ANR-11-JS02-007 : National Research Agency young researcher programme. Accepted in June 2011
Implicit Models & Meshes
Committee SIMI 2, Basic research
42 month, beginning 25/02/2012, ending 25/08/2015
Loïc Barthe
IRIT-CNRS UMR 5505 - Université Paul Sabatier
118, Route de Narbonne
31062 Toulouse Cedex 9, France
0033 (0)5 6155 6312 -


We propose to study and develop simple to implement, intuitive and robust tools for modeling tridimensional objects in order to generalize to most people the access to the development and the use of modeling and animation software. A substantial impact on the general public is the access to both the expression via the creation and the animation of tridimensional virtual objects, and the free creation of real objects using, for instance, 3D printers. To reach our goal, we propose to lean on the natural properties of implicit surface representations and to tackle the scientific challenges that prevent their wider practical use. We also wish to demonstrate the strength of implicit representations when they are used in conjunction with standard mesh representations in applications such as deformations (skinning, visually plausible crushing) and collision detections.

Ce projet propose la définition et le développement d'outils simples et robustes pour la modélisation d'objets tridimensionnels. L'objectif à travers ces outils est de permettre une démocratisation des logiciels de modélisation et d'animation d'une part en simplifiant leur développement mais surtout en proposant une grande accessibilité et une utilisation simple pour la prise en main rapide de ces outils par tout public. L'impact au niveau du grand public est important aussi bien pour permettre l'expression via les objets tridimensionnels statiques et dynamiques que pour faciliter l'accés à des outils de fabrication comme les imprimantes 3D. Pour ce faire, nous proposons de nous appuyer sur les bonnes propriétés naturelles des représentations d'objets tridimensionnels par surfaces implicites et de résoudre les verrous scientifiques qui bloquent leur plus grande utilisation. Nous souhaitons aussi démontrer la puissance de cette représentation quand elle est utilisée en conjonction avec des représentations classiques par maillages dans des applications de "skinning" et de gestion des collisions avec des déformations comme l'écrasement.

Preliminary works introducing and supporting the project:

2010 O. Gourmel, A. Pajot, M. Paulin, L. Barthe and P. Poulin. "Fitted BVH for Fast Raytracing of Metaballs", Computer Graphics Forum, 29(2), proc. of EUROGRAPHICS, pages 281-288, 2010. [pdf] [video] [more] [vimeo]

2010 A. Bernhardt, L. Barthe, M-P. Cani and B. Wyvill. "Implicit Blending Revisited", Computer Graphics Forum, 29(2), proc. of EUROGRAPHICS, pages 367-376, 2010. [pdf] [video] [more] [vimeo]



First Name
Men month
Associate Professor
IRIT - Université de Toulouse - France
Researcher (CR1)
LaBRI - INRIA Bordeaux Sud-Ouest - France
LJK - INRIA Rhône-Alpes - Grenoble Universités - France
Funded by the ERC EXPRESSIVE, European Research council
Department of Computer Science - University of Victoria - Canada
PhD Student
IRIT - Université de Toulouse - France

Partners involved in the project

First Name
PhD Student
IRIT - Université de Toulouse - France
Department of Computer Science - University of Victoria - Canada
via the Natural Science and Engineering Research council, Canada
PhD Student

INRIA Rhône-Alpes - Grenoble Universités - France
via the ERC EXPRESSIVE, European Research council


Implicit Decals

This video illustrates the use of n-ary composition operators (here, contact and overlapping operators) for the interactive creation and editing of textures composed of repetitive patterns. This work is not directly in the IM&M project. It is however closely related as it is a first experience with controllable n-ary operators. This research has been published in Computer Graphics Forum 33(1), 2014.

Implicit Decals by Erwin de Groot et al.

Geometric Skinning corrected by Field-Functions

This video illustrates the use of field function compositions for improving the realism of skin deformations at joints when animating an articulated model with geometric skinning. This technique performs in real-time and introduces the concept of field function based mesh deformations, especially in the presence of contact. This research has been published at Siggraph 2013 (Transactions on Graphics 32(4)).

Implicit Skinning from Rodolphe Vaillant on Vimeo.

Gradient-Based Blending

This video illustrates how the composition of implicit surfaces using union, intersection, difference, blending and bulge-in-contact can be done in an effective manner by avoiding standard artefacts (blend at distance, unwanted bulge, etc). This theoretical research work has been published in Transactions on Graphics 2013 (32(2)).

by Olivier Gourmel. From Loic Barthe on Vimeo.

Animated VORTEX's Logo

Using the results presented in "A Gradient-Based Implicit Blend" by Gourmel et al (partially funded by IM&M), only five equations and a simple ray-tracer are required to produce this video. We use three field functions of R3 in R for representing the ground, the logos sheres and removed extruded object. We also use two operators of R2 in R: one clean union/difference operator for the construction of the logo and one bulge-in-contact operator to handle its deformation when it comes in contact with the ground. All contact deformations are thus automatically generated. In this animation, no collision test and no mesh is used.

by Olivier Gourmel. From Loic Barthe on Vimeo.




2014 E. de Groot, B. Wyvill, L. Barthe, A. Nasri and P. Lalonde. "Implicit Decals: Interactive Editing of Repetitive Patterns on Surfaces", Computer Graphics Forum, 33(1), pages 141-151, 2014. [pdf] [video] [vimeo]

2013 F. Canezin, G. Guennebaud and L. Barthe. "Adequate Inner Bound for Geometric Modeling with Compact Field Functions", Computer & Graphics, 37(6), proc. of SMI, pages 565-573, 2013. [pdf]

2013 R. Vaillant, L. Barthe, G. Guennebaud, M.P. Cani, D. Rhomer, B. Wyvill, O. Gourmel and M. Paulin. "Implicit Skinning: Real-Time Skin Deformation with Contact Modeling", ACM Transactions on Graphics, 32(4), proc. of ACM SIGGRAPH, 2013. [pdf] [video] [vimeo] [YouTube] [transfer] [free codes] [more]

2013 O.Gourmel, L. Barthe, M.P. Cani, B. Wyvill, A. Bernhardt, M. Paulin and H. Grasberger. "A Gradient-Based Implicit Blend", ACM Transactions on Graphics, 32(2), presented at SIGGRAPH in July 2013. [pdf] [video] [vimeo] [free codes]

En français

2012 R. Vaillant, L. Barthe, G. Guennebaud, M.P. Cani, D. Rhomer and B. Wyvill. "Déformation de la peau d'un personnage avec prise en compte des contacts", Revue Electronique Francophone d'Informatique Graphique, Prix du Meilleur Papier AFIG/EGFR.



  • CNRS Activity Report 2013: Researches on Implicit Skinning are presented in the CNRS Activity Report 2013 (page 46).

  • Mediation with large public: The use of implicit surfaces in geometric modeling or skinning applications serves as support for the attractive illustration of mathematics learned at different levels of education. All informations here.



  • Latest advances in Implicit Skinning: We develop products in order to insert the most advanced version of our skinning technique in your professional animation software or animation pipeline. We also provide expertise and support. All informations here

  • Implicit Skinning (Siggraph 2013): Our codes implementing the implicit skinning technique are available under academic only license. All informations here.

  • IBL: Our binary composition operators for 3D scalar functions are implemented in the Implicit Blending Library. It is accessible under academic only license. All informations here.