Is possible to port Blender Internal Render as an addon/fork like Blender Game Engine (UPBGE)

[Okidoki]

Hmm… AFAIK the “cycles integration” in blender is an addon/extension. So the handleing of the materials etc… but cycles itself, even if available as standalone renderer, is integrated into blender (and written in C not Python ).

But so are other “integrations” like for example for LuxCoreRender (which has “only” official support for 4.5 and experimental fot 5.0… because the addon/extension API for the GUI changed a bit…).

Edit/Added:
And of course (i remembered replying to something similar ): using the the awesome forum search function (top right –icon)… there is some “recreating of…”:

How to make a standrd Blinn Material

You might check some of the discusion to “fake” this older kind of shader like for example: …or… …and there is always the awesome forum search function (top right –icon)…

Trying to replicate 2.79 Phong/Lambert shading

What needs clarifying? At the end, a lambert shader calculates the dotproduct of the surface normal (usually denoted N) and the (normalized) light direction vector, which points from the shaded point towards the lightsource (usually denoted L). Maybe it helps if you look at following post from Billie’s sketchbook: In the middle of that post, Billie made a shadernode setup which does the exact same thing, but he put more effort into naming things, which might make it easier to understand. W…

and even a raytracer in geometry nodes:

Creating a Ray Tracer in Geometry Nodes

This reminds me of the raytracer made within the scripting language of PovRay… …saying this… there was also something within blender… ( in 2.79 already ??)

( and again… PovRay )