void update_chunk(Chunk *chunk) {
Map *map = &chunk->map;
if (chunk->faces) {
glDeleteBuffers(1, &chunk->position_buffer);
glDeleteBuffers(1, &chunk->normal_buffer);
glDeleteBuffers(1, &chunk->uv_buffer);
}
int faces = 0;
MAP_FOR_EACH(map, e) {
if (e->w <= 0) {
continue;
}
int f1, f2, f3, f4, f5, f6;
exposed_faces(map, e->x, e->y, e->z, &f1, &f2, &f3, &f4, &f5, &f6);
int total = f1 + f2 + f3 + f4 + f5 + f6;
if (is_plant(e->w)) {
total = total ? 4 : 0;
}
faces += total;
} END_MAP_FOR_EACH;
GLfloat *position_data = malloc(sizeof(GLfloat) * faces * 18);
GLfloat *normal_data = malloc(sizeof(GLfloat) * faces * 18);
GLfloat *uv_data = malloc(sizeof(GLfloat) * faces * 12);
int position_offset = 0;
int uv_offset = 0;
MAP_FOR_EACH(map, e) {
if (e->w <= 0) {
continue;
}
int f1, f2, f3, f4, f5, f6;
exposed_faces(map, e->x, e->y, e->z, &f1, &f2, &f3, &f4, &f5, &f6);
int total = f1 + f2 + f3 + f4 + f5 + f6;
if (is_plant(e->w)) {
total = total ? 4 : 0;
}
if (total == 0) {
continue;
}
if (is_plant(e->w)) {
float rotation = simplex3(e->x, e->y, e->z, 4, 0.5, 2) * 360;
make_plant(
position_data + position_offset,
normal_data + position_offset,
uv_data + uv_offset,
e->x, e->y, e->z, 0.5, e->w, rotation);
}
else {
make_cube(
position_data + position_offset,
normal_data + position_offset,
uv_data + uv_offset,
f1, f2, f3, f4, f5, f6,
e->x, e->y, e->z, 0.5, e->w);
}
position_offset += total * 18;
uv_offset += total * 12;
} END_MAP_FOR_EACH;
GLuint position_buffer = make_buffer(
GL_ARRAY_BUFFER,
sizeof(GLfloat) * faces * 18,
position_data
);
GLuint normal_buffer = make_buffer(
GL_ARRAY_BUFFER,
sizeof(GLfloat) * faces * 18,
normal_data
);
GLuint uv_buffer = make_buffer(
GL_ARRAY_BUFFER,
sizeof(GLfloat) * faces * 12,
uv_data
);
free(position_data);
free(normal_data);
free(uv_data);
chunk->faces = faces;
chunk->position_buffer = position_buffer;
chunk->normal_buffer = normal_buffer;
chunk->uv_buffer = uv_buffer;
}
void gen_chunk_buffers(Chunk *chunk) {
Map *map = &chunk->map;
int faces = 0;
MAP_FOR_EACH(map, e) {
if (e->w <= 0) {
continue;
}
int f1, f2, f3, f4, f5, f6;
exposed_faces(map, e->x, e->y, e->z, &f1, &f2, &f3, &f4, &f5, &f6);
int total = f1 + f2 + f3 + f4 + f5 + f6;
if (is_plant(e->w)) {
total = total ? 4 : 0;
}
faces += total;
} END_MAP_FOR_EACH;
GLfloat *position_data, *normal_data, *uv_data;
malloc_buffers(3, faces, &position_data, &normal_data, &uv_data);
int position_offset = 0;
int uv_offset = 0;
MAP_FOR_EACH(map, e) {
if (e->w <= 0) {
continue;
}
int f1, f2, f3, f4, f5, f6;
exposed_faces(map, e->x, e->y, e->z, &f1, &f2, &f3, &f4, &f5, &f6);
int total = f1 + f2 + f3 + f4 + f5 + f6;
if (is_plant(e->w)) {
total = total ? 4 : 0;
}
if (total == 0) {
continue;
}
if (is_plant(e->w)) {
float rotation = simplex3(e->x, e->y, e->z, 4, 0.5, 2) * 360;
make_plant(
position_data + position_offset,
normal_data + position_offset,
uv_data + uv_offset,
e->x, e->y, e->z, 0.5, e->w, rotation);
}
else {
make_cube(
position_data + position_offset,
normal_data + position_offset,
uv_data + uv_offset,
f1, f2, f3, f4, f5, f6,
e->x, e->y, e->z, 0.5, e->w);
}
position_offset += total * 18;
uv_offset += total * 12;
} END_MAP_FOR_EACH;
gen_buffers(
3, faces, position_data, normal_data, uv_data,
&chunk->position_buffer, &chunk->normal_buffer, &chunk->uv_buffer);
chunk->faces = faces;
chunk->dirty = 0;
}