blob: bb4972f5003403cb5ae708248790910b78f9f8f7 [file] [log] [blame]
/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */
/*
* Copyright © 2011 Intel Corporation
*
* 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-wilsonc.co.uk>
*/
#include "cairoint.h"
#include "cairo-error-private.h"
#include "cairo-tristrip-private.h"
void
_cairo_tristrip_init (cairo_tristrip_t *strip)
{
VG (VALGRIND_MAKE_MEM_UNDEFINED (strip, sizeof (cairo_tristrip_t)));
strip->status = CAIRO_STATUS_SUCCESS;
strip->num_limits = 0;
strip->num_points = 0;
strip->size_points = ARRAY_LENGTH (strip->points_embedded);
strip->points = strip->points_embedded;
}
void
_cairo_tristrip_fini (cairo_tristrip_t *strip)
{
if (strip->points != strip->points_embedded)
free (strip->points);
VG (VALGRIND_MAKE_MEM_NOACCESS (strip, sizeof (cairo_tristrip_t)));
}
void
_cairo_tristrip_limit (cairo_tristrip_t *strip,
const cairo_box_t *limits,
int num_limits)
{
strip->limits = limits;
strip->num_limits = num_limits;
}
void
_cairo_tristrip_init_with_clip (cairo_tristrip_t *strip,
const cairo_clip_t *clip)
{
_cairo_tristrip_init (strip);
if (clip)
_cairo_tristrip_limit (strip, clip->boxes, clip->num_boxes);
}
/* make room for at least one more trap */
static cairo_bool_t
_cairo_tristrip_grow (cairo_tristrip_t *strip)
{
cairo_point_t *points;
int new_size = 4 * strip->size_points;
if (CAIRO_INJECT_FAULT ()) {
strip->status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
return FALSE;
}
if (strip->points == strip->points_embedded) {
points = _cairo_malloc_ab (new_size, sizeof (cairo_point_t));
if (points != NULL)
memcpy (points, strip->points, sizeof (strip->points_embedded));
} else {
points = _cairo_realloc_ab (strip->points,
new_size, sizeof (cairo_trapezoid_t));
}
if (unlikely (points == NULL)) {
strip->status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
return FALSE;
}
strip->points = points;
strip->size_points = new_size;
return TRUE;
}
void
_cairo_tristrip_add_point (cairo_tristrip_t *strip,
const cairo_point_t *p)
{
if (unlikely (strip->num_points == strip->size_points)) {
if (unlikely (! _cairo_tristrip_grow (strip)))
return;
}
strip->points[strip->num_points++] = *p;
}
/* Insert degenerate triangles to advance to the given point. The
* next point inserted must also be @p. */
void
_cairo_tristrip_move_to (cairo_tristrip_t *strip,
const cairo_point_t *p)
{
if (strip->num_points == 0)
return;
_cairo_tristrip_add_point (strip, &strip->points[strip->num_points-1]);
_cairo_tristrip_add_point (strip, p);
#if 0
/* and one more for luck! (to preserve cw/ccw ordering) */
_cairo_tristrip_add_point (strip, p);
#endif
}
void
_cairo_tristrip_translate (cairo_tristrip_t *strip, int x, int y)
{
cairo_fixed_t xoff, yoff;
cairo_point_t *p;
int i;
xoff = _cairo_fixed_from_int (x);
yoff = _cairo_fixed_from_int (y);
for (i = 0, p = strip->points; i < strip->num_points; i++, p++) {
p->x += xoff;
p->y += yoff;
}
}
void
_cairo_tristrip_extents (const cairo_tristrip_t *strip,
cairo_box_t *extents)
{
int i;
if (strip->num_points == 0) {
extents->p1.x = extents->p1.y = 0;
extents->p2.x = extents->p2.y = 0;
return;
}
extents->p2 = extents->p1 = strip->points[0];
for (i = 1; i < strip->num_points; i++) {
const cairo_point_t *p = &strip->points[i];
if (p->x < extents->p1.x)
extents->p1.x = p->x;
else if (p->x > extents->p2.x)
extents->p2.x = p->x;
if (p->y < extents->p1.y)
extents->p1.y = p->y;
else if (p->y > extents->p2.y)
extents->p2.y = p->y;
}
}