OpenGL es2.0 配置自己的matrix

</pre><pre name="code" class="java">package com.gzdxid.utils;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;

import android.opengl.Matrix;

public class MatrixState {

    private static float[] mProjMatrix = new float[16];//4x4矩阵 投影用
    private static float[] mVMatrix = new float[16];//摄像机位置朝向9参数矩阵   
    private static float[] currMatrix;//当前变换矩阵
    public static float[] lightLocation=new float[]{0,0,0};//定位光光源位置
    public static FloatBuffer cameraFB;    
    public static FloatBuffer lightPositionFB;

    //保护变换矩阵的栈
    static float[][] mStack=new float[10][16];
    public static int stackTop=-1;

    public static void setInitStack()//获取不变换初始矩阵
    {
    currMatrix=new float[16];
    Matrix.setRotateM(currMatrix, 0, 0, 1, 0, 0);
    }

    public static void pushMatrix()//保护变换矩阵
    {
    stackTop++;
    for(int i=0;i<16;i++)
    {
    mStack[stackTop][i]=currMatrix[i];
    }
    }

    public static void popMatrix()//恢复变换矩阵
    {
    for(int i=0;i<16;i++)
    {
    currMatrix[i]=mStack[stackTop][i];
    }
    stackTop--;
    }

    public static void translate(float x,float y,float z)//设置沿xyz轴移动
    {
    Matrix.translateM(currMatrix, 0, x, y, z);
    }

    public static void rotate(float angle,float x,float y,float z)//设置绕xyz轴移动
    {
    Matrix.rotateM(currMatrix,0,angle,x,y,z);
    }

    public static void scale(float x,float y,float z)
    {
    Matrix.scaleM(currMatrix,0, x, y, z);
    }

    //插入自带矩阵
    public static void matrix(float[] self)
    {
    float[] result=new float[16];
    Matrix.multiplyMM(result,0,currMatrix,0,self,0);
    currMatrix=result;
    }


    //设置摄像机
    static ByteBuffer llbb= ByteBuffer.allocateDirect(3*4);
    static float[] cameraLocation=new float[3];//摄像机位置
    public static void setCamera
    (
    float cx,//摄像机位置x
    float cy,   //摄像机位置y
    float cz,   //摄像机位置z
    float tx,   //摄像机目标点x
    float ty,   //摄像机目标点y
    float tz,   //摄像机目标点z
    float upx,  //摄像机UP向量X分量
    float upy,  //摄像机UP向量Y分量
    float upz   //摄像机UP向量Z分量
    )
    {
        Matrix.setLookAtM
            (
            mVMatrix, 
            0, 
            cx,
            cy,
            cz,
            tx,
            ty,
            tz,
            upx,
            upy,
            upz
            );

        cameraLocation[0]=cx;
        cameraLocation[1]=cy;
        cameraLocation[2]=cz;

        llbb.clear();
            llbb.order(ByteOrder.nativeOrder());//设置字节顺序
            cameraFB=llbb.asFloatBuffer();
            cameraFB.put(cameraLocation);
            cameraFB.position(0);  
    }

    //设置透视投影参数
    public static void setProjectFrustum
    ( 
    float left,//near面的left
    float right,    //near面的right
    float bottom,   //near面的bottom
    float top,      //near面的top
    float near,//near面距离
    float far       //far面距离
    )
    {
    Matrix.frustumM(mProjMatrix, 0, left, right, bottom, top, near, far);
    }

    //设置正交投影参数
    public static void setProjectOrtho
    (
    float left,//near面的left
    float right,    //near面的right
    float bottom,   //near面的bottom
    float top,      //near面的top
    float near,//near面距离
    float far       //far面距离
    )
    {    
    Matrix.orthoM(mProjMatrix, 0, left, right, bottom, top, near, far);
    }   

    //用于一帧内的摄像机矩阵
    private static float[] mVMatrixForSpecFrame = new float[16];//摄像机位置朝向9参数矩阵   
    public static void copyMVMatrix()
    {
for(int i=0;i<16;i++)
    {
    mVMatrixForSpecFrame[i]=mVMatrix[i];        
    }
    }

    //获取具体物体的总变换矩阵
    static float[] mMVPMatrix=new float[16];
    public static float[] getFinalMatrix()
    {
    Matrix.multiplyMM(mMVPMatrix, 0, mVMatrixForSpecFrame, 0, currMatrix, 0);
        Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mMVPMatrix, 0);        
        return mMVPMatrix;
    }

    //获取具体物体的变换矩阵
    public static float[] getMMatrix()
    {       
        return currMatrix;
    }

    //设置灯光位置的方法
    static ByteBuffer llbbL = ByteBuffer.allocateDirect(3*4);
    public static void setLightLocation(float x,float y,float z)
    {
    llbbL.clear();

    lightLocation[0]=x;
    lightLocation[1]=y;
    lightLocation[2]=z;

        llbbL.order(ByteOrder.nativeOrder());//设置字节顺序
        lightPositionFB=llbbL.asFloatBuffer();
        lightPositionFB.put(lightLocation);
        lightPositionFB.position(0);
    }
}