TempleLayer.java

package amidst.map.layers;

import java.util.Arrays;
import java.util.List;
import java.util.Random;

import amidst.Options;
import amidst.logging.Log;
import amidst.map.Fragment;
import amidst.map.IconLayer;
import amidst.map.MapObjectDesertTemple;
import amidst.map.MapObjectJungleTemple;
import amidst.map.MapObjectWitchHut;
import amidst.minecraft.Biome;
import amidst.minecraft.MinecraftUtil;
import amidst.version.VersionInfo;

public class TempleLayer extends IconLayer {
	public static List<Biome> validBiomes;
	private Random random = new Random();
	
	public TempleLayer() {
		validBiomes = getValidBiomes();
	}
	
	@Override
	public boolean isVisible() {
		return Options.instance.showTemples.get();		
	}
	
	@Override
	public void generateMapObjects(Fragment frag) {
		int size = Fragment.SIZE >> 4;
		for (int x = 0; x < size; x++) {
			for (int y = 0; y < size; y++) {
				int chunkX = x + frag.getChunkX();
				int chunkY = y + frag.getChunkY();
				Biome chunkBiome = checkChunk(chunkX, chunkY);
				if (chunkBiome != null) {
					
					if (chunkBiome == Biome.swampland) {
						frag.addObject(new MapObjectWitchHut(x << 4, y << 4).setParent(this));
					} else if (chunkBiome.name.contains("Jungle")) {
						frag.addObject(new MapObjectJungleTemple(x << 4, y << 4).setParent(this));
					} else if (chunkBiome.name.contains("Desert")) {					
						frag.addObject(new MapObjectDesertTemple(x << 4, y << 4).setParent(this));
					} else {			
						Log.e("No known structure for this biome type. checkChunk() may be faulting.");
					}
				}
			}
		}
	}
	
	public List<Biome> getValidBiomes() {
		Biome[] validBiomes;
		
		if (MinecraftUtil.getVersion().isAtLeast(VersionInfo.V1_4_2)) {
			validBiomes = new Biome[] {
				Biome.desert,
				Biome.desertHills,
				Biome.jungle,
				Biome.jungleHills,
				Biome.swampland
			};
		} else if (MinecraftUtil.getVersion().isAtLeast(VersionInfo.V12w22a)) {
			validBiomes = new Biome[] {
				Biome.desert,
				Biome.desertHills,
				Biome.jungle
			};
		} else {
			validBiomes = new Biome[] {
				Biome.desert,
				Biome.desertHills
			};
		}
		
		return Arrays.asList(validBiomes);
	}
	
	/**
	 * @return null if there is no structure in the chunk, otherwise 
	 * returns the biome (from validBiomes) that determines the type
	 * of structure.
	 */
	public Biome checkChunk(int chunkX, int chunkY) {

		Biome result = null;
		
		int maxDistanceBetweenScatteredFeatures = 32;
		int minDistanceBetweenScatteredFeatures = 8;
		
		int k = chunkX;
		int m = chunkY;
		if (chunkX < 0) chunkX -= maxDistanceBetweenScatteredFeatures - 1;
		if (chunkY < 0) chunkY -= maxDistanceBetweenScatteredFeatures - 1;
		
		int n = chunkX / maxDistanceBetweenScatteredFeatures;
		int i1 = chunkY / maxDistanceBetweenScatteredFeatures;
		long l1 = n * 341873128712L + i1 * 132897987541L + Options.instance.seed + 14357617;
		random.setSeed(l1);
		n *= maxDistanceBetweenScatteredFeatures;
		i1 *= maxDistanceBetweenScatteredFeatures;
		n += random.nextInt(maxDistanceBetweenScatteredFeatures - minDistanceBetweenScatteredFeatures);
		i1 += random.nextInt(maxDistanceBetweenScatteredFeatures - minDistanceBetweenScatteredFeatures);

		if (k == n && m == i1) {
			// This is a potential feature biome			
			
			// Since the structure-size that would be passed to MinecraftUtil.isValidBiome() 
			// is 0, we can use MinecraftUtil.getBiomeAt() here instead, which tells us what kind of 
			// structure it is.
			Biome chunkBiome = MinecraftUtil.getBiomeAt(k * 16 + 8, m * 16 + 8);
			if (validBiomes.contains(chunkBiome)) result = chunkBiome;
		}	
		return result;
	}
}