Tech Interview: Trials HD
Sebastian Aaltonen and Antti Ilvessuo discuss the technology behind this year's top XBLA game.
For many smaller developers it's both a budget and technology issue. Most arcade developers do not have the budget required to license an AAA-grade commercial graphics engine or do not have enough highly skilled technical programmers to write their own high-end graphics engine, content tools and content pipeline. The quality of art and models are also becoming a more and more important thing in new games, as technology has become good enough to materialise most of the requirements set by the graphics design. Without enough talented artists to model and texture the whole game world, the graphics technology doesn't really matter. Technology and art need to be balanced properly to get the best result.
At the moment we have no plans to take Trials HD to other platforms. We've been really pleased with XBLA. Microsoft's development tools have been excellent and the hardware has been straightforward to support and to optimise for. The development support has also been really fast and professional, and the game itself has been a big success.
Trials HD technology has been specially designed for the Xbox 360 feature-set. We are doing all our particle animation and processing using the GPU/memexport and we use eDRAM and its bandwidth-free anti-aliasing hardware in many clever ways to speed up our graphics processing algorithms. The modified ESM soft shadow algorithm we use is very well suited for the Xbox 360 architecture. A PC port would be pretty straightforward, as modern PC hardware is more powerful than Xbox 360 and the the DX10 API supports all the hardware features our technology needs.
In general, RedLynx has always been developing games for multiple platforms, and our in-house engine technology supports multiple platform development really well. So far we have released games for Windows, Linux, Apple Mac, Apple iPhone, Nokia N-Gage, Sony PSP, Nintendo DS, Xbox 360, interactive TV and to many mobile phones.
I think it is not really a hardware question as to why the tessellators in current GPUs haven't been used that much by the majority of the game developers. Porting fully-polygon-based graphics engines, content creation tools, content creation pipelines and storage formats to support curved surfaces is a huge task. Most graphics artists in the game development industry are used to polygon-based modelling programs, and polygon-based modelling tools have become really advanced and widely supported. It will take some time for the game development industry to start using curved surfaces as the main geometry definition, storage and rendering format.
This is a really hard question to answer. Neither of the current-generation leading consoles have been fully utilised yet. We are getting close, but there are still so many little things that developers can do more optimally to squeeze the last bits of performance out of the current consoles. I think that more general vector data GPU-processing via memexport and custom vfetch are some of the things that can be used on Xbox 360. In some ways the Xbox 360 GPU is more flexible than current PC DX10 hardware.
Trials HD has been programmed to support DLC packs straight from the beginning. The game supports easy addition of new tracks, new tournaments and new level editor objects with just a data update. A DLC pack also allows us to have three more Xbox Live Achievements, worth a total of 50 gamerscore. We know from the past experience with Trials 2 that the hardcore fans will need their daily dose of new tracks on a regular basis. And we will surely deliver our fans exactly that!
Speaking of Trials HD fans... it seems that our fan base has expanded rapidly since the Trials HD release. According to the latest Major Nelson's official Xbox Live analysis we sold more copies last week than any other Xbox Live Arcade game. And this includes Shadow Complex, a game released only a week before the analysed period of time. Our fans also seem to keep pounding the Xbox servers sending better and better scores week after week in an accelerating fashion. The huge amount of individual active Trials HD players has put the game on the total top 10 most-played Xbox 360 games chart. It's a huge feat for a Live Arcade game.