src/cairo-clip-surface.c

   1 /* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */
   2 /* cairo - a vector graphics library with display and print output
   3  *
   4  * Copyright © 2002 University of Southern California
   5  * Copyright © 2005 Red Hat, Inc.
   6  * Copyright © 2009 Chris Wilson
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it either under the terms of the GNU Lesser General Public
  10  * License version 2.1 as published by the Free Software Foundation
  11  * (the "LGPL") or, at your option, under the terms of the Mozilla
  12  * Public License Version 1.1 (the "MPL"). If you do not alter this
  13  * notice, a recipient may use your version of this file under either
  14  * the MPL or the LGPL.
  15  *
  16  * You should have received a copy of the LGPL along with this library
  17  * in the file COPYING-LGPL-2.1; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
  19  * You should have received a copy of the MPL along with this library
  20  * in the file COPYING-MPL-1.1
  21  *
  22  * The contents of this file are subject to the Mozilla Public License
  23  * Version 1.1 (the "License"); you may not use this file except in
  24  * compliance with the License. You may obtain a copy of the License at
  25  * http://www.mozilla.org/MPL/
  26  *
  27  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
  28  * OF ANY KIND, either express or implied. See the LGPL or the MPL for
  29  * the specific language governing rights and limitations.
  30  *
  31  * The Original Code is the cairo graphics library.
  32  *
  33  * The Initial Developer of the Original Code is University of Southern
  34  * California.
  35  *
  36  * Contributor(s):
  37  *      Carl D. Worth <cworth@cworth.org>
  38  *      Kristian Høgsberg <krh@redhat.com>
  39  *      Chris Wilson <chris@chris-wilson.co.uk>
  40  */
  41
  42 #include "cairoint.h"
  43 #include "cairo-clip-private.h"
  44 #include "cairo-error-private.h"
  45 #include "cairo-freed-pool-private.h"
  46 #include "cairo-gstate-private.h"
  47 #include "cairo-path-fixed-private.h"
  48 #include "cairo-pattern-private.h"
  49 #include "cairo-composite-rectangles-private.h"
  50 #include "cairo-region-private.h"
  51
  52 cairo_status_t
  53 _cairo_clip_combine_with_surface (const cairo_clip_t *clip,
  54                                   cairo_surface_t *dst,
  55                                   int dst_x, int dst_y)
  56 {
  57     cairo_clip_path_t *copy_path;
  58     cairo_clip_path_t *clip_path;
  59     cairo_clip_t *copy;
  60     cairo_status_t status = CAIRO_STATUS_SUCCESS;
  61
  62     copy = _cairo_clip_copy_with_translation (clip, -dst_x, -dst_y);
  63     copy_path = copy->path;
  64     copy->path = NULL;
  65
  66     if (copy->boxes) {
  67         status = _cairo_surface_paint (dst,
  68                                        CAIRO_OPERATOR_IN,
  69                                        &_cairo_pattern_white.base,
  70                                        copy);
  71     }
  72
  73     clip = NULL;
  74     if (_cairo_clip_is_region (copy))
  75         clip = copy;
  76     clip_path = copy_path;
  77     while (status == CAIRO_STATUS_SUCCESS && clip_path) {
  78         status = _cairo_surface_fill (dst,
  79                                       CAIRO_OPERATOR_IN,
  80                                       &_cairo_pattern_white.base,
  81                                       &clip_path->path,
  82                                       clip_path->fill_rule,
  83                                       clip_path->tolerance,
  84                                       clip_path->antialias,
  85                                       clip);
  86         clip_path = clip_path->prev;
  87     }
  88
  89     copy->path = copy_path;
  90     _cairo_clip_destroy (copy);
  91     return status;
  92 }
  93
  94 static cairo_status_t
  95 _cairo_path_fixed_add_box (cairo_path_fixed_t *path,
  96                            const cairo_box_t *box,
  97                            cairo_fixed_t fx,
  98                            cairo_fixed_t fy)
  99 {
 100     cairo_status_t status;
 101
 102     status = _cairo_path_fixed_move_to (path, box->p1.x + fx, box->p1.y + fy);
 103     if (unlikely (status))
 104         return status;
 105
 106     status = _cairo_path_fixed_line_to (path, box->p2.x + fx, box->p1.y + fy);
 107     if (unlikely (status))
 108         return status;
 109
 110     status = _cairo_path_fixed_line_to (path, box->p2.x + fx, box->p2.y + fy);
 111     if (unlikely (status))
 112         return status;
 113
 114     status = _cairo_path_fixed_line_to (path, box->p1.x + fx, box->p2.y + fy);
 115     if (unlikely (status))
 116         return status;
 117
 118     return _cairo_path_fixed_close_path (path);
 119 }
 120
 121 cairo_surface_t *
 122 _cairo_clip_get_surface (const cairo_clip_t *clip,
 123                          cairo_surface_t *target,
 124                          int *tx, int *ty)
 125 {
 126     cairo_surface_t *surface;
 127     cairo_status_t status;
