Can AI render a hand-drawn sketch?

A phone photo of a sketch on a drawing board is a completely normal input. The model reads the line work as geometry — walls, openings, roof lines, the horizon — and builds a photorealistic image on that structure. You do not need to scan it, redraw it in CAD, or clean it up in Photoshop first.

What makes the difference is contrast and clarity rather than artistic quality. Firm lines on white paper, photographed flat with reasonable light, read well. A faint pencil sketch photographed at an angle in a dim room gives the model an ambiguous starting point, and ambiguity is where invented detail creeps in. Straightening the photo and raising the contrast takes ten seconds and noticeably improves the output.

Sketches with heavy shading and hatching are a mixed case. The model can read tonal shading as material variation, which is sometimes exactly what you want and sometimes produces texture where you meant shadow. If the result surprises you, a cleaner line-only version is usually the fix.

The same path works for CAD line work, a Revit hidden-line export, or a SketchUp viewport in monochrome. From the model point of view they are all line drawings, and they all render the same way.