glvertex.java

android 例子中的确良ApiDemos。很有代表意义

/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.apis.graphics.kube;

import java.nio.IntBuffer;

public class GLVertex {
	
	public float x;
	public float y;
	public float z;
	final short index;	// index in vertex table
	GLColor color;
	
	GLVertex() {
		this.x = 0;
		this.y = 0;
		this.z = 0;
		this.index = -1;
	}

	GLVertex(float x, float y, float z, int index) {
		this.x = x;
		this.y = y;
		this.z = z;
		this.index = (short)index;
	}

	public boolean equals(Object other) {
		if (other instanceof GLVertex) {
			GLVertex v = (GLVertex)other;
			return (x == v.x && y == v.y && z == v.z);
		}
		return false;
	}

    static public int toFixed(float x) {
    	return (int)(x*65536.0f);
    }

	public void put(IntBuffer vertexBuffer, IntBuffer colorBuffer) {
		vertexBuffer.put(toFixed(x));
		vertexBuffer.put(toFixed(y));
		vertexBuffer.put(toFixed(z));
		if (color == null) {
			colorBuffer.put(0);
			colorBuffer.put(0);
			colorBuffer.put(0);
			colorBuffer.put(0);
		} else {
			colorBuffer.put(color.red);
			colorBuffer.put(color.green);
			colorBuffer.put(color.blue);
			colorBuffer.put(color.alpha);
		}
	}
	
	public void update(IntBuffer vertexBuffer, M4 transform) {
		// skip to location of vertex in mVertex buffer
		vertexBuffer.position(index * 3);
	
		if (transform == null) {
			vertexBuffer.put(toFixed(x));
			vertexBuffer.put(toFixed(y));
			vertexBuffer.put(toFixed(z));			
		} else {
			GLVertex temp = new GLVertex();
			transform.multiply(this, temp);
			vertexBuffer.put(toFixed(temp.x));
			vertexBuffer.put(toFixed(temp.y));
			vertexBuffer.put(toFixed(temp.z));
		}
	}
}