October 29, 2012

RGP day 9 - physics

So today I am doing something completely different I've done so far - the physics system. It is the next big challenge aside from the track coordinates and AI.
For collision detection and simpler stuff I will be relying on Blender's Bullet Physics system, but more advanced things - track space constraints, hover spring-damper system, vehicle handling and behaviors I will have to write from a scratch. And as an artist I am very good at it :P. Fortunately we have an Internet and there are a lot of really helpful resources for this.

The first thing I tried to implement was a mass-spring-damper system. I will be using it to make the vehicles levitate above the ground/racetrack surface. The idea is to cast a ray from the vehicle's vertical axis down. If it collides with a surface the spring-damper simulation will run and apply the calculated force to the vehicle.
The most helpful resource I found had an actual Blender Game Engine implementation already :). HERE is the link where I found it. It is done by Sebastian Korczak, same guy who is making the Burster - a web browser plugin to allow publish and play Blender files online. I will be using it at one point of development to show off the progress.
So after some changes I had a nice springy levitating box.

Another thing I managed to create - a force field that will keep the race car close to speedway's surface, thus preventing the vehicle to fall off the track surface even if the speedway is oriented upside down.

blend file HERE

October 28, 2012

shader based cube environment mapping

I present you a pure shader based cube environment mapping. It might be useful for those who, for whatever reason, does not have "samplerCube" texture type support in their engine or want some more flexibility or customization for envmaps. It is a tiny bit slower than the proper version and mip-mapping is not working well, so it is pretty much useless.
This paper helped me a lot: http://www.cs.wustl.edu/~cmg/content/papers/jgt2007em/jgt2007em.pdf

Anyways, the input can be 6 separate textures or cube environment map Blender style. A standard OpenGL style alignment is on the way.

shader HERE

screenshots are in previous post :)

October 23, 2012

//status update 04 & RGP day 8

Lots of good stuff has happened recently. I am waiting for my new custom laptop to get shipped from US, so finally I will be able to normally screencast the process of the development of my racing game ..and to actually play my game. As a real tech geek I will also write a short review of it :)
Not much has happened to RGP since the last post and I believe the real process will start whenever I will be on my new rig.

Here is the list of stuff regarding RGP:

- So for the outdoors lighting in the game I will be using a procedural sky model originally presented in 2002 GDC by Naty Hoffman and Arcot J. Preetham. Implementation by Simon Wallner seemed to be the best one I could find and I have already got it working in BGE (see it HERE). I thought I was quite satisfied with the results, but just few days ago some guy asked for an assistance regarding the sky shader as he is implementing it in UDK4 engine. It turns out I had seen his works numerous times and visited his portfolio earlier, be sure to check it out HERE <- awesome stuff! Anyways he also pointed out that it lacks the distinct sunrise feel to it so I took another look at the shader. After few modifications I came up with a nice sunset/sunrise effects.
- I also added a Uncharted2 filmic tone mapping operator from John Hable's GDC presentation and implementation of it from HERE. I really Hope I can add a real HDR support in BGE someday.
- Another feature I have been trying to replicate in BGE is generation of cubemap environment maps in real-time. I did it by simply rendering textures from 6 cameras and then combining them in a shader. It is slow but works! A simplified and optimized version of it I might use for reflection in the game.
- And the last but not least - a pseudo lens flare by John Chapman (implementation from HERE)

blends:

both files also feature point light scattering by Miles Macklin.

realtime cubemap:
https://dl.dropbox.com/u/11542084/realtime_cubemap.blend

lens flares:
https://dl.dropbox.com/u/11542084/flare_playground_3.blend

screenshots:

the upgraded sky model



real time cube environment mapping





lens flares





Battlefield3 style dusty lens



light directly into lens



October 2, 2012

RGP day7

so I've taken enough rest and today I am moving from "planning and preperation" to  "sketching and concepting" phase of the development process.

here is a fast 30 minute draft of shaping up the feel and scale of the desert planet. I will do a series of these.





Aside of the art part, today I tried Moguri's BGUI, which I will use for menu and some of in-game HUD. It looks very promising, but will require some intensive learning for me to get used to it. I am also planning to create a custom lighting engine with atmospheric scattering, aerial perspective, weather system, moon phases, etc. I will then build physics and handling mechanism on it. After I will publish first pre-alpha demo to try out.