Systems and methods disclosed herein provide drawing assistance to a user that improves the user's ability to draw accurate perspective drawings. In general, a drawing assistance system provides a homography that annotates guidelines over an image and connects lined features of the image to a corresponding vanishing point. More specifically, the homography provides a perspective grid to the user that assists the user in adding drawing strokes to a drawing using the proper perspective. In addition, the drawing assistance system can adjust a user's drawing stroke to properly align with a vanishing point. Further, in some embodiments, the drawing assistance system allows a user to add an asset into a drawing such that the asset is displayed in the proper perspective, even after a user moves the asset within a drawing.