1 //========================================================================
2 // Gamma correction test program
3 // Copyright (c) Camilla Berglund <elmindreda@elmindreda.org>
4 //
5 // This software is provided 'as-is', without any express or implied
6 // warranty. In no event will the authors be held liable for any damages
7 // arising from the use of this software.
8 //
9 // Permission is granted to anyone to use this software for any purpose,
10 // including commercial applications, and to alter it and redistribute it
11 // freely, subject to the following restrictions:
12 //
13 // 1. The origin of this software must not be misrepresented; you must not
14 // claim that you wrote the original software. If you use this software
15 // in a product, an acknowledgment in the product documentation would
16 // be appreciated but is not required.
17 //
18 // 2. Altered source versions must be plainly marked as such, and must not
19 // be misrepresented as being the original software.
20 //
21 // 3. This notice may not be removed or altered from any source
22 // distribution.
23 //
24 //========================================================================
25 //
26 // This program is used to test the gamma correction functionality for
27 // both fullscreen and windowed mode windows
28 //
29 //========================================================================
30
31 #include <GLFW/glfw3.h>
32
33 #include <stdio.h>
34 #include <stdlib.h>
35
36 #include "getopt.h"
37
38 #define STEP_SIZE 0.1f
39
40 static GLfloat gamma_value = 1.0f;
41
usage(void)42 static void usage(void)
43 {
44 printf("Usage: gamma [-h] [-f]\n");
45 }
46
set_gamma(GLFWwindow * window,float value)47 static void set_gamma(GLFWwindow* window, float value)
48 {
49 GLFWmonitor* monitor = glfwGetWindowMonitor(window);
50 if (!monitor)
51 monitor = glfwGetPrimaryMonitor();
52
53 gamma_value = value;
54 printf("Gamma: %f\n", gamma_value);
55 glfwSetGamma(monitor, gamma_value);
56 }
57
error_callback(int error,const char * description)58 static void error_callback(int error, const char* description)
59 {
60 fprintf(stderr, "Error: %s\n", description);
61 }
62
key_callback(GLFWwindow * window,int key,int scancode,int action,int mods)63 static void key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
64 {
65 if (action != GLFW_PRESS)
66 return;
67
68 switch (key)
69 {
70 case GLFW_KEY_ESCAPE:
71 {
72 glfwSetWindowShouldClose(window, GL_TRUE);
73 break;
74 }
75
76 case GLFW_KEY_KP_ADD:
77 case GLFW_KEY_Q:
78 {
79 set_gamma(window, gamma_value + STEP_SIZE);
80 break;
81 }
82
83 case GLFW_KEY_KP_SUBTRACT:
84 case GLFW_KEY_W:
85 {
86 if (gamma_value - STEP_SIZE > 0.f)
87 set_gamma(window, gamma_value - STEP_SIZE);
88
89 break;
90 }
91 }
92 }
93
framebuffer_size_callback(GLFWwindow * window,int width,int height)94 static void framebuffer_size_callback(GLFWwindow* window, int width, int height)
95 {
96 glViewport(0, 0, width, height);
97 }
98
main(int argc,char ** argv)99 int main(int argc, char** argv)
100 {
101 int width, height, ch;
102 GLFWmonitor* monitor = NULL;
103 GLFWwindow* window;
104
105 glfwSetErrorCallback(error_callback);
106
107 if (!glfwInit())
108 exit(EXIT_FAILURE);
109
110 while ((ch = getopt(argc, argv, "fh")) != -1)
111 {
112 switch (ch)
113 {
114 case 'h':
115 usage();
116 exit(EXIT_SUCCESS);
117
118 case 'f':
119 monitor = glfwGetPrimaryMonitor();
120 break;
121
122 default:
123 usage();
124 exit(EXIT_FAILURE);
125 }
126 }
127
128 if (monitor)
129 {
130 const GLFWvidmode* mode = glfwGetVideoMode(monitor);
131 width = mode->width;
132 height = mode->height;
133 }
134 else
135 {
136 width = 200;
137 height = 200;
138 }
139
140 window = glfwCreateWindow(width, height, "Gamma Test", monitor, NULL);
141 if (!window)
142 {
143 glfwTerminate();
144 exit(EXIT_FAILURE);
145 }
146
147 set_gamma(window, 1.f);
148
149 glfwMakeContextCurrent(window);
150 glfwSwapInterval(1);
151
152 glfwSetKeyCallback(window, key_callback);
153 glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
154
155 glMatrixMode(GL_PROJECTION);
156 glOrtho(-1.f, 1.f, -1.f, 1.f, -1.f, 1.f);
157 glMatrixMode(GL_MODELVIEW);
158
159 glClearColor(0.5f, 0.5f, 0.5f, 0);
160
161 while (!glfwWindowShouldClose(window))
162 {
163 glClear(GL_COLOR_BUFFER_BIT);
164
165 glColor3f(0.8f, 0.2f, 0.4f);
166 glRectf(-0.5f, -0.5f, 0.5f, 0.5f);
167
168 glfwSwapBuffers(window);
169 glfwWaitEvents();
170 }
171
172 glfwTerminate();
173 exit(EXIT_SUCCESS);
174 }
175
176