How can you optimize 3D model file sizes?

Consider implementing procedural generation techniques, especially for natural elements like terrain, foliage, or clouds. Procedural generation can create complex details algorithmically during runtime, reducing the need for high LOD in the base model.

With organics you can have a low resolution mesh and influence it with topographic UV. This allows you to be easier on less modern graphics hardware or integrated graphics. This method works on OpenGL as well. The issue with LOD switching is that you now hold multiple assets in your graphical memory. Iterating over thousands of models 4 times in one complex scene is not ideal. You can use one high res texture set and downscale the resolution instead. Your meshes will end up being 128 vertices and look exactly the same. Another thing to look into is using splines instead of vertices. Depending on your program, you should be able to convert it to spline. It draws a curved ray across a fixed path and is more natural looking without edges.

Additionally, letting the computer generate details for things like landscapes helps keep files smaller. Using one high-resolution texture smartly and considering splines over vertices further contributes to an optimized 3D model.

LOD switching: Implement LOD switching by creating multiple versions of your model at different levels of detail. Switch between these versions based on the object's distance from the viewer or printer. Objects that are farther away may require a lower level of detail to optimize printing time and resource consumption.

Something is been useful for me, it's to work animation and dynamic simulations with a low-res version of the objects and then transfer these animation's attributes to the original models. This way, it's easy to iterate and adjust faster. I also think it's important to evaluate camera proximity and don't use hi-res models when they're far from the camera.

Simplicity is the most sophisticated design... You first of all want to check if you must import or rather use a preset basic color material available in the software... Because oftentimes you'll realise there isn't much of a difference especially if the detail is out of the camera focus. Pay attention to what matters, and what shows is what matters :)

Utilize advanced texture streaming techniques where high-resolution textures are loaded dynamically as needed based on the camera's proximity to the object. This approach can significantly reduce the initial load on the file size without compromising the visual quality.

Pack your texture channels. Do not use one black and white image for roughness, one black and white image for metallic.... Utilize every RGBA channel in your textures. For normal maps you can skip one channel, as it can be recalculated from the other two channels, and put another data texture in it. If you are going for a really low poly target art style, or really far away model you can maybe skip textures and only use vertex colors.

???Navigate the fine line between quality and file size by addressing texture resolution. Scaling, cropping, and baking are your allies, reducing image size while preserving visual impact. ??Embrace texture atlases to consolidate multiple textures into one, mapping them strategically across your model for a cohesive appearance.

Knowing the actual final resolution expected for the viewer is important. If your final screen size is 1920x1080, and the uv island of the asset, more or less, takes up half of the screen then there is no benefit to generate a texture greater than 1000px x 1000px as the viewable texture will only ever utilise 1000px on the screen anyway

3MF is the preferred format for additive manufacturing/3D printing with the mesh representation typically 1/3 the size of an STL and the beam extension making it possible to communicate complex lattice structures in orders of magnitude smaller than any other file type.

Explore the use of modern, efficient file formats like USDZ or Draco, which are designed for quick rendering and small file sizes. These formats are increasingly supported in various 3D graphics applications and can offer optimizations for both storage and performance.

Hoy dia se utilizan todo tipo de formatos, por lo que "elegir" es algo que cambiará según las necesidades. Se está discutiendo mucho el uso del formato "USD", el cual sirve como un formato universal el cual puede funcionar en gran parte de los softwares 3D, ya que se creó con ese cometido.

Most game engines are primarily built for .fbx and .obj. They tend to come with metadata so they can be packaged as one with their materials, saving developers time at the cost of memory. Make sure the tools you're using are compatible with the format of the mesh you're making.

Your printer will have a prefered file format. While gcode is the simplest format, others like AMF can carry more data for optimal performance and print quality.

Para comprimir un modelo 3D, se pueden emplear métodos como la reducción de polígonos para simplificar la geometría, la optimización de texturas y la eliminación de datos redundantes o innecesarios. La conversión a formatos de archivo más compactos y eficientes, como glTF, ayuda a reducir el tama?o. Además, la compresión de archivos estándar como ZIP y técnicas de streaming o niveles de detalle para aplicaciones en tiempo real también contribuyen a minimizar el tama?o del modelo. La combinación de estos métodos garantiza una compresión efectiva sin comprometer demasiado la calidad visual.

Blender has a feature known as 'decimate modifier' using which you can reduce the number of vertex points on a highly dense mesh. Which will change the topology of the mesh. Then using 'Remesh modifier' we can optimize the topology. This is the technique I use in blender for example when I want to create an animation which involves 3D model of protein. Usually they are very dense. Which will greatly reduce the file size.

Revit files inherently incorporate compression methods to maintain data integrity. When sharing models, consider using tools within Revit for file compression, facilitating smoother collaboration without compromising essential data.

Most users use the compression tool available in their CAD package, which tends to lead to considerable limitation of solutions. The prior simplification of the model, and the execution of some sequences of format changes end up being the tool used by many.

1. **Remove Hidden Geometry:** Eliminate geometry that is not visible in the final render, such as interior faces or components that are not seen by the camera. 2. **Optimize Animation Data:** If your model includes animations, optimize animation data by removing unnecessary keyframes and refining motion curves. Always keep in mind the balance between file size reduction and maintaining the required level of detail for your specific use case.

Simplify geometry by reducing unnecessary details without compromising essential features. Utilize efficient mesh structures and consider using level-of-detail techniques to adjust complexity based on viewing distance. Choose appropriate file formats and implement effective data culling to remove unnecessary elements, ensuring a balance between visual quality and optimized file size.

The Test and Iterate involves regularly checking the impact of changes on file size while preserving visual quality. It necessitates a balance between reducing size and maintaining crucial details. This iterative process includes assessing each optimization's effect on file size, ensuring visual fidelity remains intact. Testing within the intended software or game engine confirms compatibility and performance, while comparing optimized models against originals helps validate improvements. Documentation of changes and revisions based on testing outcomes ensure an efficient, visually appealing final product.

- Before start 3D modeling make sure of what is exactling required to get from the model. - You have to model the amount of data only required to your stage (LOD100 for Concept, LOD200 for Schatic, LOD 300 for Detailed Design, LOD400 for Comstruction Document,....) - Normally make each system in a separate model (Arch, Str, Mech, Elec, Plumbing). This is better for model size, performance & user permissions. - Even after making separate model for each system, you may need yo split the model of a specific system into separate models if the project scale is huge (ex: High rise building) - Donot insert CAD drawings into your model or at least minimize the number (use link instead of insert). There are more but the text limitation here ??

In my experience , using xrefs and proxys for compicated mesh is the right way to reduce file size and make it smooth to handle .

For a 3d model optimization we can take various actions like mesh cleanup, retopology, reduce polygons, remesh, decimation, deleting history, namespaces, removing unknown nodes, etc.