Android Canvas：如何绘制具有自己旋转和枢轴点的多个位图？

Question

Suppose that I have two bitmaps that I'd like to draw on a Canvas of a View . The twist is that I want to draw the first bitmap rotated 30 degrees clockwise around one pivot point, and I want to draw the other bitmap 45 degrees counter-clockwise around another pivot point.

I have the following stub in mind:

canvas.save(Canvas.MATRIX_SAVE_FLAG);
canvas.rotate(30, pivotX, pivotY);
canvas.drawBitmap(bitmapOne, x1, y1, antiAliasPaint);
canvas.rotate(-75, otherPivotX, otherPivotY);
canvas.drawBitmap(bitmapTwo, x2, y2, antiAliasPaint);
canvas.restore();

Edit:

Confirmed that it doesn't work. It just results in rotating the same canvas.

Will I have to create 2 Bitmap s, rotate bitmapOne in one new Bitmap object, rotate bitmapTwo in the other, and draw them as normal in the destination canvas?

Answer 1

Do it this way:

canvas.save(Canvas.MATRIX_SAVE_FLAG);
canvas.rotate(30, pivotX, pivotY);
canvas.drawBitmap(bitmapOne, x1, y1, antiAliasPaint);
canvas.restore();

canvas.save(Canvas.MATRIX_SAVE_FLAG);
canvas.rotate(-75, otherPivotX, otherPivotY);
canvas.drawBitmap(bitmapTwo, x2, y2, antiAliasPaint);
canvas.restore();