The proposed fix updates the x axis offset variable in case the tile surpasses the limits of the destination image. Fixes golang/go#24657 Change-Id: I6bc52274a05dc41b058f6a6f1d0a304f1b20152d Reviewed-on: https://go-review.googlesource.com/104295 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>