Sunday, October 31, 2010

Speed of Light

We've had this idea some time ago - to experience how fast the speed of light actually is by flying away from the planet in Outerra at that speed. Now I've made a short video showing exactly that - flying away from the surface to space, and then returning back (but overshooting past it).

And while the speed is indeed great, one can feel that's also terribly slow when considering the extents of space ..

Saturday, October 30, 2010

Apache helicopter

Here comes another video, this time with Apache AH-64 helicopter or two in it.We went to add a helicopter after the support for them has been recently added to JSBSim library. There still seem to be some bugs and our parameters for the model aren't entirely right either, so the behavior might not be absolutely correct.

Still, flying the helicopter is a great fun. I wasn't able to fly helicopter in a simulator before, probably just because I never tried hard enough. But flying it here - over the forests and through the canyons and close to the rocky walls - that gives it a completely different feeling and experience, so even the types of me can get easily lost in time while wandering over the unknown lands here.

In case you are wondering, the camera comes out from the Hydra rocket launcher at the beginning of the video, made possible thanks to the use of logarithmic depth buffer.

In order to make this video we added support for "translucent" shadows so that the shadows from rotor blades look more natural, the hard shadows were quite disturbing.

Since the last blog update a number of things has been worked on - an updated atmospheric rendering code resulting in nicer and faster atmosphere rendering, while being also more consistent in various settings. There should be a separate and more technically oriented post about that for people who are fighting with atmospheric scattering which is quite hard to get right. And of course I need to write something about it so I can find how it works later when it drops off of my brain completely again.

As a part of the atmospheric code also the ambient light has been tweaked so the shaded and shadowed terrain is now looking better; this shows best on the features of rocks - previously it didn't have the right amount of contrast and looked quite bland.

Another batch of work done concentrated on GPU memory consumption optimizations; large terrains are quite demanding in this regard so an effective management of it is essential. We managed to save bits of memory here and there by employing various hacks and different formats, which totaled to hundreds of megabytes in the end. But while someone had to effort and tweak the system to save the megabytes, someone else just had to delete that dummy 80MB buffer that was sitting there :-)

Lastly, here are some screenshots with the helicopters:

Forum topic - Apache helicopter.