MazeToMesh

package TheMaze.generation;

import com.jme3.math.Vector2f;
import com.jme3.math.Vector3f;
import com.jme3.scene.Mesh;
import com.jme3.scene.VertexBuffer.Type;
import com.jme3.util.BufferUtils;
import java.util.ArrayList;

/**
 * Creates a custom mesh from a matrix of 1 and 0
 * represented through a 2D Array.
 * It automaticly skips invisible Faces.
 * @author Makkuro Na
 */
public class MazeToMesh {

    private ArrayList<Vector3f> vertices;
    private ArrayList<Vector2f> texCoords;
    private ArrayList<Integer> indexes;


    Mesh maze;
    Mesh ground;
    int[][] grid;

    int vPos=0;


    /**
     * Initialites all needed stuff and creates a mesh from the given matrix.
     */
    public MazeToMesh(int[][] M) {

        grid=M;

        maze=new Mesh();
        ground=new Mesh();


        vertices=new ArrayList<Vector3f>();
        texCoords=new ArrayList<Vector2f>();
        indexes=new ArrayList<Integer>();

        build();
        setBuffers();

        buildGround();
    }


    private void build() {

         // Fill the grid.
        for (int x=0;x<grid.length;x++) {
            for (int y=0;y<grid[0].length;y++) {
                if (grid[x][y]==1) {
                    buildBlock(x, y);
                }
            }
        }

    }

    private void buildBlock(int x, int y) {


            vertices.add(new Vector3f(x,4,y));
            vertices.add(new Vector3f(x,0,y));
            vertices.add(new Vector3f(x+1,0,y));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(0,1));
            texCoords.add(new Vector2f(0,0));
            texCoords.add(new Vector2f(1,0));

            vertices.add(new Vector3f(x+1,0,y));
            vertices.add(new Vector3f(x+1,4,y));
            vertices.add(new Vector3f(x,4,y));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(1,0));
            texCoords.add(new Vector2f(1,1));
            texCoords.add(new Vector2f(0,1));



            vertices.add(new Vector3f(x+1,4,y-1));
            vertices.add(new Vector3f(x+1,0,y-1));
            vertices.add(new Vector3f(x,0,y-1));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(0,1));
            texCoords.add(new Vector2f(0,0));
            texCoords.add(new Vector2f(1,0));

            vertices.add(new Vector3f(x,0,y-1));
            vertices.add(new Vector3f(x,4,y-1));
            vertices.add(new Vector3f(x+1,4,y-1));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(1,0));
            texCoords.add(new Vector2f(1,1));
            texCoords.add(new Vector2f(0,1));



            vertices.add(new Vector3f(x,4,y-1));
            vertices.add(new Vector3f(x,0,y-1));
            vertices.add(new Vector3f(x,0,y));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(0,1));
            texCoords.add(new Vector2f(0,0));
            texCoords.add(new Vector2f(1,0));

            vertices.add(new Vector3f(x,0,y));
            vertices.add(new Vector3f(x,4,y));
            vertices.add(new Vector3f(x,4,y-1));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(1,0));
            texCoords.add(new Vector2f(1,1));
            texCoords.add(new Vector2f(0,1));



            vertices.add(new Vector3f(x+1,4,y));
            vertices.add(new Vector3f(x+1,0,y));
            vertices.add(new Vector3f(x+1,0,y-1));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(0,1));
            texCoords.add(new Vector2f(0,0));
            texCoords.add(new Vector2f(1,0));

            vertices.add(new Vector3f(x+1,0,y-1));
            vertices.add(new Vector3f(x+1,4,y-1));
            vertices.add(new Vector3f(x+1,4,y));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(1,0));
            texCoords.add(new Vector2f(1,1));
            texCoords.add(new Vector2f(0,1));


            // And set a top on it... XD
            vertices.add(new Vector3f(x,4,y-1));
            vertices.add(new Vector3f(x,4,y));
            vertices.add(new Vector3f(x+1,4,y));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(0,1));
            texCoords.add(new Vector2f(0,0));
            texCoords.add(new Vector2f(1,0));

            vertices.add(new Vector3f(x+1,4,y));
            vertices.add(new Vector3f(x+1,4,y-1));
            vertices.add(new Vector3f(x,4,y-1));

            indexes.add(vPos);
            indexes.add(vPos+1);
            indexes.add(vPos+2);

            vPos+=3;

            texCoords.add(new Vector2f(1,0));
            texCoords.add(new Vector2f(1,1));
            texCoords.add(new Vector2f(0,1));

    }


    private void setBuffers() {

        // Create the needed arrays from the arraylists
        Vector3f[] V=new Vector3f[vertices.size()];
        for (int i=0;i<vertices.size();i++)
            V[i]=vertices.get(i);

        Vector2f[] T=new Vector2f[texCoords.size()];
        for (int i=0;i<texCoords.size();i++)
            T[i]=texCoords.get(i);

        int[] I=new int[indexes.size()];
        for (int i=0;i<indexes.size();i++)
            I[i]=indexes.get(i);

        maze.setBuffer(Type.Position, 3, BufferUtils.createFloatBuffer(V));
        maze.setBuffer(Type.TexCoord, 2, BufferUtils.createFloatBuffer(T));
        maze.setBuffer(Type.Index,    1, BufferUtils.createIntBuffer(I));
        maze.updateBound();
    }


    public Mesh getMesh() {
        return maze;
    }

    public Mesh getGround() {
        return ground;
    }

    private void buildGround() {
        ArrayList<Vector3f> V=new ArrayList<Vector3f>();
        ArrayList<Vector2f> T=new ArrayList<Vector2f>();
        ArrayList<Integer> I=new ArrayList<Integer>();
        vPos=0;

        for (int x=0;x<grid.length;x++) {
            for (int y=0;y<grid[0].length;y++) {
                if (grid[x][y]==0) {
                    V.add(new Vector3f(x,0,y-1));
                    V.add(new Vector3f(x,0,y));
                    V.add(new Vector3f(x+1,0,y));

                    I.add(vPos);
                    I.add(vPos+1);
                    I.add(vPos+2);

                    vPos+=3;

                    T.add(new Vector2f(0,1));
                    T.add(new Vector2f(0,0));
                    T.add(new Vector2f(1,0));

                    V.add(new Vector3f(x+1,0,y));
                    V.add(new Vector3f(x+1,0,y-1));
                    V.add(new Vector3f(x,0,y-1));

                    I.add(vPos);
                    I.add(vPos+1);
                    I.add(vPos+2);

                    vPos+=3;

                    T.add(new Vector2f(1,0));
                    T.add(new Vector2f(1,1));
                    T.add(new Vector2f(0,1));
                }
            }
        }


        // Create the needed arrays from the arraylists
        Vector3f[] V2=new Vector3f[V.size()];
        for (int i=0;i<V.size();i++)
            V2[i]=V.get(i);

        Vector2f[] T2=new Vector2f[T.size()];
        for (int i=0;i<T.size();i++)
            T2[i]=T.get(i);

        int[] I2=new int[I.size()];
        for (int i=0;i<I.size();i++)
            I2[i]=I.get(i);

        ground.setBuffer(Type.Position, 3, BufferUtils.createFloatBuffer(V2));
        ground.setBuffer(Type.TexCoord, 2, BufferUtils.createFloatBuffer(T2));
        ground.setBuffer(Type.Index,    1, BufferUtils.createIntBuffer(I2));
        ground.updateBound();


    }

}