Android給bitmap圖加上倒影效果

Android給bitmap圖加上倒影效果:

2. public static Bitmap createReflectedImage(Bitmap originalImage) {
4. // The gap we want between the reflection and the original image
5. final int reflectionGap = 4;
7. int width = originalImage.getWidth();
8. int height = originalImage.getHeight();
10. // This will not scale but will flip on the Y axis
11. Matrix matrix = new Matrix();
12. matrix.preScale(1, -1);
13. // Create a Bitmap with the flip matrix applied to it.
14. // We only want the bottom half of the image
15. Bitmap reflectionImage = Bitmap.createBitmap(originalImage, 0, height / 2, width,
16. height / 2, matrix, false);
18. // Create a new bitmap with same width but taller to fit reflection
19. Bitmap bitmapWithReflection = Bitmap.createBitmap(width, (height + height / 2),
20. Config.ARGB_8888);
22. // Create a new Canvas with the bitmap that's big enough for
23. // the image plus gap plus reflection
24. Canvas canvas = new Canvas(bitmapWithReflection);
25. // Draw in the original image
26. canvas.drawBitmap(originalImage, 0, 0, null);
27. // Draw in the gap
28. Paint defaultPaint = new Paint();
29. canvas.drawRect(0, height, width, height + reflectionGap, defaultPaint);
30. // Draw in the reflection
31. canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null);
33. // Create a shader that is a linear gradient that covers the reflection
34. Paint paint = new Paint();
35. LinearGradient shader = new LinearGradient(0, originalImage.getHeight(), 0,
36. bitmapWithReflection.getHeight() + reflectionGap, 0x70ffffff, 0x00ffffff,
37. TileMode.CLAMP);
38. // Set the paint to use this shader (linear gradient)
39. paint.setShader(shader);
40. // Set the Transfer mode to be porter duff and destination in
41. paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
42. // Draw a rectangle using the paint with our linear gradient
43. canvas.drawRect(0, height, width, bitmapWithReflection.getHeight() + reflectionGap, paint);
45. return bitmapWithReflection;
46. }