CS3D is an impressive and capable project, and it's certainly further along as far as presentation is concerned (thought I could certainly help an "F" engine project surpass it there).
But somehow CS3D just doesn't capture my imagination the way Tenebrae II, WFF, Qubism, Fusion and other Q2 BSP engine derivitaves... Which certainly doesn't mean that CS3D, CEL, Genesis 3D, WorldForge, Ogre 3D, ExNihilo, Sylphis 3D, Reality Factory, NeoEngine, AXiom, Panda3D -- or anyone of a dozen other amazing open source projects can't be "it"...
I just have more confidence on an engine that offers some degree of legacy support, the robust character and 'feel' of id Software BSP engines, and has productive capable talent behind it.
More people mod and have worked on id Software derivative engines then any other because virtually every engine out there is or was derived from an id engine -- it's just a hunch but I think staying as close to the original track of the legacy of 3D engines will ultimately yield the most fruit in of the 'Linux Of Engines' variety...
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