WallSignModel.java

/* Copyright (c) 2012 Jesper Öqvist <jesper@llbit.se>
 *
 * This file is part of Chunky.
 *
 * Chunky is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Chunky is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with Chunky.  If not, see <http://www.gnu.org/licenses/>.
 */
package se.llbit.chunky.model;

import se.llbit.chunky.resources.Texture;
import se.llbit.math.Quad;
import se.llbit.math.Ray;
import se.llbit.math.Vector3;
import se.llbit.math.Vector4;

public class WallSignModel {

  // Distance the sign is offset from the wall (mimicking Minecraft).
  private static final double offset = 0.02;

  private static Quad[][] faces = {{}, {},

      // facing north
      {
          // north
          new Quad(new Vector3(1, .2, .875 + offset), new Vector3(0, .2, .875 + offset),
              new Vector3(1, .8, .875 + offset), new Vector4(1, 0, .2, .8)),

          // south
          new Quad(new Vector3(0, .2, 1 - offset), new Vector3(1, .2, 1 - offset),
              new Vector3(0, .8, 1 - offset), new Vector4(0, 1, .2, .8)),

          // west
          new Quad(new Vector3(0, .2, .875 + offset), new Vector3(0, .2, 1 - offset),
              new Vector3(0, .8, .875 + offset), new Vector4(.875 + offset, 1 - offset, .2, .8)),

          // east
          new Quad(new Vector3(1, .2, 1 - offset), new Vector3(1, .2, .875 + offset),
              new Vector3(1, .8, 1 - offset), new Vector4(1 - offset, .875 + offset, .2, .8)),

          // top
          new Quad(new Vector3(1, .8, .875 + offset), new Vector3(0, .8, .875 + offset),
              new Vector3(1, .8, 1 - offset), new Vector4(1, 0, .875 + offset, 1 - offset)),

          // bottom
          new Quad(new Vector3(0, .2, .875 + offset), new Vector3(1, .2, .875 + offset),
              new Vector3(0, .2, 1 - offset), new Vector4(0, 1, .875 + offset, 1 - offset)),},

      // facing south
      {},

      // facing west
      {},

      // facing east
      {},};

  static {
    faces[5] = Model.rotateY(faces[2]);
    faces[3] = Model.rotateY(faces[5]);
    faces[4] = Model.rotateY(faces[3]);
  }

  public static boolean intersect(Ray ray) {
    boolean hit = false;
    ray.t = Double.POSITIVE_INFINITY;
    for (Quad face : faces[ray.getBlockData() % 6]) {
      if (face.intersect(ray)) {
        Texture.oakPlanks.getColor(ray);
        ray.n.set(face.n);
        ray.t = ray.tNext;
        hit = true;
      }
    }
    if (hit) {
      ray.color.w = 1;
      ray.distance += ray.t;
      ray.o.scaleAdd(ray.t, ray.d);
    }
    return hit;
  }
}