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Deep_Thought
02-10-2016, 05:05 PM
Hi guys,

I am stuck with some noobie stuff: A 100% dissolved object fades into existence via envelope on the dissolve channel. The object itself fades in smoothly but its reflection in another object does not. It jumps from total invisibility in one frame to complete visibility in the next.

Am I missing something basic here?

djwaterman
02-10-2016, 07:16 PM
I thought I could answer this, but I just did a test and mine dissolves smoothly.

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What is your lighting set up?

objuan
02-11-2016, 12:43 AM
I seem to recall having some issues with this. At 100% dissolved the reflection was gone, but at 99%-1% not so much. Also Shadow Mapped shadows had issues. The shadows I think you can fix by using DP lights for soft lights. As to the reflections, I'm afraid my answer was to render a pass with my fading object all the way on, and a 2nd pass without my fading object - and then comp them/fade in AE.

Deep_Thought
02-11-2016, 05:20 AM
I thought I could answer this, but I just did a test and mine dissolves smoothly.

132365

What is your lighting set up?

You are right, your scene renders exactly as it should. This is good news. Now I know at least that Lightwave works fine and I just need to find the right setup.

The problem might be that my scene was created with Lightwave 3.5 for Amiga almost 20 years ago, then imported into Lightwave 5.5 for Windows about 10 years later and now again imported in Lightwave 11.6. I think there might be some strange setup data within the scene config that screws up the current rendering.

Danner
02-11-2016, 07:42 AM
The most reliable way to dissolve an object is to make two image sequences, one with, one without and fade it in post.

Deep_Thought
02-11-2016, 08:48 AM
I thought I could answer this, but I just did a test and mine dissolves smoothly.

Alright, now I am confused:

I took your scene and added my two objects. Your cube and my CPU fade smoothly, but the reflection of the CPU in the logo just pops into existence.

Could you render this on your machine and see if your output differs from mine:

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This is how it looks like on my system:

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It almost seems as if the CPU fades into existence but its reflection on the logo does the exact opposite. On the plane, however, the CPU reflection fades in as it should. Could there be some strange setting in the logo's surface? I did not find anything yet.

Edit: Attached wrong scene version.

spherical
02-11-2016, 04:30 PM
OK. Have yet to try the two scenes to compare, but stepped through the animation and am not seeing any timing difference between the CPU and its reflection in the grey (whatever it is, doesn't seem to be a cube, based upon the reflections and shadows). What I do see is that the lettering and especially the i dot, change at one frame when the CPU first appears. I'd try increasing the Ray Recursion Limit.

Deep_Thought
02-11-2016, 04:53 PM
What I do see is that the lettering and especially the i dot, change at one frame when the CPU first appears. I'd try increasing the Ray Recursion Limit.

Exactly! As soon as the dissolve value of the CPU is greater than 0.0% it seems as if some kind of placeholder reflection is calculated on the logo. It looks almost like some shadow. With the fading in of the CPU this shadow transforms from plain dark to the actual reflection. When the dissolve reaches 0%, the reflection on the logo is correct.

Also, the rendering environment of the logo surface seems to play a role. When the reflection options are set to Ray Tracing + Spherical Map, the above mentioned behavior takes place. When it is set to Ray Tracing + Backdrop, the "placeholder reflection" is always present (even before any change to the CPU dissolve value) and transforms into the actual reflection as the dissolve value drops to 0%.

I did some more tests with ray recursion limit as high as 64, but no change occured.

Edit: Mixed up dissolve values.

djwaterman
02-11-2016, 04:53 PM
I don't get a problem reflection-wise with your scene. Reflections are ramping up at the same rate as the dissolve. I'm using LW 2015. I'll try it in 11 and see if that shows the problem.

djwaterman
02-11-2016, 05:03 PM
I think it's just the dissolve curve in the graph editor, if you are talking about it popping into existence on the second frame after the dissolve begins. I put a bezier curve on it to ease out of the start position and let it fade up more slowly.


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spherical
02-11-2016, 05:40 PM
Yes, I was going to suggest that as well. Just tested the original scene and saw that happening. Doubling the RRL didn't change anything, but I'm not seeing the dramatic change in the logo/dot reflection at that frame either. However, I'm not getting the same reflection strength as exhibited in the video. I'm assuming that the missing images are the cause. So, I got nuthin'. :(

That said (not really related to the original popping problem), it seems that the plane reflection is far too strong. It's brighter than the metallic logo itself, even with the images not being applied. Nothing is 100% reflective, except for TIR in a Dielectric. Likewise, nothing is 100% diffuse; unless you are going for an unnatural look, then go nuts! :D

BTW, what I took for being a cube before was the plane being cut off by the frame extents and the background outside the frame matched the black within it; making it appear that it was a cube that had conflicting reflections and shadows.

djwaterman
02-11-2016, 06:08 PM
The cube and ground plane were just test objects from my scene that he included into his scene for comparison, so you can delete them. The bottom line is that I don't think there is any problem with his scene reflection-wise, it was just the dissolve curve needed tweaking to smooth out the dissolve and eliminate the pop.

