How to create a low poly mesh

Something happened in the late 2000’s which made took us go from super high polygon counts to favor low polygon counts in models. I’m not sure if it was the yearning for the 90’s but these lo polygon models became quickly a hit. You can find a whole section in Thingiverse dedicated to high quality models exquisitely dubed down to low polygon models.

http://www.thingiverse.com/glitchpudding/collections/lowpolyholiday

I have to admit they do look really cool. I’m just guessing it’s the nostalgic beauty that’s talking back to us.

I was playing around with the Philae comets model availible from ESA  and I wanted to see how this would looks as a low polygon  model. I think this could be a great ornament for the Christmas tree. (http://blogs.esa.int/rosetta/2014/07/28/updated-comet-shape-model/)

To manipulate STL files I usually go to my favorite tool MeshLab. It’s an open source utility that’s incredibly helpful. If you haven’t already downloaded it get it here: http://meshlab.sourceforge.net/

Once you’ve loaded up meshlab it’s pretty straight forward to manipulate the mesh. STL or POLY files are made up of triangles that you can run reduce and manipulate using different models. For our little  comet we will need to reduce the number of vertices we have in the mesh.

To do this I’ve found the most useful method is Filters > Remeshing, Simplification, Reconstruction> Quadratic Edge Collapse Decimation.

lopoly12

Here you’ll find a number of variables. I’ve found that  most important to variables are Quality and Percentage reduction.

Percentage reductions is the amount of the vertices that should be kept. I use a number like 0.8 here and rerun the simplification multiple times. Each iteration will reduce 0.8 of the vertices.

Quality I’ve found difficult to decipher but using 0.5 had good result for me.

Preserve topology leave checked. (Helps keep the shape surface as is)

Preserve Normal leave checked.(Prevents flipping of surfaces)

Weighted simplification unchecked (This helps with a mor uniform simplification)

You should run the simplification algorithm multiple times. Unfortunately there is no undo function in meshlab so if things go too far you’ll have to start from the beginning.

loply3

If you wish to further manipulate the mesh in say solidworks you’ll have to export this mesh as a DFX file which solidworks can open as an object. Though granted you’ll have to do some healing

Make sure you export all surface when you export the mesh as DFX.

lopoly1

Now you can import the dfx file in solidworks or your 3d modeling program of choice.

Happy low poly holidays.

Alp

3D scanning in 15 minutes

Have a PC with a solid graphics card. Preferably something with CUDA or STREAM processors and Windows installed.

Intel’s HD onboard graphic cards will not do so well.

Get a Kinect. You can find one here -> www.craigslist.com, www.amazon.com, store.microsoft.com

Download the kinect for windows sdk here -> http://www.microsoft.com/en-us/kinectforwindowsdev/Downloads.aspx

After download the developer toolkit ->http://www.microsoft.com/en-us/download/details.aspx?id=40276

After installation plug in your and launch kinect “Developer Toolkit Browser”

Select “Kinect Fusion Explorer – WPF”  and you’re ready to scan.

Scan your object and export to STL or OBJ.

Download meshlab or another mesh editing tool of your choice to make the scan water tight. Open your model with meshlab. This part takes some practice but I’m not going to go into the grander details of it.

To make your model water tight. You can use Poisson mesh re-building or Delaunay mesh construction. Remove any floating pieces.

Load up stl file to printer app

Print.