Trouble rendering in Inventor 2021

[kristian]

Hello all

I'm trying to render a glazed structure however I'm coming up against 2 problems.

• The first is that when I try to render the shadows are not appearing in my renders.
• The second is that glass is not rendering in my images.

With regard to the second point, I have tried the following:

• Initially I modelled the glass using my own glass template. I set the material as glass, appearance as clear-light, and added as new solid bodies within the part spacer bars, silicone etc with their own appearances. These resulted in dark grainy renders with little transparency.
• Secondly, I went to make component for a number of these panes (you'll see these in white in one of the images) to convert the multibody parts into assemblies, with each body converted to a part. I also set the glass appearance for the glass part (now single body) as clear (not clear - light). This resulted in the solid white rendered panes you can see in the attached.
• I then modelled a new glass pane as a solid part template (not my glass one). I set the material as glass and made no other adjustments. I threw this into my assembly in front of the glazed structure (highlighted in blue in one image below) to gauge the transparency. This has not rendered well either - I even rendered this pane on its own and the render is poor (and also missing the shadow).
• These are with 32 iterations for rendering. I tried higher iterations with no discernible improvement.

I've provided some screen grabs of what is in the model window at the time.

Any help anyone can provide would be greatly appreciated.

[kristian]

Just to add I've tried all sorts of other ways of doing this. One attempt involved ray tracing this which almost worked, but all of the internal glass panes and fins are opaque black! Is there a way around this? I tried it on another project and in the Inventor Studio the render did the same. It seems to be this or have grainy glass which looks dark and frosted and never transparent enough (the one below was Gaussian 2.0 with 1200 iterations).

Could someone please offer a suitable workflow for creating glass parts within assemblies that can then be rendered?

Many thanks in advance.

[-niels-]

With the ray-tracing, did you set it to "low" or "draft" quality?
What happens if you set it to "high" and let it render until it reaches a satisfactory quality?

I made a quick test, created a few panes and applied a newly created color "solid glass"

Here's the difference between raytracing on draft or high:

I only let it run for 3 minutes, rendering glass is pretty intensive and can take a while depending on how much refraction/transmission it has to calculate...

[kristian]

Hello Niels

Thanks for your reply. I did them using draft for ray tracing. I set the material for these as glass, then the appearance as clear-light. I'm a little surprised that in mine at draft the second pane (the far end one with only one pane to obscure it) was pitch black. Did you change any of the appearance properties (e.g. refraction).

I'm trying ray tracing at high and as you say it is taking an eternity. Do you have any idea a structure like the ones below would take? When rendering in the studio do I need to allow an hour to render? 

I'm minded to use ray tracing and then export an image at present as I cannot get the shadows to work in the studio - the preview shadows don't appear in the render.

[kristian]

This was another go with ray tracing on high. The process 'completed' by itself after just 227 sec and it's no different from trying to render it in studio as per the earlier attempt.

I also note that there are shadows in this at the front of the glass box (e.g. door frame cast forwards when I've set them to go inwards) that are not in the viewport - it just seems to ignore my lighting settings.

As a renderer I'm finding Inventor infuriating.

[-niels-]

@kristian Sorry, i can't give any estimate on how long your renders would take.

It's pretty system dependent and your structures seem pretty large with lots of glass panes, so yeah... eternity feels right...

As i showed on my first screenshot; i created a new appearance from the dropdown called "solid glass".

This differs from "clear - light", just compare their options when editing them, though i'm not sure how it effects ray tracing / rendering.

The shadows are pulled from the lighting environment, the preview is NOT representative of what you get when actually ray-tracing.

So try putting ray-tracing on high with a simple object and check how the shadows fall for the different lighting scenes to pick one that gives you the shadows you'd like.

As for your frustration... i can imagine that a little.

I've never really rendered with Inventor after learning how to render with 3DS Max, i only do an occasional ray trace for a quick image.

If i need anything realistic i go to Max, a lot of people use different software for their renders when they want something more real.

I use 3DS Max, since it's part of the collection we have but there's also MODO, Keyshot, Vred, Blender, etc...

Most of those programs have a steep learning curve to set things up, but the end results are often worth it.

But, i've also seen some people post renders done in Inventor (studio) that look really good.

There's just a lot of time to invest to get all the materials, scene and lighting set up correctly.

[kristian]

Hello Niels

Thanks for the advice it's much appreciated. I don't think we need a renderer quite so specialist, this would be fine if the glass rendered properly, which it seems to for some people some of the time but for me it isn't at all happening. The latest attempt was after ~90minutes and 600 iterations and was absolutely terrible. It's a pity as it is acceptable for all other materials.

The DGUs below were modelled as multi body solids this time, two panes 6 and 10mm thick. Inside the glass box there are triple laminated panes for the glazing supports 10mm thick (30 total) - Gaussian 5.0 anti-aliasing. I've seen far better results with sketchup and the various plug ins and don't understand why Inventor cannot do this? The geometry doesn't seem particularly complex. I'm sure there's something simple or the material / appearance isn't set up correctly but I haven't the foggiest.

