UwUGL/mappers/tilemapper.cpp

#pragma once

#include <stdint.h>

#include "../datatypes.cpp"
#include "../helpers.cpp"
#include "mapperbase.cpp"

namespace UwU {
  class TileMapper : public MapperBase<TileMapper> { // not actually tilemapping yet
    public:
      TileMapper() {
        this->tileMap = new uint16_t[16384]; // the map of tile positions 128x128 8x8 tiles from a 512x512 bitmap space
      }
      uint16_t* tileMap;

      Coord2 map(uint16_t x0, uint16_t y0, uint16_t x, uint16_t y) {
        uint16_t u0 = x - x0;
        uint16_t v0 = y - y0;
        // returns uv coordinates that point to a specific pixel of a specific tile on a tilesheet buffer
        uint16_t mapX = (u0 & 0x03f8) >> 3;
        uint16_t mapY = (v0 & 0x03f8) << 4;
        uint16_t tileIndex = tileMap[mapY + mapX];
        uint16_t u = (tileIndex & 0x003f) << 3;
        u += (u0 & 0x0007);
        uint16_t v = (tileIndex & 0x0fc0) >> 3;
        v += (v0 & 0x0007);
        return Coord2(u, v);
     }
  };
}