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
|
/*************************************************************************
* Copyright (C) 2009-2010 Tavian Barnes <tavianator@gmail.com> *
* *
* This file is part of The Dimension Library. *
* *
* The Dimension Library is free software; you can redistribute it and/ *
* or modify it under the terms of the GNU Lesser General Public License *
* as published by the Free Software Foundation; either version 3 of the *
* License, or (at your option) any later version. *
* *
* The Dimension Library is distributed in the hope that it will be *
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty *
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *
* Lesser General Public License for more details. *
* *
* You should have received a copy of the GNU Lesser General Public *
* License along with this program. If not, see *
* <http://www.gnu.org/licenses/>. *
*************************************************************************/
#include "dimension.h"
#include <GL/gl.h>
#include <stdlib.h>
#include <stdint.h>
/* GL optimizer callback */
static void dmnsn_gl_optimizer_fn(dmnsn_canvas *canvas,
dmnsn_canvas_optimizer optimizer,
size_t x, size_t y);
/* Optimize canvas for GL drawing */
int
dmnsn_gl_optimize_canvas(dmnsn_canvas *canvas)
{
/* Check if we've already optimized this canvas */
DMNSN_ARRAY_FOREACH (dmnsn_canvas_optimizer *, i, canvas->optimizers) {
if (i->optimizer_fn == &dmnsn_gl_optimizer_fn) {
return 0;
}
}
dmnsn_canvas_optimizer optimizer;
optimizer.optimizer_fn = &dmnsn_gl_optimizer_fn;
optimizer.free_fn = &dmnsn_free;
/* Allocate a buffer to hold RGB values */
optimizer.ptr = dmnsn_malloc(4*canvas->x*canvas->y*sizeof(GLushort));
/* Set a new optimizer */
dmnsn_optimize_canvas(canvas, optimizer);
return 0;
}
/* Write canvas to GL framebuffer. Returns 0 on success, nonzero on failure */
int
dmnsn_gl_write_canvas(const dmnsn_canvas *canvas)
{
GLushort *pixels; /* Array of 16-bit ints in RGBA order */
GLushort *pixel;
dmnsn_sRGB sRGB;
dmnsn_color color;
size_t width = canvas->x;
size_t height = canvas->y;
/* Check if we can optimize this */
DMNSN_ARRAY_FOREACH (dmnsn_canvas_optimizer *, i, canvas->optimizers) {
if (i->optimizer_fn == &dmnsn_gl_optimizer_fn) {
glDrawPixels(width, height, GL_RGBA, GL_UNSIGNED_SHORT, i->ptr);
return glGetError() == GL_NO_ERROR ? 0 : 1;
}
}
/* We couldn't, so transform the canvas to RGB now */
pixels = dmnsn_malloc(4*width*height*sizeof(GLushort));
for (size_t y = 0; y < height; ++y) {
for (size_t x = 0; x < width; ++x) {
pixel = pixels + 4*(y*width + x);
color = dmnsn_get_pixel(canvas, x, y);
sRGB = dmnsn_sRGB_from_color(color);
/* Saturate R, G, and B to [0, UINT16_MAX] */
if (sRGB.R <= 0.0) {
pixel[0] = 0;
} else if (sRGB.R >= 1.0) {
pixel[0] = UINT16_MAX;
} else {
pixel[0] = sRGB.R*UINT16_MAX;
}
if (sRGB.G <= 0.0) {
pixel[1] = 0;
} else if (sRGB.G >= 1.0) {
pixel[1] = UINT16_MAX;
} else {
pixel[1] = sRGB.G*UINT16_MAX;
}
if (sRGB.B <= 0.0) {
pixel[2] = 0;
} else if (sRGB.B >= 1.0) {
pixel[2] = UINT16_MAX;
} else {
pixel[2] = sRGB.B*UINT16_MAX;
}
/* color.filter + color.trans is in [0.0, 1.0] by definition */
pixel[3] = (color.filter + color.trans)*UINT16_MAX;
}
}
glDrawPixels(width, height, GL_RGBA, GL_UNSIGNED_SHORT, pixels);
dmnsn_free(pixels);
return glGetError() == GL_NO_ERROR ? 0 : 1;
}
/* Read a canvas from a GL framebuffer. Returns NULL on failure. */
dmnsn_canvas *
dmnsn_gl_read_canvas(size_t x0, size_t y0,
size_t width, size_t height)
{
dmnsn_canvas *canvas;
GLushort *pixels; /* Array of 16-bit ints in RGBA order */
GLushort *pixel;
dmnsn_sRGB sRGB;
dmnsn_color color;
canvas = dmnsn_new_canvas(width, height);
pixels = dmnsn_malloc(4*width*height*sizeof(GLushort));
glReadPixels(x0, y0, width, height, GL_RGBA, GL_UNSIGNED_SHORT, pixels);
if (glGetError() != GL_NO_ERROR) {
dmnsn_free(pixels);
dmnsn_delete_canvas(canvas);
return NULL;
}
for (size_t y = 0; y < height; ++y) {
for (size_t x = 0; x < width; ++x) {
pixel = pixels + 4*(y*width + x);
sRGB.R = ((double)pixel[0])/UINT16_MAX;
sRGB.G = ((double)pixel[1])/UINT16_MAX;
sRGB.B = ((double)pixel[2])/UINT16_MAX;
color = dmnsn_color_from_sRGB(sRGB);
color.filter = ((double)pixel[3])/UINT16_MAX;
dmnsn_set_pixel(canvas, x, y, color);
}
}
dmnsn_free(pixels);
return canvas;
}
/* GL optimizer callback */
static void
dmnsn_gl_optimizer_fn(dmnsn_canvas *canvas, dmnsn_canvas_optimizer optimizer,
size_t x, size_t y)
{
dmnsn_color color;
dmnsn_sRGB sRGB;
GLushort *pixel = (GLushort *)optimizer.ptr + 4*(y*canvas->x + x);
color = dmnsn_get_pixel(canvas, x, y);
sRGB = dmnsn_sRGB_from_color(color);
/* Saturate R, G, and B to [0, UINT16_MAX] */
if (sRGB.R <= 0.0) {
pixel[0] = 0;
} else if (sRGB.R >= 1.0) {
pixel[0] = UINT16_MAX;
} else {
pixel[0] = sRGB.R*UINT16_MAX;
}
if (sRGB.G <= 0.0) {
pixel[1] = 0;
} else if (sRGB.G >= 1.0) {
pixel[1] = UINT16_MAX;
} else {
pixel[1] = sRGB.G*UINT16_MAX;
}
if (sRGB.B <= 0.0) {
pixel[2] = 0;
} else if (sRGB.B >= 1.0) {
pixel[2] = UINT16_MAX;
} else {
pixel[2] = sRGB.B*UINT16_MAX;
}
/* color.filter + color.trans is in [0.0, 1.0] by definition */
pixel[3] = (color.filter + color.trans)*UINT16_MAX;
}
|
