官方Xfermode的实例 里面18中模式详解
public class XfermodesActivity extends AppCompatActivity {
// create a bitmap with a circle, used for the "dst" image
static Bitmap makeDst(int w, int h) {
Bitmap bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(bm);
Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
p.setColor(0xFFFFCC44);
c.drawOval(new RectF(0, 0, w * 3 / 4, h * 3 / 4), p);
return bm;
}
// create a bitmap with a rect, used for the "src" image
static Bitmap makeSrc(int w, int h) {
Bitmap bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(bm);
Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
p.setColor(0xFF66AAFF);
c.drawRect(w / 3, h / 3, w * 19 / 20, h * 19 / 20, p);
return bm;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(new SampleView(this));
}
private static class SampleView extends View {
private static final int W = 320;
private static final int H = W;
private static final int ROW_MAX = 4; // number of samples per row
private Bitmap mSrcB;
private Bitmap mDstB;
private Shader mBG; // background checker-board pattern
private Paint mPaint;
//效果作用于src源图像区域
private static final Xfermode[] sModes = {
//所绘制不会提交到画布上
new PorterDuffXfermode(PorterDuff.Mode.CLEAR),
//显示上层绘制的图像
new PorterDuffXfermode(PorterDuff.Mode.SRC),
//显示下层绘制图像
new PorterDuffXfermode(PorterDuff.Mode.DST),
//正常绘制显示,上下层绘制叠盖
new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER),
//上下层都显示,下层居上显示
new PorterDuffXfermode(PorterDuff.Mode.DST_OVER),
//取两层绘制交集,显示上层
new PorterDuffXfermode(PorterDuff.Mode.SRC_IN),
//取两层绘制交集,显示下层
new PorterDuffXfermode(PorterDuff.Mode.DST_IN),
//取上层绘制非交集部分,交集部分变成透明
new PorterDuffXfermode(PorterDuff.Mode.SRC_OUT),
//取下层绘制非交集部分,交集部分变成透明
new PorterDuffXfermode(PorterDuff.Mode.DST_OUT),
//取上层交集部分与下层非交集部分
new PorterDuffXfermode(PorterDuff.Mode.SRC_ATOP),
//取下层交集部分与上层非交集部分
new PorterDuffXfermode(PorterDuff.Mode.DST_ATOP),
//去除两图层交集部分
new PorterDuffXfermode(PorterDuff.Mode.XOR),
//取两图层全部区域,交集部分颜色加深
new PorterDuffXfermode(PorterDuff.Mode.DARKEN),
//取两图层全部区域,交集部分颜色点亮
new PorterDuffXfermode(PorterDuff.Mode.LIGHTEN),
//取两图层交集部分,颜色叠加
new PorterDuffXfermode(PorterDuff.Mode.MULTIPLY),
//取两图层全部区域,交集部分滤色
new PorterDuffXfermode(PorterDuff.Mode.SCREEN),
//取两图层全部区域,交集部分饱和度相加
new PorterDuffXfermode(PorterDuff.Mode.ADD),
//取两图层全部区域,交集部分叠加
new PorterDuffXfermode(PorterDuff.Mode.OVERLAY)
};
private static final String[] sLabels = {
"Clear", "Src", "Dst", "SrcOver",
"DstOver", "SrcIn", "DstIn", "SrcOut",
"DstOut", "SrcATop", "DstATop", "Xor",
"Darken", "Lighten", "Multiply", "Screen", "Add","Overlay"
};
public SampleView(Context context) {
super(context);
mSrcB = makeSrc(W, H);
mDstB = makeDst(W, H);
// make a ckeckerboard pattern
Bitmap bm = Bitmap.createBitmap(new int[]{0xFFFFFFFF, 0xFFCCCCCC, 0xFFCCCCCC, 0xFFFFFFFF}, 2, 2,
Bitmap.Config.RGB_565);
mBG = new BitmapShader(bm,
Shader.TileMode.REPEAT,
Shader.TileMode.REPEAT);
Matrix m = new Matrix();
m.setScale(6, 6);
mBG.setLocalMatrix(m);
mPaint = new Paint();
mPaint.setStrokeWidth(2);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setColor(Color.GRAY);
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.WHITE);
Paint labelP = new Paint(Paint.ANTI_ALIAS_FLAG);
labelP.setTextAlign(Paint.Align.CENTER);
Paint paint = new Paint();
paint.setFilterBitmap(false);
canvas.translate(15, 15);
