BIMx: Notes on Model Data, 3D Model Settings, and Textures

These tips and technical details are intended for optimizing the Archicad model before saving it in BIMx.

The Archicad Model Unit preference (e.g. Imperial or Metric) will be used by default when the BIMx model is opened in a viewer application.

For a more detailed description plus examples, consult the article on “Archicad export optimization for BIMx” at this link.

Use Element ID Fields (For BIMx Hyper-models in Teamwork)

Each Archicad element has an Archicad ID, defined by default in its Tool Settings dialog box, under the Classification and Properties Panel. Make sure that your Archicad model elements include this Element ID data for best results in BIMx (if you are in a Teamwork environment).

Background: In a Teamwork context, BIMx provides smart feedback on multi-selection, identifying each element by its ID. If the Archicad model does not include this element ID data, BIMx cannot provide ID-based feedback on the selected elements.

Change in BIMx 3D format (Archicad 26 and later)

As of Archicad 26, BIMx models use a single, modern 3D model format.

In earlier versions, exporting to BIMx format required generating the 3D model twice - to accommodate two different formats (older and newer). The renewed mobile apps already use only the new 3D format. BIMx Desktop Viewer and BIMx Web Viewer products now also support the newer format and its benefits.

As of Archicad 26: The previous, outdated 3D model format is no longer exported, and all models are exported only with the newer format. Export from Archicad is considerably faster in many cases, and the file size is smaller.

Advantages of the new format are visible in BIMx Desktop Viewer and BIMx Web Viewer too:

BIMx model reflects Archicad Location Settings:

Direct light makes the model more realistic (north-facing sides are darkened). Set Project Location and/or North Angle in Project References > Location Settings to open the 3D model with the desired and realistic light direction in BIMx.

Automatic rotation of “Skybox” background

Archicad-defined View Cone is also reflected in BIMx. Define the desired View Cone in 3D Projection Settings. You can set different values for e.g. interior and exterior 3D models included in the same Hyper-model.

On-the-fly rendering (Ambient Occlusion) is available in BIMx Desktop Viewer and BIMx Web Viewer products as well as the mobile app. You can switch it on/off in these products’ 3D Settings

Textures

BIMx supports the following surface texture formats: jpg, bmp, tif, tga, png, gif.

If a texture would fail to load for any reason, the object that uses it will be drawn with the surface color instead.

As of Archicad 26, when exporting an Archicad model to BIMx, you can set your own texture size limit for a 3D view - for better control over texture quality, model size, and the time needed for export. The previous limit was hard-coded at 1024 pixels in Archicad 25 and earlier versions.

The new default is 2K, and you can max this out to 4K for best detail level, or choose a smaller texture size to limit file size and save time.

Alpha Channel Texture Effects

Use texture mapping and alpha-channel transparent pictures instead of physical models. This solution can be extremely useful if you do need a large number of trees, vehicles, fences and other complex objects in the model.

BIMx supports alpha channel texture effects with 32-bit tif, tga and bmp images. For the alpha channel effects to be detected inside BIMx, you must enable transparency in the Archicad surface/texture properties.

However, transparent objects are not necessary visualized using the correct display order - to do so would put a big dent in your performance.