Building a scene in Lumion is a simple and fun process that involves sculpting your landscape, setting the weather conditions, applying materials and placing objects. Objects like trees, people, buildings and cars are crucial in bringing your scene to life and often, the more the better, especially in larger urban settings. A lot of software packages struggle to handle large numbers of objects but this is an area in which Lumion excels.
The Pro edition of Lumion comes with a library containing around 3000 objects. These are not just any objects, they are all chosen and made (or fine-tuned) especially for Lumion. It’s also possible to import objects into Lumion from external sources.
This blog provides a brief technical background to explain why 3D objects should be chosen carefully, if they are not selected from Lumion’s own library.
Above: just a few of the 3000 or so objects in the Lumion Pro library
What is a 3D object?
Another name for ‘3D object’ is ‘3D model’ – these terms are often used interchangeably. A 3D object could be a house, a person, table, tree, plant, car or any other kind of object. Basically anything you see in your Lumion scene is a 3D object. All 3D objects are built up of ‘polygons’, which are usually triangular surfaces and each triangular polygon has three points (also known as vertices or 3D points), defining its location. Each polygon has information associated with it and places performance demands on your computer because each polygon needs to be rendered (processed) in real-time.
Polygons and Performance
The more polygons, the more demanding of your computer an object (model) is, and these demands can be huge. For example one tree can be made of 2,000 polygons or if it is inefficiently built, it could be over 250,000 polygons. More detailed objects tend to need more polygons but sometimes the polygon-count is unnecessarily high. Even one or two polygon-heavy objects can have a dramatic effect on computer performance. Similarly, objects have a color or are patterned and for this, a texture is needed. Textures can be created inefficiently or efficiently. Lumion works so fast, in part because all the objects in its library have been individually optimized to work efficiently in Lumion.
Above: The same object with three different polygon counts
Here are five tips to avoid problems with objects slowing down your computer:
- Use the objects in the Lumion object library as much as possible.
- If you import objects from anywhere else, it’s a good idea to check the number of polygons. For example, the SketchUp warehouse is a great source of free 3D content. The polygon count for each object is also clearly shown.
- When you prepare your model in your 3D modeling software, try to model efficiently and keep it neat and tidy if and when adjusted.
- When you import your design, if possible do not include unnecessary details. For example, excessive numbers of screws, nuts and bolts.
- If you want multiple copies of a model in Lumion, it’s better to import it once and then duplicate it in Lumion rather than import it multiple times into Lumion.
Lumion is very forigiving but these issues become more important when your computer has a limited specification, or if your scene is large or complex.
Luckily, the Lumion library is constantly developing with new models, hundreds of which continue to be included with every major release.
One last thought
It can be useful to think about your Lumion scene as a film set. Which props do you need to make it look right? Don’t put too many props in or placing them will be distracting and will take up your valuable time and computer resources. Too few will look incomplete. Think about the models that you want to draw attention to and which items are not so important. Above all, use models to make your animations and images absorbing and appealing to the people who will be seeing them.