1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
|
/*
* Copyright © 2016 Red Hat, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software
* and its documentation for any purpose is hereby granted without
* fee, provided that the above copyright notice appear in all copies
* and that both that copyright notice and this permission notice
* appear in supporting documentation, and that the name of Red Hat
* not be used in advertising or publicity pertaining to distribution
* of the software without specific, written prior permission. Red
* Hat makes no representations about the suitability of this software
* for any purpose. It is provided "as is" without express or implied
* warranty.
*
* THE AUTHORS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
* NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
* OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
* NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifndef BEZIER_H
#define BEZIER_H
#include <stdlib.h>
#include <stdbool.h>
struct bezier_control_point {
double x, y;
};
extern const struct bezier_control_point bezier_defaults[4];
/**
* Given four control points in the range [(0.0/0.0), (1.0/1.0)]
* construct a Bézier curve.
*
* ^
*1.0 | c2 ______ c3
* | _/
* | /
* |c1 /
* | /
* | /
* |/_________________>
* c0 1.0
*
* This function requires that c[i].x <= c[i+1].x
*
* The curve is mapped into a canvas size [0, bezier_sz)². For each x
* coordiante in [0, bezier_sz), the matching y coordinate is thus
* bezier[x].
*
* In other words, if you have a range [0,2048) input possible values,
* the output is a list of 2048 points in a [0, 2048) range.
*
* @return true on success, false otherwise
*/
bool
cubic_bezier(const struct bezier_control_point controls[4],
int *bezier,
size_t bezier_sz);
#endif
|
