Examples with SpiralIterable org.terasology.math.geom.SpiralIterable used on opensource projects

Example 1 with SpiralIterable

use of org.terasology.math.geom.SpiralIterable in project Terasology by MovingBlocks.

the class AbstractSpawner method findSpawnPosition.

/**
 * Tries to find a suitable spawning point based on {@link SurfaceHeightFacet} and {@link SeaLevelFacet}.
 * @param searchRadius the radius within a suitable spawning point will be searched
 * @param world the facet-based world
 * @param pos the desired 2D position in that world
 * @return a 3D position above the surface and sea level or <code>null</code> if none was found
 * @throws IllegalStateException if no SurfaceHeightFacet can be created.
 */
protected Vector3f findSpawnPosition(World world, Vector2i pos, int searchRadius) {
    Vector3i ext = new Vector3i(searchRadius, 1, searchRadius);
    Vector3i desiredPos = new Vector3i(pos.getX(), 1, pos.getY());
    // try and find somewhere in this region a spot to land
    Region3i spawnArea = Region3i.createFromCenterExtents(desiredPos, ext);
    Region worldRegion = world.getWorldData(spawnArea);
    // check if generation uses sea level and surface height facets
    SurfaceHeightFacet surfaceHeightFacet = worldRegion.getFacet(SurfaceHeightFacet.class);
    if (surfaceHeightFacet == null) {
        throw new IllegalStateException("surface height facet not found");
    }
    SeaLevelFacet seaLevelFacet = worldRegion.getFacet(SeaLevelFacet.class);
    int seaLevel = (seaLevelFacet != null) ? seaLevelFacet.getSeaLevel() : 0;
    int spiralRad = searchRadius / 2 - 1;
    SpiralIterable spiral = SpiralIterable.clockwise(pos).maxRadius(spiralRad).scale(2).build();
    for (BaseVector2i test : spiral) {
        float val = surfaceHeightFacet.getWorld(test.getX(), test.getY());
        int height = TeraMath.floorToInt(val);
        if (height >= seaLevel) {
            return new Vector3f(test.getX(), height, test.getY());
        }
    }
    // nothing above sea level found
    float y = surfaceHeightFacet.getWorld(pos.getX(), pos.getY());
    return new Vector3f(pos.getX(), y, pos.getY());
}