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/* cairo - a vector graphics library with display and print output
*
* Copyright © 2005 Red Hat, Inc.
* Copyright © 2006 Red Hat, Inc.
*
* 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.
*
* The Initial Developer of the Original Code is Red Hat, Inc.
*
* Contributor(s):
* Carl D. Worth <cworth@redhat.com>
*/
#include "cairoint.h"
#include "cairo-private.h"
#include "cairo-backend-private.h"
#include "cairo-error-private.h"
#include "cairo-path-private.h"
#include "cairo-path-fixed-private.h"
/**
* SECTION:cairo-paths
* @Title: Paths
* @Short_Description: Creating paths and manipulating path data
*
* Paths are the most basic drawing tools and are primarily used to implicitly
* generate simple masks.
**/
static const cairo_path_t _cairo_path_nil = { CAIRO_STATUS_NO_MEMORY, NULL, 0 };
/* Closure for path interpretation. */
typedef struct cairo_path_count {
int count;
} cpc_t;
static cairo_status_t
_cpc_move_to (void *closure,
const cairo_point_t *point)
{
cpc_t *cpc = closure;
cpc->count += 2;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cpc_line_to (void *closure,
const cairo_point_t *point)
{
cpc_t *cpc = closure;
cpc->count += 2;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cpc_curve_to (void *closure,
const cairo_point_t *p1,
const cairo_point_t *p2,
const cairo_point_t *p3)
{
cpc_t *cpc = closure;
cpc->count += 4;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cpc_close_path (void *closure)
{
cpc_t *cpc = closure;
cpc->count += 1;
return CAIRO_STATUS_SUCCESS;
}
static int
_cairo_path_count (cairo_path_t *path,
cairo_path_fixed_t *path_fixed,
double tolerance,
cairo_bool_t flatten)
{
cairo_status_t status;
cpc_t cpc;
cpc.count = 0;
if (flatten) {
status = _cairo_path_fixed_interpret_flat (path_fixed,
_cpc_move_to,
_cpc_line_to,
_cpc_close_path,
&cpc,
tolerance);
} else {
status = _cairo_path_fixed_interpret (path_fixed,
_cpc_move_to,
_cpc_line_to,
_cpc_curve_to,
_cpc_close_path,
&cpc);
}
if (unlikely (status))
return -1;
return cpc.count;
}
/* Closure for path interpretation. */
typedef struct cairo_path_populate {
cairo_path_data_t *data;
cairo_t *cr;
} cpp_t;
static cairo_status_t
_cpp_move_to (void *closure,
const cairo_point_t *point)
{
cpp_t *cpp = closure;
cairo_path_data_t *data = cpp->data;
double x, y;
x = _cairo_fixed_to_double (point->x);
y = _cairo_fixed_to_double (point->y);
_cairo_backend_to_user (cpp->cr, &x, &y);
data->header.type = CAIRO_PATH_MOVE_TO;
data->header.length = 2;
/* We index from 1 to leave room for data->header */
data[1].point.x = x;
data[1].point.y = y;
cpp->data += data->header.length;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cpp_line_to (void *closure,
const cairo_point_t *point)
{
cpp_t *cpp = closure;
cairo_path_data_t *data = cpp->data;
double x, y;
x = _cairo_fixed_to_double (point->x);
y = _cairo_fixed_to_double (point->y);
_cairo_backend_to_user (cpp->cr, &x, &y);
data->header.type = CAIRO_PATH_LINE_TO;
data->header.length = 2;
/* We index from 1 to leave room for data->header */
data[1].point.x = x;
data[1].point.y = y;
cpp->data += data->header.length;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cpp_curve_to (void *closure,
const cairo_point_t *p1,
const cairo_point_t *p2,
const cairo_point_t *p3)
{
cpp_t *cpp = closure;
cairo_path_data_t *data = cpp->data;
double x1, y1;
double x2, y2;
double x3, y3;
x1 = _cairo_fixed_to_double (p1->x);
y1 = _cairo_fixed_to_double (p1->y);
_cairo_backend_to_user (cpp->cr, &x1, &y1);
x2 = _cairo_fixed_to_double (p2->x);
y2 = _cairo_fixed_to_double (p2->y);
_cairo_backend_to_user (cpp->cr, &x2, &y2);
x3 = _cairo_fixed_to_double (p3->x);
y3 = _cairo_fixed_to_double (p3->y);
_cairo_backend_to_user (cpp->cr, &x3, &y3);
data->header.type = CAIRO_PATH_CURVE_TO;
data->header.length = 4;
/* We index from 1 to leave room for data->header */
data[1].point.x = x1;
data[1].point.y = y1;
data[2].point.x = x2;
data[2].point.y = y2;
data[3].point.x = x3;
data[3].point.y = y3;
cpp->data += data->header.length;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cpp_close_path (void *closure)
{
cpp_t *cpp = closure;
cairo_path_data_t *data = cpp->data;
data->header.type = CAIRO_PATH_CLOSE_PATH;
data->header.length = 1;
cpp->data += data->header.length;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cairo_path_populate (cairo_path_t *path,
cairo_path_fixed_t *path_fixed,
cairo_t *cr,
cairo_bool_t flatten)
{
cairo_status_t status;
cpp_t cpp;
cpp.data = path->data;
cpp.cr = cr;
if (flatten) {
status = _cairo_path_fixed_interpret_flat (path_fixed,
_cpp_move_to,
_cpp_line_to,
_cpp_close_path,
&cpp,
cairo_get_tolerance (cr));
} else {
status = _cairo_path_fixed_interpret (path_fixed,
_cpp_move_to,
_cpp_line_to,
_cpp_curve_to,
_cpp_close_path,
&cpp);
}
if (unlikely (status))
return status;
/* Sanity check the count */
