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
|
#ifndef LLMR_GEOMETRY_VAO
#define LLMR_GEOMETRY_VAO
#include <llmr/platform/gl.hpp>
#include <stdexcept>
namespace llmr {
class VertexArrayObject {
public:
template <typename Shader, typename VertexBuffer>
void bind(Shader& shader, VertexBuffer& vertex_buffer, char *offset) {
#ifdef GL_ARB_vertex_array_object
if (!vao) {
glGenVertexArrays(1, &vao);
glBindVertexArray(vao);
} else {
// We have been given the correct information.
glBindVertexArray(vao);
}
if (shader_ptr != &shader) {
if (shader_ptr != nullptr) {
fprintf(stderr, "shader rebind!");
}
#endif
vertex_buffer.bind();
shader.bind(offset);
#ifdef GL_ARB_vertex_array_object
shader_ptr = &shader;
vertex_buffer_ptr = &vertex_buffer;
elements_buffer_ptr = nullptr;
offset_ptr = offset;
} else if (vertex_buffer_ptr != &vertex_buffer) {
throw std::runtime_error("trying to bind VAO to another vertex buffer");
} else if (elements_buffer_ptr != nullptr) {
throw std::runtime_error("trying to bind VAO to another elements buffer");
} else if (offset_ptr != offset) {
throw std::runtime_error("trying to bind VAO to another offset");
}
#endif
}
template <typename Shader, typename VertexBuffer, typename ElementsBuffer>
void bind(Shader& shader, VertexBuffer& vertex_buffer, ElementsBuffer& elements_buffer, char *offset) {
#ifdef GL_ARB_vertex_array_object
if (!vao) {
glGenVertexArrays(1, &vao);
glBindVertexArray(vao);
} else {
// We have been given the correct information.
glBindVertexArray(vao);
}
if (shader_ptr != &shader) {
#endif
vertex_buffer.bind();
elements_buffer.bind();
shader.bind(offset);
#ifdef GL_ARB_vertex_array_object
shader_ptr = &shader;
vertex_buffer_ptr = &vertex_buffer;
elements_buffer_ptr = &elements_buffer;
offset_ptr = offset;
} else if (vertex_buffer_ptr != &vertex_buffer) {
throw std::runtime_error("trying to bind VAO to another vertex buffer");
} else if (elements_buffer_ptr != &elements_buffer) {
throw std::runtime_error("trying to bind VAO to another elements buffer");
} else if (offset_ptr != offset) {
throw std::runtime_error("trying to bind VAO to another offset");
}
#endif
}
~VertexArrayObject() {
#ifdef GL_ARB_vertex_array_object
if (vao) {
glDeleteVertexArrays(1, &vao);
}
#endif
}
private:
#ifdef GL_ARB_vertex_array_object
GLuint vao = 0;
// For debug reasons, we're storing the bind information so that we can
// detect errors and report
void *shader_ptr = nullptr;
void *vertex_buffer_ptr = nullptr;
void *elements_buffer_ptr = nullptr;
char *offset_ptr = 0;
#endif
};
}
#endif
|
