    001package net.minecraft.world.gen;
    002
    003import java.util.Random;
    004import net.minecraft.block.Block;
    005import net.minecraft.util.MathHelper;
    006import net.minecraft.world.World;
    007import net.minecraft.world.biome.BiomeGenBase;
    008
    009public class MapGenCaves extends MapGenBase
    010{
    011    /**
    012     * Generates a larger initial cave node than usual. Called 25% of the time.
    013     */
    014    protected void generateLargeCaveNode(long par1, int par3, int par4, byte[] par5ArrayOfByte, double par6, double par8, double par10)
    015    {
    016        this.generateCaveNode(par1, par3, par4, par5ArrayOfByte, par6, par8, par10, 1.0F + this.rand.nextFloat() * 6.0F, 0.0F, 0.0F, -1, -1, 0.5D);
    017    }
    018
    019    /**
    020     * Generates a node in the current cave system recursion tree.
    021     */
    022    protected void generateCaveNode(long par1, int par3, int par4, byte[] par5ArrayOfByte, double par6, double par8, double par10, float par12, float par13, float par14, int par15, int par16, double par17)
    023    {
    024        double d4 = (double)(par3 * 16 + 8);
    025        double d5 = (double)(par4 * 16 + 8);
    026        float f3 = 0.0F;
    027        float f4 = 0.0F;
    028        Random random = new Random(par1);
    029
    030        if (par16 <= 0)
    031        {
    032            int j1 = this.range * 16 - 16;
    033            par16 = j1 - random.nextInt(j1 / 4);
    034        }
    035
    036        boolean flag = false;
    037
    038        if (par15 == -1)
    039        {
    040            par15 = par16 / 2;
    041            flag = true;
    042        }
    043
    044        int k1 = random.nextInt(par16 / 2) + par16 / 4;
    045
    046        for (boolean flag1 = random.nextInt(6) == 0; par15 < par16; ++par15)
    047        {
    048            double d6 = 1.5D + (double)(MathHelper.sin((float)par15 * (float)Math.PI / (float)par16) * par12 * 1.0F);
    049            double d7 = d6 * par17;
    050            float f5 = MathHelper.cos(par14);
    051            float f6 = MathHelper.sin(par14);
    052            par6 += (double)(MathHelper.cos(par13) * f5);
    053            par8 += (double)f6;
    054            par10 += (double)(MathHelper.sin(par13) * f5);
    055
    056            if (flag1)
    057            {
    058                par14 *= 0.92F;
    059            }
    060            else
    061            {
    062                par14 *= 0.7F;
    063            }
    064
    065            par14 += f4 * 0.1F;
    066            par13 += f3 * 0.1F;
    067            f4 *= 0.9F;
    068            f3 *= 0.75F;
    069            f4 += (random.nextFloat() - random.nextFloat()) * random.nextFloat() * 2.0F;
    070            f3 += (random.nextFloat() - random.nextFloat()) * random.nextFloat() * 4.0F;
    071
    072            if (!flag && par15 == k1 && par12 > 1.0F && par16 > 0)
    073            {
    074                this.generateCaveNode(random.nextLong(), par3, par4, par5ArrayOfByte, par6, par8, par10, random.nextFloat() * 0.5F + 0.5F, par13 - ((float)Math.PI / 2F), par14 / 3.0F, par15, par16, 1.0D);
    075                this.generateCaveNode(random.nextLong(), par3, par4, par5ArrayOfByte, par6, par8, par10, random.nextFloat() * 0.5F + 0.5F, par13 + ((float)Math.PI / 2F), par14 / 3.0F, par15, par16, 1.0D);
    076                return;
    077            }
    078
    079            if (flag || random.nextInt(4) != 0)
    080            {
    081                double d8 = par6 - d4;
    082                double d9 = par10 - d5;
    083                double d10 = (double)(par16 - par15);
    084                double d11 = (double)(par12 + 2.0F + 16.0F);
    085
    086                if (d8 * d8 + d9 * d9 - d10 * d10 > d11 * d11)
    087                {
    088                    return;
    089                }
    090
    091                if (par6 >= d4 - 16.0D - d6 * 2.0D && par10 >= d5 - 16.0D - d6 * 2.0D && par6 <= d4 + 16.0D + d6 * 2.0D && par10 <= d5 + 16.0D + d6 * 2.0D)
    092                {
    093                    int l1 = MathHelper.floor_double(par6 - d6) - par3 * 16 - 1;
    094                    int i2 = MathHelper.floor_double(par6 + d6) - par3 * 16 + 1;
    095                    int j2 = MathHelper.floor_double(par8 - d7) - 1;
    096                    int k2 = MathHelper.floor_double(par8 + d7) + 1;
