Recently I created a complex LEGO model with Lego Digital Designer and wanted to import the resulting model into Blender. My export files were missing the LEGO Mindstorms EV3-components that I had added.
The reason for this behaviour are the missing parts in the ldraw.xml-File, which is in the same directory as the ldd.exe, the directory
C:\Program Files (x86)\LEGO Company\LEGO Digital Designer held this file for me.
The ldraw.xml is essentially a mapping file, which maps all the LEGO-internal structures to the more open „LDRAW“-File format. The EV3-parts weren’t listed and even in updated ldraw.xml-Files, which I could find on the web, these were never added.
So I created the missing mappings on my own and the result works pretty good. Not all the colours are correct, but I couldn’t find an easy way to correct these.
Here are the necessary steps to successfully export LEGO EV3-parts from Lego Digital Designer and import these with correct colours e.g. into Blender:
- Copy ldraw.xml file to your location of ldd.exe, overwrite the old ldraw.xml. (Unzip the ldraw.zip to ldraw.xml first)
- Export your model from Lego Digital Designer to „LDraw-Files (*.ldr)“-format.
- Open the file in notepad++, search for the following part numbers (they are located at the end of the line) and change the BEGINNING of the line from „1 71“ to „1 15“.
1 71 -90.175277709960937 -176.40634155273437 -275.99981689453125 0 1.0000001192092896 0 0 0 1.0000001192092896 1.0000001192092896 0 0 95658.dat
1 15 -90.175277709960937 -176.40634155273437 -275.99981689453125 0 1.0000001192092896 0 0 0 1.0000001192092896 1.0000001192092896 0 0 95658.dat
- Do this for all lines with these part numbers (not all might be in your file, only if you have added the corresponding EV3-bricks):
- Import the corrected file in LeoCAD and export into „Wavefront (.obj)“
- Open Blender and follow these instructions to get a first decent result:
- File -> Import -> Wavefront (.obj)
- Select -> Select all by Type -> Mesh
- Press „s“ (SCALE) and enter a value (blind, there is no dialog box), e.g. „0.1“ and hit return. Or you resize with your mouse after pressing „s“.
- Right-click and hold on the camera in blender, and move it around to where you want it to be.
- Check your current view by hitting the „0“ on your numpad. (This will change to the camera view)
- Right-Click during camera view on the border of the camera (it will turn orange), and then right-click and hold outside the camera view to tilt for your needs.
- Add some lights via Add -> Lamp -> Area (or Sun) and position them.
- Render by pressing F12
- In the render-menu on the right hand side you can change the size of the resulting image, e.g. „Preset: HDTV 1080p“.
- By pressing F3 the rendered image is stored to your disc. (Current used path is at the bottom of the render-menu, defaults to /tmp.)