This article provides tips and tricks to produce lightweight Collada files with Esko Studio software. If you have to produce 3D models for virtual store simulations, then these tips and tricks will help you make those virtual models that don’t impose too much load on the software and hardware. That can be important, as store simulation software needs to render many different 3D models. And typically also many copies of each 3D models. If the model requires too much system resources, this affects the performance of the store simulation.
We will focus only on Esko Studio software and we assume that you are already familiar with Esko Studio to make flexible packaging models and folding carton models, both with and without artwork.
There are two aspects to lightweight 3D models: Lightweight geometry and lightweight textures.
In 3D software, textures are used to add color, materials, print and print effects. These textures are stored in the Collada file as images. There are different textures for color, gloss, transparency, relief etc,. To render a 3D scene with many models, all texture images of all these models need to fit in the Video Memory. So if you need to render many different models in a 3D scene, you have to make sure that your models don’t have too many textures and that these textures are not too high in resolution. To inspect the textures in a .zae Collada file, just unzip that file. You’ll find one or more .png images.
To render a 3D object, it’s shape has to be described in polygons (facets). The more facets you use, the finer geometric detail you can model. But it comes at the cost of performance. So, for a lightweight model, we want to limit the number of facets.
You cannot expect a model with a low facet count to look as nice as the one with more facets. But when lightweight is a requirement, this is a compromise you have to make.
Studio does not give direct feedback about the number of facets. So, here is a trick to check the facet count of your models: Adobe® Reader® has a wireframe mode that allows you to see the facet edges. So, to get an indicative feeling of the number of facets in a shape, you can use Studio Designer to make a 3D PDF and view that in Adobe® Reader®.
In this example, you see two 3D models of a pouch. The one on the left uses very little facets. The one on the right has many fine facets, probably 20 times more than the model on the left.
Toolkit for Flexibles
When making flexible packaging models in this toolkit, you have to take precautions to limit the number of facets. If the .bag file has too many facets, then the resulting .zae file will do too.
Toolkit for Flexibles uses a mesh of triangles to simulate the behavior of the film. But these are not the facets that are rendered on screen: each mesh triangle can be divided into potentially dozens of facets. The Toolkit will do this subdividing mostly around ‘crispy points’. The main strategy for making a low-poly-count flexible model is to avoid crispy points. It takes a bit of practice to spot these crispy points. You should spin the model around and see how the highlights behave. The crispy points are fixed points on the flexible bag where the highlights tend to converge into. The image below shows a bag with a crispy point near its top left corner.
Main Trick: Set Rounding to Maximum
The quickest and easiest way to reduce facets in a flexible model is to set the rounding slider to its maximum value (1.00) in the Shape panel. This will drastically reduce the number of ‘crispy’ points. It’s these crispy points that require many facets.
Extra Trick: Refining the Mesh Locally
Even with maximum Rounding, there will still be some crispy points. If you really want to go for ultra-lightweight, then you can rid of a few more crispy points by making the mesh a bit finer in that area. That sounds like a contradiction, but if that gets rids of a crispy point, the total number of polygons will go down:
Left: A crispy point near the top-left corner. Middle: With the mesh tool, we make the mesh a bit finer in that area. Right: And after some live shaping, the crispy point is no more.
Toolkit for Boxes and Toolkit for Labels
There are no special precautions to take in these toolkits.
Toolkit for Shrink Sleeves
The 3D models made by this toolkit, tend to have many facets. These tips might somewhat reduce the facet count:
Mind the imported Shape
In this toolkit, you always start with importing a 3D file. All the facets of this 3D file will also end up in the eventual Collada file. So, make sure to start from a lightweight 3D file.
Set Accuracy to low
In the toolkit’s Preferences, set accuracy to low. That will reduce the facet count of the sleeve (if you also need to do artwork pre-distortion, then you should probably make two versions of your Collada file).
Visualizer was designed for advanced print modeling: combining paper texture, print, finishing effects etc,. To render the result, Visualizer requires many different textures. Hence the Collada files from Visualizer have many textures.
Make your Collada files with Designer, not with Visualizer
If you don’t need transparency or special finishing (or your rendering tool doesn’t support it), then you can save a lot of Video Memory by exporting Collada by Studio Designer instead of Studio Visualizer.
Switch off “Show board Thickness”
When your shape is a closed box, you can reduce the facets by a factor of 3 by deactivating Show Board Thickness in the Studio Designer Appearance dialog.
In Studio Designer, when you export to Collada, you can choose the artwork resolution. Exporting at a high resolution will create more and larger texture images. If you are asked to supply lightweight models, then you should output at a low resolution. A simple trick to limit the resolution in Studio Designer versions before 23.03, is to simply switch on the Include printable parts option. This will automatically adapt the resolution for every printable part so that its texture does not exceed one megapixel. In Studio 23.03 and later, this happens automatically.