Free SolidWorks .OBJ Exporter v2.0 published 1/4/2012 and all versions that follow:
This software is free for use and to distribute. It is NOT to be sold as is, nor in modified form,nor incorporated in other software for sale. This software and the accompanying files are provided as is. The macro will act upon the current SolidWorks document. As a precaution be sure you have a current back up your data before using this macro. There are no warranties, expressed or implied, that this macro will perform without fault. Use at your own risk.
The purpose of this macro is to export meshes in Alias|Wavefront .obj format from SolidWorks. The material's details are also exported as a standard Alias|Wavefront .mtl file. These may be subsequently loaded into Blender, Octane or other programs for rendering purposes. All files produced during export are placed in a new folder created in the same directory as the current document. eg D:\surfboard.sldpart --> D:\surfboard OBJ\surfboard.obj When you export again from the same SolidWorks document any existing OBJ directory and the contained files will be overwritten without warning. The macro UI provides the user with an opportunity to set custom tessellation parameters and other useful options. The macro should work as intended with SolidWorks version 2005 and up.
The SW macro can go anywhere but it is convenient to put it where you keep your other SW macros. You can use the provided toolbar button to launch the macro from SW. See the SW Help>Macros>customise buttons to find out how to set this up. See also the included picture of the custom button showing how to select the modSWtoOBJ.Main as the 'Method' to start.
The macro was originally authored in SW2009. Different SW versions may require you to open the macro in the SW MS VBA window, reselect the Reference Libraries appropriate to that version, and then save the macro. If this is the case, SW will show the References as being 'MISSING'. See the included 'References' picture of SW2009. Look down the list and find equivalent entries for the year of your SW install. Sometimes SW will find these references itself.
The macro should correctly traverse complex configuations and all forms of patterns correctly including exploded views. Assembly Features like holes and cuts are only considered if they are propogated to the parts. If your assembly has instances of the same subassembly or part but in different configurations it is necessary for the macro to force rebuilds as it progresses. This takes extra time and does leave open the possibility that some rebuild errors may be discovered in the model while that is underway. The macro will stop with an error, but no harm is done. You will however need to fix the issue in the problem part or assembly before you can successfully run the macro through entirely when re-running the macro again.
The tessellation from complex parts and assemblies is liable to take several minutes to complete particularly those with numerous configurations to traverse. The files can also be quite large. Be wary of tackling too much at once and creating a .obj that is too big to handle in other applications. Because the macro only exports visible objects you can break the mission down into convenient bites and then combine those .obj manually later in, say, Blender. The origin will be consistant across the files. It also means you can avoid having to redo the whole mission again if something changes.
You will find it hard to handle more than about 12m tris in any cg application presently. Such an .obj file out of this script would amount to something in the order of 2gb and take about 35 mins. A practical maximum size is probably 5 m tris. Note that 64 bit Windows is required for dealing with such large files. To give an idea of what a large model means the Mach5 model shown in some of the pictures is about 450,000 tris and the .obj is 87mb, so 11 of these would be enough. The number of tris produced isn't so much to do with the size or number of objects as the need to capture fine details with sufficient tessellation not to appear faceted.
You are not limited to the color textures supplied with SolidWorks. You can substitute others individually in the SW Appearances Property Manager or add a folder in the SW Task Pane for the usual drag and drop application. The exporter should find these and copy them to the same directory as the .obj at the end of the export process. You could also substitute other textures for the exported ones when the .obj has been loaded into another cg application.
You can nominate to export 'spec' and 'bump' maps(textures) on the basis of the color map (texture) used in SW. The requirement for this is that these need to have the same basic name and be in the same location as the color map(texture). For example - D:\myplace\mytexture.jpg, D:\myplace\mytexture spec.jpg, D:\myplace\mytexture bump.jpg
If you want to change the 'spec' and 'bump' labels to suit your own texture collection go to lines 592,593,596,597,605,611 in the vba module code.
If you nominate to use spec and/or bump maps in the UI the texture name will appear in the .mtl even if the images dont actually exist. The macro will skip any textures it cannot find. In the case of a missing texture Octane will prompt you for one as the .obj loads. Blender will load the file unhindered but you will need to source a substitute image afterward in the material's texture panel. In some later Sw versions some materials do have bump maps (of a sort) supplied, as well as the color map (texture).
You can set up a studio scene in a SW part and use that with your model. For example, it might include a floor/backdrop and rectangular surfaces to use as area lights. The part can either be inserted into your model part or used as a component in an assembly. You can use mates to position your studio or props exactly or just leave them floating. Of course you can use a number of parts for individual elements of your scene. See the included simple example of a studio made in SW09. Going through a cg app like Blender allows you to incorporate different props like trees or people that are hard to produce in SW and to reposition or duplicate them easily. You can also make use of other models like those of cars and trucks obtained from many sources and of different file types. The SW exporter does not handle mesh instances. Incidentally, the green side of a SW sketch plane is the direction of the normal.
The pictures accompanying this README show a mesh in Blender illustrating the standard SW tessellation and another where the max face length has been set to 0.15m. This control is handy to ensure the triangles are not too long and thin which is bad for use with render engines. With finer tessellation settings intricate shapes are reproduced well, particularly 3d curved surfaces, and it also allows for effective subdivision so normal maps can work effectively if applied later.
Smaller diameter parts need lower deviation settings to ensure that the tessellation presents sufficient roundness or smoothness when seen in a render. If you have an assembly that has both large and very small detailed parts use the SW Image Quality settings in each document rather than the custom settings in the macro UI - check the Disable option in the macro UI panel. Another way around this is to export just the large items in one .obj by making only them visible and then follow up with the smaller items in another .obj making only them visible, with custom settings for each as appropriate.
I suggest you try your export with the custom tessellation disabled in the first instance and if necessary use custom ones. The provided default custom numbers are a good starting point but will require some experimentation/familiarisation to get the best results in each case. To make sure very small parts are captured faithfully be sure to set the Max Chord Width small enough. Try 1/10th of the minimum radius of the smallest feature. You might need to set the Min Face Width to be almost as small if the objects are tiny.
SolidWorks is pretty poor at texture unwrapping. You will probably want to open the .obj in another application like Blender to tweak the unwrap and other aspects of materials. In the 'SW unwrap errors' folder included with this macro you can see examples of how poor the native unwrapping is. Even a stock std Blender Smart UV Project unwrap is a vast improvement.
The UV mapping styles in SW like spherical or cylindrical and the scaling, rotation, etc... do not actually make any difference to the unwrap that comes out of the SW API despite the change apparent in the 3d view looking at SW Realview. Do your alterations in other cg applications. If your model is mostly 'boxy' or prismatic and the texture has nondescript detail you may not notice poor unwraps too much in the render but in other cases the odd unwraps can be glaring or otherwise unsatisfactory. In simple cases you might get away with just changing the X & Y texture scale in Blender or Octane to suit rather than redo the unwrap.
There is an issue in SW2009 and probably later versions where the unwrap of cylindrical faces is especially bad. You can sort of fix this in Blender in the Texture>Image Mapping panel by using a Repeat of Y = 16x. It will still have other issues but this puts it back in the ballpark. This can be similarly fixed in Octane by scaling 16x in the textures Y axis.
---> All in all I suggest you redo anything other than basic texture mapping in Blender or another cg app if you want to end up with quality renders.
HAPPY RENDERING!! :)