1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.example.android.apis.graphics; 18 19 import com.example.android.apis.R; 20 21 import android.app.Activity; 22 import android.content.Context; 23 import android.graphics.*; 24 import android.graphics.drawable.*; 25 import android.os.Bundle; 26 import android.view.KeyEvent; 27 import android.view.*; 28 29 import java.io.IOException; 30 import java.io.InputStream; 31 32 public class Vertices extends GraphicsActivity { 33 34 @Override onCreate(Bundle savedInstanceState)35 protected void onCreate(Bundle savedInstanceState) { 36 super.onCreate(savedInstanceState); 37 setContentView(new SampleView(this)); 38 } 39 40 private static class SampleView extends View { 41 private final Paint mPaint = new Paint(); 42 private final float[] mVerts = new float[10]; 43 private final float[] mTexs = new float[10]; 44 private final int[] mColors = new int[10]; 45 private final short[] mIndices = { 0, 1, 2, 3, 4, 1 }; 46 47 private final Matrix mMatrix = new Matrix(); 48 private final Matrix mInverse = new Matrix(); 49 setXY(float[] array, int index, float x, float y)50 private static void setXY(float[] array, int index, float x, float y) { 51 array[index*2 + 0] = x; 52 array[index*2 + 1] = y; 53 } 54 SampleView(Context context)55 public SampleView(Context context) { 56 super(context); 57 setFocusable(true); 58 59 Bitmap bm = BitmapFactory.decodeResource(getResources(), 60 R.drawable.beach); 61 Shader s = new BitmapShader(bm, Shader.TileMode.CLAMP, 62 Shader.TileMode.CLAMP); 63 mPaint.setShader(s); 64 65 float w = bm.getWidth(); 66 float h = bm.getHeight(); 67 // construct our mesh 68 setXY(mTexs, 0, w/2, h/2); 69 setXY(mTexs, 1, 0, 0); 70 setXY(mTexs, 2, w, 0); 71 setXY(mTexs, 3, w, h); 72 setXY(mTexs, 4, 0, h); 73 74 setXY(mVerts, 0, w/2, h/2); 75 setXY(mVerts, 1, 0, 0); 76 setXY(mVerts, 2, w, 0); 77 setXY(mVerts, 3, w, h); 78 setXY(mVerts, 4, 0, h); 79 80 mMatrix.setScale(0.8f, 0.8f); 81 mMatrix.preTranslate(20, 20); 82 mMatrix.invert(mInverse); 83 } 84 onDraw(Canvas canvas)85 @Override protected void onDraw(Canvas canvas) { 86 canvas.drawColor(0xFFCCCCCC); 87 canvas.save(); 88 canvas.concat(mMatrix); 89 90 canvas.drawVertices(Canvas.VertexMode.TRIANGLE_FAN, 10, mVerts, 0, 91 mTexs, 0, null, 0, null, 0, 0, mPaint); 92 93 canvas.translate(0, 240); 94 canvas.drawVertices(Canvas.VertexMode.TRIANGLE_FAN, 10, mVerts, 0, 95 mTexs, 0, null, 0, mIndices, 0, 6, mPaint); 96 97 canvas.restore(); 98 } 99 onTouchEvent(MotionEvent event)100 @Override public boolean onTouchEvent(MotionEvent event) { 101 float[] pt = { event.getX(), event.getY() }; 102 mInverse.mapPoints(pt); 103 setXY(mVerts, 0, pt[0], pt[1]); 104 invalidate(); 105 return true; 106 } 107 108 } 109 } 110 111