1 //========================================================================
2 // Gamma correction test program
3 // Copyright (c) Camilla Löwy <elmindreda@glfw.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 full screen and windowed mode windows
28 //
29 //========================================================================
30 
31 #include <glad/gl.h>
32 #include <GLFW/glfw3.h>
33 
34 #define NK_IMPLEMENTATION
35 #define NK_INCLUDE_FIXED_TYPES
36 #define NK_INCLUDE_FONT_BAKING
37 #define NK_INCLUDE_DEFAULT_FONT
38 #define NK_INCLUDE_DEFAULT_ALLOCATOR
39 #define NK_INCLUDE_VERTEX_BUFFER_OUTPUT
40 #define NK_INCLUDE_STANDARD_VARARGS
41 #define NK_BUTTON_TRIGGER_ON_RELEASE
42 #include <nuklear.h>
43 
44 #define NK_GLFW_GL2_IMPLEMENTATION
45 #include <nuklear_glfw_gl2.h>
46 
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 
error_callback(int error,const char * description)51 static void error_callback(int error, const char* description)
52 {
53     fprintf(stderr, "Error: %s\n", description);
54 }
55 
key_callback(GLFWwindow * window,int key,int scancode,int action,int mods)56 static void key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
57 {
58     if (action == GLFW_PRESS && key == GLFW_KEY_ESCAPE)
59         glfwSetWindowShouldClose(window, GLFW_TRUE);
60 }
61 
chart_ramp_array(struct nk_context * nk,struct nk_color color,int count,unsigned short int * values)62 static void chart_ramp_array(struct nk_context* nk,
63                              struct nk_color color,
64                              int count, unsigned short int* values)
65 {
66     if (nk_chart_begin_colored(nk, NK_CHART_LINES,
67                                color, nk_rgb(255, 255, 255),
68                                count, 0, 65535))
69     {
70         int i;
71         for (i = 0;  i < count;  i++)
72         {
73             char buffer[1024];
74             if (nk_chart_push(nk, values[i]))
75             {
76                 snprintf(buffer, sizeof(buffer), "#%u: %u (%0.5f) ",
77                          i, values[i], values[i] / 65535.f);
78                 nk_tooltip(nk, buffer);
79             }
80         }
81 
82         nk_chart_end(nk);
83     }
84 }
85 
main(int argc,char ** argv)86 int main(int argc, char** argv)
87 {
88     GLFWmonitor* monitor = NULL;
89     GLFWwindow* window;
90     GLFWgammaramp orig_ramp;
91     struct nk_context* nk;
92     struct nk_font_atlas* atlas;
93     float gamma_value = 1.f;
94 
95     glfwSetErrorCallback(error_callback);
96 
97     if (!glfwInit())
98         exit(EXIT_FAILURE);
99 
100     monitor = glfwGetPrimaryMonitor();
101 
102     glfwWindowHint(GLFW_SCALE_TO_MONITOR, GLFW_TRUE);
103 
104     window = glfwCreateWindow(800, 400, "Gamma Test", NULL, NULL);
105     if (!window)
106     {
107         glfwTerminate();
108         exit(EXIT_FAILURE);
109     }
110 
111     {
112         const GLFWgammaramp* ramp = glfwGetGammaRamp(monitor);
113         const size_t array_size = ramp->size * sizeof(short);
114         orig_ramp.size = ramp->size;
115         orig_ramp.red = malloc(array_size);
116         orig_ramp.green = malloc(array_size);
117         orig_ramp.blue = malloc(array_size);
118         memcpy(orig_ramp.red, ramp->red, array_size);
119         memcpy(orig_ramp.green, ramp->green, array_size);
120         memcpy(orig_ramp.blue, ramp->blue, array_size);
121     }
122 
123     glfwMakeContextCurrent(window);
124     gladLoadGL(glfwGetProcAddress);
125     glfwSwapInterval(1);
126 
127     nk = nk_glfw3_init(window, NK_GLFW3_INSTALL_CALLBACKS);
128     nk_glfw3_font_stash_begin(&atlas);
129     nk_glfw3_font_stash_end();
130 
131     glfwSetKeyCallback(window, key_callback);
132 
133     while (!glfwWindowShouldClose(window))
134     {
135         int width, height;
136         struct nk_rect area;
137 
138         glfwGetWindowSize(window, &width, &height);
139         area = nk_rect(0.f, 0.f, (float) width, (float) height);
140         nk_window_set_bounds(nk, "", area);
141 
142         glClear(GL_COLOR_BUFFER_BIT);
143         nk_glfw3_new_frame();
144         if (nk_begin(nk, "", area, 0))
145         {
146             const GLFWgammaramp* ramp;
147 
148             nk_layout_row_dynamic(nk, 30, 3);
149             if (nk_slider_float(nk, 0.1f, &gamma_value, 5.f, 0.1f))
150                 glfwSetGamma(monitor, gamma_value);
151             nk_labelf(nk, NK_TEXT_LEFT, "%0.1f", gamma_value);
152             if (nk_button_label(nk, "Revert"))
153                 glfwSetGammaRamp(monitor, &orig_ramp);
154 
155             ramp = glfwGetGammaRamp(monitor);
156 
157             nk_layout_row_dynamic(nk, height - 60.f, 3);
158             chart_ramp_array(nk, nk_rgb(255, 0, 0), ramp->size, ramp->red);
159             chart_ramp_array(nk, nk_rgb(0, 255, 0), ramp->size, ramp->green);
160             chart_ramp_array(nk, nk_rgb(0, 0, 255), ramp->size, ramp->blue);
161         }
162 
163         nk_end(nk);
164         nk_glfw3_render(NK_ANTI_ALIASING_ON);
165 
166         glfwSwapBuffers(window);
167         glfwWaitEventsTimeout(1.0);
168     }
169 
170     free(orig_ramp.red);
171     free(orig_ramp.green);
172     free(orig_ramp.blue);
173 
174     nk_glfw3_shutdown();
175     glfwTerminate();
176     exit(EXIT_SUCCESS);
177 }
178 
179