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-rw-r--r--libs/cairo-1.16.0/src/cairo-path-in-fill.c290
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diff --git a/libs/cairo-1.16.0/src/cairo-path-in-fill.c b/libs/cairo-1.16.0/src/cairo-path-in-fill.c
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+++ b/libs/cairo-1.16.0/src/cairo-path-in-fill.c
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+/* cairo - a vector graphics library with display and print output
+ *
+ * Copyright © 2008 Chris Wilson
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it either under the terms of the GNU Lesser General Public
+ * License version 2.1 as published by the Free Software Foundation
+ * (the "LGPL") or, at your option, under the terms of the Mozilla
+ * Public License Version 1.1 (the "MPL"). If you do not alter this
+ * notice, a recipient may use your version of this file under either
+ * the MPL or the LGPL.
+ *
+ * You should have received a copy of the LGPL along with this library
+ * in the file COPYING-LGPL-2.1; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
+ * You should have received a copy of the MPL along with this library
+ * in the file COPYING-MPL-1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
+ * OF ANY KIND, either express or implied. See the LGPL or the MPL for
+ * the specific language governing rights and limitations.
+ *
+ * The Original Code is the cairo graphics library.
+ *
+ * The Initial Developer of the Original Code is Chris Wilson.
+ *
+ * Contributor(s):
+ * Chris Wilson <chris@chris-wilson.co.uk>
+ */
+
+#include "cairoint.h"
+#include "cairo-path-fixed-private.h"
+
+typedef struct cairo_in_fill {
+ double tolerance;
+ cairo_bool_t on_edge;
+ int winding;
+
+ cairo_fixed_t x, y;
+
+ cairo_bool_t has_current_point;
+ cairo_point_t current_point;
+ cairo_point_t first_point;
+} cairo_in_fill_t;
+
+static void
+_cairo_in_fill_init (cairo_in_fill_t *in_fill,
+ double tolerance,
+ double x,
+ double y)
+{
+ in_fill->on_edge = FALSE;
+ in_fill->winding = 0;
+ in_fill->tolerance = tolerance;
+
+ in_fill->x = _cairo_fixed_from_double (x);
+ in_fill->y = _cairo_fixed_from_double (y);
+
+ in_fill->has_current_point = FALSE;
+ in_fill->current_point.x = 0;
+ in_fill->current_point.y = 0;
+}
+
+static void
+_cairo_in_fill_fini (cairo_in_fill_t *in_fill)
+{
+}
+
+static int
+edge_compare_for_y_against_x (const cairo_point_t *p1,
+ const cairo_point_t *p2,
+ cairo_fixed_t y,
+ cairo_fixed_t x)
+{
+ cairo_fixed_t adx, ady;
+ cairo_fixed_t dx, dy;
+ cairo_int64_t L, R;
+
+ adx = p2->x - p1->x;
+ dx = x - p1->x;
+
+ if (adx == 0)
+ return -dx;
+ if ((adx ^ dx) < 0)
+ return adx;
+
+ dy = y - p1->y;
+ ady = p2->y - p1->y;
+
+ L = _cairo_int32x32_64_mul (dy, adx);
+ R = _cairo_int32x32_64_mul (dx, ady);
+
+ return _cairo_int64_cmp (L, R);
+}
+
+static void
+_cairo_in_fill_add_edge (cairo_in_fill_t *in_fill,
+ const cairo_point_t *p1,
+ const cairo_point_t *p2)
+{
+ int dir;
+
+ if (in_fill->on_edge)
+ return;
+
+ /* count the number of edge crossing to -∞ */
+
+ dir = 1;
+ if (p2->y < p1->y) {
+ const cairo_point_t *tmp;
+
+ tmp = p1;
+ p1 = p2;
+ p2 = tmp;
+
+ dir = -1;
+ }
+
+ /* First check whether the query is on an edge */
+ if ((p1->x == in_fill->x && p1->y == in_fill->y) ||
+ (p2->x == in_fill->x && p2->y == in_fill->y) ||
+ (! (p2->y < in_fill->y || p1->y > in_fill->y ||
+ (p1->x > in_fill->x && p2->x > in_fill->x) ||
+ (p1->x < in_fill->x && p2->x < in_fill->x)) &&
+ edge_compare_for_y_against_x (p1, p2, in_fill->y, in_fill->x) == 0))
+ {
+ in_fill->on_edge = TRUE;
+ return;
+ }
+
