gov.nasa.worldwind.render.PolylineTessellator Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of worldwind-pcm Show documentation

worldwind-pcm

The newest version!

/*
 * Copyright (C) 2014 United States Government as represented by the Administrator of the
 * National Aeronautics and Space Administration.
 * All Rights Reserved.
 */

package gov.nasa.worldwind.render;

import java.nio.IntBuffer;

/**
 * @author dcollins
 * @version $Id: PolylineTessellator.java 2290 2014-08-30 21:27:27Z dcollins $
 */
public class PolylineTessellator
{
    protected IntBuffer indices;
    protected int lastIndex = -1;

    public PolylineTessellator()
    {
        this.indices = IntBuffer.allocate(10);
    }

    public IntBuffer getIndices()
    {
        return this.indices;
    }

    public void reset()
    {
        this.indices.clear();
    }

    public void beginPolyline()
    {
        this.lastIndex = -1;
    }

    public void endPolyline()
    {
        this.lastIndex = -1;
    }

    public void addVertex(double x, double y, double z, int index)
    {
        if (this.lastIndex >= 0)
        {
            this.indices = this.addIndex(this.indices, this.lastIndex);
            this.indices = this.addIndex(this.indices, index);
        }

        this.lastIndex = index;
    }

    protected IntBuffer addIndex(IntBuffer buffer, int index)
    {
        if (!buffer.hasRemaining())
        {
            int newCapacity = buffer.capacity() + buffer.capacity() / 2; // increase capacity by 50%
            IntBuffer newBuffer = IntBuffer.allocate(newCapacity);
            newBuffer.put((IntBuffer) buffer.flip());
            return newBuffer.put(index);
        }
        else
        {
            return buffer.put(index);
        }
    }
}