    097                    int l2 = MathHelper.floor_double(par10 - d6) - par4 * 16 - 1;
    098                    int i3 = MathHelper.floor_double(par10 + d6) - par4 * 16 + 1;
    099
    100                    if (l1 < 0)
    101                    {
    102                        l1 = 0;
    103                    }
    104
    105                    if (i2 > 16)
    106                    {
    107                        i2 = 16;
    108                    }
    109
    110                    if (j2 < 1)
    111                    {
    112                        j2 = 1;
    113                    }
    114
    115                    if (k2 > 120)
    116                    {
    117                        k2 = 120;
    118                    }
    119
    120                    if (l2 < 0)
    121                    {
    122                        l2 = 0;
    123                    }
    124
    125                    if (i3 > 16)
    126                    {
    127                        i3 = 16;
    128                    }
    129
    130                    boolean flag2 = false;
    131                    int j3;
    132                    int k3;
    133
    134                    for (j3 = l1; !flag2 && j3 < i2; ++j3)
    135                    {
    136                        for (int l3 = l2; !flag2 && l3 < i3; ++l3)
    137                        {
    138                            for (int i4 = k2 + 1; !flag2 && i4 >= j2 - 1; --i4)
    139                            {
    140                                k3 = (j3 * 16 + l3) * 128 + i4;
    141
    142                                if (i4 >= 0 && i4 < 128)
    143                                {
    144                                    if (isOceanBlock(par5ArrayOfByte, k3, j3, i4, l3, par3, par4))
    145                                    {
    146                                        flag2 = true;
    147                                    }
    148
    149                                    if (i4 != j2 - 1 && j3 != l1 && j3 != i2 - 1 && l3 != l2 && l3 != i3 - 1)
    150                                    {
    151                                        i4 = j2;
    152                                    }
    153                                }
    154                            }
    155                        }
    156                    }
    157
    158                    if (!flag2)
    159                    {
    160                        for (j3 = l1; j3 < i2; ++j3)
    161                        {
    162                            double d12 = ((double)(j3 + par3 * 16) + 0.5D - par6) / d6;
    163
    164                            for (k3 = l2; k3 < i3; ++k3)
    165                            {
    166                                double d13 = ((double)(k3 + par4 * 16) + 0.5D - par10) / d6;
    167                                int j4 = (j3 * 16 + k3) * 128 + k2;
    168                                boolean flag3 = false;
    169
    170                                if (d12 * d12 + d13 * d13 < 1.0D)
    171                                {
    172                                    for (int k4 = k2 - 1; k4 >= j2; --k4)
    173                                    {
    174                                        double d14 = ((double)k4 + 0.5D - par8) / d7;
    175
    176                                        if (d14 > -0.7D && d12 * d12 + d14 * d14 + d13 * d13 < 1.0D)
    177                                        {
    178                                            if (isTopBlock(par5ArrayOfByte, j4, j3, k4, k3, par3, par4))
    179                                            {
    180                                                flag3 = true;
    181                                            }
    182
    183                                            digBlock(par5ArrayOfByte, j4, j3, k4, k3, par3, par4, flag3);
    184                                        }
    185
    186                                        --j4;
    187                                    }
    188                                }
    189                            }
    190                        }
    191
    192                        if (flag)
    193                        {
    194                            break;
    195                        }
    196                    }
    197                }
    198            }
    199        }
    200    }
    201
    202    /**
    203     * Recursively called by generate() (generate) and optionally by itself.
