openels20 三角形

来源：互联网发布：电脑监控软件价格编辑：程序博客网时间：2024/06/05 10:06
package edu.wuwang.opengl.jason.demo1;import android.opengl.GLES20;import android.opengl.GLSurfaceView;import java.nio.ByteBuffer;import java.nio.ByteOrder;import java.nio.FloatBuffer;import javax.microedition.khronos.egl.EGLConfig;import javax.microedition.khronos.opengles.GL10;/** * Created by Administrator on 2017/9/25. */public class MyRender implements GLSurfaceView.Renderer {    private int mProgram;    static final int COORDS_PER_VERTEX = 3;    static float triangleCoords[] = {            0.5f,  0.5f, 0.0f, // top            -0.5f, -0.5f, 0.0f, // bottom left            0.5f, -0.5f, 0.0f  // bottom right    };    private final String vertexShaderCode =            "attribute vec4 vPosition;" +                    "void main() {" +                    "  gl_Position = vPosition;" +                    "}";    private final String fragmentShaderCode =            "precision mediump float;" +                    "uniform vec4 vColor;" +                    "void main() {" +                    "  gl_FragColor = vColor;" +                    "}";    private int mPositionHandle;    private int mColorHandle;    private float[] mViewMatrix=new float[16];    //顶点个数    private final int vertexCount = triangleCoords.length / COORDS_PER_VERTEX;    //顶点之间的偏移量    private final int vertexStride = COORDS_PER_VERTEX * 4; // 每个顶点四个字节    private int mMatrixHandler;    private FloatBuffer vertexBuffer;    //设置颜色，依次为红绿蓝和透明通道    float color[] = { 1.0f, 0.6f, 0.5f, 1.0f };    public MyRender() {    }    @Override    public void onSurfaceCreated(GL10 gl, EGLConfig config) {        GLES20.glClearColor(0.5f,0.5f,0.5f,1.0f);        ByteBuffer bb = ByteBuffer.allocateDirect(                triangleCoords.length * 4);        bb.order(ByteOrder.nativeOrder());        vertexBuffer = bb.asFloatBuffer();        vertexBuffer.put(triangleCoords);        vertexBuffer.position(0);        int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER,                vertexShaderCode);        int fragmentShader = loadShader(GLES20.GL_FRAGMENT_SHADER,                fragmentShaderCode);        //创建一个空的OpenGLES程序        mProgram = GLES20.glCreateProgram();        //将顶点着色器加入到程序        GLES20.glAttachShader(mProgram, vertexShader);        //将片元着色器加入到程序中        GLES20.glAttachShader(mProgram, fragmentShader);        //连接到着色器程序        GLES20.glLinkProgram(mProgram);    }    @Override    public void onSurfaceChanged(GL10 gl, int width, int height) {        GLES20.glViewport(0,0,width,height);    }    @Override    public void onDrawFrame(GL10 gl) {        GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT|GLES20.GL_DEPTH_BUFFER_BIT);        GLES20.glUseProgram(mProgram);        //获取顶点着色器的vPosition成员句柄        mPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");        //启用三角形顶点的句柄        GLES20.glEnableVertexAttribArray(mPositionHandle);        //准备三角形的坐标数据        GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX,                GLES20.GL_FLOAT, false,                vertexStride, vertexBuffer);        //获取片元着色器的vColor成员的句柄        mColorHandle = GLES20.glGetUniformLocation(mProgram, "vColor");        //设置绘制三角形的颜色        GLES20.glUniform4fv(mColorHandle, 1, color, 0);        //绘制三角形        GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, vertexCount);        //禁止顶点数组的句柄        GLES20.glDisableVertexAttribArray(mPositionHandle);    }    public int loadShader(int type, String shaderCode){        //根据type创建顶点着色器或者片元着色器        int shader = GLES20.glCreateShader(type);        //将资源加入到着色器中，并编译        GLES20.glShaderSource(shader, shaderCode);        GLES20.glCompileShader(shader);        return shader;    }}
阅读全文
0 0