2D Low-poly illustration from 3D scene

2D Low-poly illustration

I like the feel of 2D low-poly illustrations. Here is some examples.

low-poly-illustration-photoshop-tutorials-5 low-poly-OlbS8f2 Low-Poly-2D-experiments-6

 

 

The process to create this kind of illustrations can be tedious, as described in this tutorial.

Given a reference image, the artist has to :

  1. Draw triangles, following hard lines of the initial image, creating small triangles on detailed zones and bigger triangles on coarse zones
  2. Create each triangle with Illustrator
  3. Snap together points from neighbors triangles
  4. Color each triangle

Some WIP from the illustration I created following those steps.

low-poly-falcon-wip-1 low-poly-falcon-wip-2 low-poly-falcon-wip-3 low-poly-falcon-wip-4

And my result :

cpt-falcon3-with-arm

It does look good, but it took me 20-30 hours. So I thought of an automatic tool producing this kind of result.

 

From 3D scene to 2D illustration

I present here my ideas to implement such a tool, still under construction !

Projective approach

I would like to produce this kind of illustration from a 3D scene. .

So, given an arbitrary 3D scene (ie high or low poly) and a point of view, the process would be :

  1. Simplify the scene to keep a small number of triangles
  2. Project the 3D scene on the 2D projective space of the point of view
  3. Pick colors from the scene for triangles

I also want to keep this editable on Illustrator (to change some colors for instance), then the output will be vector triangle (eventually a SVG file).

But an obvious drawback of this approach will be the look of the result. The triangles are seen from a point of view, and we can’t get rid of the feel of perspective. It will eventually still look 3D, like those flat shaded rendered scenes. You can get a good feeling of this comparing r/lowpoly2d and r/lowpoly.

Blender_LP_Illustration_Preview MdCWeiC

And that is not what I want to get.

 

Constrained Delaunay approach

To get rid of the perspective look, we have to work in the 2D space.

I think about using a Delaunay triangulation on 2D point (projections of the 3D points). It would produce regular, noce lloking triangles.

A constrained Delaunay triangulation could be used to preserve hard lines of the scene and can give so control if the user would be able to input those lines.