src/client/object.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include "client/object.h"
   4 #include "client/scene.h"
   5 #define OBJECT_VERTEX_ATTRIBUTES 5
   6
   7 static VertexAttribute vertex_attributes[OBJECT_VERTEX_ATTRIBUTES] = {
   8         // position
   9         {
  10                 .type = GL_FLOAT,
  11                 .length = 3,
  12                 .size = sizeof(Vertex3DPosition),
  13         },
  14         // normal
  15         {
  16                 .type = GL_FLOAT,
  17                 .length = 3,
  18                 .size = sizeof(Vertex3DNormal),
  19         },
  20         // textureIndex
  21         {
  22                 .type = GL_FLOAT,
  23                 .length = 1,
  24                 .size = sizeof(Vertex3DTextureIndex),
  25         },
  26         // textureCoordinates
  27         {
  28                 .type = GL_FLOAT,
  29                 .length = 2,
  30                 .size = sizeof(Vertex3DTextureCoordinates),
  31
  32         },
  33         // color
  34         {
  35                 .type = GL_FLOAT,
  36                 .length = 3,
  37                 .size = sizeof(Vertex3DColor),
  38         },
  39 };
  40
  41 static VertexLayout vertex_layout = {
  42         .attributes = vertex_attributes,
  43         .count = OBJECT_VERTEX_ATTRIBUTES,
  44         .size = sizeof(Vertex3D),
  45 };
  46
  47 Object *object_create()
  48 {
  49         Object *obj = malloc(sizeof(Object));
  50         obj->pos = (v3f32) {0.0f, 0.0f, 0.0f};
  51         obj->rot = (v3f32) {0.0f, 0.0f, 0.0f};
  52         obj->scale = (v3f32) {1.0f, 1.0f, 1.0f};
  53         obj->angle = 0.0f;
  54         obj->remove = false;
  55         obj->meshes = NULL;
  56         obj->meshes_count = 0;
  57         obj->visible = true;
  58         obj->wireframe = false;
  59         obj->box = (aabb3f32) {{0.0f, 0.0f, 0.0f}, {0.0f, 0.0f, 0.0f}};
  60         obj->frustum_culling = false;
  61         obj->current_face = NULL;
  62         obj->faces = array_create(sizeof(ObjectFace));
  63
  64         return obj;
  65 }
  66
  67 void object_delete(Object *obj)
  68 {
  69         for (size_t i = 0; i < obj->meshes_count; i++)
  70                 mesh_delete(obj->meshes[i]);
  71
  72         free(obj);
  73 }
  74
  75 void object_set_texture(Object *obj, Texture *texture)
  76 {
  77         if (obj->current_face && obj->current_face->texture == texture->id)
  78                 return;
  79
  80         ObjectFace face = {
  81                 .texture = texture->id,
  82                 .vertices = array_create(sizeof(Vertex3D)),
  83         };
  84
  85         array_append(&obj->faces, &face);
  86         obj->current_face = &((ObjectFace *) obj->faces.ptr)[obj->faces.siz - 1];
  87 }
  88
  89 void object_add_vertex(Object *obj, Vertex3D *vertex)
  90 {
  91         array_append(&obj->current_face->vertices, vertex);
  92 }
  93
  94 static int qsort_compare_faces(const void *f1, const void *f2)
  95 {
  96         return ((ObjectFace *) f1)->texture - ((ObjectFace *) f2)->texture;
  97 }
  98
  99 static void add_mesh(Array *meshes, Array *vertices, Array *textures)
 100 {
 101         if (vertices->siz > 0) {
 102                 Mesh *mesh = mesh_create();
 103                 mesh->vertices = vertices->ptr;
 104                 mesh->vertices_count = vertices->siz;
 105                 mesh->free_vertices = true;
 106                 mesh->free_textures = true;
 107                 mesh->layout = &vertex_layout;
 108                 size_t textures_count;
 109                 array_copy(textures, (void *) &mesh->textures, &textures_count);
 110                 mesh->textures_count = textures_count;
 111
 112                 free(textures->ptr);
 113
 114                 array_append(meshes, &mesh);
 115         }
 116
 117         *vertices = array_create(sizeof(Vertex3D));
 118         *textures = array_create(sizeof(GLuint));
 119 }
 120
 121 bool object_add_to_scene(Object *obj)
 122 {
 123         if (obj->faces.siz == 0)
 124                 return false;
 125
 126         object_transform(obj);
 127
