About Me


Hi everyone! I’m currently a 3rd year PhD student at Inria Sophia-Antipolis, in the beautiful south of France. My PhD supervisor is Adrien Bousseau and we are working together on sketch-based modeling. Aside from that I’m very interested in discrete optimization, computational design and more generally in approaches which tackle mixed-integer problems.

Outside of work I like to do slacklining, bouldering and reading novels.

If you want to contact me, please do so by mail: felix.hahnlein@inria.fr


Symmetry-driven 3D Reconstruction from Concept Sketches

Felix Hähnlein, Yulia Gryaditskaya, Alla Sheffer, Adrien Bousseau
SIGGRAPH North America 2022

In this project, we investigated how to use symmetry to reconstruct concept
On the one hand, finding out which strokes are symmetric with each
other and how to position symmetry planes is a challenging problem.
On the other hand, symmetry allows us to pre-compute all 3D stroke
candidates and to use an integer programming formulation to solve a
difficult combinatorial problem.


Lifting Freehand Concept Sketches into 3D

Yulia Gryaditskaya, Felix Hähnlein, Chenxi Liu, Alla Sheffer, Adrien Bousseau
SIGGRAPH Asia 2020

In this project, we lift design sketches into 3D.
Assigning depth to 2D strokes is a highly non-convex problem, which we
tackle by solving a discrete proxy problem: deciding whether or not a
2D intersection is an occlusion or an actual 3D intersection.
Observations from design practices allow us to formulate an objective
function for this optimization problem.


Bitmap or Vector? A study on sketch representations for deep stroke segmentation

Felix Hähnlein, Yulia Gryaditskaya, Adrien Bousseau
Journées Françaises d'Informatique Graphique 2019

In this short paper, we investigated sketch segmentation performance
differences when processing the drawing in two different input
formats: (i) as pixels and (ii) as point clouds.