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.content.Context; 22 import android.graphics.*; 23 import android.os.Bundle; 24 import android.view.*; 25 26 public class Vertices extends GraphicsActivity { 27 28 @Override onCreate(Bundle savedInstanceState)29 protected void onCreate(Bundle savedInstanceState) { 30 super.onCreate(savedInstanceState); 31 setContentView(new SampleView(this)); 32 } 33 34 private static class SampleView extends View { 35 private final Paint mPaint = new Paint(); 36 private final float[] mVerts = new float[10]; 37 private final float[] mTexs = new float[10]; 38 private final short[] mIndices = { 0, 1, 2, 3, 4, 1 }; 39 40 private final Matrix mMatrix = new Matrix(); 41 private final Matrix mInverse = new Matrix(); 42 setXY(float[] array, int index, float x, float y)43 private static void setXY(float[] array, int index, float x, float y) { 44 array[index*2 + 0] = x; 45 array[index*2 + 1] = y; 46 } 47 SampleView(Context context)48 public SampleView(Context context) { 49 super(context); 50 setFocusable(true); 51 52 Bitmap bm = BitmapFactory.decodeResource(getResources(), 53 R.drawable.beach); 54 Shader s = new BitmapShader(bm, Shader.TileMode.CLAMP, 55 Shader.TileMode.CLAMP); 56 mPaint.setShader(s); 57 58 float w = bm.getWidth(); 59 float h = bm.getHeight(); 60 // construct our mesh 61 setXY(mTexs, 0, w/2, h/2); 62 setXY(mTexs, 1, 0, 0); 63 setXY(mTexs, 2, w, 0); 64 setXY(mTexs, 3, w, h); 65 setXY(mTexs, 4, 0, h); 66 67 setXY(mVerts, 0, w/2, h/2); 68 setXY(mVerts, 1, 0, 0); 69 setXY(mVerts, 2, w, 0); 70 setXY(mVerts, 3, w, h); 71 setXY(mVerts, 4, 0, h); 72 73 mMatrix.setScale(0.8f, 0.8f); 74 mMatrix.preTranslate(20, 20); 75 mMatrix.invert(mInverse); 76 } 77 onDraw(Canvas canvas)78 @Override protected void onDraw(Canvas canvas) { 79 canvas.drawColor(0xFFCCCCCC); 80 canvas.save(); 81 canvas.concat(mMatrix); 82 83 canvas.drawVertices(Canvas.VertexMode.TRIANGLE_FAN, 10, mVerts, 0, 84 mTexs, 0, null, 0, null, 0, 0, mPaint); 85 86 canvas.translate(0, 240); 87 canvas.drawVertices(Canvas.VertexMode.TRIANGLE_FAN, 10, mVerts, 0, 88 mTexs, 0, null, 0, mIndices, 0, 6, mPaint); 89 90 canvas.restore(); 91 } 92 onTouchEvent(MotionEvent event)93 @Override public boolean onTouchEvent(MotionEvent event) { 94 float[] pt = { event.getX(), event.getY() }; 95 mInverse.mapPoints(pt); 96 setXY(mVerts, 0, pt[0], pt[1]); 97 invalidate(); 98 return true; 99 } 100 101 } 102 } 103 104