canvas.drawBitmap(mDstB, 0, 0, paint);
canvas.drawRect(0,0, mDstB.getWidth(), mDstB.getHeight(), mPaint);
canvas.drawBitmap(mSrcB, mDstB.getWidth() + 15, 0, paint);
canvas.drawRect(mDstB.getWidth() + 15,0, mDstB.getWidth() + 15 + mSrcB.getWidth(), mSrcB.getHeight(), mPaint);
canvas.translate(0, mDstB.getHeight() + 15);
int x = 0;
int y = 0;
for (int i = 0; i < sModes.length; i++) {
// draw the border
paint.setStyle(Paint.Style.STROKE);
paint.setShader(null);
canvas.drawRect(x - 0.5f, y - 0.5f,
x + W + 0.5f, y + H + 0.5f, paint);
// draw the checker-board pattern
paint.setStyle(Paint.Style.FILL);
paint.setShader(mBG);
canvas.drawRect(x, y, x + W, y + H, paint);
// draw the src/dst example into our offscreen bitmap
int sc = canvas.saveLayer(x, y, x + W, y + H, null, Canvas.ALL_SAVE_FLAG);
canvas.translate(x, y);
//目标图像
canvas.drawBitmap(mDstB, 0, 0, paint);
paint.setXfermode(sModes[i]);
//源图像
canvas.drawBitmap(mSrcB, 0, 0, paint);
paint.setXfermode(null);
canvas.restoreToCount(sc);
// draw the label
canvas.drawText(sLabels[i], x + W / 2, y - labelP.getTextSize() / 2, labelP);
x += W + 10;
// wrap around when we've drawn enough for one row
if ((i % ROW_MAX) == ROW_MAX - 1) {
x = 0;
y += H + 30;
}
}
}
}
}
谷歌官方实例去掉透明区域重新混合
public class XfermodesView extends View {
private static int W = 250;
private static int H = 250;
private static final int ROW_MAX = 4; // number of samples per row
private Bitmap mSrcB;
private Bitmap mDstB;
private Shader mBG; // background checker-board pattern
//其中Sa全称为Source alpha表示源图的Alpha通道;Sc全称为Source color表示源图的颜色;Da全称为Destination alpha表示目标图的Alpha通道;Dc全称为Destination color表示目标图的颜色,[...,..]前半部分计算的是结果图像的Alpha通道值,“,”后半部分计算的是结果图像的颜色值。
//效果作用于src源图像区域
private static final Xfermode[] sModes = {
//所绘制不会提交到画布上
new PorterDuffXfermode(PorterDuff.Mode.CLEAR),
//显示上层绘制的图像
new PorterDuffXfermode(PorterDuff.Mode.SRC),
//显示下层绘制图像
new PorterDuffXfermode(PorterDuff.Mode.DST),
//正常绘制显示,上下层绘制叠盖
new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER),
//上下层都显示,下层居上显示
new PorterDuffXfermode(PorterDuff.Mode.DST_OVER),
//取两层绘制交集,显示上层
new PorterDuffXfermode(PorterDuff.Mode.SRC_IN),
//取两层绘制交集,显示下层
new PorterDuffXfermode(PorterDuff.Mode.DST_IN),
//取上层绘制非交集部分,交集部分变成透明
new PorterDuffXfermode(PorterDuff.Mode.SRC_OUT),
//取下层绘制非交集部分,交集部分变成透明
new PorterDuffXfermode(PorterDuff.Mode.DST_OUT),
//取上层交集部分与下层非交集部分
new PorterDuffXfermode(PorterDuff.Mode.SRC_ATOP),
//取下层交集部分与上层非交集部分
new PorterDuffXfermode(PorterDuff.Mode.DST_ATOP),
//去除两图层交集部分
new PorterDuffXfermode(PorterDuff.Mode.XOR),
//取两图层全部区域,交集部分颜色加深
new PorterDuffXfermode(PorterDuff.Mode.DARKEN),
//取两图层全部区域,交集部分颜色点亮
new PorterDuffXfermode(PorterDuff.Mode.LIGHTEN),
//取两图层交集部分,颜色叠加
new PorterDuffXfermode(PorterDuff.Mode.MULTIPLY),
//取两图层全部区域,交集部分滤色
new PorterDuffXfermode(PorterDuff.Mode.SCREEN),
//取两图层全部区域,交集部分饱和度相加
new PorterDuffXfermode(PorterDuff.Mode.ADD),
//取两图层全部区域,交集部分叠加
new PorterDuffXfermode(PorterDuff.Mode.OVERLAY)
};
private static final String[] sLabels = {
"Clear", "Src", "Dst", "SrcOver",
"DstOver", "SrcIn", "DstIn", "SrcOut",
"DstOut", "SrcATop", "DstATop", "Xor",
"Darken", "Lighten", "Multiply", "Screen", "Add","Overlay"
};
public XfermodesView(Context context) {
this(context, null);
}
public XfermodesView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public XfermodesView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
