Function GetTilePixelSlopeOutsideMap

src/tile_map.cpp:78–87

* Return the slope of a given tile, also for tiles outside the map (virtual "black" tiles). * * @param x X coordinate of the tile to compute slope of, may be outside the map. * @param y Y coordinate of the tile to compute slope of, may be outside the map. * @param h If not \c nullptr, pointer to storage of z height. * @return Slope of the tile, except for the HALFTILE part, and the z height o

 * @return Slope of the tile, except for the HALFTILE part, and the z height of the tile.
 */
std::tuple<Slope, int> GetTilePixelSlopeOutsideMap(int x, int y)
{
	int hnorth = TileHeightOutsideMap(x,     y);     // N corner.
	int hwest  = TileHeightOutsideMap(x + 1, y);     // W corner.
	int heast  = TileHeightOutsideMap(x,     y + 1); // E corner.
	int hsouth = TileHeightOutsideMap(x + 1, y + 1); // S corner.

	auto [slope, h] = GetTileSlopeGivenHeight(hnorth, hwest, heast, hsouth);
	return {slope, h * TILE_HEIGHT};
}

/**
 * Check if a given tile is flat