/**
* 缓冲区工具类
*/
public class BufferUtil {
/**
* 将浮点数组转换成字节缓冲区
*/
public static ByteBuffer arr2ByteBuffer(float[] arr){
ByteBuffer ibb = ByteBuffer.allocateDirect(arr.length * 4);
ibb.order(ByteOrder.nativeOrder());
FloatBuffer fbb = ibb.asFloatBuffer();
fbb.put(arr);
ibb.position(0);
return ibb ;
}
/**
* 将list转换成字节缓冲区
*/
public static ByteBuffer list2ByteBuffer(List<Float> list){
ByteBuffer ibb = ByteBuffer.allocateDirect(list.size() * 4);
ibb.order(ByteOrder.nativeOrder());
FloatBuffer fbb = ibb.asFloatBuffer();
for(Float f : list){
fbb.put(f);
}
ibb.position(0);
return ibb ;
}
}
/**
* 剪裁区
*/
public class MyScissorRenderer extends AbstractMyRenderer{
private int width ;
private int height ;
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
//清平色
gl.glClearColor(0f, 0f, 0f, 1f);
//启用顶点缓冲区数组
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
}
public void onSurfaceChanged(GL10 gl, int width, int height) {
this.width = width ;
this.height = height ;
gl.glViewport(0, 0, width, height);
ratio = (float)width / (float)height;
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
gl.glFrustumf(-ratio, ratio, -1, 1, 3f, 7f);
}
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
gl.glColor4f(1f, 0f, 0f, 1f);
//操作模型视图矩阵
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
//设置眼球的参数
GLU.gluLookAt(gl,0f,0f,5f, 0f, 0f, 0f, 0f,1f,0f);
//启用剪裁
gl.glEnable(GL10.GL_SCISSOR_TEST);
//旋转角度
gl.glRotatef(xrotate, 1, 0, 0);
gl.glRotatef(yrotate, 0, 1, 0);
float[] coords = {
-ratio,1f,2f ,
-ratio,-1f,2f ,
ratio,1f,2f ,
ratio,-1f,2f
};
//颜色数组
float[][] colors = {
{1f,0f,0f,1f},
{0f,1f,0f,1f},
{0f,0f,1f,1f},
{1f,1f,0f,1f},
{0f,1f,1f,1f},
{1f,0f,1f,1f},
};
int step = 20 ;
for(int i = 0 ; i < 6 ; i ++){
//设置剪裁区
gl.glScissor(i * 20, i * 20, width - (i * 20 * 2), height - (i * 20 * 2));
//设置颜色
gl.glColor4f(colors[i][0],colors[i][1],colors[i][2],colors[i][3]);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, BufferUtil.arr2ByteBuffer(coords));
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, 4);
}
}
}
//主界面
public class MainActivity extends Activity {
private AbstractMyRenderer render;
private MyGLSurfaceView view;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
view = new GLSurfaceView(this);
render = new MyTriangleRenderer();
view.setRenderer(render);
//GLSurfaceView.RENDERMODE_CONTINUOUSLY:持续渲染(默认)
//GLSurfaceView.RENDERMODE_WHEN_DIRTY:脏渲染,命令渲染
view.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
setContentView(view);
}
public boolean onKeyDown(int keyCode, KeyEvent event) {
float step = 5f ;
//up
if(keyCode == KeyEvent.KEYCODE_DPAD_UP){
render.xrotate = render.xrotate - step ;
} else if(keyCode == KeyEvent.KEYCODE_DPAD_DOWN){
render.xrotate = render.xrotate + step ;
} else if(keyCode == KeyEvent.KEYCODE_DPAD_LEFT){
render.yrotate = render.yrotate + step ;
} else if(keyCode == KeyEvent.KEYCODE_DPAD_RIGHT){
render.yrotate = render.yrotate - step ;
}
//请求渲染,和脏渲染配合使用
view.requestRender();
return super.onKeyDown(keyCode, event);
}
}