所谓的滤镜效果就是对图像进行一定的颜色过滤处理，颜色值是32位的int值，ARGB ：A---Alpha值，RGB---颜色值
安卓中对Alpha值的滤镜处理就是利用MaskFilter，其中有两个子类继承MaskFilter
代码语言：javascript
复制 /**
* Create a blur maskfilter.
*
* @param radius 阴影的半径
* @param style NORMOL -- 整个图像都被模糊掉
* SOLID -- 图像边界外产生一层与Paint颜色一致阴影效果，不影响图像的本身
* OUTER -- 图像边界外产生一层阴影，并且将图像变成透明效果
* INNER -- 在图像内部边沿产生模糊效果
* @return The new blur maskfilter
*/
public BlurMaskFilter(float radius, Blur style) {
native_instance = nativeConstructor(radius, style.native_int);
}
代码语言：javascript
复制 @Override
protected void onDraw(Canvas canvas) {
RectF rectF = new RectF(50, 50, 350, 350);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setColor(Color.RED);
canvas.drawRect(rectF, paint);
MaskFilter maskFilter = new BlurMaskFilter(50, BlurMaskFilter.Blur.NORMAL);
paint.setMaskFilter(maskFilter);
canvas.translate(400, 0);
canvas.drawRect(rectF, paint);
maskFilter = new BlurMaskFilter(50, BlurMaskFilter.Blur.SOLID);
paint.setMaskFilter(maskFilter);
canvas.translate(-400, 400);
canvas.drawRect(rectF, paint);
maskFilter = new BlurMaskFilter(50, BlurMaskFilter.Blur.OUTER);
paint.setMaskFilter(maskFilter);
canvas.translate(400, 0);
canvas.drawRect(rectF, paint);
maskFilter = new BlurMaskFilter(50, BlurMaskFilter.Blur.INNER);
paint.setMaskFilter(maskFilter);
canvas.translate(-400, 400);
canvas.drawRect(rectF, paint);
}
下面是普通画矩形，NORMOL ，SOLID ，OUTER ，INNER 分别的效果
- EmbossMaskFilter--用来实现浮雕效果
代码语言：javascript
复制 /**
* Create an emboss maskfilter
*
* @deprecated This subclass is not supported and should not be instantiated.
*
* @param direction 指定光源的位置，长度为xxx的数组标量[x,y,z]
* @param ambient 环境光的因子 （0~1），越接近0，环境光越暗
* @param specular 镜面反射系数 越接近0，镜面反射越强
* @param blurRadius 模糊半径 值越大，模糊效果越明显
* @return the emboss maskfilter
*/
@Deprecated
public EmbossMaskFilter(float[] direction, float ambient, float specular, float blurRadius) {
if (direction.length < 3) {
throw new ArrayIndexOutOfBoundsException();
}
native_instance = nativeConstructor(direction, ambient, specular, blurRadius);
}
代码语言：javascript
复制 @Override
protected void onDraw(Canvas canvas) {
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setColor(Color.RED);
Rect rectf = new Rect(10,10,300,300);
canvas.drawRect(rectf,paint);
canvas.translate(400,0);
//第三个参数发现没什么用
EmbossMaskFilter embossMaskFilter = new EmbossMaskFilter(new float[]{1,1,1},0.2f,1000,50);
paint.setMaskFilter(embossMaskFilter);
canvas.drawRect(rectf,paint);
}
项目地址：https://gitee.com/aruba/Filter.git
