ChunkGenerator.cpp

// This function looks up in the vertice table wheter a vertice at that position already exists
// - If yes, return the vertice index
// - If no, create a new vertice and return the created vertice index
//
// @param cfg: Pointer to a chunkConfig struct
// @param w_vertex: Pointer to the vertex writer
// @param w_texcoord: Pointer to the texcoord writer
// @param x: x position of the vertice
// @param y: y position of the vertice
inline VERTICE_INDEX GetOrCreateVertice(float x, float y, ChunkGenerator::chunkConfig *cfg) 
{
    int x_pos = int((x*POSARR_ADJ_F) + 0.5f);
	int y_pos = int((y*POSARR_ADJ_F) + 0.5f);	

	int dict_index = x_pos + (y_pos * (cfg->subdivisions * POSARR_ADJ));

	VERTICE_INDEX dict_entry = cfg->vertice_pool.vertice_dict[dict_index];
	VERTICE_INDEX current_index = cfg->vertice_pool.current_vertice_index;

	if (dict_entry >= 0 && dict_entry < 65535 && current_index > 0)
		return dict_entry;
	
	LVecBase3f* offset		= cfg->base_position;
	LVecBase2f* dim			= cfg->dimensions;
	LVecBase2f* tex_offset	= cfg->texture_offset;
	LVecBase2f* tex_scale	= cfg->texture_scale;

	int pool_index = ((int)current_index) * 5;
	
	// instead of calling add_data3f we store all data in array and cast it later to binary
	// Format: v.x, v.y, v.z, t.x, t.y

	float base_scale = 1.0 / (cfg->subdivisions_f-1.0);
	//float base_scale = 1.0;

	cfg->vertice_pool.vertice_array[pool_index+0] = offset->get_x() + (x * base_scale * dim->get_x());
	cfg->vertice_pool.vertice_array[pool_index+1] = offset->get_y() + (y * base_scale * dim->get_y());
	cfg->vertice_pool.vertice_array[pool_index+2] = offset->get_z();
	cfg->vertice_pool.vertice_array[pool_index+3] = tex_offset->get_x() + (x * tex_scale->get_x() * base_scale);
	cfg->vertice_pool.vertice_array[pool_index+4] = tex_offset->get_y() + (y * tex_scale->get_y() * base_scale);

	//printf("Vertice(%f, %f, index=%i)\n", x,y,current_index);

	cfg->vertice_pool.vertice_dict[dict_index] = current_index;
	cfg->vertice_pool.current_vertice_index++;
	return current_index;
}