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
|
#include "mesh.h"
honey_result honey_mesh_new(honey_mesh* mesh,
float* vertices,
unsigned int n_vertices,
unsigned int n_attributes,
unsigned int* attribute_sizes,
unsigned int* indices,
unsigned int n_indices) {
if (vertices == NULL || n_vertices == 0) {
return HONEY_MESH_BAD_VERTEX_DATA;
}
if (indices == NULL || n_indices == 0) {
return HONEY_MESH_BAD_INDEX_DATA;
}
unsigned int vertex_size = 0;
for (int i=0; i<n_attributes; i++) {
vertex_size += attribute_sizes[i];
}
(*mesh).vertices = malloc(vertex_size*n_vertices * sizeof(float));
if ((*mesh).vertices == NULL) {
return HONEY_MEMORY_ALLOCATION_ERROR;
}
memcpy((*mesh).vertices, vertices, vertex_size*n_vertices*sizeof(float));
(*mesh).indices = malloc(n_indices * sizeof(unsigned int));
if ((*mesh).indices == NULL) {
return HONEY_MEMORY_ALLOCATION_ERROR;
}
memcpy((*mesh).indices, indices, n_indices * sizeof(unsigned int));
(*mesh).n_vertices = n_vertices;
(*mesh).n_indices = n_indices;
glGenVertexArrays(1, &((*mesh).vertex_array));
glGenBuffers(1, &((*mesh).vertex_buffer));
glGenBuffers(1, &((*mesh).element_buffer));
glBindVertexArray((*mesh).vertex_array);
glBindBuffer(GL_ARRAY_BUFFER, (*mesh).vertex_buffer);
glBufferData(GL_ARRAY_BUFFER, vertex_size*n_vertices*sizeof(float), (*mesh).vertices, GL_STATIC_DRAW);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, (*mesh).element_buffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, n_indices * sizeof(unsigned int), (*mesh).indices, GL_STATIC_DRAW);
/* set up vertex attributes */
unsigned int offset = 0;
for (int i=0; i<n_attributes; i++) {
glEnableVertexAttribArray(i);
glVertexAttribPointer(i,
attribute_sizes[i],
GL_FLOAT,
GL_FALSE,
vertex_size*sizeof(float),
(void*) (offset*sizeof(float)));
offset += attribute_sizes[i];
}
glBindVertexArray(0);
return HONEY_OK;
}
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
void honey_mesh_draw(honey_mesh mesh, honey_shader shader) {
honey_shader_use(shader);
glBindVertexArray(mesh.vertex_array);
glDrawElements(GL_TRIANGLES, mesh.n_indices, GL_UNSIGNED_INT, 0);
glBindVertexArray(0);
}
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
void honey_mesh_delete(honey_mesh mesh) {
free(mesh.vertices);
free(mesh.indices);
glDeleteVertexArrays(1, &(mesh.vertex_array));
glDeleteBuffers(1, &(mesh.vertex_buffer));
glDeleteBuffers(1, &(mesh.element_buffer));
}
|
