SurfaceFormat::ColorGrid renderWorldByPurity(const World &world) {
    return renderWorld(world, [](const Tile& t) {
      if (t.hasTile) {
        const Properties::TileProperty &tprop = t.getTileProperties();
        if (tprop.givesItem == Properties::GivesItem::ALWAYS) {
          return tprop.attributes.biome & (int) Properties::Biome::CRIMSON
                 ? SurfaceFormat::RGBA(255, 0, 0, 255)
                 : tprop.attributes.biome & (int) Properties::Biome::CORRUPTION
                   ? SurfaceFormat::RGBA(128, 0, 255, 255)
                   : tprop.attributes.biome & (int) Properties::Biome::HALLOW
                     ? SurfaceFormat::RGBA(64, 128, 255, 255)
                     : SurfaceFormat::RGBA(32, 200, 64, 255);
        }
      }
      if (t.liquidAmount > 0 && t.liquidType != LiquidType::NONE) {
        return t.liquidType == LiquidType::WATER
               ? SurfaceFormat::RGBA(0, 0, 255, t.liquidAmount * 255 / 8)
               : t.liquidType == LiquidType::HONEY
                   ? SurfaceFormat::RGBA(255, 255, 0, t.liquidAmount * 255 / 8)
                   : SurfaceFormat::RGBA(255, 0, 0, t.liquidAmount * 255 / 8);
      }
      return SurfaceFormat::RGBA(255, 255, 255, 255);
    });
  }

// ==============================================================================
// Select lines 15-22, Refactor—→Extract method. Result:
// ==============================================================================

  SurfaceFormat::RGBA getLiquidColor(const Tile &t);

  SurfaceFormat::ColorGrid renderWorldByPurity(const World &world) {
    return renderWorld(world, [](const Tile& t) {
      if (t.hasTile) {
        const Properties::TileProperty &tprop = t.getTileProperties();
        if (tprop.givesItem == Properties::GivesItem::ALWAYS) {
          return tprop.attributes.biome & (int) Properties::Biome::CRIMSON
                 ? SurfaceFormat::RGBA(255, 0, 0, 255)
                 : tprop.attributes.biome & (int) Properties::Biome::CORRUPTION
                   ? SurfaceFormat::RGBA(128, 0, 255, 255)
                   : tprop.attributes.biome & (int) Properties::Biome::HALLOW
                     ? SurfaceFormat::RGBA(64, 128, 255, 255)
                     : SurfaceFormat::RGBA(32, 200, 64, 255);
        }
      }
      return getLiquidColor(t);
    });
  }

  SurfaceFormat::ColorGrid getLiquidColor(const Tile &t) {
    if (t.liquidAmount > 0 && t.liquidType != LiquidType::NONE) {
        return t.liquidType == LiquidType::WATER
               ? this->RGBA(0, 0, 255, t.liquidAmount * 255 / 8)
               : t.liquidType == LiquidType::HONEY
                   ? this->RGBA(255, 255, 0, t.liquidAmount * 255 / 8)
                   : this->RGBA(255, 0, 0, t.liquidAmount * 255 / 8);
      }
    return this->RGBA(255, 255, 255, 255);
  }