goBIM is an iPhone, iPod, and iPad application for navigating 3D BIM models and their associated data.
Designer Ian Keough, a Senior Technical Designer with Buro Happold Consulting Engineers, in New York, independently developed the application to solve the problem of transferring 3D BIM models from the desktop to an accessible format for real-time review on the job site.
goBIM employs a two part process for designers to export their 3D model from their modeling application onto the iPhone. Users first export their 3D model into a “.gbm” file through a file exporter, then upload the files to their web server for use with goBIM. There is an exporter for Autodesk Revit available on the goBIM website
You can load the model through iTunes file sharing or post the file onto a web server and you have your models whenever, wherever you want them.
What size models can goBIM handle?
The size of model that goBIM can handle is dependent on three factors, number of triangles, number of parameters, and number of materials.
◦Triangles are the mesh faces that are pushed to the GPU and are used to calculate how your model looks on screen. More triangles = slower performance. Unfortunately, many BIM models have highly detailed components with lots of faces. Try and limit the complexity of your exported geometry.
◦Parameters are the fields that store information about the elements in your goBIM model. Each parameter name and value take up memory when your goBIM file is uncompressed.
◦Models with more materials affect performance. goBIM uses a batching methodology that groups together geometries with the same material before sending them through the graphics pipeline. This is referred to as a “draw call”. Less materials =less draw calls. Try to limit the number of materials that are used on your goBIM models.
The best advice that is to start with a small model, a few elements, to make sure that goBIM works for you. Then work your way up in model size until you reach the limits of acceptable performance.
For more information, visit the goBIM website