Sure you can pass it in - but it doesn't do anything. :) 

Besides, the -gate 1 switch in BJP's tool speeds up the process considerably already. 

You'd be surprised. I multithreaded my Mac version and even if you cut a minute build time down to 35 seconds, that speeds up iteration so it's totally worth it... 

Has anyone added the ability to use visdata (if present) to light.exe yet? I did it for MHColour and it was a HUGE boost, so it would definitely also be worthwhile for general lighting. 

I don't think so.

Go go go! That would be awesomely great. :) 

how does light work? i thought it was raytracing, so how would vis data speed it up? 

Light basically does a ray-trace from every light to every lightmap pixel on every surface in the map. I think there is already an optimization to reject surfaces that are outside the radius of the light (for linear falloff lights) but for lights with an inverse square falloff, a light theoretically has infinite range, so vis data could be useful to quickly reject polygons a light can't see. 

i originally just sort of imagined it as blasting out rays and pasting a light value on any walls it hit. i didn't know it did the entire map. o_o 

do the light tools not use radiosity? 

> Has anyone added the ability to use visdata (if present) to light.exe yet? I did it for MHColour and it was a HUGE boost, so it would definitely also be worthwhile for general lighting.

Doesn't bjp light do that already? I seem to remember one that does it. 

some of them do; for example i think lordhavoc's compilers do it.