Hey all you Houdini guys and gals,

I know this would be more in the realms of more architectural packages like 3ds Max or autoCAD etc. but if I want to accurately model a building from floor plans with measurements in mm's how do I do this in Houdini? I can't find any sort of units setup function where you can choose mm's, cm's, metres or feet and inhes etc. Can you only measure things using Houdini's native units? If so how do you model accurately from plans etc.?

Cheers guys…

A Houdini unit is just that - a generic unit. You determine it to be whatever you want. You're correct, with CAD/CAM programs, there's a definite value in maintaining an internal relationship to the real world, since typically you're designing something that will need to be physically constructed.

CAD/CAM isn't really what Houdini is focused on - it's a 3D animation and FX program. As mentioned, you're free to determine yourself how you want the scaling to work. However, be careful to not make, say, 1 unit equal to 50 meters if your goal is to fly along the cracks in the floor of the basement. Try to pick a scale appropriate to the scale you'll be working at.

Cheers,

J.C.

Just a small Addendum to what JC wrote. Its true that Houdini is unitless and that 1 == meters, mm, km, beer cans, etc.

However this isn't the case with DOPs; in DOPs units matter. In DOPs, distance is a meter and mass is kilograms. For example a gravity force of -9.8 is in m/s^2.

Now working with meters and kilograms may be a pain so you can tell Houdini what 1 “unit” actually is and it will do the conversions…to some degree for you. Like if you tell Houdini that 1 unit is a centimeter when you put down a Gravity Force DOP it will default to -980 (which is cm/s^2).

You can set this in the Settings > Preferences > Hip File Options.

okay cool, I get it. I have building CAD data in mm's so if I just convert it to metres all should be good….I'm building a model to blow up in DOPs….thanks for the heads up…