Can only draw full screen image

[Johennes]

The image method currently only allows to redraw the whole screen.

    def image(self, img, rotation=None):
        ...
        imwidth, imheight = img.size
        if imwidth != self.width or imheight != self.height:
            raise ValueError(...
        ...
        self._block(0, 0, self.width-1, self.height - 1, pixels)

Especially on lower end boards it seems advantageous to be able to draw smaller images in part of the screen only without having to refresh the whole screen.

I would like to suggest to add two new arguments to the method for specifying the origin

    def draw(self, image, x0=0, y0=0):

to drop the if imwidth != self.width or imheight != self.height: check and to adapt the call to _block so that the image's size is passed in instead of the screen size.

    self.display._block(x0, y0, x0 + imwidth - 1, y0 + imheight - 1, pixels)

Instead of removing the size check, one could also replace it with a check to ensure that the image is not bigger than the screen size.

Happy to submit a pull request if this makes sense.

[ladyada]

yep please submit a PR to image(), you can add extra kwargs for x, y.