WindowManager windowManager = (WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE);
if (windowManager != null) {
DisplayMetrics display = new DisplayMetrics();
windowManager.getDefaultDisplay().getMetrics(display);
W = H = (display.widthPixels - 64) / ROW_MAX; //得到矩形
}
//1,API 14之后,有些函数不支持硬件加速,需要禁用
setLayerType(View.LAYER_TYPE_SOFTWARE, null);
mSrcB = makeSrc(W, H);
mDstB = makeDst(W, H);
//根据width和height创建空位图,然后用指定的颜色数组colors来从左到右从上至下一次填充颜色
//make a ckeckerboard pattern
Bitmap bm = Bitmap.createBitmap(new int[]{0xFFFFFFFF, 0xFFCCCCCC, 0xFFCCCCCC, 0xFFFFFFFF}, 2, 2, Bitmap.Config.RGB_565);
mBG = new BitmapShader(bm, Shader.TileMode.REPEAT, Shader.TileMode.REPEAT);
Matrix m = new Matrix();
m.setScale(6, 6);
mBG.setLocalMatrix(m);
}
// //google api的画法
// @Override
// protected void onDraw(Canvas canvas) {
// canvas.drawColor(Color.WHITE);
//
// Paint labelP = new Paint(Paint.ANTI_ALIAS_FLAG);
// labelP.setTextAlign(Paint.Align.CENTER);
//
// Paint paint = new Paint();
// //设置是否使用双线性过滤来绘制Bitmap,图像在放大绘制的时候,默认使用的是最近邻插值过滤,这种算法简单,但会出现马赛克现象;而如果开启了双线性过滤,就可以让结果图像显得更加平滑
// paint.setFilterBitmap(false);
//
// canvas.translate(15, 35);
//
// int x = 0;
// int y = 0;
// for (int i = 0; i < sModes.length; i++) {
// // draw the border
// paint.setStyle(Paint.Style.STROKE);
// paint.setShader(null);
// canvas.drawRect(x - 0.5f, y - 0.5f, x + W + 0.5f, y + H + 0.5f, paint);
//
// // draw the checker-board pattern
// paint.setStyle(Paint.Style.FILL);
// paint.setShader(mBG);
// canvas.drawRect(x, y, x + W, y + H, paint);
//
// // draw the src/dst example into our offscreen bitmap
// int sc = canvas.saveLayer(x, y, x + W, y + H, null);
// canvas.translate(x, y);
// canvas.drawBitmap(mDstB, 0, 0, paint);
// paint.setXfermode(sModes[i]);
// canvas.drawBitmap(mSrcB, 0, 0, paint);
// paint.setXfermode(null);
// canvas.restoreToCount(sc);
//
// // draw the label
// labelP.setTextSize(20);
// canvas.drawText(sLabels[i], x + W / 2, y - labelP.getTextSize() / 2, labelP);
//
// x += W + 10;
//
// // wrap around when we've drawn enough for one row
// if ((i % ROW_MAX) == ROW_MAX - 1) {
// x = 0;
// y += H + 30;
// }
// }
// }
//
// // create a bitmap with a circle, used for the "dst" image
// static Bitmap makeDst(int w, int h) {
// Bitmap bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
// Canvas c = new Canvas(bm);
// Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
//
// p.setColor(0xFFFFCC44);
// c.drawOval(new RectF(0, 0, w * 3 / 4, h * 3 / 4), p);
// return bm;
// }
//
// // create a bitmap with a rect, used for the "src" image
// static Bitmap makeSrc(int w, int h) {
// Bitmap bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
// Canvas c = new Canvas(bm);
// Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
//
// p.setColor(0xFF66AAFF);
// c.drawRect(w / 3, h / 3, w * 19 / 20, h * 19 / 20, p);
// return bm;
// }
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.WHITE);
Paint labelP = new Paint(Paint.ANTI_ALIAS_FLAG);
labelP.setTextAlign(Paint.Align.CENTER);
Paint paint = new Paint();
paint.setFilterBitmap(false);
canvas.translate(15, 35);
int x = 0;
int y = 0;
for (int i = 0; i < sModes.length; i++) {
// draw the border
paint.setStyle(Paint.Style.STROKE);
paint.setShader(null);
