replaces the current picture displayed by the glyph, resizing the new
picture to fit the glyph's current size.
newPicture :: Glyph -> Picture -> IO ()
replaces the current picture and resizes the glyph such that
it is at least the size of the new picture's bounding box in both directions.
addPicture :: Glyph -> Picture -> IO ()
Adds a picture by overlaying it on top of the glyph's current
picture. Overlay is done by matching up the origins of the two
pictures. Resulting picture is resized to fit the current size of the
Same as for setResizeablePicture, but in addition parameterised
over the picture to use for computing the new natural size of the
glyph. The glyph may resize as a result.
resizeGlyph :: Glyph -> Size -> IO ()
change the current size of the glyph. If the glyph's current picture
is a ResizablePicture, the new size will be applied to create the
new picture to display. Otherwise, the glyph's current picture will be
scaled to fit the new size.