Android-UI-图形绘制-Paint

图形绘制---paint  

渲染：

以位图渲染为例：

BitmapShader.java  

public class MyGradientView extends View {

    private Paint mPaint;
    private Bitmap mBitMap = null;

    private int mWidth;
    private int mHeight;
    private int[] mColors = {Color.RED, Color.GREEN, Color.BLUE, Color.YELLOW};

    public MyGradientView(Context context) {
        super(context);
        mBitMap = ((BitmapDrawable) getResources().getDrawable(R.drawable.xyjy2)).getBitmap();
        mPaint = new Paint();
        mWidth = mBitMap.getWidth();
        mHeight = mBitMap.getHeight();
    }

    public MyGradientView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        mBitMap = ((BitmapDrawable) getResources().getDrawable(R.drawable.xyjy2)).getBitmap();
        mPaint = new Paint();
        mWidth = mBitMap.getWidth();
        mHeight = mBitMap.getHeight();
    }

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

        /**
         * 位图渲染，BitmapShader(@NonNull Bitmap bitmap, @NonNull TileMode tileX, @NonNull TileMode tileY)
         * Bitmap:构造shader使用的bitmap
         * tileX：X轴方向的TileMode
         * tileY:Y轴方向的TileMode
         */

        BitmapShader bitMapShader = new BitmapShader(mBitMap, Shader.TileMode.REPEAT,
                Shader.TileMode.REPEAT);
        mPaint.setShader(bitMapShader);
        mPaint.setAntiAlias(true);

        canvas.drawRect(new Rect(0, 0, 1000, 1600), mPaint);
    }

}

滤镜：

FilterView.java  （使用颜色矩阵实现底片效果、颜色增强、黑白照片、复古等效果）

package com.dn_alan.myapplication.filter;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.BlurMaskFilter;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.EmbossMaskFilter;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffColorFilter;
import android.graphics.RectF;
import android.view.MotionEvent;
import android.view.View;

import com.dn_alan.myapplication.R;


public class FilterView extends View {

    Paint paint;

    Bitmap bitmap;

    public FilterView(Context context) {
        super(context);
        init();
    }

    private void init() {

        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        paint.setColor(Color.RED);

        bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.xyjy2);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        //关闭单个View的硬件加速功
//      setLayerType(View.LAYER_TYPE_SOFTWARE,null);
//
        RectF rectF = new RectF(200,100,bitmap.getWidth()+200,bitmap.getHeight());
        paint.reset();

        canvas.drawBitmap(bitmap,null, rectF,paint);

        // 平移运算---加法
//        ColorMatrix colorMartrix = new ColorMatrix(new float[]{
//                1, 0,0,0,0,
//                0,1,0,0,100,
//                0,0,1,0,0,
//                0,0,0,1,0,
//        });

        // 反相效果 -- 底片效果
//       ColorMatrix colorMartrix = new ColorMatrix(new float[]{
//                -1, 0,0,0,255,
//                0,-1,0,0,255,
//                0,0,-1,0,255,
//                0,0,0,1,0,
//        });

        // 缩放运算---乘法 -- 颜色增强
//        ColorMatrix colorMartrix = new ColorMatrix(new float[]{
//                1.2f, 0,0,0,0,
//                0,1.2f,0,0,0,
//                0,0,1.2f,0,0,
//                0,0,0,1.2f,0,
//        });

         /** 黑白照片
          *是将我们的三通道变为单通道的灰度模式
          *去色原理：只要把R G B 三通道的色彩信息设置成一样，那么图像就会变成灰色，
          *同时为了保证图像亮度不变，同一个通道里的R+G+B =1
          */
//        ColorMatrix colorMartrix = new ColorMatrix(new float[]{
//                0.213f, 0.715f,0.072f,0,0,
//                0.213f, 0.715f,0.072f,0,0,
//                0.213f, 0.715f,0.072f,0,0,
//                0,0,0,1,0,
//        });


        // 发色效果---（比如红色和绿色交换）
//        ColorMatrix colorMartrix = new ColorMatrix(new float[]{
//                1,0,0,0,0,
//                0, 0,1,0,0,
//                0,1,0,0,0,
//                0,0,0,0.5F,0,
//        });

        // 复古效果
//        ColorMatrix colorMartrix = new ColorMatrix(new float[]{
//                1/2f,1/2f,1/2f,0,0,
//                1/3f, 1/3f,1/3f,0,0,
//                1/4f,1/4f,1/4f,0,0,
//                0,0,0,1,0,
//        });

        // 颜色通道过滤
        //两个矩阵
        //本身颜色矩阵 A
        //过滤矩阵  c
        //a*c=out color
        ColorMatrix colorMartrix = new ColorMatrix(new float[]{
                1.3F,0,0,0,0,
                0,1.3F,0,0,0,
                0,0,1.3F,0,0,
                0,0,0,1,0,
        });

        RectF rectF2 = new RectF(200,100 + bitmap.getHeight(),bitmap.getWidth()+200,bitmap.getHeight() * 2);
        paint.setColorFilter(new ColorMatrixColorFilter(colorMartrix));
        canvas.drawBitmap(bitmap,null, rectF2,paint);
    }


}

Xfermode：

PorterDuff所有模式：https://developer.android.google.cn/reference/android/graphics/PorterDuff.Mode?hl=en#ADD

 

本文地址：https://blog.csdn.net/qq_23956889/article/details/112341410