Light And Shadows: Realistic Renderings in Star Trek Online

Warning: this article is somewhat technical, and will be enjoyed mostly by those of you who build your own gaming content. If you don’t know much about 3D modelling and rendering – or you flunked geometry – you might want to skip this one…

Part of what makes PC and online gaming enjoyable are realistic graphics. Any first-year art student will tell you that – aside from perspective – light and shadows are the difference between eye-popping, life-like images and crude cartoons.

In the 3-D environment of gaming, realistic light and shadow effects are usually achieved at the expense of huge amounts of processing power and RAM. This is especially true of dynamic surfaces like skin and clothing illuminated by a single source light (spotlights or lamps). It is, however, less problematic for static, rigid objects illuminated by an “infinite light” (like daylight or stars) .

Happily for the developers of Star Trek Online, the main characters – starships – fall into the latter category. The initial experiments were with a technique called “pre-computed radiance,” or PRT. This is the most realistic way to reproduce complex shadows and surface scattering. It is, however, computationally very “expensive” in terms of RAM and processing resources. In practical terms, PRT works only at the vertex level – meaning more vertices produce better results. Unfortunately, more vertices also add up to a bigger model in terms of bytes, which means more processing power is required – the end result being a slower-moving game.

Further experiments were conducted with shadow mapping and stencil shadowing. The former requires no special processing on the geometry (the model itself) and has several advantages over the latter, including the ability the produce soft-edged shadows and the production of “screen-door” type transparency.

Ultimately, the decision was made to use a combination of single-point lighting and an environmental cube map. The first represents a main source of light – it this case, the nearest star. The second consists of more diffuse lighting sources, such as the ghostly glow of a nearby nebula. Shadows were created with a stenciling technique, which produced more realistic effects at close-up perspectives.

Have they been successful? Take a look at the results in the picture above and judge for yourself.

Via Gamasutra

Warning: this article is somewhat technical, and will be enjoyed mostly by those of you who build your own gaming content. If you don’t know much about 3D modelling and rendering – or you flunked geometry – you might want to skip this one…

Part of what makes PC and online gaming enjoyable are realistic graphics. Any first-year art student will tell you that – aside from perspective – light and shadows are the difference between eye-popping, life-like images and crude cartoons.

In the 3-D environment of gaming, realistic light and shadow effects are usually achieved at the expense of huge amounts of processing power and RAM. This is especially true of dynamic surfaces like skin and clothing illuminated by a single source light (spotlights or lamps). It is, however, less problematic for static, rigid objects illuminated by an “infinite light” (like daylight or stars) .

Happily for the developers of Star Trek Online, the main characters – starships – fall into the latter category. The initial experiments were with a technique called “pre-computed radiance,” or PRT. This is the most realistic way to reproduce complex shadows and surface scattering. It is, however, computationally very “expensive” in terms of RAM and processing resources. In practical terms, PRT works only at the vertex level – meaning more vertices produce better results. Unfortunately, more vertices also add up to a bigger model in terms of bytes, which means more processing power is required – the end result being a slower-moving game.

Further experiments were conducted with shadow mapping and stencil shadowing. The former requires no special processing on the geometry (the model itself) and has several advantages over the latter, including the ability the produce soft-edged shadows and the production of “screen-door” type transparency.

Ultimately, the decision was made to use a combination of single-point lighting and an environmental cube map. The first represents a main source of light – it this case, the nearest star. The second consists of more diffuse lighting sources, such as the ghostly glow of a nearby nebula. Shadows were created with a stenciling technique, which produced more realistic effects at close-up perspectives.

Have they been successful? Take a look at the results in the picture above and judge for yourself.

Via Gamasutra