Having said that, and having looked at the AVI, I think that the cleanest solution would be to render two versions and dissolve between both in post.

Deep_Thought
02-12-2016, 04:35 AM
Alright, I did some more testing and narrowed it down a bit. The culprit seems to be the reflection environment together with the bump map. I applied a Ripples texture to the plane's bump channel and added step by step all the values to match it with the logo's bump texture. The reflection of the dissolving object is always fine until I set the Reflection Options to Ray Tracing + Backdrop. Boom, jumpy shadow again.

I will do some more testing. There could be some issue with this particular reflection map (although I doubt it, it's the classic LW FractalReflections.iff) or the scaling of the map could be off.

I have to admit I really do not want to do any post-processing. This should be basic stuff that Lightwave takes care of smoothly anyway. Oh well, back to the drawing board...



Edit: Typos

MonroePoteet
02-13-2016, 08:28 AM
Can you post the full scene with images? The ZIP file previously doesn't contain the images you're using, and I can't find the one you referred to in the LW Content.

Thanks,
mTp

Deep_Thought
02-13-2016, 04:21 PM
Can you post the full scene with images? The ZIP file previously doesn't contain the images you're using, and I can't find the one you referred to in the LW Content.

Here you go:

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I played around some more and changed djwaterman's scene again. No more need for my objects with lots of points. I colored the cube green and added a blue back wall to get a better grip on the dissolve effect's influence on the reflection. Render this scene with Reflection Options of the Ground Plane surface once set to Ray Tracing + Backdrop and once set to Ray Tracing + Spherical Map and compare the animations.

This is my take on the results:

When rendered with Ray Tracing + Backdrop everything is fine. The cube starts to fade in and its reflection in the ground plane does as well. Through some part of the cube's reflection we see the reflection of the blue back wall and through another we see just the black backdrop.

Let's enable Ray Tracing + Spherical Map. Again, the cube fades in smoothly. The part of the cube's reflection through which we can see the blue back wall behaves as before. At first the back wall is reflected clearly and then it is getting obscured more and more as the dissolve value of the cube approaches 0%.
The part of the cube's reflection that should show the spherical map (and did show the backdrop in the previous rendering) behaves wrong. We can clearly see that this area of the ground plane reflects a very bright part of the reflection map. But the part of the plane where the almost fully dissolved cube should be reflected shows a very dark reflection instead which is actually the backdrop.

I rendered frame 21 with both reflection options and compared the color values of the area where the cube outside the back wall is reflected. They are identical. It looks like the reflection map is not taken into account if a partly dissolved object is reflected. Correction: The reflection map is not taken into account if there is any object to reflect at all, because the reflection of the blue back wall stays the same regardless of the Reflection Options. This is consistent with the idea that a reflection map is some kind of outer sphere surrounding the scene. Therefore, a workaround could be to create such sphere as an object and not to use a reflection map at all. I will try that as well.

Edit: Ok, the sphere idea did not work. If the sphere is opaque, the reflection map will not be reflected at all. It the sphere is transparant, we are back to square one with the reflection map not being reflected through reflections of partly dissolved objects. Also, a transparent sphere roughly triples the rendering time.

I tried something else, though. I just put an envelope on the transparency channel of the cube instead of the dissolve channel. Guess what, it works perfectly and the reflection map can be seen cleary through the transparent reflection. It looks like Lightwave's object transparancy is finally good enough to be a suitable replacement for dissolve. I remember having difficulties with transparency back in the days of LW 6.

Right now, this is good enough for me. I still have to see how this turns out with my bigger scenes but it looks promising at the moment.

Thanks to all of you for your valuable input.

spherical
02-13-2016, 05:29 PM
Thanks for the complete scene. I'll see what I can learn. It's always good to learn.

