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
221
222
223
224
225
226
227
228
229
230
|
#include <epoxy/gl.h>
#include <math.h>
#include <string>
#include <vector>
#include "resource_pool.h"
#include "widgets.h"
#include "util.h"
#define HSV_WHEEL_SIZE 128
using namespace std;
namespace movit {
GLuint hsv_wheel_texnum = 0;
GLuint textured_program_num = 0, colored_program_num = 0, hsv_vao = 0;
ResourcePool resource_pool;
void draw_black_point(float x, float y, float point_size)
{
glUseProgram(colored_program_num);
check_error();
float vertices[] = { x, y };
float colors[] = { 0.0f, 0.0f, 0.0f };
glPointSize(point_size);
check_error();
GLuint position_vbo = fill_vertex_attribute(colored_program_num, "position", 2, GL_FLOAT, sizeof(vertices), vertices);
GLuint color_vbo = fill_vertex_attribute(colored_program_num, "color", 3, GL_FLOAT, sizeof(colors), colors);
check_error();
glDrawArrays(GL_POINTS, 0, 1);
check_error();
cleanup_vertex_attribute(colored_program_num, "position", position_vbo);
cleanup_vertex_attribute(colored_program_num, "color", color_vbo);
}
void draw_hsv_wheel(float y, float rad, float theta, float value)
{
glUseProgram(textured_program_num);
check_error();
glActiveTexture(GL_TEXTURE0);
check_error();
glBindTexture(GL_TEXTURE_2D, hsv_wheel_texnum);
check_error();
glUniform1i(glGetUniformLocation(textured_program_num, "tex"), 0); // Bind the 2D sampler.
check_error();
glEnable(GL_BLEND);
check_error();
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
check_error();
GLuint vao;
glGenVertexArrays(1, &vao);
check_error();
glBindVertexArray(vao);
check_error();
// wheel
float wheel_vertices[] = {
0.0f, y,
0.0f, y + 0.2f,
0.2f * 9.0f / 16.0f, y,
0.2f * 9.0f / 16.0f, y + 0.2f,
};
float wheel_texcoords[] = {
0.0f, 1.0f,
0.0f, 0.0f,
1.0f, 1.0f,
1.0f, 0.0f,
};
GLuint position_vbo = fill_vertex_attribute(textured_program_num, "position", 2, GL_FLOAT, sizeof(wheel_vertices), wheel_vertices);
GLuint texcoord_vbo = fill_vertex_attribute(textured_program_num, "texcoord", 2, GL_FLOAT, sizeof(wheel_texcoords), wheel_texcoords);
check_error();
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
check_error();
cleanup_vertex_attribute(textured_program_num, "position", position_vbo);
cleanup_vertex_attribute(textured_program_num, "texcoord", texcoord_vbo);
// wheel selector
draw_black_point(
(0.1f + rad * cos(theta) * 0.1f) * 9.0f / 16.0f,
y + 0.1f - rad * sin(theta) * 0.1f,
5.0f);
// value slider
glUseProgram(colored_program_num);
float value_vertices[] = {
0.22f * 9.0f / 16.0f, y,
0.22f * 9.0f / 16.0f, y + 0.2f,
0.24f * 9.0f / 16.0f, y,
0.24f * 9.0f / 16.0f, y + 0.2f,
};
float value_colors[] = {
0.0f, 0.0f, 0.0f,
1.0f, 1.0f, 1.0f,
0.0f, 0.0f, 0.0f,
1.0f, 1.0f, 1.0f,
};
position_vbo = fill_vertex_attribute(colored_program_num, "position", 2, GL_FLOAT, sizeof(value_vertices), value_vertices);
GLuint color_vbo = fill_vertex_attribute(colored_program_num, "color", 3, GL_FLOAT, sizeof(value_colors), value_colors);
check_error();
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
check_error();
cleanup_vertex_attribute(colored_program_num, "position", position_vbo);
cleanup_vertex_attribute(colored_program_num, "color", color_vbo);
// value selector
