> ## Documentation Index
> Fetch the complete documentation index at: https://hyperframes.heygen.com/llms.txt
> Use this file to discover all available pages before exploring further.
# When to generate artwork
> Code-drawn wins for UI, type, geometry, and 3D; illustration-led hero art comes from an image model, animated as layers.
Your Level 1 music slideshow cut real photos to the beat — there was real art to work with. This chapter is for the opposite case: a hero character, a painterly scene, sculptural objects that don't exist as a photo or a footage capture yet.
Code-drawn HTML/CSS/SVG excels where the medium is native: UI mockups, typography, geometric shapes, charts, pixel art, and 3D via Three.js. For **illustration-led** hero art — characters, painterly scenes, sculptural objects — hand-drawn SVG tops out at clipart quality no matter how well you prompt. The fix is a hybrid:
> Generate the hero artwork as an image (via the media-use skill's image generation), then animate it with code. Anything that must move independently — eyelids, light beams, drawing lines — stays a code layer on top of the static art.
Three rules that make this work:
1. **Generate on a solid contrasting background** (magenta works) so the subject keys out cleanly. A light subject on a light background gets silently eaten.
2. **Key flat vector-style art with a chroma key** (`ffmpeg colorkey`), not AI background removal — `remove-background`'s matting model is tuned for photographic and human subjects and reads flat art unreliably, sometimes keeping the background instead of the subject. Reserve `remove-background` for photographs.
3. **Put a restraint clause in the generation prompt** ("minimal, lots of negative space") — image models fill the frame by default, and a busy generated texture reads as cheap as bad vector art.
## The difference, side by side
The same brief — four people arm in arm, warm gradient sweaters, flat-illustration style — built both ways. Same animation beats, same craft layer (lighting, atmosphere, grade); the only variable is where the figures came from.
*Hand-drawn SVG figures — clean, but the proportions and gesture read as clipart.*
*Generated illustration animated as layers — real anatomy and editorial shading; the animated line still passes behind the figures because the artwork was keyed to transparency.*
**Capstone thread** — the [Level 7 film](/prompting/capstone)'s Surface region rides on generated artwork: a palette-neutral mural duotoned live by CSS from the composition's two variables, so even the raster re-skins on a `--variables` render (cut from the film, below).
This is the clause in the [full capstone prompt](/prompting/capstone#the-full-prompt-verbatim) that buys the piece — prompt language you can lift for your own video:
> \[…] over a **generated-artwork backdrop** — a flat abstract mural evoking motion trails, generated **palette-neutral (grayscale) and duotoned live by CSS** from the two variables so it re-skins with everything else. **The mural is a full-frame, screen-fixed backdrop: it never moves on screen — the widening iris circle alone reveals it already in place at full frame \[…] and it exits by fading out.**
*That clause, rendered — the region cut from the finished film.*
*Next: [VFX and liquid glass](/prompting/vfx-and-liquid-glass) — device mockups, frosted glass, and cinematic effects for when the layer on top needs its own spectacle.*