The P function is especially common in e.g. Freetype code that works
with both the integer-pixel (X,Y) coordinates used by the stdlib image
package and sub-pixel (X,Y) coordinates used by its raster package.
Change-Id: I68be8ca71ceb24f40277ecc39a0896323f6671f5
Reviewed-on: https://go-review.googlesource.com/13652
Reviewed-by: Rob Pike <r@golang.org>
These mirror the image.Point methods in the standard library.
Change-Id: I7309af308a8182e325af20b47341f72703cbc95a
Reviewed-on: https://go-review.googlesource.com/13603
Reviewed-by: David Crawshaw <crawshaw@golang.org>