canvas.drawRect(x - 0.5f, y - 0.5f, x + W + 0.5f, y + H + 0.5f, paint);
// draw the checker-board pattern
paint.setStyle(Paint.Style.FILL);
paint.setShader(mBG);
canvas.drawRect(x, y, x + W, y + H, paint);
// 使用离屏绘制
int sc = canvas.saveLayer(x, y, x + W, y + H, null);
canvas.translate(x, y);
canvas.drawBitmap(makeDst(2 * W / 3, 2 * H / 3), 0, 0, paint);
paint.setXfermode(sModes[i]);
canvas.drawBitmap(makeSrc(2 * W / 3, 2 * H / 3), W / 3, H / 3, paint);
paint.setXfermode(null);
canvas.restoreToCount(sc);
// draw the label
labelP.setTextSize(20);
canvas.drawText(sLabels[i], x + W / 2, y - labelP.getTextSize() / 2, labelP);
x += W + 10;
// wrap around when we've drawn enough for one row
if ((i % ROW_MAX) == ROW_MAX - 1) {
x = 0;
y += H + 30;
}
}
}
// create a bitmap with a circle, used for the "dst" image
// 画圆一个完成的圆
static Bitmap makeDst(int w, int h) {
Bitmap bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(bm);
Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
p.setColor(0xFFFFCC44);
c.drawOval(new RectF(0, 0, w, h), p);
return bm;
}
// create a bitmap with a rect, used for the "src" image
// 矩形右下角留有透明间隙
static Bitmap makeSrc(int w, int h) {
Bitmap bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
Canvas c = new Canvas(bm);
Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
p.setColor(0xFF66AAFF);
c.drawRect(0, 0, w * 19 / 20, h * 19 / 20, p);
return bm;
}
}
简单的刮刮卡案例
public class XfermodeEraserView extends View {
private Paint mPaint;
private Bitmap mDstBmp, mSrcBmp, mTxtBmp;
private Path mPath;
public XfermodeEraserView(Context context) {
this(context, null);
}
public XfermodeEraserView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public XfermodeEraserView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
//初始化画笔
mPaint = new Paint();
mPaint.setColor(Color.RED);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeWidth(80);
//禁用硬件加速
setLayerType(View.LAYER_TYPE_SOFTWARE, null);
//初始化图片对象
mTxtBmp = BitmapFactory.decodeResource(getResources(), R.drawable.result);
mSrcBmp = BitmapFactory.decodeResource(getResources(), R.drawable.eraser);
mDstBmp = Bitmap.createBitmap(mSrcBmp.getWidth(), mSrcBmp.getHeight(), Bitmap.Config.ARGB_8888);
//路径(贝塞尔曲线)
mPath = new Path();
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
//绘制刮奖结果
canvas.drawBitmap(mTxtBmp, 0, 0, mPaint);
//使用离屏绘制
int layerID = canvas.saveLayer(0, 0, getWidth(), getHeight(), mPaint, Canvas.ALL_SAVE_FLAG);
//先将路径绘制到 bitmap上
Canvas dstCanvas = new Canvas(mDstBmp);
dstCanvas.drawPath(mPath, mPaint);
//绘制 目标图像
canvas.drawBitmap(mDstBmp, 0, 0, mPaint);
//设置 模式 为 SRC_OUT, 擦橡皮区域为交集区域需要清掉像素
mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_OUT));
//绘制源图像
canvas.drawBitmap(mSrcBmp, 0, 0, mPaint);
mPaint.setXfermode(null);
canvas.restoreToCount(layerID);
}
private float mEventX, mEventY;
@Override
public boolean onTouchEvent(MotionEvent event) {
super.onTouchEvent(event);
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
mEventX = event.getX();
mEventY = event.getY();
mPath.moveTo(mEventX, mEventY);
break;
case MotionEvent.ACTION_MOVE:
float endX = (event.getX() - mEventX) / 2 + mEventX;
float endY = (event.getY() - mEventY) / 2 + mEventY;
//画二阶贝塞尔曲线
mPath.quadTo(mEventX, mEventY, endX, endY);
mEventX = event.getX();
mEventY = event.getY();
break;
}
invalidate();
return true; //消费事件
}
}