Quad.java

package com.javamarcher.geometry;

import com.javamarcher.ecs.component.Transform;

public class Quad {
	private Transform transform = new Transform();
	
	private final VertexData[] vertices;
	
	// OpenGL expects to draw vertices in counter clockwise order by default
	private final byte[] indices = {
	        0, 1, 2,		// Left bottom triangle
	        2, 3, 0			// Right top triangle
	};
	
	public Quad() {
		vertices = setupVertexData();
	}
	
	private VertexData[] setupVertexData() {
		// The z-coordinate of the vertex positions is used as an index for the frustum rays
		final VertexData v1 = new VertexData();		// Top Left
		v1.setPosition(-1f, 1f, 0f);
		v1.setColor(1f, 0f, 0f);
		v1.setUV(0f, 0f);
		final VertexData v2 = new VertexData();		// Bottom Left
		v2.setPosition(-1f, -1f, 3f);
		v2.setColor(0f, 1f, 0f);
		v2.setUV(0f, 1f);
		final VertexData v3 = new VertexData();		// Bottom Right
		v3.setPosition(1f, -1f, 2f);
		v3.setColor(0f, 0f, 1f);
		v1.setUV(1f, 1f);
		final VertexData v4 = new VertexData();		// Top Right
		v4.setPosition(1f, 1f, 1f);
		v4.setColor(1f, 1f, 1f);
		v1.setUV(1f, 0f);
		
		return new VertexData[] {v1, v2, v3, v4};
	}

	public Transform getTransform() {
		return transform;
	}

	public VertexData[] getVertices() {
		return vertices;
	}

	public byte[] getIndices() {
		return indices;
	}
}