Paint changes cleanly because the shading was never flattened into it
In short
- Flat paint establishes the chosen colour, while separate body layers preserve drawn changes in lightness.
- Glass, lamps, tyres, trim and badges remain fixed instead of inheriting the paint colour.
- The live renderer applies measured differences from the original drawing rather than adding generated shading.
- Very light and very dark colours need limits so adjacent body shapes do not merge.
I draw the light before the site ever sees the car. The preparation step measures the body layers and records how each one differs from the main paint. The builder can then move those differences onto another colour without pretending it knows where a new reflection belongs.
Why keep car paint and shading on separate layers?
Separate layers let the paint colour change while preserving the drawn highlights and shadows that describe the panels. A flattened body would either keep the original colour or become a featureless block when recoloured.
The distinction is visible in the four-stage drawing viewer. Flat colour arrives before shading and detail. It is useful precisely because it looks unfinished. You can see which work the later layers add.
What happens if the car uses one flat paint layer?
One flat paint layer keeps the silhouette but loses the light that separates bonnet, wings, bumper and arches. The car reads more like a cut-out than a shaped body.
A colour picker cannot recover those decisions after the drawing has been flattened. It can replace orange with blue, but it does not know which blue belongs on the top of the bonnet or under an arch. That work has to exist in the source layers first.
| Part | Follows chosen paint | Keeps its own material colour |
|---|---|---|
| Main body and body shades | Yes | No |
| Glass and lamps | No | Yes |
| Tyres, grille and trim | No | Yes |
| Badge and plate detail | No | Yes |
How does the live builder preserve the original shading?
Each prepared body layer stores its measured lightness offset and colour-strength ratio against the source paint. The renderer applies those relationships to the customer's selected colour.
The calculation uses OKLab lightness because the visible job is to keep the difference between lighter and darker painted panels. The hue stays with the customer's selection. This is not a second drawing mode. The preview and print still pass through the same renderer, as the Photoshop-to-print guide explains.
Why do very light and dark paints need limits?
Very light paint can run out of room for a brighter highlight, while very dark paint can swallow a darker shadow. The renderer limits the lightness range and preserves a minimum separation between body shades.
Dark paint gets one extra decision. Below the recorded threshold, pushing every shadow farther down would merge panels into black, so the direction changes and the shapes remain visible. That is a display safeguard around the original drawing, not newly generated light.
Why do lamps, glass and badges stay fixed?
Those parts are not body paint. They retain their own artwork so a colour change cannot repaint a tyre, lamp lens, grille, badge or registration plate.
Grey and white source cars make this separation harder because pale headlamp glass can measure like paint. That is why layer naming and visual review remain part of preparation. A plausible colour cluster is not allowed to overrule the visible car.
Try the result in the live builder. The hue will change. The useful check is whether the car keeps its panels and non-paint details when it does.
What supports this Photoshop workflow?
Adobe documents layers, masks and adjustment layers as ways to keep edits separate and revisable. This shop's specific colour relationships come from its own prepared artwork and renderer rather than from a generic Photoshop preset.
Adobe's current guidance covers nondestructive editing and targeted layer masks. The live implementation is recorded in the site's shading and renderer code. It preserves relationships already drawn and does not infer an unseen surface.
Questions people actually ask
- Why should paint and shading be on separate Photoshop layers?
- Separate layers let the base paint change while the drawn highlights and shadows keep their jobs. Flattening them together would either lock the original colour in place or turn a new colour into one flat shape.
- Does the website generate new shading for each paint colour?
- No. The renderer applies measured lightness and colour relationships taken from Jonathan's original body layers. It moves the shading already drawn for that car rather than inventing new reflections or hidden panel detail.
- Why do very dark car colours need different shading treatment?
- Darkening an already dark paint can push several body layers into the same near-black result. The renderer changes the lightness direction below a defined threshold and keeps a minimum gap between adjacent shades so the panels remain readable.
- Which parts of a car drawing should not change with the paint?
- Glass, lamps, tyres, grille details, badges and number-plate artwork normally remain fixed. Painting those parts with the body would make a quick colour change alter materials and identity details that were never paint.
Written by Jonathan in Derby. Last updated .