OTOY Forums

It is strictly connected with what Frank wrote on World coordinates for displacement:

is possible to make displacement input as functional as texture (green input) so that we could connect the gradient node to displacement and then use random color node to randomize displacement texture over instances?

So my personal request is very specific to being able to have our displacement textures use World Space Coordinates -- so that ultimately we would be able to make completely different-shaped instances. I do believe that Goldorak or Marcus at one point said this should be doable once we have OSL...

I also requested update on this feature last night in the 3.0.6 Test thread: viewtopic.php?f=33&t=59760&start=20

FrankPooleFloating wrote:So my personal request is very specific to being able to have our displacement textures use World Space Coordinates -- so that ultimately we would be able to make completely different-shaped instances. I do believe that Goldorak or Marcus at one point said this should be doable once we have OSL...

I also requested update on this feature last night in the 3.0.6 Test thread: viewtopic.php?f=33&t=59760&start=20

WorldDisplacement..jpg

It's not possible at the moment, because we pre-calculate some information of the displacement triangles based on the displacement texture itself and this information is stored with the displacement triangle. We might be able to do different texture projections for UV triangles, but that would require us to do some major changes in the displacement intersection test itself. We are planning to have a look at displacement triangles in the future, but not in the near term.

Although OSL does provide some functions to control displacement in the standard, we can't think of any way to integrate them into the current path-tracer structure, which is why these functions will not work in Octane with OSL support. To understand the problem: Displacement mapping is part of ray-tracing which is done before shading is done. At the point OSL stuff is evaluated, ray-tracing is already finished and can't be influenced anymore.

Marcus,

So nothing like "gradient node" for displacement is possible to do the trick to randomize displacements over instances?

smicha wrote:Marcus,

So nothing like "gradient node" for displacement is possible to do the trick to randomize displacements over instances?

No, not at the moment and in the near future.

I believe you when you say this is not currently possible, though in my mind, I keep asking why it can't take world coord of a texture and store that, for each triangle, before the shading happens... you don't need to respond to that Marcus. I will continue to dream of a day when we can displace instances uniquely...

But please, my Octane brothers and sisters, this will never become a feature unless others (beyond just me and smicha) show some kind of interest in having this -- the ability to make instances of leaves, rocks, dog turds, whatever, be physically different from one another. I urge you all to speak up as we move forward, or there will be little motivation for Marcus & Co to make this happen.