4jcraft/Minecraft.World/WorldGen/Features/SwampTreeFeature.cpp

#include "../../Platform/stdafx.h"
#include "SwampTreeFeature.h"
#include "../../Headers/net.minecraft.world.level.h"
#include "../../Headers/net.minecraft.world.level.tile.h"
#include "../../Util/JavaMath.h"

bool SwampTreeFeature::place(Level* level, Random* random, int x, int y,
                             int z) {
    int treeHeight = random->nextInt(4) + 5;
    while (level->getMaterial(x, y - 1, z) == Material::water) y--;

    bool free = true;
    if (y < 1 || y + treeHeight + 1 > Level::genDepth) return false;

    // 4J Stu Added to stop tree features generating areas previously place by
    // game rule generation
    if (app.getLevelGenerationOptions() != NULL) {
        LevelGenerationOptions* levelGenOptions =
            app.getLevelGenerationOptions();
        bool intersects = levelGenOptions->checkIntersects(
            x - 3, y - 1, z - 3, x + 3, y + treeHeight, z + 3);
        if (intersects) {
            // app.DebugPrintf("Skipping reeds feature generation as it overlaps
            // a game rule structure\n");
            return false;
        }
    }

    for (int yy = y; yy <= y + 1 + treeHeight; yy++) {
        int r = 1;
        if (yy == y) r = 0;
        if (yy >= y + 1 + treeHeight - 2) r = 3;
        for (int xx = x - r; xx <= x + r && free; xx++) {
            for (int zz = z - r; zz <= z + r && free; zz++) {
                if (yy >= 0 && yy < Level::genDepth) {
                    int tt = level->getTile(xx, yy, zz);
                    if (tt != 0 && tt != Tile::leaves_Id) {
                        if (tt == Tile::calmWater_Id || tt == Tile::water_Id) {
                            if (yy > y) free = false;
                        } else {
                            free = false;
                        }
                    }
                } else {
                    free = false;
                }
            }
        }
    }

    if (!free) return false;

    int belowTile = level->getTile(x, y - 1, z);
    if ((belowTile != Tile::grass_Id && belowTile != Tile::dirt_Id) ||
        y >= Level::genDepth - treeHeight - 1)
        return false;

    placeBlock(level, x, y - 1, z, Tile::dirt_Id);

    for (int yy = y - 3 + treeHeight; yy <= y + treeHeight; yy++) {
        int yo = yy - (y + treeHeight);
        int offs = 2 - yo / 2;
        for (int xx = x - offs; xx <= x + offs; xx++) {
            int xo = xx - (x);
            for (int zz = z - offs; zz <= z + offs; zz++) {
                int zo = zz - (z);
                if (abs(xo) == offs && abs(zo) == offs &&
                    (random->nextInt(2) == 0 || yo == 0))
                    continue;
                if (!Tile::solid[level->getTile(xx, yy, zz)])
                    placeBlock(level, xx, yy, zz, Tile::leaves_Id);
            }
        }
    }

    for (int hh = 0; hh < treeHeight; hh++) {
        int t = level->getTile(x, y + hh, z);
        if (t == 0 || t == Tile::leaves_Id || t == Tile::water_Id ||
            t == Tile::calmWater_Id)
            placeBlock(level, x, y + hh, z, Tile::treeTrunk_Id);
    }

    for (int yy = y - 3 + treeHeight; yy <= y + treeHeight; yy++) {
        int yo = yy - (y + treeHeight);
        int offs = 2 - yo / 2;
        for (int xx = x - offs; xx <= x + offs; xx++) {
            for (int zz = z - offs; zz <= z + offs; zz++) {
                if (level->getTile(xx, yy, zz) == Tile::leaves_Id) {
                    if (random->nextInt(4) == 0 &&
                        level->getTile(xx - 1, yy, zz) == 0) {
                        addVine(level, xx - 1, yy, zz, VineTile::VINE_EAST);
                    }
                    if (random->nextInt(4) == 0 &&
                        level->getTile(xx + 1, yy, zz) == 0) {
                        addVine(level, xx + 1, yy, zz, VineTile::VINE_WEST);
                    }
                    if (random->nextInt(4) == 0 &&
                        level->getTile(xx, yy, zz - 1) == 0) {
                        addVine(level, xx, yy, zz - 1, VineTile::VINE_SOUTH);
                    }
                    if (random->nextInt(4) == 0 &&
                        level->getTile(xx, yy, zz + 1) == 0) {
                        addVine(level, xx, yy, zz + 1, VineTile::VINE_NORTH);
                    }
                }
            }
        }
    }
    return true;
}

void SwampTreeFeature::addVine(Level* level, int xx, int yy, int zz, int dir) {
    placeBlock(level, xx, yy, zz, Tile::vine_Id, dir);
    int maxDir = 4;
    while (level->getTile(xx, --yy, zz) == 0 && maxDir > 0) {
        placeBlock(level, xx, yy, zz, Tile::vine_Id, dir);
        maxDir--;
    }
}