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/* cairo - a vector graphics library with display and print output
*
* Copyright © 2009 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
*
* 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.
*
* Contributor(s):
* Chris Wilson <chris@chris-wilson.co.uk>
*/
#include "cairoint.h"
#include "cairo-box-inline.h"
#include "cairo-boxes-private.h"
#include "cairo-error-private.h"
void
_cairo_boxes_init (cairo_boxes_t *boxes)
{
boxes->status = CAIRO_STATUS_SUCCESS;
boxes->num_limits = 0;
boxes->num_boxes = 0;
boxes->tail = &boxes->chunks;
boxes->chunks.next = NULL;
boxes->chunks.base = boxes->boxes_embedded;
boxes->chunks.size = ARRAY_LENGTH (boxes->boxes_embedded);
boxes->chunks.count = 0;
boxes->is_pixel_aligned = TRUE;
}
void
_cairo_boxes_init_from_rectangle (cairo_boxes_t *boxes,
int x, int y, int w, int h)
{
_cairo_boxes_init (boxes);
_cairo_box_from_integers (&boxes->chunks.base[0], x, y, w, h);
boxes->num_boxes = 1;
}
void
_cairo_boxes_init_with_clip (cairo_boxes_t *boxes,
cairo_clip_t *clip)
{
_cairo_boxes_init (boxes);
if (clip)
_cairo_boxes_limit (boxes, clip->boxes, clip->num_boxes);
}
void
_cairo_boxes_init_for_array (cairo_boxes_t *boxes,
cairo_box_t *array,
int num_boxes)
{
int n;
boxes->status = CAIRO_STATUS_SUCCESS;
boxes->num_limits = 0;
boxes->num_boxes = num_boxes;
boxes->tail = &boxes->chunks;
boxes->chunks.next = NULL;
boxes->chunks.base = array;
boxes->chunks.size = num_boxes;
boxes->chunks.count = num_boxes;
for (n = 0; n < num_boxes; n++) {
if (! _cairo_fixed_is_integer (array[n].p1.x) ||
! _cairo_fixed_is_integer (array[n].p1.y) ||
! _cairo_fixed_is_integer (array[n].p2.x) ||
! _cairo_fixed_is_integer (array[n].p2.y))
{
break;
}
}
boxes->is_pixel_aligned = n == num_boxes;
}
/**
* _cairo_boxes_limit:
* @boxes: the box set to be filled (return buffer)
* @limits: array of the limiting boxes to compute the bounding
* box from
* @num_limits: length of the limits array
*
* Computes the minimum bounding box of the given list of boxes and assign
* it to the given boxes set. It also assigns that list as the list of
* limiting boxes in the box set.
*/
void
_cairo_boxes_limit (cairo_boxes_t *boxes,
const cairo_box_t *limits,
int num_limits)
{
int n;
boxes->limits = limits;
boxes->num_limits = num_limits;
if (boxes->num_limits) {
boxes->limit = limits[0];
for (n = 1; n < num_limits; n++) {
if (limits[n].p1.x < boxes->limit.p1.x)
boxes->limit.p1.x = limits[n].p1.x;
if (limits[n].p1.y < boxes->limit.p1.y)
boxes->limit.p1.y = limits[n].p1.y;
if (limits[n].p2.x > boxes->limit.p2.x)
boxes->limit.p2.x = limits[n].p2.x;
if (limits[n].p2.y > boxes->limit.p2.y)
boxes->limit.p2.y = limits[n].p2.y;
}
}
}
static void
_cairo_boxes_add_internal (cairo_boxes_t *boxes,
const cairo_box_t *box)
{
struct _cairo_boxes_chunk *chunk;
if (unlikely (boxes->status))
return;
chunk = boxes->tail;
if (unlikely (chunk->count == chunk->size)) {
int size;
size = chunk->size * 2;
chunk->next = _cairo_malloc_ab_plus_c (size,
sizeof (cairo_box_t),
sizeof (struct _cairo_boxes_chunk));
if (unlikely (chunk->next == NULL)) {
boxes->status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
return;
}
chunk = chunk->next;
boxes->tail = chunk;
chunk->next = NULL;
chunk->count = 0;
chunk->size = size;
chunk->base = (cairo_box_t *) (chunk + 1);
}
chunk->base[chunk->count++] = *box;
boxes->num_boxes++;
