Trace to Draw: Lightbox

Trace to Draw puts a picture under your paper so you can practise proportion and composition.

TWO WAYS TO TRACE
• Lightbox — the picture stays on the screen and you lay thin paper on top of the phone and trace what shows through. Best for small drawings and thin paper. No camera is used.
• Camera — prop the phone above your paper, and the screen shows your paper with the picture laid over it. Best for larger paper and canvas.

THE PROPORTIONS NEVER CHANGE
Tracing is about proportion. If the picture on screen is stretched even slightly, the drawing you make from it is wrong, and no amount of careful line work will fix that.

So this app has only one zoom number. Pinching scales width and height together, always. There is no control anywhere that stretches one side, because there is no code for it. The ratio of your picture is shown next to the zoom, so you can check it yourself.

CONTROLS
• Opacity — set how strongly the picture shows through your paper
• Contrast — make faint lines easier to follow
• Black and white
• Flip
• White background for lightbox tracing
• A 3x3 or 4x4 grid laid over the picture
• Reset all — one button puts every adjustment back

LOCK
Lock pins the picture where it is, so a knock does not move what you have already lined up. While locked the controls fold away, and unlocking takes a press and hold rather than a tap. The app stays upright at all times, so turning the phone never re-lays out the screen mid-trace. Leaving the screen while locked asks first.

TURNING THE PICTURE
Two fingers can also turn the picture, which helps when your paper is not square to the phone. Anything within three degrees stays straight, so a wobble while you zoom never tilts it, and while it is turned the angle is shown next to the zoom.

WORKS OFFLINE
Everything runs on your phone. There is no account, no sign-up and no server, and it works with no signal at all. Your pictures are never uploaded.

NOTHING IS LOCKED
Your own pictures, any length of session, every adjustment — there is no purchase in this app at all.

WHAT TRACING IS FOR
Tracing is a way to practise proportion and composition, and to warm up. It is not a way to pass work off as your own.