src/client/mesh.c

   1 #include <stddef.h>
   2 #include <stdlib.h>
   3 #include "client/gl_debug.h"
   4 #include "client/mesh.h"
   5
   6 // upload data to GPU (only done once)
   7 void mesh_upload(Mesh *mesh)
   8 {
   9         glGenVertexArrays(1, &mesh->vao); GL_DEBUG
  10         glGenBuffers(1, &mesh->vbo); GL_DEBUG
  11
  12         glBindVertexArray(mesh->vao); GL_DEBUG
  13         glBindBuffer(GL_ARRAY_BUFFER, mesh->vbo); GL_DEBUG
  14
  15         glBufferData(GL_ARRAY_BUFFER, mesh->count * mesh->layout->size,
  16                 mesh->data, GL_STATIC_DRAW); GL_DEBUG
  17
  18         size_t offset = 0;
  19         for (GLuint i = 0; i < mesh->layout->count; i++) {
  20                 VertexAttribute *attrib = &mesh->layout->attributes[i];
  21
  22                 glVertexAttribPointer(i, attrib->length, attrib->type, GL_FALSE,
  23                         mesh->layout->size, (GLvoid *) offset); GL_DEBUG
  24                 glEnableVertexAttribArray(i); GL_DEBUG
  25
  26                 offset += attrib->size;
  27         }
  28
  29         glBindBuffer(GL_ARRAY_BUFFER, 0); GL_DEBUG
  30         glBindVertexArray(0); GL_DEBUG
  31
  32         if (mesh->free_data)
  33                 free(mesh->data);
  34
  35         mesh->data = NULL;
  36 }
  37
  38 void mesh_render(Mesh *mesh)
  39 {
  40         if (mesh->data)
  41                 mesh_upload(mesh);
  42
  43         // render
  44         glBindVertexArray(mesh->vao); GL_DEBUG
  45         glDrawArrays(GL_TRIANGLES, 0, mesh->count); GL_DEBUG
  46 }
  47
  48 void mesh_destroy(Mesh *mesh)
  49 {
  50         if (mesh->data && mesh->free_data)
  51                 free(mesh->data);
  52
  53         if (mesh->vao) {
  54                 glDeleteVertexArrays(1, &mesh->vao); GL_DEBUG
  55         }
  56
  57         if (mesh->vbo) {
  58                 glDeleteBuffers(1, &mesh->vbo); GL_DEBUG
  59         }
  60
  61         mesh->vao = mesh->vbo = 0;
  62 }