Moving On

As some of you know, a few weeks ago I left WB Games Montréal. I’ve accepted an amazing, life-changing opportunity at DICE’s Frostbite Labs to work on cutting-edge, industry-leading future graphics technologies, jaw-dropping creative experiences and other unannounced fantastic topics, with my good friend and graphics luminary Johan Andersson and a super-team of unequivocally talented engineers (Graham Wihlidal, Niklas Nummelin, …) and amazing artists.

This was not an easy decision to make. Moving to another country and leaving the (two) teams I’ve built, coworkers and friends at WBGM, and moving away from friends and family is a big deal. Building a new studio and team is not always easy, and I learned a lot. I’m grateful for the undeniable trust that was put in me, for all we’ve accomplished and have yet to show the world, and for having the opportunity to initiate & expand WB Games’ worldwide tech sharing with my friend Jon Greenberg at Netherrealm, Jared Harp and Piotr Mintus at Monolith, and everyone else who contributed. I’m convinced that you will be amazed with what is yet to come from WBGM, and from the other WB studios. 😉

The beginning of my adventure in Stockholm is coming up quickly. More on this soon! 😉


Finding Next-Gen – Part I – The Need For Robust (and Fast) Global Illumination in Games

Figure 1: Direct and Indirect Illumination from a single directional light source. [1]

This post is part of the series “Finding Next-Gen“. Original version on 2015/11/08. Liveblogging, because opinions evolve over time.

Global Illumination?

Global illumination (GI) is a family of algorithms used in computer graphics that simulate how light interacts and transfers between objects in a scene. With its roots in the Light Transport Theory (the mathematics behind energy, how it transfers between various media, and leads to visibility), GI takes into account both the light that comes directly from a light source (direct lighting/illumination), as well as how this light is reflected by and onto other surfaces (indirect lighting/illumination).

As seen in Figure 1, global illumination greatly increases the visual quality of a scene by providing a rich, organic and physically convincing simulation of light. Rather than solely depending on a manual (human) process to achieve the desired look, the mathematics behind GI allow lighting artists to create visually convincing scenes without having to worry about how they can manually replicate the complexity behind effects such as light scattering, color bleeding, or other visuals that are difficult to represent artistically using only direct illumination.

Continue reading “Finding Next-Gen – Part I – The Need For Robust (and Fast) Global Illumination in Games”

Finding Next-Gen: Index

It’s Been Awhile…

This is the index page for a series of blog posts I’m currently writing about some challenges in real-time rendering and my perspective on these topics.

In no way is this an attempt to sum it all up or provide perfect solutions, but rather add to the discussion on topics that are close and resonate with me, while respecting my various NDAs. What you will find here is undeniably inspired and fueled by the various presentations and discussions from the latest conferences, as well as from various discussions where graphics programmers tend to hang out. The following wouldn’t be possible without this amazing community of developers that share on a daily basis – thanks to everyone for the inspiration and for always sharing your discoveries and opinions! Much needed for progress.

Also, this page will most likely evolve and change. Some topics might appear, be grouped, and some might greatly change pending on how much content I can put together. Feel free to come back and check  this page over time.

Please leave comments if need be, and thanks for reading!

Finding Next-Gen

Deformable Snow and DirectX 11 in Batman: Arkham Origins

It’s been a while, but I finally found some time for a quick post to regroup the presentations I’ve done this year at the Game Developers Conference (GDC) and NVIDIA’s GPU Technology Conference (GTC). These presentations showcase and explain some of the features developed for Batman: Arkham Origins.

Continue reading “Deformable Snow and DirectX 11 in Batman: Arkham Origins”

Blending Normal Maps?

What is the best way to blend two normal maps together? Why can’t I just add two normal maps together in Photoshop? I heard that to combine two normals together, you need to add the positive components and subtract the negative components, then renormalize. Looks right to me… Why shouldn’t I be using Overlay (or a series of Photoshop blend modes) to blend normal maps together? I want to add detail to surfaces. How does one combine normal maps in real-time so that the detail normal map follows the topology described by the base normal map?

If this is something you’ve heard before, something you’ve asked yourself, check out this article, written together with Stephen Hill (@self_shadow) on the topic of blending normal maps.

Continue reading “Blending Normal Maps?”