draw_black_point(0.23f * 9.0f / 16.0f, y + value * 0.2f, 5.0f);
glDeleteVertexArrays(1, &vao);
check_error();
glUseProgram(0);
check_error();
}
void draw_saturation_bar(float y, float saturation)
{
GLuint vao;
glGenVertexArrays(1, &vao);
check_error();
glBindVertexArray(vao);
check_error();
// value slider
glUseProgram(colored_program_num);
float value_vertices[] = {
0.0f * 9.0f / 16.0f, y + 0.02f,
0.2f * 9.0f / 16.0f, y + 0.02f,
0.0f * 9.0f / 16.0f, y,
0.2f * 9.0f / 16.0f, y,
};
float value_colors[] = {
0.0f, 0.0f, 0.0f,
1.0f, 1.0f, 1.0f,
0.0f, 0.0f, 0.0f,
1.0f, 1.0f, 1.0f,
};
GLuint position_vbo = fill_vertex_attribute(colored_program_num, "position", 2, GL_FLOAT, sizeof(value_vertices), value_vertices);
GLuint color_vbo = fill_vertex_attribute(colored_program_num, "color", 3, GL_FLOAT, sizeof(value_colors), value_colors);
check_error();
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
check_error();
cleanup_vertex_attribute(colored_program_num, "position", position_vbo);
cleanup_vertex_attribute(colored_program_num, "color", color_vbo);
// value selector
draw_black_point(0.2f * saturation * 9.0f / 16.0f, y + 0.01f, 5.0f);
glDeleteVertexArrays(1, &vao);
check_error();
glUseProgram(0);
check_error();
}
void make_hsv_wheel_texture()
{
glGenTextures(1, &hsv_wheel_texnum);
static unsigned char hsv_pix[HSV_WHEEL_SIZE * HSV_WHEEL_SIZE * 4];
for (int y = 0; y < HSV_WHEEL_SIZE; ++y) {
for (int x = 0; x < HSV_WHEEL_SIZE; ++x) {
float yf = 2.0f * y / (float)(HSV_WHEEL_SIZE) - 1.0f;
float xf = 2.0f * x / (float)(HSV_WHEEL_SIZE) - 1.0f;
float rad = hypot(xf, yf);
float theta = atan2(yf, xf);
float r, g, b;
hsv2rgb(theta, rad, 1.0f, &r, &g, &b);
hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 0] = lrintf(r * 255.0f);
hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 1] = lrintf(g * 255.0f);
hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 2] = lrintf(b * 255.0f);
if (rad > 1.0f) {
hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 3] = 0;
} else {
hsv_pix[(y * HSV_WHEEL_SIZE + x) * 4 + 3] = 255;
}
}
}
glBindTexture(GL_TEXTURE_2D, hsv_wheel_texnum);
check_error();
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
check_error();
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, HSV_WHEEL_SIZE, HSV_WHEEL_SIZE, 0, GL_RGBA, GL_UNSIGNED_BYTE, hsv_pix);
check_error();
}
void init_hsv_resources()
{
vector<string> frag_shader_outputs;
textured_program_num = resource_pool.compile_glsl_program(
read_version_dependent_file("vs", "vert"),
read_version_dependent_file("texture1d", "frag"),
frag_shader_outputs);
colored_program_num = resource_pool.compile_glsl_program(
read_version_dependent_file("vs-color", "vert"),
read_version_dependent_file("color", "frag"),
frag_shader_outputs);
make_hsv_wheel_texture();
}
void cleanup_hsv_resources()
{
resource_pool.release_glsl_program(textured_program_num);
resource_pool.release_glsl_program(colored_program_num);
}
void read_colorwheel(float xf, float yf, float *rad, float *theta, float *value)
{
if (xf < 0.2f && yf < 0.2f) {
float xp = 2.0f * xf / 0.2f - 1.0f;
float yp = -(2.0f * yf / 0.2f - 1.0f);
*rad = hypot(xp, yp);
*theta = atan2(yp, xp);
if (*rad > 1.0) {
*rad = 1.0;
}
} else if (xf >= 0.22f && xf <= 0.24f) {
*value = yf / 0.2f;
}
}
} // namespace movit
|
