Inventor - Improve Render Times By Preparing Your Model

By David Gate

How to speed up your rendering in Inventor, Showcase or 3DS Max by preparing your model correctly.

The Autodesk Suites come with a number of visualisation (visualization) tools. Inventor has some built in render tools, but you can up the quality of your render by using Showcase or even more with 3DS Max. 

One thing with visualisations are that to create nice photo realistic images can take some time, but you can reduce the render time by preparing your model in the correct way.

It is most likely that your Inventor model is highly detailed with full manufacturing details. A lot of this detail is not actually required for the visualisation.

A good example is Nuts, Bolts, Washer and their respective holes. I.e. if you have a bolt going into a hole like below.

In truth the model has too much complexity for visualisation purposes because it has all the detail of the hole and the bolt size inside.

If we import the model as is, Showcase will be trying to work out if light gets between the bolt and the block, and then potentially down the hole. Other often troublesome geometry where 2 bodies intersect can also mean excessive complexity.

Thankfully Inventor has a very useful tool that will remove model complexity but retain the outer appearance (the critical part when creating visualisations). It is called Shrinkwrap.

Now take a look at the resulting model after shrinkwrap. You might want to play around with the settings but here are the basic ones I used.

From the outside it looks exactly the same.

But the section is very different.

A comparison in Showcase shows there is a 65% reduction in the complexity of the geometry without effecting the visual integrity of the render.

Now the impact of this on the render is not unfortunately 65% quicker as the model is still very simple. There was only a 4% improvement in this case, but this is just 1 component into 1 other, imagine this being 100’s of components then that 4% saving adds up.

Below are 2 identical “Advanced Lighting” renders done quickly to Level 3 in Showcase. The first is of the full 300 part assembly. The second is of the shrink-wrapped part. We first got a 58% reduction on model complexity, meaning manipulating the scene, materials etc in Showcase was a friendlier experience, but the important bit is the 35% reduction in render time.

One thing to be aware of is that this is great for static images but if you are wanting to do any fancy animations or visibility/positional alternatives this unfortunately you can’t as it is now a solid lump.