assert (cpp.data - path->data == path->num_data);
return CAIRO_STATUS_SUCCESS;
}
cairo_path_t *
_cairo_path_create_in_error (cairo_status_t status)
{
cairo_path_t *path;
/* special case NO_MEMORY so as to avoid allocations */
if (status == CAIRO_STATUS_NO_MEMORY)
return (cairo_path_t*) &_cairo_path_nil;
path = _cairo_malloc (sizeof (cairo_path_t));
if (unlikely (path == NULL)) {
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return (cairo_path_t*) &_cairo_path_nil;
}
path->num_data = 0;
path->data = NULL;
path->status = status;
return path;
}
static cairo_path_t *
_cairo_path_create_internal (cairo_path_fixed_t *path_fixed,
cairo_t *cr,
cairo_bool_t flatten)
{
cairo_path_t *path;
path = _cairo_malloc (sizeof (cairo_path_t));
if (unlikely (path == NULL)) {
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return (cairo_path_t*) &_cairo_path_nil;
}
path->num_data = _cairo_path_count (path, path_fixed,
cairo_get_tolerance (cr),
flatten);
if (path->num_data < 0) {
free (path);
return (cairo_path_t*) &_cairo_path_nil;
}
if (path->num_data) {
path->data = _cairo_malloc_ab (path->num_data,
sizeof (cairo_path_data_t));
if (unlikely (path->data == NULL)) {
free (path);
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return (cairo_path_t*) &_cairo_path_nil;
}
path->status = _cairo_path_populate (path, path_fixed, cr, flatten);
} else {
path->data = NULL;
path->status = CAIRO_STATUS_SUCCESS;
}
return path;
}
/**
* cairo_path_destroy:
* @path: a path previously returned by either cairo_copy_path() or
* cairo_copy_path_flat().
*
* Immediately releases all memory associated with @path. After a call
* to cairo_path_destroy() the @path pointer is no longer valid and
* should not be used further.
*
* Note: cairo_path_destroy() should only be called with a
* pointer to a #cairo_path_t returned by a cairo function. Any path
* that is created manually (ie. outside of cairo) should be destroyed
* manually as well.
*
* Since: 1.0
**/
void
cairo_path_destroy (cairo_path_t *path)
{
if (path == NULL || path == &_cairo_path_nil)
return;
free (path->data);
free (path);
}
slim_hidden_def (cairo_path_destroy);
/**
* _cairo_path_create:
* @path: a fixed-point, device-space path to be converted and copied
* @cr: the current graphics context
*
* Creates a user-space #cairo_path_t copy of the given device-space
* @path. The @cr parameter provides the inverse CTM for the
* conversion.
*
* Return value: the new copy of the path. If there is insufficient
* memory a pointer to a special static nil #cairo_path_t will be
* returned instead with status==%CAIRO_STATUS_NO_MEMORY and
* data==%NULL.
**/
cairo_path_t *
_cairo_path_create (cairo_path_fixed_t *path,
cairo_t *cr)
{
return _cairo_path_create_internal (path, cr, FALSE);
}
/**
* _cairo_path_create_flat:
* @path: a fixed-point, device-space path to be flattened, converted and copied
* @cr: the current graphics context
*
* Creates a flattened, user-space #cairo_path_t copy of the given
* device-space @path. The @cr parameter provide the inverse CTM
* for the conversion, as well as the tolerance value to control the
* accuracy of the flattening.
*
* Return value: the flattened copy of the path. If there is insufficient
* memory a pointer to a special static nil #cairo_path_t will be
* returned instead with status==%CAIRO_STATUS_NO_MEMORY and
* data==%NULL.
**/
cairo_path_t *
_cairo_path_create_flat (cairo_path_fixed_t *path,
cairo_t *cr)
{
return _cairo_path_create_internal (path, cr, TRUE);
}
/**
* _cairo_path_append_to_context:
* @path: the path data to be appended
* @cr: a cairo context
*
* Append @path to the current path within @cr.
*
* Return value: %CAIRO_STATUS_INVALID_PATH_DATA if the data in @path
* is invalid, and %CAIRO_STATUS_SUCCESS otherwise.
**/
cairo_status_t
_cairo_path_append_to_context (const cairo_path_t *path,
cairo_t *cr)
{
const cairo_path_data_t *p, *end;
end = &path->data[path->num_data];
for (p = &path->data[0]; p < end; p += p->header.length) {
switch (p->header.type) {
case CAIRO_PATH_MOVE_TO:
if (unlikely (p->header.length < 2))
return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
cairo_move_to (cr, p[1].point.x, p[1].point.y);
break;
case CAIRO_PATH_LINE_TO:
if (unlikely (p->header.length < 2))
return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
cairo_line_to (cr, p[1].point.x, p[1].point.y);
break;
case CAIRO_PATH_CURVE_TO:
if (unlikely (p->header.length < 4))
return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
cairo_curve_to (cr,
p[1].point.x, p[1].point.y,
p[2].point.x, p[2].point.y,
p[3].point.x, p[3].point.y);
break;
case CAIRO_PATH_CLOSE_PATH:
if (unlikely (p->header.length < 1))
return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
cairo_close_path (cr);
break;
default:
return _cairo_error (CAIRO_STATUS_INVALID_PATH_DATA);
}
if (unlikely (cr->status))
return cr->status;
}
return CAIRO_STATUS_SUCCESS;
}