android中抗锯齿

2023-11-04 23:48

文章标签 android 抗锯齿

本文主要是介绍android中抗锯齿，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

出现锯齿条件：倾斜或旋转、快速变化。

当在屏幕上画一条直线时, 横竖不会出现锯齿, 但是当斜着画时, 就会出现锯齿的效果。

画笔的抗锯齿（用于线条等）设置：

paint.setAntiAlias(true);

图片线条（通用）的抗锯齿需要另外设置：

canvas.setDrawFilter(new PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG));

实例代码（说明见注释）：

package com.example.antialiasdemon;import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.PaintFlagsDrawFilter;
import android.view.View;public class GameView extends View {private Paint paint;private Bitmap bitmap;private Matrix matrix; // 用来旋转图片public GameView(Context context) {super(context);paint = new Paint();paint.setColor(Color.RED);bitmap = BitmapFactory.decodeResource(this.getResources(),R.drawable.ic_launcher);matrix = new Matrix();this.setFocusable(true);}protected void onDraw(Canvas canvas) {super.onDraw(canvas);// 1. 画一条线, 倾斜后会锯齿canvas.drawLine(0, 0, 100, 200, paint);// 2. 还是上面那条线,设置抗锯齿后的效果paint.setAntiAlias(true);// 设置线条等图形的抗锯齿canvas.drawLine(20, 0, 120, 200, paint);// 1、画一个图片. (绘制图片时可以不要最后一个参数---画笔)canvas.drawBitmap(bitmap, 0, 100, null);// 2、旋转倾斜后, 就会出现锯齿效果matrix.setRotate(75);// 旋转75度matrix.postTranslate(300, 300);// 移动100\100.(第一个用set, 后面的设置都用post才叠加)canvas.drawBitmap(bitmap, matrix, null);// 3、旋转后, 图片的抗锯齿。canvas.setDrawFilter(new PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG| Paint.FILTER_BITMAP_FLAG)); // 设置图形、图片的抗锯齿。可用于线条等。按位或.matrix.postTranslate(266, 0);canvas.drawBitmap(bitmap, matrix, null);}}

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.PaintFlagsDrawFilter;
import android.view.View;
/*** 抗锯齿* @author neng**/
@SuppressLint("DrawAllocation")
public class GameView extends View
{private Paint paint;private Bitmap bitmap;private Matrix matrix; //用来旋转图片public GameView(Context context){super(context);paint = new Paint();paint.setColor(Color.RED);bitmap = BitmapFactory.decodeResource(this.getResources(),R.drawable.ic_launcher);matrix = new Matrix();this.setFocusable(true);}@Overrideprotected void onDraw(Canvas canvas){super.onDraw(canvas);//1. 画一条线, 倾斜后会锯齿canvas.drawLine(0, 0, 100, 200, paint);//2. 还是上面那条线,设置抗锯齿后的效果paint.setAntiAlias(true);//设置线条等图形的抗锯齿canvas.drawLine(20, 0, 120, 200, paint);//1、画一个图片. (绘制图片时可以不要最后一个参数---画笔)canvas.drawBitmap(bitmap, 0, 100, null);//2、旋转倾斜后, 就会出现锯齿效果matrix.setRotate(75);//旋转75度matrix.postTranslate(100, 100);//移动100\100.(第一个用set, 后面的设置都用post才叠加)canvas.drawBitmap(bitmap, matrix, null);//3、旋转后, 图片的抗锯齿。canvas.setDrawFilter(new PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG| Paint.FILTER_BITMAP_FLAG)); //设置图形、图片的抗锯齿。可用于线条等。按位或.matrix.postTranslate(66, 0);canvas.drawBitmap(bitmap, matrix, null);}
}