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     if (copy == NULL)
  64         return CAIRO_STATUS_NULL_POINTER;
  65     copy_path = copy->path;
  66     copy->path = NULL;
  67
  68     if (copy->boxes) {
  69         status = _cairo_surface_paint (dst,
  70                                        CAIRO_OPERATOR_IN,
  71                                        &_cairo_pattern_white.base,
  72                                        copy);
  73     }
  74
  75     clip = NULL;
  76     if (_cairo_clip_is_region (copy))
  77         clip = copy;
  78     clip_path = copy_path;
  79     while (status == CAIRO_STATUS_SUCCESS && clip_path) {
  80         status = _cairo_surface_fill (dst,
  81                                       CAIRO_OPERATOR_IN,
  82                                       &_cairo_pattern_white.base,
  83                                       &clip_path->path,
  84                                       clip_path->fill_rule,
  85                                       clip_path->tolerance,
  86                                       clip_path->antialias,
  87                                       clip);
  88         clip_path = clip_path->prev;
  89     }
  90
  91     copy->path = copy_path;
  92     _cairo_clip_destroy (copy);
  93     return status;
  94 }
  95
  96 static cairo_status_t
  97 _cairo_path_fixed_add_box (cairo_path_fixed_t *path,
  98                            const cairo_box_t *box,
  99                            cairo_fixed_t fx,
 100                            cairo_fixed_t fy)
 101 {
 102     cairo_status_t status;
 103
 104     status = _cairo_path_fixed_move_to (path, box->p1.x + fx, box->p1.y + fy);
 105     if (unlikely (status))
 106         return status;
 107
 108     status = _cairo_path_fixed_line_to (path, box->p2.x + fx, box->p1.y + fy);
 109     if (unlikely (status))
 110         return status;
 111
 112     status = _cairo_path_fixed_line_to (path, box->p2.x + fx, box->p2.y + fy);
 113     if (unlikely (status))
 114         return status;
 115
 116     status = _cairo_path_fixed_line_to (path, box->p1.x + fx, box->p2.y + fy);
 117     if (unlikely (status))
 118         return status;
 119
 120     return _cairo_path_fixed_close_path (path);
 121 }
 122
 123 cairo_surface_t *
 124 _cairo_clip_get_surface (const cairo_clip_t *clip,
 125                          cairo_surface_t *target,
 126                          int *tx, int *ty)
 127 {
 128     cairo_surface_t *surface;
 129     cairo_status_t status;
 130     cairo_clip_t *copy, *region;
 131     cairo_clip_path_t *copy_path, *clip_path;
 132
 133     if (clip->num_boxes) {
 134         cairo_path_fixed_t path;
 135         int i;
 136
 137         surface = _cairo_surface_create_similar_solid (target,
 138                                                        CAIRO_CONTENT_ALPHA,
 139                                                        clip->extents.width,
 140                                                        clip->extents.height,
 141                                                        CAIRO_COLOR_TRANSPARENT);
 142         if (unlikely (surface->status))
 143             return surface;
 144
 145         _cairo_path_fixed_init (&path);
 146         status = CAIRO_STATUS_SUCCESS;
 147         for (i = 0; status == CAIRO_STATUS_SUCCESS && i < clip->num_boxes; i++) {
 148             status = _cairo_path_fixed_add_box (&path, &clip->boxes[i],
 149                                                 -_cairo_fixed_from_int (clip->extents.x),
 150                                                 -_cairo_fixed_from_int (clip->extents.y));
 151         }
 152         if (status == CAIRO_STATUS_SUCCESS)
 153             status = _cairo_surface_fill (surface,
 154                                           CAIRO_OPERATOR_ADD,
 155                                           &_cairo_pattern_white.base,
 156                                           &path,
 157                                           CAIRO_FILL_RULE_WINDING,
 158                                           1.,
 159                                           CAIRO_ANTIALIAS_DEFAULT,
 160                                           NULL);
 161         _cairo_path_fixed_fini (&path);
 162         if (unlikely (status)) {
 163             cairo_surface_destroy (surface);
 164             return _cairo_surface_create_in_error (status);
 165         }
 166     } else {
 167         surface = _cairo_surface_create_similar_solid (target,
 168                                                        CAIRO_CONTENT_ALPHA,
 169                                                        clip->extents.width,
 170                                                        clip->extents.height,
 171                                                        CAIRO_COLOR_WHITE);
 172         if (unlikely (surface->status))
 173             return surface;
 174     }
 175
 176     copy = _cairo_clip_copy_with_translation (clip,
 177                                               -clip->extents.x,
 178                                               -clip->extents.y);
 179     if (copy == NULL) {
 180         cairo_surface_destroy (surface);
 181         status = CAIRO_STATUS_NULL_POINTER;
 182         return _cairo_surface_create_in_error (status);
 183     }
 184     copy_path = copy->path;
 185     copy->path = NULL;
 186
 187     region = copy;
 188     if (! _cairo_clip_is_region (copy))
 189         region = _cairo_clip_copy_region (copy);
 190
 191     status = CAIRO_STATUS_SUCCESS;
 192     clip_path = copy_path;
 193     while (status == CAIRO_STATUS_SUCCESS && clip_path) {
 194         status = _cairo_surface_fill (surface,
 195                                       CAIRO_OPERATOR_IN,
 196                                       &_cairo_pattern_white.base,
 197                                       &clip_path->path,
 198                                       clip_path->fill_rule,
 199                                       clip_path->tolerance,
 200                                       clip_path->antialias,
 201                                       region);
 202         clip_path = clip_path->prev;
 203     }
 204
 205     copy->path = copy_path;
 206     _cairo_clip_destroy (copy);
 207     if (region != copy)
 208         _cairo_clip_destroy (region);
 209
 210     if (unlikely (status)) {
 211         cairo_surface_destroy (surface);
 212         return _cairo_surface_create_in_error (status);
 213     }
 214
 215     *tx = clip->extents.x;
 216     *ty = clip->extents.y;
 217     return surface;
 218 }
 219
 220 cairo_surface_t *
 221 _cairo_clip_get_image (const cairo_clip_t *clip,
 222                        cairo_surface_t *target,
 223                        const cairo_rectangle_int_t *extents)
 224 {
 225     cairo_surface_t *surface;
 226     cairo_status_t status;
 227
 228     surface = cairo_surface_create_similar_image (target,
 229                                                   CAIRO_FORMAT_A8,
 230                                                   extents->width,
 231                                                   extents->height);
 232     if (unlikely (surface->status))
 233         return surface;
 234
 235     status = _cairo_surface_paint (surface, CAIRO_OPERATOR_SOURCE,
 236                                    &_cairo_pattern_white.base, NULL);
 237     if (likely (status == CAIRO_STATUS_SUCCESS))
 238         status = _cairo_clip_combine_with_surface (clip, surface,
 239                                                    extents->x, extents->y);
 240
 241     if (unlikely (status)) {
 242         cairo_surface_destroy (surface);
 243         surface = _cairo_surface_create_in_error (status);
 244     }
 245
 246     return surface;
 247 }