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Displacement problem with alembic camera


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Hi, 

I have a problem rendering some geometries with displacement using a camera exported from Maya in alembic format.

If I render the scene using this one, there aren't any displacement visible but if I render it using a native camera from Houdini, there aren't any problem.

Are there any solution ?

Displacement Problem.rar

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two things: never scale a camera.  if you get an alembic camera, first thing you should do is verify it's not scaled.  you can do this by putting a unit sphere (as polymesh) as a child to your camera, then object merging it into a geo in world space (ie at the /obj level).  then see how big it is.  then insert a null above the camera to undo that scale (so if the geo is .1 radius, add a scale of 10).

 

it's a huge drag with alembics -- particularly importing via the file dialog.  for this reason, it's much better to create an alembic camera import node that can exclude the scale and generally make updating a billion times easier.

 

 

and then the other aspect is always displace is object space.  by default it's in "current" space (which is camera space in houdini).  this means that scales on your object are ignore and the scale of the camera is used.  generally speaking, you want your displacements to scale with any object scales you have.  if you're using the displace along normals, you should toggle on the object space option.  this will actually very likely fix your problem here, but it's possible you'll run into other problems still with a scaled cam (volumes are severely affected as well as lighting)....

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Thank's a lot for your answers.

I'll try to do as you say for my next shots.

And for the problem with my displacement, it doesn't seem to be solved :(

I found an alternative by rendering using Clarisse my ground with the displaced, and it worked.

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