Question

I am trying to rotate a bitmap when drawing it to a canvas. The problem is that when I call canvas.rotate(90) anything that is drawn after that does not actually get drawn. Running the following code will draw nothing to the screen when I have the rotate call in there. If I take out the rotate call it shows up fine. Why would the rotate call stop the bitmap from showing up on the canvas?

        canvas.save();
        canvas.rotate(90);
        canvas.drawBitmap(leaves, null, leafRect, bitmapPaint);
        canvas.restore();

Answer 1

By default, rotate() will rotate the canvas from the exact center. You probably want to rotate from the center of your bitmap.

    canvas.save();
    canvas.rotate(90, leafRect.x + (leafRect.width / 2), leafRect.y + (leafRect.height / 2));
    canvas.drawBitmap(leaves, null, leafRect, bitmapPaint);
    canvas.restore();

More info at the docs rotate(angle, x, y)