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/* GDK - The GIMP Drawing Kit
* Copyright (C) 2005 Red Hat, Inc.
*
* 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "gdkcairo.h"
#include "gdkdrawable.h"
#include "gdkinternals.h"
#include "gdkregion-generic.h"
#include "gdkalias.h"
/**
* gdk_cairo_create:
* @drawable: a #GdkDrawable
*
* Creates a Cairo context for drawing to @drawable.
*
* Return value: A newly created Cairo context. Free with
* cairo_destroy() when you are done drawing.
*
* Since: 2.8
**/
cairo_t *
gdk_cairo_create (GdkDrawable *drawable)
{
cairo_surface_t *surface;
cairo_t *cr;
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
surface = _gdk_drawable_ref_cairo_surface (drawable);
cr = cairo_create (surface);
cairo_surface_destroy (surface);
return cr;
}
/**
* gdk_cairo_set_source_color:
* @cr: a #cairo_t
* @color: a #GdkColor
*
* Sets the specified #GdkColor as the source color of @cr.
*
* Since: 2.8
**/
void
gdk_cairo_set_source_color (cairo_t *cr,
GdkColor *color)
{
g_return_if_fail (cr != NULL);
g_return_if_fail (color != NULL);
cairo_set_source_rgb (cr,
color->red / 65535.,
color->green / 65535.,
color->blue / 65535.);
}
/**
* gdk_cairo_rectangle:
* @cr: a #cairo_t
* @rectangle: a #GdkRectangle
*
* Adds the given rectangle to the current path of @cr.
*
* Since: 2.8
**/
void
gdk_cairo_rectangle (cairo_t *cr,
GdkRectangle *rectangle)
{
g_return_if_fail (cr != NULL);
g_return_if_fail (rectangle != NULL);
cairo_rectangle (cr,
rectangle->x, rectangle->y,
rectangle->width, rectangle->height);
}
/**
* gdk_cairo_region:
* @cr: a #cairo_t
* @region: a #GdkRegion
*
* Adds the given region to the current path of @cr.
*
* Since: 2.8
**/
void
gdk_cairo_region (cairo_t *cr,
GdkRegion *region)
{
GdkRegionBox *boxes;
gint n_boxes, i;
g_return_if_fail (cr != NULL);
g_return_if_fail (region != NULL);
boxes = region->rects;
n_boxes = region->numRects;
for (i = 0; i < n_boxes; i++)
cairo_rectangle (cr,
boxes[i].x1,
boxes[i].y1,
boxes[i].x2 - boxes[i].x1,
boxes[i].y2 - boxes[i].y1);
}
/**
* gdk_cairo_set_source_pixbuf:
* @cr: a #Cairo context
* @pixbuf: a #GdkPixbuf
* @pixbuf_x: X coordinate of location to place upper left corner of @pixbuf
* @pixbuf_y: Y coordinate of location to place upper left corner of @pixbuf
*
* Sets the given pixbuf as the source pattern for the Cairo context.
* The pattern has an extend mode of %CAIRO_EXTEND_NONE and is aligned
* so that the origin of @pixbuf is @pixbuf_x, @pixbuf_y
*
* Since: 2.8
**/
void
gdk_cairo_set_source_pixbuf (cairo_t *cr,
GdkPixbuf *pixbuf,
double pixbuf_x,
double pixbuf_y)
{
gint width = gdk_pixbuf_get_width (pixbuf);
gint height = gdk_pixbuf_get_height (pixbuf);
guchar *gdk_pixels = gdk_pixbuf_get_pixels (pixbuf);
int gdk_rowstride = gdk_pixbuf_get_rowstride (pixbuf);
int n_channels = gdk_pixbuf_get_n_channels (pixbuf);
guchar *cairo_pixels;
cairo_format_t format;
cairo_surface_t *surface;
static const cairo_user_data_key_t key;
int j;
if (n_channels == 3)
format = CAIRO_FORMAT_RGB24;
else
format = CAIRO_FORMAT_ARGB32;
cairo_pixels = g_malloc (4 * width * height);
surface = cairo_image_surface_create_for_data ((unsigned char *)cairo_pixels,
format,
width, height, 4 * width);
cairo_surface_set_user_data (surface, &key,
cairo_pixels, (cairo_destroy_func_t)g_free);
for (j = height; j; j--)
{
guchar *p = gdk_pixels;
guchar *q = cairo_pixels;
if (n_channels == 3)
{
guchar *end = p + 3 * width;
while (p < end)
{
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
q[0] = p[2];
q[1] = p[1];
q[2] = p[0];
#else
q[1] = p[0];
q[2] = p[1];
q[3] = p[2];
#endif
p += 3;
q += 4;
}
}
else
{
guchar *end = p + 4 * width;
guint t1,t2,t3;
#define MULT(d,c,a,t) G_STMT_START { t = c * a; d = ((t >> 8) + t) >> 8; } G_STMT_END
while (p < end)
{
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
MULT(q[0], p[2], p[3], t1);
MULT(q[1], p[1], p[3], t2);
MULT(q[2], p[0], p[3], t3);
q[3] = p[3];
#else
q[0] = p[3];
MULT(q[1], p[0], p[3], t1);
MULT(q[2], p[1], p[3], t2);
MULT(q[3], p[2], p[3], t3);
#endif
p += 4;
q += 4;
}
#undef MULT
}
gdk_pixels += gdk_rowstride;
cairo_pixels += 4 * width;
}
cairo_set_source_surface (cr, surface, pixbuf_x, pixbuf_y);
cairo_surface_destroy (surface);
}
#define __GDK_CAIRO_C__
#include "gdkaliasdef.c"
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