Export Best Practices
What file types and export settings to use for different workflows
Last updated on June 21, 2022
Gravity Sketch allows you to export to 3 different file types, each with a set of options. This article will walk you through the various file types and how to use them. When Exporting your data from Gravity Sketch VR, you can choose to export to the OBJ, FBX and IGES file formats. Choosing which format to export to depends on your workflow and how you will be using the file once exported. In this article we will breakdown which file types you should export to depending on your workflow. For each workflow we will list the file types that can be used as well as the recommended settings for that workflow starting with Mesh Type, what data to export, and what normals setting to use. Before we list the various settings to be used, lets quickly take a look at the 3 different formats you can export rom Gravity Sketch VR:
The OBJ File Format
The OBJ file format is widely compatible with other polygon modeling software programs. An exported OBJ contains geometry information, color information, and normals information and is a relatively simple file format as it is one of the oldest interchange file formats around. OBJ files do not contain layer information and when imported, come in as a single object with material groups. It’s important to be aware of this limitation when exporting to OBJ, as editing can be more complicated. OBJ files can be a good option for relatively simple files, or for creating quick renders. OBJ files work well with Autodesk Alias, Maya, Blender and Keyshot. They do not work with Solidworks.
The FBX File Format
The FBX file format gives you several unique options, and is widely compatible with many workflows and other software programs. The FBX file format is essentially a modernized version of the OBJ format that can contain more information about your model. In addition to containing geometry information, color information, and normals information, the FBX file can also contain layer information, part information, and camera information. This can enable more efficient workflows. For example complex models can be edited with ease in other programs. And if you plan on rendering, you can set up the cameras inside Gravity Sketch with viewports, and these same viewports carry over into other programs as cameras. In addition to this, FBX files can also contain NURBS data too in the event you have a mixed file format. In the advanced settings, you have the option to choose between Mesh, NURBS plus Mesh, and Full Data. Mesh will convert everything to mesh geometry. NURBS+ will retain any NURBS data, and export that alongside any Mesh data. Full Data will export everything in the model, but goes one step further. With full data, you will get both the Render Mesh and the control mesh in the same file, and everything is neatly organized in a set of easy-to-use layers. This is a great option for more advanced workflows where having components of both the render mesh, and control mesh could be useful to have. FBX files work well with Rhino, Blender, Maya and Keyshot. They do not work well with Alias or Solidworks.
The IGES File Format
The IGES file format is primarily used for exporting NURBS Geometry. Since you can create both NURBS curves and NURBS surfaces in Gravity Sketch, using the IGES File format is a good option if you want to continue working in other NURBS based software applications such as Alias, Maya or Rhino. It is important to note that any polygon data will be converted into NURBS patches, which can make it tricky to edit later on. NURBS data on the other hand exports like for like. Any strokes or curves created in Gravity Sketch are converted to NURBS curves however, and do not have any kind of dimension. There are no advanced options for the IGES file format as the format itself pretty much packages NURBS data into a well recognized interchange format. IGES files work well with Rhino, Maya, Alias, Keyshot and Solidworks. IGES files do not work well with Blender or other poly-modeling software programs.
Workflows
The following information indicates what formats to use depending on the workflow and end result.
Exporting for Photorealistic Rendering
For example programs like Keyshot, Blender rendering, VRED and Substance Painter
Export for Rendering in Game Engine
For example Unity and Unreal engine
Exporting for Factory Communication
For example sending models to factories to prototype.
Exporting for Model Continuation
For example Blender, Rhino, Alias SubD Modeling: FBX (Recommended) - Control Mesh
OBJ - Export two (2) versions - 1 control mesh file, and 1 render mesh file.
NURBS Modeling:
IGES (Recommended)
Exporting curves Only
Useful for building curve networks or guides to build surfaces in other programs such as Rhino or Alias.
Exporting for 3D Printing
If going directly to printing, be sure to ensure that all surfaces are closed, and all points are welded in Gravity Sketch. Also be sure to ensure that any thin surfaces have thickness, and are not simply a surface.
UV Unwrapping
For Texturing and adding materials.