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I often have multiple states of an object and will show/hide during an animation by animating the 'Object Dissolve' envelope(channel). However in octane this causes many problems and unpredictable renders. One of which is that if more than one object occupy the same space, and one is dissolved, it creates odd artifacts where the two objects intersect (even though one is 100% dissolved). It also sometimes causes the objects to render as if they are not smooth (I see the tessellation of the polygons).

With that said, am I not doing visibility correctly? I know I can change visibility via 'opacity' per material, but my objects often have dozens of materials and having dozens of channels to animate is not a solution.

I know I can also set the objects scale to 0, but I am afraid this might cause motion blur issues if an object's scale changes from 0 to 100% over the course of one frame.

Any ideas?
Thanks!

Ok, I seem to have made some headway on why I don't get consistent smoothing on my models although I still get artifacts on points where the meshes intersect if one is dissolved.

Not sure if this is a bug but if I save my scene while in 'Vertex' shading display mode, next time when I open it if I start IPR or do a render the mesh is not smooth, while if I switch to 'Smooth Shading' view in lightwave Layout and THEN hit render or IPR, the mesh is smooth! See image below. Why would it matter to Octane how my preview window is set and what mode i'm in?

Good questions. I've had the same issues with artifacts where a dissolved object intersects a visible one.
I tried using dissolve again recently and it caused a massive slow down.

I normally transform objects way off frame instead of scaling to 0, I guess you get the same result. Pain with MB as you mentioned... maybe have to render an overlapping set of frames, one with the object, one without, then fade in post?

Man that's unfortunate, I was hoping I was just doing it wrong. I've been troubleshooting for a better part of the day with nothing to show for it. I really have no easy way to do it without using dissolve as I have a bunch of characters passing things to one another and putting sports gear on and off.

My only though is to use the scale to 0 method and add motion blur in post. While its not nearly as good it will be blurring the visible stuff only without knowing the actual motion of the pixels. The trouble will come if i try and edit the timing of the animations and having 'scales' occur over more than 1 frame (if I increase frame rate for example).

I also believe this is a bug. I recently had a completely dissolved character walk "through" a normal character and got a weird caustic effect shining on the wall behind them!

I also have noted the tessellation issue in a scene I rendered that had water geometry from a stream that overlapped with land. The water was specular and smooth, but the overlapping polys were always tessellated which ruined the reflection effect.

Rev wrote: Not sure if this is a bug but if I save my scene while in 'Vertex' shading display mode, next time when I open it if I start IPR or do a render the mesh is not smooth, while if I switch to 'Smooth Shading' view in lightwave Layout and THEN hit render or IPR, the mesh is smooth! See image below. Why would it matter to Octane how my preview window is set and what mode i'm in?

This is an old issue, but should be fixed now. What version of LightWave and the plugin are you using?

The problem is easy to understand: When the Layout doesn't have any viewport in solid mode, it doesn't compute the objects normals to be faster redrawing the viewports. This is why the objects are not smoothed in the IPR ... but the LightWave developers added some years ago an internal command in the Layout to compute the normals even if the viewports are not in solid mode. The Octane plugin use this command before load the scene, so it should work without problems even with the viewports in "vertex" mode.

I am testing a simple scene here with LW 2015.3 and the last build of the plugin and all seems to work fine. If you can send me a sample scene with this problem I could test it here to see if there is any kind of hidden problem.

-Juanjo

Rev wrote:I often have multiple states of an object and will show/hide during an animation by animating the 'Object Dissolve' envelope(channel). However in octane this causes many problems and unpredictable renders. One of which is that if more than one object occupy the same space, and one is dissolved, it creates odd artifacts where the two objects intersect (even though one is 100% dissolved). It also sometimes causes the objects to render as if they are not smooth (I see the tessellation of the polygons).

With that said, am I not doing visibility correctly? I know I can change visibility via 'opacity' per material, but my objects often have dozens of materials and having dozens of channels to animate is not a solution.

I know I can also set the objects scale to 0, but I am afraid this might cause motion blur issues if an object's scale changes from 0 to 100% over the course of one frame.

Any ideas?
Thanks!

Yes, the Octane object level dissolve (like the shaders level opacity) parameter works at shading level, and it doesn't work fine with overlapped geometry. Usually if you scale or translate one of the objects a bit (for example, scale one of the two overlapped objects to 0.99), the dissolve/opacity feature should work better.

About the rendering speed, an object 100% dissolved is loaded in the Octane scene like any other object, and Octane must shade it to know that it is full dissolved, so you are going to have a slower render performance that if for example you full disable it in the scene editor ... the object can be 100% transparent, but must be rendered to know that it is 100% transparent.

It is lot better and faster to scale one object to 0 (or put it far away in the scene) if you need to full dissolve it. To avoid the motion blur problems, you only need to set the animated key frames curves as "Stepped", as you can see in the attached image.

Anyway I will think in a solution for this issue in Octane 3, perhaps with a object enable/disable flag that can be enveloped.

-Juanjo

Thanks! Appreciate the replies.

I was using version 11.6.1 previously of Lightwave (updating older project) with Octane version 2.24.0.1. but I can verify that the problem is still there in 2015.3 although ONLY appears on initial launch (if scene was previously saved and opened with the viewport in Vertex view and only in IPR - making an actual render even in vertex mode looks fine. Afterwards it does fine even in vertex view.

Its not a big deal, I was just confused before since I though my ray epsilon or some other setting was wrong and kept changing that and not realizing it was because I was keeping my viewport in vertex view when rendering (in LW 11.6.1). Had I used 2015 i would not have noticed it probably.

Unfortunately offsetting geometry a small amount or scaling a small amount still produces artifacts although less of them since there is still 'some' overlap especially with objects with internals so I will use the scale to 0 method. Thanks for the suggestion on stepped keys, its a great idea! Would love a disable/enable for objects in a future version. I also use Cinema4D with Octane and in there I key frame the 'Visible in renderer' and it appears to work much better.

Thanks again,

I thought I'd put a reply in this thread to mention that I encountered the same issues, and also noticed that numerous intersections with dissolved objects will cripple Octane's performance (a common occurrence when the animator is utilizing part-body dynamics). Even knowing that octane must process the object to know whether or not it is visible, the expected behavior is that a 100% invisible object should be considered disabled for the renderer.

If only Lightwave's "active" checkbox were animatable...

The next build will have a new parameter in the custom object plugin that is an animatable float to control the object enable state. If this float is < 1.0, the object will be disabled, so now should be possible animate the "active" state of an object.

-Juanjo