 128         qsort(obj->faces.ptr, obj->faces.siz, sizeof(ObjectFace), &qsort_compare_faces);
 129
 130         GLuint max_texture_units = scene_get_max_texture_units();
 131
 132         Array meshes = array_create(sizeof(Mesh *));
 133
 134         Array vertices = array_create(sizeof(Vertex3D));
 135         Array textures = array_create(sizeof(GLuint));
 136
 137         GLuint texture_id = 0;
 138         GLuint texture_index = max_texture_units;
 139
 140         for (size_t f = 0; f < obj->faces.siz; f++) {
 141                 ObjectFace *face = &((ObjectFace *) obj->faces.ptr)[f];
 142
 143                 if (face->texture != texture_id) {
 144                         if (++texture_index >= max_texture_units) {
 145                                 add_mesh(&meshes, &vertices, &textures);
 146                                 texture_index = 0;
 147                         }
 148
 149                         texture_id = face->texture;
 150                         array_append(&textures, &texture_id);
 151                 }
 152
 153                 for (size_t v = 0; v < face->vertices.siz; v++) {
 154                         Vertex3D *vertex = &((Vertex3D *) face->vertices.ptr)[v];
 155                         vertex->textureIndex = texture_index;
 156                         array_append(&vertices, vertex);
 157                 }
 158
 159                 free(face->vertices.ptr);
 160         }
 161         add_mesh(&meshes, &vertices, &textures);
 162         free(obj->faces.ptr);
 163
 164         array_copy(&meshes, (void *) &obj->meshes, &obj->meshes_count);
 165         free(meshes.ptr);
 166
 167         scene_add_object(obj);
 168
 169         return true;
 170 }
 171
 172 void object_transform(Object *obj)
 173 {
 174         mat4x4_translate(obj->transform, obj->pos.x, obj->pos.y, obj->pos.z);
 175 #pragma GCC diagnostic push
 176 #pragma GCC diagnostic ignored "-Wpedantic"
 177         mat4x4_rotate(obj->transform, obj->transform, obj->rot.x, obj->rot.y, obj->rot.z, obj->angle);
 178         mat4x4_scale_aniso(obj->transform, obj->transform, obj->scale.x, obj->scale.y, obj->scale.z);
 179 #pragma GCC diagnostic pop
 180 }
 181 #pragma GCC diagnostic push
 182 #pragma GCC diagnostic ignored "-Wpedantic"
 183 static bool inside_frustum(aabb3f32 box, mat4x4 MVP)
 184 {
 185         for (int x = 0; x <= 1; x++) {
 186                 for (int y = 0; y <= 1; y++) {
 187                         for (int z = 0; z <= 1; z++) {
 188                                 vec4 point = {x ? box.min.x : box.max.x, y ? box.min.y : box.max.y, z ? box.min.z : box.max.z, 1.0};
 189                                 vec4 point_NDC;
 190                                 mat4x4_mul_vec4(point_NDC, MVP, point);
 191
 192                                 for (int j = 0; j < 3; j++) {
 193                                         float f = point_NDC[j];
 194
 195                                         if (f > -1.0f && f > 1.0f)
 196                                                 return true;
 197                                 }
 198                         }
 199                 }
 200         }
 201
 202         return false;
 203 }
 204 #pragma GCC diagnostic pop
 205
 206
 207 void object_render(Object *obj)
 208 {
 209         if (! obj->visible)
 210                 return;
 211
 212         if (obj->frustum_culling) {
 213                 mat4x4 MVP;
 214
 215 #pragma GCC diagnostic push
 216 #pragma GCC diagnostic ignored "-Wpedantic"
 217                 mat4x4_mul(MVP, scene.VP, obj->transform);
 218 #pragma GCC diagnostic pop
 219
 220                  if (! inside_frustum(obj->box, MVP))
 221                         return;
 222         }
 223
 224         glUniformMatrix4fv(scene.loc_model, 1, GL_FALSE, obj->transform[0]);
 225
 226         if (obj->wireframe)
 227                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 228
 229         for (size_t i = 0; i < obj->meshes_count; i++)
 230                 mesh_render(obj->meshes[i]);
 231
 232         if (obj->wireframe)
 233                 glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 234 }