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
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
/*
* Copyright © 2000 SuSE, Inc.
* Copyright © 2007 Red Hat, Inc.
* Copyright © 2000 Keith Packard, member of The XFree86 Project, Inc.
* 2005 Lars Knoll & Zack Rusin, Trolltech
*
* 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 Keith Packard not be used in
* advertising or publicity pertaining to distribution of the software without
* specific, written prior permission. Keith Packard makes no
* representations about the suitability of this software for any purpose. It
* is provided "as is" without express or implied warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS 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
#include <stdlib.h>
#include <math.h>
#include "pixman-private.h"
static force_inline double
coordinates_to_parameter (double x, double y, double angle)
{
double t;
t = atan2 (y, x) + angle;
while (t < 0)
t += 2 * M_PI;
while (t >= 2 * M_PI)
t -= 2 * M_PI;
return 1 - t * (1 / (2 * M_PI)); /* Scale t to [0, 1] and
* make rotation CCW
*/
}
static uint32_t *
conical_get_scanline (pixman_iter_t *iter,
const uint32_t *mask,
int Bpp,
pixman_gradient_walker_write_t write_pixel)
{
pixman_image_t *image = iter->image;
int x = iter->x;
int y = iter->y;
int width = iter->width;
uint32_t *buffer = iter->buffer;
gradient_t *gradient = (gradient_t *)image;
conical_gradient_t *conical = (conical_gradient_t *)image;
uint32_t *end = buffer + width * (Bpp / 4);
pixman_gradient_walker_t walker;
pixman_bool_t affine = TRUE;
double cx = 1.;
double cy = 0.;
double cz = 0.;
double rx = x + 0.5;
double ry = y + 0.5;
double rz = 1.;
_pixman_gradient_walker_init (&walker, gradient, image->common.repeat);
if (image->common.transform)
{
pixman_vector_t v;
/* reference point is the center of the pixel */
v.vector[0] = pixman_int_to_fixed (x) + pixman_fixed_1 / 2;
v.vector[1] = pixman_int_to_fixed (y) + pixman_fixed_1 / 2;
v.vector[2] = pixman_fixed_1;
if (!pixman_transform_point_3d (image->common.transform, &v))
return iter->buffer;
cx = image->common.transform->matrix[0][0] / 65536.;
cy = image->common.transform->matrix[1][0] / 65536.;
cz = image->common.transform->matrix[2][0] / 65536.;
rx = v.vector[0] / 65536.;
ry = v.vector[1] / 65536.;
rz = v.vector[2] / 65536.;
affine =
image->common.transform->matrix[2][0] == 0 &&
v.vector[2] == pixman_fixed_1;
}
if (affine)
{
rx -= conical->center.x / 65536.;
ry -= conical->center.y / 65536.;
while (buffer < end)
{
if (!mask || *mask++)
{
double t = coordinates_to_parameter (rx, ry, conical->angle);
write_pixel (&walker,
(pixman_fixed_48_16_t)pixman_double_to_fixed (t),
buffer);
}
buffer += (Bpp / 4);
rx += cx;
ry += cy;
}
}
else
{
while (buffer < end)
{
double x, y;
if (!mask || *mask++)
{
double t;
if (rz != 0)
{
x = rx / rz;
y = ry / rz;
}
else
{
x = y = 0.;
}
x -= conical->center.x / 65536.;
y -= conical->center.y / 65536.;
t = coordinates_to_parameter (x, y, conical->angle);
write_pixel (&walker,
(pixman_fixed_48_16_t)pixman_double_to_fixed (t),
buffer);
}
buffer += (Bpp / 4);
rx += cx;
ry += cy;
rz += cz;
}
}
iter->y++;
return iter->buffer;
}
static uint32_t *
conical_get_scanline_narrow (pixman_iter_t *iter, const uint32_t *mask)
{
return conical_get_scanline (iter, mask, 4,
_pixman_gradient_walker_write_narrow);
}
static uint32_t *
conical_get_scanline_wide (pixman_iter_t *iter, const uint32_t *mask)
{
return conical_get_scanline (iter, NULL, 16,
_pixman_gradient_walker_write_wide);
}
void
_pixman_conical_gradient_iter_init (pixman_image_t *image, pixman_iter_t *iter)
{
if (iter->iter_flags & ITER_NARROW)
iter->get_scanline = conical_get_scanline_narrow;
else
iter->get_scanline = conical_get_scanline_wide;
}
PIXMAN_EXPORT pixman_image_t *
pixman_image_create_conical_gradient (const pixman_point_fixed_t * center,
pixman_fixed_t angle,
const pixman_gradient_stop_t *stops,
int n_stops)
{
pixman_image_t *image = _pixman_image_allocate ();
conical_gradient_t *conical;
if (!image)
return NULL;
conical = &image->conical;
if (!_pixman_init_gradient (&conical->common, stops, n_stops))
{
free (image);
return NULL;
}
angle = MOD (angle, pixman_int_to_fixed (360));
image->type = CONICAL;
conical->center = *center;
conical->angle = (pixman_fixed_to_double (angle) / 180.0) * M_PI;
return image;
}
|
