The Future of Triangles Part 3: X-Plane 9

Before I post anything to my blog saying what might happen, standard disclaimers:

• This blog represents my rambling about the directions I am considering for X-Plane's rendering engine.
• This blog is not a promise or commitment of any kind to deliver any particular feature.
• If I say I am looking at doing feature X, and feature X does not materialize, either in the near or far future, or, like, ever, consider this to be one big fat "I told you so."

With that in mind, I think the direction for lighting in version 9 is to introduce per-pixel lighting.

I don't know what other set of features we'll get with per-pixel lighting, but I am reviewing normal maps, specular maps, and the material attributes.  Per pixel lighting will mean smooth, round, shiny looking surfaces without using a huge number of triangles.

Now there are two sets of hardware that will not be able to support per-pixel lighting:

• Cards without pixel shaders.  (GeForce 2,3,4, Radeon 7000-9200.)  You might know your card does not have pixel shaders because the pixel shader check box is not available in the rendering settings.
• Cards with first generation shaders.  (This is the GeForce FX series and the Radeon 9500-9800 and X300-X600.)  These cards can actually perform per-pixel lighting, but they are so slow that per-pixel lighting will bring them below minimum frame-rate.

So unfortunately, there will be an authoring decision: add more triangles so that per-vertex lighting looks good, or use fewer triangles and rely on per-pixel lighting.  The decision will depend on what hardware you want to target at what performance level.  (For what it's worth, hardware that cannot support per-pixel lighting usually isn't very powerful, so there is something to be said for not having a lot of triangles on these lower end machines.)