The Speed of Light

The Speed of Light

By Chris Doran

July 8th 2011 at 10:00AM

Geomerics founder Chris Doran looks at the latest real-time lighting technologies

An anonymous developer, formerly of Realtime Worlds, once said: “There are two types of studio: those that believe that iteration times are important, and those that are wrong.”

Studios differ enormously in how they put together their art pipelines. All want better iteration times, but many struggle to achieve this. It is difficult to distance ourselves from the belief that long asset build times are a sacrifice that must be made to achieve great visual quality. After all, surely those twelve hours of solid number crunching add value? But this is dangerous ground. Without realising it we replace the freedom and creativity our artists require with black-box computation, and convince ourselves that his is necessary and unavoidable.

At Geomerics we have been strong advocates of dynamic lighting in games, but since the launch of Enlighten we have seen a rise in the number of studios using our product purely to enhance quality and productivity off-line. There is a clear requirement for tools that enable faster lighting workflow.

KILLER INSTINCTS

If you are pre-baking all of the lighting in a game level there are essentially two directions that a studio can take. The first is to devote all of the resources into high-end rendering technology.

In this scheme the artist has to rely on their instincts to decide how a level will look based on crude pre-visualisations. They then hit the big ‘render’ button and wait. All of the final details of the scene, including global illumination, AO and other effects, are entirely reliant on the black-box rendering algorithms. Artists can become astonishingly skilled at predicting the outputs of the renderer, but they have very limited control and many find the workflow unsatisfactory. Rendering can also become a real bottleneck in game design. Every time a piece of level geometry is altered you have to wait for another long render before returning to testing the game. This inability to quickly iterate on gameplay and design simultaneously can seriously compromise the final game.

Many studios have developed workarounds for this problem. One typical strategy is to develop the game using a low quality render that can be updated relatively quickly. This is used for iterating on the design. When all aspects are settled the final renders are produced, often close to release. This approach is clearly viable, and good art teams can mentally envision the final render.

But it is still a major compromise. Lighting is relegated to something added in the final stages, rather than an intrinsic part of the design process, and no time is left for iterating on the final look.

RADICAL ALTERNATIVES

Recently we have seen a dramatic rise in interest in a radical alternative approach. Instead of waiting for long renders, can artists take advantage of the latest real-time tools to get instant feedback on their work?

The advantages are obvious. Waiting for the final render is no longer a bottleneck in designing and testing gameplay; artists can work far more efficiently; and they can raise graphical quality. The final point is the one that surprises studios.

How can the latest and greatest real-time lighting technologies possibly compete with a twelve-hour render? The answer is down to giving control back to the artist. With real-time feedback inside a world editor the artist can keep iterating until they achieve the complete look they are after. They can vary settings interactively and mess with the laws of physics – or indeed, the laws of game lighting. If necessary, these modifications can be applied locally to provide just the right level of colour bleed, or detail in a soft shadow.

At Geomerics we are working with customers to broaden out Enlighten, offering real-time lighting both in game and in editor.

Even if the final lighting in a level is being baked, studios are discovering they can achieve higher quality, more quickly, by giving their artists more powerful real-time tools.

The holy grail of these developments is to remove the term ‘bake’ from the language of games development. We believe artists should ultimately be able to set up their lighting configuration, tweak it with instant response, and hit ‘save’ when they are done. With tools like Enlighten this is becoming a reality.

www.geomerics.com