 128     cairo_clip_t *copy, *region;
 129     cairo_clip_path_t *copy_path, *clip_path;
 130
 131     if (clip->num_boxes) {
 132         cairo_path_fixed_t path;
 133         int i;
 134
 135         surface = _cairo_surface_create_similar_solid (target,
 136                                                        CAIRO_CONTENT_ALPHA,
 137                                                        clip->extents.width,
 138                                                        clip->extents.height,
 139                                                        CAIRO_COLOR_TRANSPARENT);
 140         if (unlikely (surface->status))
 141             return surface;
 142
 143         _cairo_path_fixed_init (&path);
 144         status = CAIRO_STATUS_SUCCESS;
 145         for (i = 0; status == CAIRO_STATUS_SUCCESS && i < clip->num_boxes; i++) {
 146             status = _cairo_path_fixed_add_box (&path, &clip->boxes[i],
 147                                                 -_cairo_fixed_from_int (clip->extents.x),
 148                                                 -_cairo_fixed_from_int (clip->extents.y));
 149         }
 150         if (status == CAIRO_STATUS_SUCCESS)
 151             status = _cairo_surface_fill (surface,
 152                                           CAIRO_OPERATOR_ADD,
 153                                           &_cairo_pattern_white.base,
 154                                           &path,
 155                                           CAIRO_FILL_RULE_WINDING,
 156                                           1.,
 157                                           CAIRO_ANTIALIAS_DEFAULT,
 158                                           NULL);
 159         _cairo_path_fixed_fini (&path);
 160         if (unlikely (status)) {
 161             cairo_surface_destroy (surface);
 162             return _cairo_surface_create_in_error (status);
 163         }
 164     } else {
 165         surface = _cairo_surface_create_similar_solid (target,
 166                                                        CAIRO_CONTENT_ALPHA,
 167                                                        clip->extents.width,
 168                                                        clip->extents.height,
 169                                                        CAIRO_COLOR_WHITE);
 170         if (unlikely (surface->status))
 171             return surface;
 172     }
 173
 174     copy = _cairo_clip_copy_with_translation (clip,
 175                                               -clip->extents.x,
 176                                               -clip->extents.y);
 177     copy_path = copy->path;
 178     copy->path = NULL;
 179
 180     region = copy;
 181     if (! _cairo_clip_is_region (copy))
 182         region = _cairo_clip_copy_region (copy);
 183
 184     status = CAIRO_STATUS_SUCCESS;
 185     clip_path = copy_path;
 186     while (status == CAIRO_STATUS_SUCCESS && clip_path) {
 187         status = _cairo_surface_fill (surface,
 188                                       CAIRO_OPERATOR_IN,
 189                                       &_cairo_pattern_white.base,
 190                                       &clip_path->path,
 191                                       clip_path->fill_rule,
 192                                       clip_path->tolerance,
 193                                       clip_path->antialias,
 194                                       region);
 195         clip_path = clip_path->prev;
 196     }
 197
 198     copy->path = copy_path;
 199     _cairo_clip_destroy (copy);
 200     if (region != copy)
 201         _cairo_clip_destroy (region);
 202
 203     if (unlikely (status)) {
 204         cairo_surface_destroy (surface);
 205         return _cairo_surface_create_in_error (status);
 206     }
 207
 208     *tx = clip->extents.x;
 209     *ty = clip->extents.y;
 210     return surface;
 211 }
 212
 213 cairo_surface_t *
 214 _cairo_clip_get_image (const cairo_clip_t *clip,
 215                        cairo_surface_t *target,
 216                        const cairo_rectangle_int_t *extents)
 217 {
 218     cairo_surface_t *surface;
 219     cairo_status_t status;
 220
 221     surface = cairo_surface_create_similar_image (target,
 222                                                   CAIRO_FORMAT_A8,
 223                                                   extents->width,
 224                                                   extents->height);
 225     if (unlikely (surface->status))
 226         return surface;
 227
 228     status = _cairo_surface_paint (surface, CAIRO_OPERATOR_SOURCE,
 229                                    &_cairo_pattern_white.base, NULL);
 230     if (likely (status == CAIRO_STATUS_SUCCESS))
 231         status = _cairo_clip_combine_with_surface (clip, surface,
 232                                                    extents->x, extents->y);
 233
 234     if (unlikely (status)) {
 235         cairo_surface_destroy (surface);
 236         surface = _cairo_surface_create_in_error (status);
 237     }
 238
 239     return surface;
 240 }