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
|
// Copyright (c) 2011 The Native Client Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "examples/tumbler/shader_util.h"
#include <stdlib.h>
#include <stdio.h>
namespace shader_util {
GLuint CreateShaderOfType(GLenum type, const char *shader_src) {
GLuint shader;
GLint compiled;
// Create the shader object
shader = glCreateShader(type);
if (shader == 0)
return 0;
// Load and compile the shader source
glShaderSource(shader, 1, &shader_src, NULL);
glCompileShader(shader);
// Check the compile status
glGetShaderiv(shader, GL_COMPILE_STATUS, &compiled);
if (compiled == 0) {
GLint info_len = 0;
glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &info_len);
if (info_len > 1) {
char* info_log = reinterpret_cast<char*>(malloc(sizeof(char) * info_len));
glGetShaderInfoLog(shader, info_len, NULL, info_log);
// TODO(dspringer): We could really use a logging API.
printf("Error compiling shader:\n%s\n", info_log);
free(info_log);
}
glDeleteShader(shader);
return 0;
}
return shader;
}
GLuint CreateProgramFromVertexAndFragmentShaders(
const char *vertex_shader_src, const char *fragment_shader_src) {
GLuint vertex_shader;
GLuint fragment_shader;
GLuint program_object;
GLint linked;
// Load the vertex/fragment shaders
vertex_shader = CreateShaderOfType(GL_VERTEX_SHADER, vertex_shader_src);
if (vertex_shader == 0)
return 0;
fragment_shader = CreateShaderOfType(GL_FRAGMENT_SHADER, fragment_shader_src);
if (fragment_shader == 0) {
glDeleteShader(vertex_shader);
return 0;
}
// Create the program object and attach the shaders.
program_object = glCreateProgram();
if (program_object == 0)
return 0;
glAttachShader(program_object, vertex_shader);
glAttachShader(program_object, fragment_shader);
// Link the program
glLinkProgram(program_object);
// Check the link status
glGetProgramiv(program_object, GL_LINK_STATUS, &linked);
if (linked == 0) {
GLint info_len = 0;
glGetProgramiv(program_object, GL_INFO_LOG_LENGTH, &info_len);
if (info_len > 1) {
char* info_log = reinterpret_cast<char*>(malloc(info_len));
glGetProgramInfoLog(program_object, info_len, NULL, info_log);
// TODO(dspringer): We could really use a logging API.
printf("Error linking program:\n%s\n", info_log);
free(info_log);
}
glDeleteProgram(program_object);
return 0;
}
// Delete these here because they are attached to the program object.
glDeleteShader(vertex_shader);
glDeleteShader(fragment_shader);
return program_object;
}
} // namespace shader_util
|