[-niels-]

Any chance you can share one of your designs, for me and others to try?
It might be easier to diagnose if we can check how your materials are set up...
(or a simplified example with the materials and scene setup like you want/use)

And maybe, for the tech savvy on here, post your system specs (CPU especially) to have an indication what you're working with?

[kristian]

Hello Niels

Hopefully this should work - the model is a bit thrown together to test out the rendering of the glass. I tried reducing the thickness of all the glass to 1mm (not in the attached) but it didn't have any effect.

https://we.tl/t-yEIGSQRRYW

In terms of PC it's  16GB RAM plus GeForce GTX 1060 6GB, processor i7-87000CPU @ 3.20GHz - I'd have thought the spec of the PC was more than sufficient.

Thanks

[-niels-]

@kristian thanks for the files, here's a quick comparison i did between the "clear - light" and a newly created "solid glass"

(sorry about the weird cut away on the text, image was too large for the forum and had to crop which went wrong a bit...)

This was at 2 min of ray tracing on the "high" setting on my system.

So i think for the visual you're after, you'll need to change the material.

To improve the render time a bit, i think that lowering the reflectance will help quite a bit.

I've attached the 2 panes that i added the solid glass appearance to, maybe you can copy from those.

I did have a bit of an issue getting them to update in the assembly, i had to make the representation "associative" so they reflected the actual part. (not worked with 2021 yet, just have it on my system for testing purposes...)

Hope this helps, let me know the result on your end.

Your system should be fine btw, mine is a bit newer so rendering is probably a bit faster.

(read: don't take the 2 min raytrace time as a comparison)

[kristian]

Hello Niels

Thanks for this. I lowered the reflectance and also reduced the refraction and this was the result after 9(!) hours of rendering.

It is still grainy and for some reason the silicone smears to the glass steps (modelled as 0.01mm thick solid bodies - appearance smooth -medium grey) looked scratchy and bizarre.

I think I'll have a play with the appearance settings but is there a limit after which iterations have no effect?

Appreciate your help on this.

[-niels-]

Wow, 9 hours... i commend your patience... (hope you did that overnight)

The bleeding / scratchy & bizarre you're seeing is probably because parts are touching (no clearance)
Did you change the appearance for all the glass? the sliding door and top windows don't look the same.
(asking because the "clear-light" might take longer to render)

As for iterations, not sure... like i mentioned earlier i only really use the ray-tracing and not studio.
I usually let that run until the bar is well into the green and the result looks OK...
You can let it run until "satisfactory", technically it will keep increasing the quality but you'll hit a point somewhere where we're not able to see the difference anymore.

[-niels-]

As i usually can't resist... here's a quick & dirty setup in 3DS Max.

Only made a few materials to apply to your model, so it looks quite weird, but this only took a couple of minutes to render (in the viewport even...).

[LishuangLu]

@kristian, 

Thanks for doing some rendering with Inventor ray tracing! 

It is a known limitation that the current ray tracing doesn't produce the expected result for some transparent appearances. This is caused by the old appearance defintion. To improve this, would you please have a try by adjusting the below two settings in your side? Eg. changing the Glossiness into a bigger value to reduce the noises, and changing the Transluency into a bigger value to make the appearance more transparent? 

Let me know whether it works for you. 

[kristian]

Hello Niels

Thanks again for trying with this - the finished render looks very high quality. We've now gotten 3DS max so will learn that to see if it can do the job. I note that the fins on your render are brick and on one view the glass to the sliding doors through the structure was black again - can 3DS max render that much glass as transparent?

Thanks

[kristian]

Hello Lishuang

I shall give it a go then report back.

[-niels-]

@kristian 

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@kristian wrote:

I note that the fins on your render are brick and on one view the glass to the sliding doors through the structure was black again - can 3DS max render that much glass as transparent?

---

Like i mentioned, i only applied a few materials... if every part was given it's appropriate material it would look much better.

As for the black glass in that last screenshot, i set Max to calculate for 8 layers (transmission, simplified it a a bit) but you can increase that amount depending on the depth you need.

(rotating the view like i did means i gained at least 1 extra layer, but probably would've needed to set it to 10)

Max will have no problems, it'll just take a bit more time to render.

Hope you have fun learning Max!

[lena.talkhina]

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@kristian wrote:

Hello Lishuang

I shall give it a go then report back.

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Hello @kristian !

I just read this thread and wonder what an amazing work you are doing.

I just wonder if you have any update for @LishuangLu ?

[jgjYRRKE]

Hi Kristian.

Just adding my opinion.

3DS Max is amazing for rendering, BUT....the learning curve is pretty steep and if you have many parts, then assigning materials takes forever.

I do a lot of rendering in Inventor 2020, but also find it very limiting.

Like max resolution for a rendered image is 4000x4000pixel in 2020.
Can you go higher in 2021?

Rendering with ground shadows is also very broken using Inventor studio.

Using Raytracing works with shadows, but then I cant get transparent background.

Basically, Inventor can be used to render, but is far from great.