Practical morphological antialiasing on the GPU

International audienceThe subject of antialiasing techniques has been actively explored for the past 40 years. The classical approach involves computing the average of multiple samples for each final sample. Graphics hardware vendors implement various refinements of these algorithms. Computing multiple samples (MSAA) can be very costly depending on the complexity of the shading, or in the case of raytracing. Moreover, image-space techniques like deferred shading are incompatible with hardware implementation of MSAA since the lighting stage is decorrelated from the geometry stage. A filter based approach called Morphological Antialiasing (MLAA) was recently introduced [2009]. This technique does not need multiple samples and can efficiently be implemented on CPU using vector instructions. However, this filter is not linear and requires deep branching and image-wise knowledge which can be very inefficient on graphics hardware. We introduce an efficient adaptation of the MLAA algorithm running flawlessly on medium range GPUs

Autonomous Lighting Agents in Photon Mapping

proceedings of ISVC'05International audienceIn computer graphics, global illumination algorithms such as photon mapping require to gather large volumes of data which can be heavily redundant.We propose both a new characterization of useful data and a new optimization method for the photon mapping algorithm using structures borrowed from Artificial Intelligence such as autonomous agents. Our autonomous lighting agents efficiently gather large amounts of useful data and are used to make decisions during rendering. It induces less photons being cast and shorter rendering times in both photon casting and rendering phase of the photon mapping algorithm which leads to an important decrease of memory occupation and slightly shorter rendering times for equal image quality

Morphological Antialiasing and Topological Reconstruction

International audienceMorphological antialiasing is a post-processing approach which does note require additional samples computation. This algorithm acts as a non-linear filter, ill-suited to massively parallel hardware architectures. We redesigned the initial method using multiple passes with, in particular, a new approach to line length computation. We also introduce in the method the notion of topological reconstruction to correct the weaknesses of postprocessing antialiasing techniques. Our method runs as a pure post-process filter providing full-image antialiasing at high framerates, competing with traditional MSAA

Autonomous lighting agents in global illumination

In computer graphics, physically-based global illumination algorithms such as photon-mapping have a linear progression between complexity and quality. To a given quality, rendering time scale linearly with computer performances. With Moore's law call in question and increasing demand in quality thoose algorithms need more and more optimisations. Existing optimisations such as irradiance caching are themselves very linear in performance gain. We propose a new optimisation method for the photon-mapping global illumination algorithm. We used structures borrowed from Artificial Intelligence such as autonomous agents to reduce computing time of the photon casting phase and rendering phase of the algorithm. Our structure called Autonomous Lighting Agents starts by using an agent-based scene discovery algorithm and is later used to make decisions during rendering inducing less photons beeing casted and smaller rendering times

From Research on the virtual reality installation

International audienceThis article presents a new virtual reality installation inspired by the CAVE system but non expensive (7000€) and transportable. Moreover, we especially focus on the feeling of presence. This means user should be able to feel his selfpresence in the virtual environment and the presence of the virtual objects and entities. Keeping in mind to increase the feeling of presence, we finally propose a dedicated game based on an immersive environment, consistent interactions and emotions

An OpenGL-Friendly Geometry File Format and its Maya Exporter

International audienceDespite being the lowest common denominator of CG applications, there is no de facto standard for geometry files. On the contrary, there is a plethora of both proprietary and open formats. One of the many reasons or this state of affairs is that each application has different requirements that are not efficiently compatible. An out-of-core path tracer will have different needs for its geometry-storing solution than a 3D editor or a game. Of course a kitchen-sink approach will offer all the needed features, but probably at the cost of computational and storage efficiency. The goal of this chapter is not to implement the ultimate geometry format. Instead, we will show how to tackle the problem by creating a file format suited to our needs along with the right tools. A file format is pointless without tools for exporting and importing but also for data-mining or conformation. Good tools enable rapid iterations on our asset production pipeline, thus increasing productivity and enabling better artistic impulse

A Virtual Reality Installation

International audienceThis article presents a virtual reality installation similar to a CAVE based system but less expensive and easily transportable. Like any virtual reality system else, our installation aims to immerse a user in a virtual environment. Hence, we especially focus on the userpsilas feeling of presence which means the user should be able to feel the presence of the virtual objects and his self-presence in the virtual environment. Thus, the installation must conform to the next four conditions: an immersive environment, interactions, to keep the coherence between the perception of the virtual world and the interactions and to propose an experience which generates emotions

Game Development Tool Essentials

XIX, 220 p. 84 illus.online resource