if (boxes->is_pixel_aligned)
boxes->is_pixel_aligned = _cairo_box_is_pixel_aligned (box);
}
cairo_status_t
_cairo_boxes_add (cairo_boxes_t *boxes,
cairo_antialias_t antialias,
const cairo_box_t *box)
{
cairo_box_t b;
if (antialias == CAIRO_ANTIALIAS_NONE) {
b.p1.x = _cairo_fixed_round_down (box->p1.x);
b.p1.y = _cairo_fixed_round_down (box->p1.y);
b.p2.x = _cairo_fixed_round_down (box->p2.x);
b.p2.y = _cairo_fixed_round_down (box->p2.y);
box = &b;
}
if (box->p1.y == box->p2.y)
return CAIRO_STATUS_SUCCESS;
if (box->p1.x == box->p2.x)
return CAIRO_STATUS_SUCCESS;
if (boxes->num_limits) {
cairo_point_t p1, p2;
cairo_bool_t reversed = FALSE;
int n;
/* support counter-clockwise winding for rectangular tessellation */
if (box->p1.x < box->p2.x) {
p1.x = box->p1.x;
p2.x = box->p2.x;
} else {
p2.x = box->p1.x;
p1.x = box->p2.x;
reversed = ! reversed;
}
if (p1.x >= boxes->limit.p2.x || p2.x <= boxes->limit.p1.x)
return CAIRO_STATUS_SUCCESS;
if (box->p1.y < box->p2.y) {
p1.y = box->p1.y;
p2.y = box->p2.y;
} else {
p2.y = box->p1.y;
p1.y = box->p2.y;
reversed = ! reversed;
}
if (p1.y >= boxes->limit.p2.y || p2.y <= boxes->limit.p1.y)
return CAIRO_STATUS_SUCCESS;
for (n = 0; n < boxes->num_limits; n++) {
const cairo_box_t *limits = &boxes->limits[n];
cairo_box_t _box;
cairo_point_t _p1, _p2;
if (p1.x >= limits->p2.x || p2.x <= limits->p1.x)
continue;
if (p1.y >= limits->p2.y || p2.y <= limits->p1.y)
continue;
/* Otherwise, clip the box to the limits. */
_p1 = p1;
if (_p1.x < limits->p1.x)
_p1.x = limits->p1.x;
if (_p1.y < limits->p1.y)
_p1.y = limits->p1.y;
_p2 = p2;
if (_p2.x > limits->p2.x)
_p2.x = limits->p2.x;
if (_p2.y > limits->p2.y)
_p2.y = limits->p2.y;
if (_p2.y <= _p1.y || _p2.x <= _p1.x)
continue;
_box.p1.y = _p1.y;
_box.p2.y = _p2.y;
if (reversed) {
_box.p1.x = _p2.x;
_box.p2.x = _p1.x;
} else {
_box.p1.x = _p1.x;
_box.p2.x = _p2.x;
}
_cairo_boxes_add_internal (boxes, &_box);
}
} else {
_cairo_boxes_add_internal (boxes, box);
}
return boxes->status;
}
/**
* _cairo_boxes_extents:
* @boxes: The box set whose minimum bounding is computed.
* @box: Return buffer for the computed result.
*
* Computes the minimum bounding box of the given box set and stores
* it in the given box.
*/
void
_cairo_boxes_extents (const cairo_boxes_t *boxes,
cairo_box_t *box)
{
const struct _cairo_boxes_chunk *chunk;
cairo_box_t b;
int i;
if (boxes->num_boxes == 0) {
box->p1.x = box->p1.y = box->p2.x = box->p2.y = 0;
return;
}
b = boxes->chunks.base[0];
for (chunk = &boxes->chunks; chunk != NULL; chunk = chunk->next) {
for (i = 0; i < chunk->count; i++) {
if (chunk->base[i].p1.x < b.p1.x)
b.p1.x = chunk->base[i].p1.x;
if (chunk->base[i].p1.y < b.p1.y)
b.p1.y = chunk->base[i].p1.y;
if (chunk->base[i].p2.x > b.p2.x)
b.p2.x = chunk->base[i].p2.x;
if (chunk->base[i].p2.y > b.p2.y)
b.p2.y = chunk->base[i].p2.y;
}
}
*box = b;
}
void
_cairo_boxes_clear (cairo_boxes_t *boxes)
{
struct _cairo_boxes_chunk *chunk, *next;
for (chunk = boxes->chunks.next; chunk != NULL; chunk = next) {
next = chunk->next;
free (chunk);
}
boxes->tail = &boxes->chunks;
boxes->chunks.next = 0;
boxes->chunks.count = 0;
boxes->chunks.base = boxes->boxes_embedded;
boxes->chunks.size = ARRAY_LENGTH (boxes->boxes_embedded);
boxes->num_boxes = 0;
boxes->is_pixel_aligned = TRUE;
}
/**
* _cairo_boxes_to_array:
* @boxes The box set to be converted.
* @num_boxes Return buffer for the number of boxes (array count).
