Android 颜色渲染(十) ComposeShader组合渲染

Android 颜色渲染(十) ComposeShader组合渲染

分类： Android Android 颜色渲染 2013-09-03 20:13  1186人阅读  评论(0)  收藏  举报

目录(?)[+]

Android 颜色处理(十) ComposeShader组合渲染

  

 

public ComposeShader(Shader shaderA,Shader shaderB, Xfermode mode)

Parameters

shaderA	渲染器A,Shader及其子类对象
shaderB	渲染器B,Shader及其子类对象
mode	两种渲染器组合的模式,Xfermode对象

public ComposeShader(Shader shaderA,Shader shaderB, PorterDuff.Mode mode)

Parameters

shaderA	渲染器A,Shader及其子类对象
shaderB	渲染器B,Shader及其子类对象
mode	.两种渲染器组合的模式,ProterDuff.Mode对象

Xfermode及ProterBuff.Mode具体含义见上一篇: 

Android 颜色渲染(八) PorterDuff及Xfermode详解

  ComposeShader,和AnimationSet的用法相似.是可以将两种颜色渲染器的效果进行组合:

                                             

以上图像由BimtmapShader和LinearGradient两种效果组合绘制,其中位图渲染 平铺模式使用的为镜像模式,  组合渲染使用了ProterDuff叠加模式,具体见如下代码:

MainActivity:

 package com.tony.testshader;

 import android.os.Bundle;
 import android.app.Activity;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.view.Menu;
 import android.widget.SeekBar;
 import android.widget.SeekBar.OnSeekBarChangeListener;

 public class MainActivity extends Activity  implements OnSeekBarChangeListener{

     private SweepGradientView sweepGradientView;
     private ComposeShaderView composeShaderView;

      private SeekBar seekbar;
      private PorterDuffView porterDuffView;
      private int currentId;
      private WaterRipplesView waterRipplesView;



     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

         composeShaderView = new ComposeShaderView(this);
         setContentView(composeShaderView);

     }

     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.main, menu);
         return true;
     }


 }

ComposeShaderView:

 package com.tony.testshader;

 import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.BitmapShader;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.ComposeShader;
 import android.graphics.LinearGradient;
 import android.graphics.Paint;
 import android.graphics.PorterDuff;
 import android.graphics.Shader;
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.ShapeDrawable;
 import android.util.AttributeSet;
 import android.view.View;

 public class ComposeShaderView extends View {

     Bitmap mBitmap = null;
     int bitwidth = 0;
     int bitheight = 0;
     Paint mPaint = null;
     // bitmap渲染
     Shader mBitmapShader = null;
     // 线性渐变渲染
     Shader mLinearGradient = null;
     // 混合渲染
     Shader mComposeShader = null;

     ShapeDrawable mShapeDrawable = null;

     public ComposeShaderView(Context context) {
         super(context);
         // 装载资源
         mBitmap = ((BitmapDrawable) getResources().getDrawable(R.drawable.list_top))
                 .getBitmap();
         // 得到宽高
         bitwidth = mBitmap.getWidth();
         bitheight = mBitmap.getHeight();
         // 创建BitmapShader对象
         mBitmapShader = new BitmapShader(mBitmap, Shader.TileMode.MIRROR,
                 Shader.TileMode.MIRROR);
         // 创建LinearGradient并设置渐变颜色数组,平铺效果为镜像
         mLinearGradient = new LinearGradient(0, 0, 0, 100, new int[] {
                 Color.WHITE, Color.LTGRAY, Color.TRANSPARENT, Color.GREEN }, null,
                 Shader.TileMode.MIRROR);

         // 混合渲染 将两个效果叠加,使用PorterDuff叠加模式
         mComposeShader = new ComposeShader(mBitmapShader, mLinearGradient,  PorterDuff.Mode.MULTIPLY);
         mPaint = new Paint();
     }

     public ComposeShaderView(Context context, AttributeSet attrs) {
         super(context, attrs);
     }

     @Override
     protected void onDraw(Canvas canvas) {
         super.onDraw(canvas);

            // 绘制混合渲染效果
         mPaint.setShader(mComposeShader);
         canvas.drawCircle(240, 360, 200, mPaint);

     }

 }