Workshop · Note 6
Drawing a mountain in code.
Katun's pictures are drawn by the game itself: on paper by day, in hearthlight at night.
Katun's pictures were not drawn and scanned. The scene is code that builds the katun layer by layer: sky, far mountains, peaks, meadow, hut, herd. The same scene runs in the game, and we rendered the pictures for this website from it, too.
Paper by day, hearthlight at night
We settled on two styles: "Paper ridges" by day, cut paper with a rust-coloured sun and sage meadows, and "Hearthlight" at night, with an indigo sky, the hut's warm door, stars and fireflies. The switch follows sunset and sunrise where you are.
The scene has four colour stages, taken from our art board: paper by day, golden hour, dusk and hearthlight at night. Everything in between is blended. So there is no hard cut when day turns into evening.
One shape, two lights
Day and night share the same drawing. What changes are the colours of each layer (sky, peaks, shade, meadow, roof, door) and the light: stars, moon, fireflies, the glow of the door, a bright rim along the edges. The scene draws the weather and the season too; in winter the herd stands down in the stable in the village.
Paper casts crisp shadows
One detail: cut paper casts crisp shadows, not soft ones. That suited the style, and it has a practical reason. Soft shadows took 2.2 to 2.6 milliseconds per frame, crisp ones 1.0 to 1.2 (measured on 5 November 2026 on a full iPhone frame). Since then the shadows have been crisp, and the scene stays light.
A crop, not a camera
The scene is drawn on a fixed grid of 390 by 844 points, the size of an iPhone screen. For the pictures here we cut out crops: the whole valley with the spring and the stone on the left, the hut and the pastures on the right, and the hut up close. It is the same drawing, just a different crop.
The herd is code, too
The portraits of the animals, the lambs and Baba are drawn by the same code. For the website we have a small tool that writes the scene to image files on the Mac: swift run KatunScenePreview. That way the pictures here and the pictures in the game are the same picture.
More notes
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