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
|
#include "app.h"
#include "platform.h"
bool
compile_shaders(const char *vert, const char *frag, u32 *handle,
PlatformAPI platform) {
int success = 0;
char memory[MB(1)] = {0}; // Memory for reading shader files
// Initialize shader handles.
u32 vert_handle = glCreateShader(GL_VERTEX_SHADER);
u32 frag_handle = glCreateShader(GL_FRAGMENT_SHADER);
// Vertex shader.
{
platform.read_file(vert, memory);
const char * source = memory;
glShaderSource(vert_handle, 1, &source, NULL);
glCompileShader(vert_handle);
glGetShaderiv(vert_handle, GL_COMPILE_STATUS, &success);
if (!success) {
glDeleteShader(vert_handle);
glDeleteShader(frag_handle);
return false;
}
}
// Fragment shader.
{
platform.read_file(frag, memory);
const char * source = memory;
glShaderSource(frag_handle, 1, &source, NULL);
glCompileShader(frag_handle);
glGetShaderiv(frag_handle, GL_COMPILE_STATUS, &success);
if (!success) {
glDeleteShader(vert_handle);
glDeleteShader(frag_handle);
return false;
}
}
// Program linkage.
*handle = glCreateProgram();
glAttachShader(*handle, vert_handle);
glAttachShader(*handle, frag_handle);
glLinkProgram(*handle);
glGetProgramiv(*handle, GL_LINK_STATUS, &success);
if(!success) {
glDeleteProgram(*handle);
glDeleteShader(vert_handle);
glDeleteShader(frag_handle);
return false;
}
glDeleteShader(vert_handle);
glDeleteShader(frag_handle);
return true;
}
static inline bool
app_init(AppState *state, PlatformAPI platform) {
platform.log("INIT");
// Initialize GLFW.
if (!glfwInit()) {
platform.log("ERROR: failed to initialize GLFW");
return false;
}
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
// Initialize window.
GLFWwindow* window = glfwCreateWindow(400, 300, "Hello MIC", NULL, NULL);
if (window == NULL) {
platform.log("ERROR: failed to create GLFW window");
glfwTerminate();
return false;
}
glfwMakeContextCurrent(window);
// Initialize GLEW.
if(glewInit() != GLEW_OK) {
platform.log("ERROR: glew initialization");
glfwTerminate();
return false;
}
// Initialize viewport.
glViewport(0, 0, 400, 300);
// Initialize vertex data.
state->vertices[0] = -0.5f;
state->vertices[1] = -0.5f;
state->vertices[2] = 0.0f;
state->vertices[3] = 0.5f;
state->vertices[4] = -0.5f;
state->vertices[5] = 0.0f;
state->vertices[6] = 0.0f;
state->vertices[7] = 0.5f;
state->vertices[8] = 0.0f;
// Initialize Vertex Buffer Object (VBO) and Vertex Array Object (VAO).
u32 VBO;
glGenBuffers(1, &VBO);
u32 VAO;
glGenVertexArrays(1, &VAO);
// Bind the VAO before any other binding.
glBindVertexArray(VAO);
// Send vertex data to VBO.
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(state->vertices), state->vertices,
GL_STATIC_DRAW);
// Set vertex attribute pointers.
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), 0);
// Compile shader program.
const char *vert = "shaders/triangle.vert";
const char *frag = "shaders/triangle.frag";
if (!compile_shaders(vert, frag, &state->shader_program, platform)) {
platform.log("WARNING: failed to compile shader program");
}
// Initialize application state.
state->window = window;
state->VBO = VBO;
state->VAO = VAO;
return true;
}
static inline void
app_destroy(AppState *state, PlatformAPI platform) {
(void)state; // Unused parameter.
platform.log("DESTROY");
}
static inline void
app_reload(AppState *state, PlatformAPI platform) {
platform.log("RELOAD");
const char *vert = "shaders/triangle.vert";
const char *frag = "shaders/triangle.frag";
if (!compile_shaders(vert, frag, &state->shader_program, platform)) {
platform.log("WARNING: failed to compile shader program");
}
}
static inline void
app_unload(AppState *state, PlatformAPI platform) {
(void)state; // Unused parameter.
platform.log("UNLOAD");
}
static inline bool
app_step(AppState *state, PlatformAPI platform) {
(void)platform; // Unused parameter
glClearColor(0.8f, 0.0f, 0.4f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
glUseProgram(state->shader_program);
glBindVertexArray(state->VAO);
glDrawArrays(GL_TRIANGLES, 0, 3);
glfwSwapBuffers(state->window);
glfwPollEvents();
return true;
}
const AppAPI APP_API = {
.init = app_init,
.destroy = app_destroy,
.reload = app_reload,
.step = app_step,
.unload = app_unload,
};
|