FWIW, when your question was first posted, I wondered in the back of my mind why you were enveloping dissolve instead of transparency; but I didn't voice that question, instead tackling the problem using your method. Obviously, that didn't work. :)

djwaterman
02-13-2016, 08:58 PM
The reason one might want to do this in post is because with dissolve or transparency in Layout, the actual object geometry is dissolving, revealing that it has interior space. This is not usually the look you want when you want an object to fade up into view as a solid shape, you don't want to see the insides of the object during this process. So I'd still go for a post processing solution, actually all work should go through some form of post processing, especially logo type graphics.

spherical
02-13-2016, 10:32 PM
I did notice the inside of the CPU die showing first then being obscured by the outside when the dissolve reached 0. Thought it odd, but had no time to investigate. Thanks for supplying that.

Deep_Thought
02-14-2016, 05:52 AM
The reason one might want to do this in post is because with dissolve or transparency in Layout, the actual object geometry is dissolving, revealing that it has interior space.

Actually, that is a very good point which I did not consider yet. How would you go about that? What kind of software would you use?

MonroePoteet
02-14-2016, 08:55 AM
Definitely a bug in Spherical Map handling combined with Dissolve, at least on V11.6.3. Attached is a very simple scene. Go into VPR, step from Frame 0 to Frame 1, and note the profile of the reflection of Unit_Cube_1 popping into full reflection both in the Ball and in the Ground, even though the object itself is still dissolved over 99%. The code for applying the spherical map clearly doesn't consider the dissolve percentage of any object occluding the "globe" of the spherical reflection. The Texture on Unit_Cube_1 fades in at the same rate as the cube itself, but the occluded area of the Spherical Map immediately becomes opaque.

I don't know how you're going to get the reflections in a complex 3D object (e.g. the Logo) by having the object dissolve in post, but I'm no expert in compositing. I think a way of resolving the issue might be to add a Textured Environment backdrop with the spherical image mapped to the environment. It'll look gross in the initial render, but the environment isn't included in the Alpha channel, so you could composite it into an animation, even with LW by using the Foreground Image and Foreground Alpha on the resulting image sequence. The downside is that the environment will reflect in ALL reflective objects, not just the Logo.

Otherwise, I think you'll have to come up with a surface for the Logo that you like that doesn't use a Spherical Reflection Map in the Environment tab. Applying the same map to the Bump channel might work.

mTp

P.S. Applying the envelope to the Transparency channel rather than Dissolve doesn't work, because the cube has to be 0% dissolved for the Transparency to work, which occludes the Spherical Reflection globe.

djwaterman
02-14-2016, 10:46 AM
Actually, that is a very good point which I did not consider yet. How would you go about that? What kind of software would you use?

I use After Effects, but for free compositing apps that are more node based there is Natron ( a Nuke clone), Digital Fusion beta from Black Magic and Blender's built in nodal compositor.

http://natron.fr/

https://www.blackmagicdesign.com/au/products/fusion

http://www.blenderguru.com/tutorials/introduction-to-the-compositor/

djwaterman
02-14-2016, 10:55 AM
Definitely a bug in Spherical Map handling combined with Dissolve, at least on V11.6.3. Attached is a very simple scene. Go into VPR, step from Frame 0 to Frame 1, and note the profile of the reflection of Unit_Cube_1 popping into full reflection both in the Ball and in the Ground, even though the object itself is still dissolved over 99%.

Yes, in LW 11.6.3 this is the case, yet in 2015 it works fine. I tried your scene in both.

Deep_Thought
02-14-2016, 11:21 AM
Definitely a bug in Spherical Map handling combined with Dissolve, at least on V11.6.3. Attached is a very simple scene. Go into VPR, step from Frame 0 to Frame 1, and note the profile of the reflection of Unit_Cube_1 popping into full reflection both in the Ball and in the Ground, even though the object itself is still dissolved over 99%. [...]
P.S. Applying the envelope to the Transparency channel rather than Dissolve doesn't work, because the cube has to be 0% dissolved for the Transparency to work, which occludes the Spherical Reflection globe.

I took your scene and applied my transparency workaround. Could you try and render it and see if it works for you? For me it looks fine, with the cube's reflection smoothly fading in.

One thing to mention, though, is that if an object has more than 0% Reflection value, that Reflection value must also be envelopped to 0% as long as the object is 100% transparent. In your scene that was not necessary as the cube had 0% reflection value anyway.

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MonroePoteet
02-15-2016, 03:41 AM
Yes, an F9 render works fine in V11.6.3. But in VPR, the Spherical Map is still occluded by the cube 100% at frame 0 when the Transparency is 100%. I had only looked at the VPR presentation when I tried the Transparency solution.

Thanks,
mTp

spherical
02-15-2016, 04:16 PM
2015 VPR has a number of limitations, whether in Draft mode or not. These are reported to have been removed in LightWave Next and you'll get a VPR preview with all of the features of a full render.