Approximating Translucency Revisited – With “Simplified” Spherical Gaussian Exponentiation

Lately, someone at work has pointed out the approximation of translucency Marc Bouchard and I developed back at EA [1], which ended up in DICE’s Frostbite engine [2] (aka The Battlefield 3 Engine). Wanting to know more, we started browsing the slides one by one and revisiting the technique. Looking at the HLSL, an optimization came to my mind, which I’ll end up discussing in this post. In case you missed the technique, here’s a few cool screenshots made by Marc, as well as tips & tricks regarding implementing the technique and generating the inverted ambient-occlusion/thickness map. See the references for additional links.

Continue reading “Approximating Translucency Revisited – With “Simplified” Spherical Gaussian Exponentiation”

A Taste of Live Code Editing With Visual Studio’s Tracepoints

Needless to say that from one software project to another, compile times vary greatly. When debugging we often spend a significant amount of time changing some lines of code, recompiling, waiting and then relaunching the software. While it is true that one has to change their debugging “style” from one project to another (i.e. having a thorough understanding of the problem before “poking around” code is definitely a plus when dealing with big code bases where edit-and-continue is not possible), waiting for the compiler and linker when debugging is never fun. It’s also very unproductive.

In parallel, some of the tools we use everyday allow us to greatly improve our debugging efficiency, though sometimes we are completely oblivious to the power that is available to us. Regardless of how fast or slow compile and link times are on your current project, any tools that can mitigate the recompile cycle when debugging are welcome. One such tool is Visual Studio’s tracepoint: a breakpoint with a custom action associated to it.

Continue reading “A Taste of Live Code Editing With Visual Studio’s Tracepoints”

Approximating Translucency – Part II (addendum to GDC 2011 talk / GPU Pro 2 article)

Thanks to everyone who attended my GDC talk! Was quite happy to see all those faces I hadn’t seen in a while, as well as meet those whom I only had contact with via Twitter, IM or e-mail.

For those who contacted me post-GDC, it seems the content I submitted for GPU Pro 2 didn’t make it into the final samples archive. I must’ve submitted too late, or it didn’t make it to the editor. Either way, the code in the paper is the most up-to-date, so you should definitely check-it out (and/or simply buy the book)!

Roger Cordes sent the following questions. I want to share the answers, since it covers most of the questions people had after the talk:

Continue reading “Approximating Translucency – Part II (addendum to GDC 2011 talk / GPU Pro 2 article)”

GDC 2011 – Approximating Translucency for a Fast, Cheap and Convincing Subsurface Scattering Look

As presented at GDC 2011, here’s my (and the legendary Marc Bouchard) talk on our real-time approximation of translucency, featured in the Frostbite 2 engine (used for DICE’s Battlefield 3). These are the slides that we presented, along with audio. Enjoy! 🙂



Marc and I would like to thank the following people for their time, reviews and constant support:

For those we managed to meet, we had such a good time with all of you at GDC. Always happy to interact with passionate game developers – this is what makes our industry so great! We hope to see you soon again! 🙂

GDC 2011 Talks You Should Attend

As seen in the previous post, I’ll be presenting at GDC 2011. We also have several AMAZING speakers from EA (Electronic Arts) whose talk you should attend:

SPU-based Deferred Shading in BATTLEFIELD 3 for Playstation 3


Christina Coffin (DICE), @ChristinaCoffin


This session presents a detailed programmer oriented overview of our SPU based shading system implemented in DICE’s Frostbite 2 engine and how it enables more visually rich environments in BATTLEFIELD 3 and better performance over traditional GPU-only based renderers. We explain in detail how our SPU Tile-based deferred shading system is implemented, and how it supports rich material variety, High Dynamic Range Lighting, and large amounts of light sources of different types through an extensive set of culling, occlusion and optimization techniques.


Attendees will learn how SPU based shading allows a rich variety in materials, more complex lighting and enables offloading of traditional GPU work over to SPUs. Optimization techniques used to minimize SPU processing time for various scenarios will also be taught. Attendees will understand how to technically design, balance and analyze the performance of a game environment that uses an SPU based shading system. Attendees will learn key points of creating and optimizing code and data processing for high throughput shading on SPUs.

[Intended Audience]

This session is intended for advanced programmers with an understanding of current forward and deferred rendering techniques, as well as console development experience. Knowledge of lower level programming in vector intrinsic, assembly language, and structure-of-arrays versus array-of-structures data processing is recommended.


