Prerendered means every variant is composed in advance and served as an image. The page loads a picture; there is nothing to run.
A 3D engine means the product is assembled in the browser at the moment of viewing, from a model and materials.
What each is good at
| Prerendered | 3D engine | |
|---|---|---|
| Page speed | as fast as any image | depends on the device |
| Photorealism | as good as your renderer | as good as the browser allows |
| Endless configurations | no | yes |
| Works on an old phone | yes | sometimes |
| Cost per new finish | one render pass | none |
Choosing
If the range is variants, prerender. The list is finite, the images are cacheable, and the buyer gets a photograph-quality picture at photograph speed.
If the range is configurations, fitted, parametric, endless, a live engine is the only option, because there is no finite list to render in advance.
Most furniture catalogues are variants and get sold a 3D engine, which is how a product page ends up slower than the competitor’s and no more convincing.
The third answer
Both, in different places. Prerendered images on the product page, where speed decides whether anyone stays; a live configurator one click deeper, for the person who has already decided to design something.
