Hi All!

We have been struggling with this issue for months and we are wondering what is the reason for the size discrepancy in houdini?

When you drop a box, it is a meter.

When you drop a pig head, it is the size of a car. Not the side of a pig head. Same goes for the other drop-able assets like squib.

When you groom at cat at the size of a cat, the tools do not work as expected, for instance, the comb node cannot predictably paint normals or any vectors at this scale(see my attached video). You have to paint at the size of a 10 ton monster cat.

You also need to pump the density to ridiculous values to see a decent amount of furs.

When you drop a camera, it is the right size relative to the meter box. When you drop a light, it is a meter. So on the rendering, lighting, and camera size the scene is correct. The camera F-stop and focus distance makes sense spacially, because 1 digit means 1 meter.

This is quite frustrating because we are trying to work to real world scales as defined by houdini, but then they scale all their assets up by 10 and all the tools work better at 10x scale.

There are workarounds but i think it is very confusing for new users to bring in their model, scale it to real world size, start painting then nothing happens.

Here is a video of the comb and paint node problem, as if i was a new user trying to use H17.

I agree that this is confusing. For examples, complex bullet sims of things about 1m in size result in collisions jittering all over the place and never settling. So you have to scale up 10x and scale all your forces and it's fine. At this point I am considering just telling my students to do everythng at 10x scale.

Similar behavior with the paint node, frustrating that this is something that we have to deal with. It makes the learning curve that much harder for new users and then for studios to really put Houdini at the top of their pipeline.

Paint node behavior at smaller scales should be fixed in the latest build.

While I understand the frustration of the OP, being there myself several times when trying sims at small scale, I would not blame “conflict of interest” I think is merely difficult to design a software that scales appropriately that works on both little animal and big cities scales. Basically most 3d software I know end up with this problem.

One of the issues I have is also the difference in scale of Houdini's own test geo. Frustrating for a new user to get comfortable with ( lets use fur in this case ) on test get and then port that to something thats at an actual scale. (comparing the difference between the pig head and the “real” size of Tommy's head.