plzxplainHow to use Construction
Construction is an Android portrait-specific checking tool. It draws classic head-proportion lines over a photo of your drawing or painting, so you can compare the placement of features before you keep refining them. The measurement stays on your device; the photo is not uploaded.
Available on Android
Construction currently needs the Android face detector included with the app. On iPhone and web builds, face detection is not available yet, so this tool cannot measure a portrait there.
Choose a clear portrait photo
Open Construction and choose Choose a photo or Take a photo. Photograph the artwork straight-on, with the face filling a useful part of the frame. A front-facing or nearly front-facing head gives the tool the best chance of finding reliable landmarks.
Strong profiles, heavy shadows, very small faces and unusually angled photos may be rejected. That is intentional: a line that looks precise but is based on an unreliable detection would be less useful than no line at all.
The portrait in the example below is large, well lit and close enough to front-facing for the detector to find a stable mesh. If the app cannot support the same confidence in your photo, it stops instead of drawing persuasive but unreliable lines.
Read the lines as a construction check
After the face is found, tap or pinch to inspect the canvas. Use Across to show the horizontal construction lines and Down to show the vertical relationships. Tap a line or its matching item in the list below to highlight it and read what it is checking.
The list shows the relationships that appear off first, followed by the checks that are sitting where expected. Treat both as prompts to look again: compare the drawing to both the overlay and your reference, then decide whether a relationship needs changing.
Know what not to over-trust
Construction is most useful for a first-pass proportion check, not for polishing a likeness by numbers. Small differences can come from a camera angle, expressive distortion in the reference, or the way you intentionally drew the head.
The hairline deserves particular caution. It is estimated from proportion because the face mesh does not extend to the top of the head. Use that line to help sketch the head shape; do not treat it as a measured fact. If the app says the irises are unclear, it will also flag that its tolerance is estimated—give small differences less weight in that case.
When the large relationships look sound, put the phone down and return to the painting. The tool should help you see, not replace the judgement you are practising.