1 /* GDK - The GIMP Drawing Kit
2 * Copyright (C) 2005 Red Hat, Inc.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
21 #include "gdkdrawable.h"
22 #include "gdkinternals.h"
23 #include "gdkregion-generic.h"
28 * @drawable: a #GdkDrawable
30 * Creates a Cairo context for drawing to @drawable.
32 * Return value: A newly created Cairo context. Free with
33 * cairo_destroy() when you are done drawing.
38 gdk_cairo_create (GdkDrawable *drawable)
40 cairo_surface_t *surface;
43 g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
45 surface = _gdk_drawable_ref_cairo_surface (drawable);
46 cr = cairo_create (surface);
47 cairo_surface_destroy (surface);
53 * gdk_cairo_set_source_color:
57 * Sets the specified #GdkColor as the source color of @cr.
62 gdk_cairo_set_source_color (cairo_t *cr,
65 g_return_if_fail (cr != NULL);
66 g_return_if_fail (color != NULL);
68 cairo_set_source_rgb (cr,
70 color->green / 65535.,
71 color->blue / 65535.);
75 * gdk_cairo_rectangle:
77 * @rectangle: a #GdkRectangle
79 * Adds the given rectangle to the current path of @cr.
84 gdk_cairo_rectangle (cairo_t *cr,
85 GdkRectangle *rectangle)
87 g_return_if_fail (cr != NULL);
88 g_return_if_fail (rectangle != NULL);
91 rectangle->x, rectangle->y,
92 rectangle->width, rectangle->height);
98 * @region: a #GdkRegion
100 * Adds the given region to the current path of @cr.
105 gdk_cairo_region (cairo_t *cr,
111 g_return_if_fail (cr != NULL);
112 g_return_if_fail (region != NULL);
114 boxes = region->rects;
115 n_boxes = region->numRects;
117 for (i = 0; i < n_boxes; i++)
121 boxes[i].x2 - boxes[i].x1,
122 boxes[i].y2 - boxes[i].y1);
126 * gdk_cairo_set_source_pixbuf:
127 * @cr: a #Cairo context
128 * @pixbuf: a #GdkPixbuf
129 * @pixbuf_x: X coordinate of location to place upper left corner of @pixbuf
130 * @pixbuf_y: Y coordinate of location to place upper left corner of @pixbuf
132 * Sets the given pixbuf as the source pattern for the Cairo context.
133 * The pattern has an extend mode of %CAIRO_EXTEND_NONE and is aligned
134 * so that the origin of @pixbuf is @pixbuf_x, @pixbuf_y
139 gdk_cairo_set_source_pixbuf (cairo_t *cr,
144 gint width = gdk_pixbuf_get_width (pixbuf);
145 gint height = gdk_pixbuf_get_height (pixbuf);
146 guchar *gdk_pixels = gdk_pixbuf_get_pixels (pixbuf);
147 int gdk_rowstride = gdk_pixbuf_get_rowstride (pixbuf);
148 int n_channels = gdk_pixbuf_get_n_channels (pixbuf);
149 guchar *cairo_pixels;
150 cairo_format_t format;
151 cairo_surface_t *surface;
152 static const cairo_user_data_key_t key;
156 format = CAIRO_FORMAT_RGB24;
158 format = CAIRO_FORMAT_ARGB32;
160 cairo_pixels = g_malloc (4 * width * height);
161 surface = cairo_image_surface_create_for_data ((unsigned char *)cairo_pixels,
163 width, height, 4 * width);
164 cairo_surface_set_user_data (surface, &key,
165 cairo_pixels, (cairo_destroy_func_t)g_free);
167 for (j = height; j; j--)
169 guchar *p = gdk_pixels;
170 guchar *q = cairo_pixels;
174 guchar *end = p + 3 * width;
178 #if G_BYTE_ORDER == G_LITTLE_ENDIAN
193 guchar *end = p + 4 * width;
196 #define MULT(d,c,a,t) G_STMT_START { t = c * a; d = ((t >> 8) + t) >> 8; } G_STMT_END
200 #if G_BYTE_ORDER == G_LITTLE_ENDIAN
201 MULT(q[0], p[2], p[3], t1);
202 MULT(q[1], p[1], p[3], t2);
203 MULT(q[2], p[0], p[3], t3);
207 MULT(q[1], p[0], p[3], t1);
208 MULT(q[2], p[1], p[3], t2);
209 MULT(q[3], p[2], p[3], t3);
219 gdk_pixels += gdk_rowstride;
220 cairo_pixels += 4 * width;
223 cairo_set_source_surface (cr, surface, pixbuf_x, pixbuf_y);
224 cairo_surface_destroy (surface);
228 * gdk_cairo_set_source_pixmap:
229 * @cr: a #Cairo context
230 * @pixmap: a #GdkPixmap
231 * @pixmap_x: X coordinate of location to place upper left corner of @pixmap
232 * @pixmap_y: Y coordinate of location to place upper left corner of @pixmap
234 * Sets the given pixmap as the source pattern for the Cairo context.
235 * The pattern has an extend mode of %CAIRO_EXTEND_NONE and is aligned
236 * so that the origin of @pixbuf is @pixbuf_x, @pixbuf_y
241 gdk_cairo_set_source_pixmap (cairo_t *cr,
246 cairo_surface_t *surface;
248 surface = _gdk_drawable_ref_cairo_surface (GDK_DRAWABLE (pixmap));
249 cairo_set_source_surface (cr, surface, pixmap_x, pixmap_y);
250 cairo_surface_destroy (surface);
254 #define __GDK_CAIRO_C__
255 #include "gdkaliasdef.c"