Lighting You Up in BATTLEFIELD 3


Kenny Magnusson (DICE)


This session presents a detailed overview of the new lighting system implemented in DICEs Frostbite 2 engine and how it enables us to stretch the boundaries of lighting in BATTLEFIELD 3 with its highly dynamic, varied and destructible environments. BATTLEFIELD 3 goes beyond the lighting limitations found in our previous battlefield games, while avoiding costly and static prebaked lighting without compromising quality. We discuss the technical implementation of the art direction in BATTLEFIELD 3, the workflows we created for it as well as how all the individual lighting components fit together: deferred rendering, HDR, dynamic radiosity and particle lighting.


Attendees will learn the workflow we use to light our worlds, as well as memory and performance considerations to hit our performance budgets from a technical art perspective. Attendees will also get a thorough insight into an exciting new approach to lighting both open landscapes and indoor environments with dynamic radiosity in a fully destructible world.

[Intended Audience]

Attendees should understand the fundamentals of lighting systems used in contemporary game development as well as basic principles of rendering technology. Primarily directed at technical artist and rendering programmers, the presentation is accessible enough that anyone attending will gain an insight into the world of lighting.


Advanced Visual Effects with DirectX 11


Johan Andersson (DICE, @repi), Evan Hart (NVIDIA), Richard Huddy (AMD), Nicolas Thibieroz (AMD), Cem Cebenoyan (NVIDIA), Jon Story (AMD), John McDonald (NVIDIA Corporation), Jon Jansen (NVIDIA Corp), Holger Grn (AMD), Takahiro Harada (Havok) and Nathan Hoobler (NVIDIA)


Brought to you with the collaboration of the industry’s leading hardware and software vendors, this day-long tutorial provides an in-depth look at the Direct3D technologies in DirectX 11 and how they can be applied to cutting-edge PC game graphics for GPUs and APUs. This year we focus exclusively on DirectX 11, examining a variety of special effects which illustrate its use in real game content. This will include detailed presentations from AMD and NVIDIAs demo and developer support teams as well as some of the top game developers who ship real games into the marketplace. In addition to illustrating the details of rendering advanced real-time visual effects, this tutorial will cover a series of vendor-neutral optimizations that developers need to keep in mind when designing their engines and shaders.


Attendees will gain greater insights into advanced utilization of the Direct3D 11 graphics API as used in popular shipping titles.

[Intended Audience]

The intended audience for this session is a graphics programmer who is planning or actively developing a Direct3D 11 application.


Culling the Battlefield: Data Oriented Design in Practice


Daniel Collin (DICE), @daniel_collin


This talk will highlight the evolution of the object culling system used in the Frostbite engine over the years and why we decide to rewrite a system for BATTLEFIELD 3 that had worked well for 4 shipping titles. The new culling system is developed using a data oriented design that favors simple data layouts which enables very efficient computation using pipelined vector instructions. Concrete examples of how code is developed with this approach and the implications and benefits compared to traditional tree-based systems will be given.


Attendees will learn how to apply data oriented design in practice to write simple but high throughput code that works well on all platforms. This is especially important for the current consoles.

[Intended Audience]

Intended for programmers on all levels but some background on vector math and basic threading would be beneficial.


Four Guns West


Ben Minto (DICE), Chuck Russom (Chuck Russom FX), Jeffrey Wesevich (38 Studios), Chris Sweetman (Splash Damage Ltd.), and Charles Maynes (Freelance)


This session aims to give an insight into the shadowy world of audio in AAA FPS titles. Featuring the sound designers behind MEDAL OF HONOR, BRINK, BLACK, HBO’s THE PACIFIC, and CALL OF DUTY. The face off is split into bite size chunks concentrating on key areas that are required to design the weapon audio for a AAA shooter. Areas of focus will include insight into Weapons Field Recording headed up by Charles Maynes, Sound Design with Chuck Russom, Creating Believable Worlds and Mixing Practices with Ben Minto, and Real vs Hyper Real with Chris Sweetman. The panel will also discuss the emotional power of weapon sound design in Video Games & Film.


New attendees will get tips and tactics on approaching audio in an FPS which can then be applied to their own productions. It will empower producers and game designers to consider audio early in a titles development which will increase the player’s experience and enjoyment tenfold.

[Intended Audience]

Target audience will be sound designers,producers, game designers and creatives from all aspects of video games wanting insight into the tricks behind great sounding AAA titles. The session will be structured to allow for all levels of knowledge in the specific fields.