*
* Linearize a box set of possibly multiple chunks into one big chunk
* and returns an array of boxes
*
* Return value: Pointer to the newly allocated array of boxes (the number o
* elements is given in num_boxes).
*/
cairo_box_t *
_cairo_boxes_to_array (const cairo_boxes_t *boxes,
int *num_boxes)
{
const struct _cairo_boxes_chunk *chunk;
cairo_box_t *box;
int i, j;
*num_boxes = boxes->num_boxes;
box = _cairo_malloc_ab (boxes->num_boxes, sizeof (cairo_box_t));
if (box == NULL) {
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return NULL;
}
j = 0;
for (chunk = &boxes->chunks; chunk != NULL; chunk = chunk->next) {
for (i = 0; i < chunk->count; i++)
box[j++] = chunk->base[i];
}
return box;
}
void
_cairo_boxes_fini (cairo_boxes_t *boxes)
{
struct _cairo_boxes_chunk *chunk, *next;
for (chunk = boxes->chunks.next; chunk != NULL; chunk = next) {
next = chunk->next;
free (chunk);
}
}
cairo_bool_t
_cairo_boxes_for_each_box (cairo_boxes_t *boxes,
cairo_bool_t (*func) (cairo_box_t *box, void *data),
void *data)
{
struct _cairo_boxes_chunk *chunk;
int i;
for (chunk = &boxes->chunks; chunk != NULL; chunk = chunk->next) {
for (i = 0; i < chunk->count; i++)
if (! func (&chunk->base[i], data))
return FALSE;
}
return TRUE;
}
struct cairo_box_renderer {
cairo_span_renderer_t base;
cairo_boxes_t *boxes;
};
static cairo_status_t
span_to_boxes (void *abstract_renderer, int y, int h,
const cairo_half_open_span_t *spans, unsigned num_spans)
{
struct cairo_box_renderer *r = abstract_renderer;
cairo_status_t status = CAIRO_STATUS_SUCCESS;
cairo_box_t box;
if (num_spans == 0)
return CAIRO_STATUS_SUCCESS;
box.p1.y = _cairo_fixed_from_int (y);
box.p2.y = _cairo_fixed_from_int (y + h);
do {
if (spans[0].coverage) {
box.p1.x = _cairo_fixed_from_int(spans[0].x);
box.p2.x = _cairo_fixed_from_int(spans[1].x);
status = _cairo_boxes_add (r->boxes, CAIRO_ANTIALIAS_DEFAULT, &box);
}
spans++;
} while (--num_spans > 1 && status == CAIRO_STATUS_SUCCESS);
return status;
}
cairo_status_t
_cairo_rasterise_polygon_to_boxes (cairo_polygon_t *polygon,
cairo_fill_rule_t fill_rule,
cairo_boxes_t *boxes)
{
struct cairo_box_renderer renderer;
cairo_scan_converter_t *converter;
cairo_int_status_t status;
cairo_rectangle_int_t r;
TRACE ((stderr, "%s: fill_rule=%d\n", __FUNCTION__, fill_rule));
_cairo_box_round_to_rectangle (&polygon->extents, &r);
converter = _cairo_mono_scan_converter_create (r.x, r.y,
r.x + r.width,
r.y + r.height,
fill_rule);
status = _cairo_mono_scan_converter_add_polygon (converter, polygon);
if (unlikely (status))
goto cleanup_converter;
renderer.boxes = boxes;
renderer.base.render_rows = span_to_boxes;
status = converter->generate (converter, &renderer.base);
cleanup_converter:
converter->destroy (converter);
return status;
}
void
_cairo_debug_print_boxes (FILE *stream, const cairo_boxes_t *boxes)
{
const struct _cairo_boxes_chunk *chunk;
cairo_box_t extents;
int i;
_cairo_boxes_extents (boxes, &extents);
fprintf (stream, "boxes x %d: (%f, %f) x (%f, %f)\n",
boxes->num_boxes,
_cairo_fixed_to_double (extents.p1.x),
_cairo_fixed_to_double (extents.p1.y),
_cairo_fixed_to_double (extents.p2.x),
_cairo_fixed_to_double (extents.p2.y));
for (chunk = &boxes->chunks; chunk != NULL; chunk = chunk->next) {
for (i = 0; i < chunk->count; i++) {
fprintf (stderr, " box[%d]: (%f, %f), (%f, %f)\n", i,
_cairo_fixed_to_double (chunk->base[i].p1.x),
_cairo_fixed_to_double (chunk->base[i].p1.y),
_cairo_fixed_to_double (chunk->base[i].p2.x),
_cairo_fixed_to_double (chunk->base[i].p2.y));
}
}
}