else {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_BAD_OPTION,
"Unsupported compression type passed to the TGA saver");
return FALSE;
}
}
else {
g_warning ("Bad option name '%s' passed to the TGA saver", *kiter);
return FALSE;
}
++kiter;
++viter;
}
}
width = cairo_image_surface_get_width (image);
height = cairo_image_surface_get_height (image);
alpha = _cairo_image_surface_get_has_alpha (image);
pixels = _cairo_image_surface_flush_and_get_data (image);
rowstride = cairo_image_surface_get_stride (image);
buffer_data = gth_buffer_data_new ();
/* write the header */
header[0] = 0; /* No image identifier / description */
header[1] = 0;
header[2] = rle_compression ? 10 : 2;
header[3] = header[4] = header[5] = header[6] = header[7] = 0;
header[8] = header[9] = 0; /* xorigin */
header[10] = header[11] = 0; /* yorigin */
header[12] = width % 256;
header[13] = width / 256;
header[14] = height % 256;
header[15] = height / 256;
if (alpha) {
out_bpp = 4;
header[16] = 32; /* bpp */
header[17] = 0x28; /* alpha + orientation */
}
else {
out_bpp = 3;
header[16] = 24; /* bpp */
header[17] = 0x20; /* alpha + orientation */
}
gth_buffer_data_write (buffer_data, header, sizeof (header), error);
/* allocate a small buffer to convert image data */
buf = g_try_malloc (width * out_bpp * sizeof (guchar));
if (! buf) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Insufficient memory"));
return FALSE;
}
ptr = pixels;
for (row = 0; row < height; ++row) {
_cairo_copy_line_as_rgba_little_endian (buf, ptr, width, alpha);
if (rle_compression)
rle_write (buffer_data, buf, width, out_bpp, error);
else
gth_buffer_data_write (buffer_data, buf, width * out_bpp, error);
ptr += rowstride;
}
g_free (buf);
/* write the footer */
memset (footer, 0, 8); /* No extensions, no developer directory */
memcpy (footer + 8, magic, sizeof (magic)); /* magic signature */
gth_buffer_data_write (buffer_data, footer, sizeof (footer), error);
gth_buffer_data_get (buffer_data, buffer, buffer_size);
gth_buffer_data_free (buffer_data, FALSE);
return TRUE;
}