+ /* edge is entirely above or below, note the shortening rule */
+ if (p2->y <= in_fill->y || p1->y > in_fill->y)
+ return;
+
+ /* edge lies wholly to the right */
+ if (p1->x >= in_fill->x && p2->x >= in_fill->x)
+ return;
+
+ if ((p1->x <= in_fill->x && p2->x <= in_fill->x) ||
+ edge_compare_for_y_against_x (p1, p2, in_fill->y, in_fill->x) < 0)
+ {
+ in_fill->winding += dir;
+ }
+}
+
+static cairo_status_t
+_cairo_in_fill_move_to (void *closure,
+ const cairo_point_t *point)
+{
+ cairo_in_fill_t *in_fill = closure;
+
+ /* implicit close path */
+ if (in_fill->has_current_point) {
+ _cairo_in_fill_add_edge (in_fill,
+ &in_fill->current_point,
+ &in_fill->first_point);
+ }
+
+ in_fill->first_point = *point;
+ in_fill->current_point = *point;
+ in_fill->has_current_point = TRUE;
+
+ return CAIRO_STATUS_SUCCESS;
+}
+
+static cairo_status_t
+_cairo_in_fill_line_to (void *closure,
+ const cairo_point_t *point)
+{
+ cairo_in_fill_t *in_fill = closure;
+
+ if (in_fill->has_current_point)
+ _cairo_in_fill_add_edge (in_fill, &in_fill->current_point, point);
+
+ in_fill->current_point = *point;
+ in_fill->has_current_point = TRUE;
+
+ return CAIRO_STATUS_SUCCESS;
+}
+
+static cairo_status_t
+_cairo_in_fill_curve_to (void *closure,
+ const cairo_point_t *b,
+ const cairo_point_t *c,
+ const cairo_point_t *d)
+{
+ cairo_in_fill_t *in_fill = closure;
+ cairo_spline_t spline;
+ cairo_fixed_t top, bot, left;
+
+ /* first reject based on bbox */
+ bot = top = in_fill->current_point.y;
+ if (b->y < top) top = b->y;
+ if (b->y > bot) bot = b->y;
+ if (c->y < top) top = c->y;
+ if (c->y > bot) bot = c->y;
+ if (d->y < top) top = d->y;
+ if (d->y > bot) bot = d->y;
+ if (bot < in_fill->y || top > in_fill->y) {
+ in_fill->current_point = *d;
+ return CAIRO_STATUS_SUCCESS;
+ }
+
+ left = in_fill->current_point.x;
+ if (b->x < left) left = b->x;
+ if (c->x < left) left = c->x;
+ if (d->x < left) left = d->x;
+ if (left > in_fill->x) {
+ in_fill->current_point = *d;
+ return CAIRO_STATUS_SUCCESS;
+ }
+
+ /* XXX Investigate direct inspection of the inflections? */
+ if (! _cairo_spline_init (&spline,
+ (cairo_spline_add_point_func_t)_cairo_in_fill_line_to,
+ in_fill,
+ &in_fill->current_point, b, c, d))
+ {
+ return CAIRO_STATUS_SUCCESS;
+ }
+
+ return _cairo_spline_decompose (&spline, in_fill->tolerance);
+}
+
+static cairo_status_t
+_cairo_in_fill_close_path (void *closure)
+{
+ cairo_in_fill_t *in_fill = closure;
+
+ if (in_fill->has_current_point) {
+ _cairo_in_fill_add_edge (in_fill,
+ &in_fill->current_point,
+ &in_fill->first_point);
+
+ in_fill->has_current_point = FALSE;
+ }
+
+ return CAIRO_STATUS_SUCCESS;
+}
+
+cairo_bool_t
+_cairo_path_fixed_in_fill (const cairo_path_fixed_t *path,
+ cairo_fill_rule_t fill_rule,
+ double tolerance,
+ double x,
+ double y)
+{
+ cairo_in_fill_t in_fill;
+ cairo_status_t status;
+ cairo_bool_t is_inside;
+
+ if (_cairo_path_fixed_fill_is_empty (path))
+ return FALSE;
+
+ _cairo_in_fill_init (&in_fill, tolerance, x, y);
+
+ status = _cairo_path_fixed_interpret (path,
+ _cairo_in_fill_move_to,
+ _cairo_in_fill_line_to,
+ _cairo_in_fill_curve_to,
+ _cairo_in_fill_close_path,
+ &in_fill);
+ assert (status == CAIRO_STATUS_SUCCESS);
+
+ _cairo_in_fill_close_path (&in_fill);
+
+ if (in_fill.on_edge) {
+ is_inside = TRUE;
+ } else switch (fill_rule) {
+ case CAIRO_FILL_RULE_EVEN_ODD:
+ is_inside = in_fill.winding & 1;
+ break;
+ case CAIRO_FILL_RULE_WINDING:
+ is_inside = in_fill.winding != 0;
+ break;
+ default:
+ ASSERT_NOT_REACHED;
+ is_inside = FALSE;
+ break;
+ }
+
+ _cairo_in_fill_fini (&in_fill);
+
+ return is_inside;
+}
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