    204     */
    205    protected void recursiveGenerate(World par1World, int par2, int par3, int par4, int par5, byte[] par6ArrayOfByte)
    206    {
    207        int i1 = this.rand.nextInt(this.rand.nextInt(this.rand.nextInt(40) + 1) + 1);
    208
    209        if (this.rand.nextInt(15) != 0)
    210        {
    211            i1 = 0;
    212        }
    213
    214        for (int j1 = 0; j1 < i1; ++j1)
    215        {
    216            double d0 = (double)(par2 * 16 + this.rand.nextInt(16));
    217            double d1 = (double)this.rand.nextInt(this.rand.nextInt(120) + 8);
    218            double d2 = (double)(par3 * 16 + this.rand.nextInt(16));
    219            int k1 = 1;
    220
    221            if (this.rand.nextInt(4) == 0)
    222            {
    223                this.generateLargeCaveNode(this.rand.nextLong(), par4, par5, par6ArrayOfByte, d0, d1, d2);
    224                k1 += this.rand.nextInt(4);
    225            }
    226
    227            for (int l1 = 0; l1 < k1; ++l1)
    228            {
    229                float f = this.rand.nextFloat() * (float)Math.PI * 2.0F;
    230                float f1 = (this.rand.nextFloat() - 0.5F) * 2.0F / 8.0F;
    231                float f2 = this.rand.nextFloat() * 2.0F + this.rand.nextFloat();
    232
    233                if (this.rand.nextInt(10) == 0)
    234                {
    235                    f2 *= this.rand.nextFloat() * this.rand.nextFloat() * 3.0F + 1.0F;
    236                }
    237
    238                this.generateCaveNode(this.rand.nextLong(), par4, par5, par6ArrayOfByte, d0, d1, d2, f2, f, f1, 0, 0, 1.0D);
    239            }
    240        }
    241    }
    242
    243    protected boolean isOceanBlock(byte[] data, int index, int x, int y, int z, int chunkX, int chunkZ)
    244    {
    245        return data[index] == Block.waterMoving.blockID || data[index] == Block.waterStill.blockID;
    246    }
    247
    248    //Exception biomes to make sure we generate like vanilla
    249    private boolean isExceptionBiome(BiomeGenBase biome)
    250    {
    251        if (biome == BiomeGenBase.mushroomIsland) return true;
    252        if (biome == BiomeGenBase.beach) return true;
    253        if (biome == BiomeGenBase.desert) return true;
    254        return false;
    255    }
    256
    257    //Determine if the block at the specified location is the top block for the biome, we take into account
    258    //Vanilla bugs to make sure that we generate the map the same way vanilla does.
    259    private boolean isTopBlock(byte[] data, int index, int x, int y, int z, int chunkX, int chunkZ)
    260    {
    261        BiomeGenBase biome = worldObj.getBiomeGenForCoords(x + chunkX * 16, z + chunkZ * 16);
    262        return (isExceptionBiome(biome) ? data[index] == Block.grass.blockID : data[index] == biome.topBlock);
    263    }
    264
    265    /**
    266     * Digs out the current block, default implementation removes stone, filler, and top block
    267     * Sets the block to lava if y is less then 10, and air other wise.
    268     * If setting to air, it also checks to see if we've broken the surface and if so
    269     * tries to make the floor the biome's top block
    270     *
    271     * @param data Block data array
    272     * @param index Pre-calculated index into block data
    273     * @param x local X position
    274     * @param y local Y position
    275     * @param z local Z position
    276     * @param chunkX Chunk X position
    277     * @param chunkZ Chunk Y position
    278     * @param foundTop True if we've encountered the biome's top block. Ideally if we've broken the surface.
    279     */
    280    protected void digBlock(byte[] data, int index, int x, int y, int z, int chunkX, int chunkZ, boolean foundTop)
    281    {
    282        BiomeGenBase biome = worldObj.getBiomeGenForCoords(x + chunkX * 16, z + chunkZ * 16);
    283        int top    = (isExceptionBiome(biome) ? Block.grass.blockID : biome.topBlock);
    284        int filler = (isExceptionBiome(biome) ? Block.dirt.blockID  : biome.fillerBlock);
    285        int block  = data[index];
    286
    287        if (block == Block.stone.blockID || block == filler || block == top)
    288        {
    289            if (y < 10)
    290            {
    291                data[index] = (byte)Block.lavaMoving.blockID;
    292            }
    293            else
    294            {
    295                data[index] = 0;
    296
    297                if (foundTop && data[index - 1] == filler)
    298                {
    299                    data[index - 1] = (byte)top;
    300                }
    301            }
    302        }
    303    }
    304}