SkyX plugin [SkyX 0.1 released! - Page 1]

[Xavyiy]

SkyX pretends to be a photorealistic, simple and fast sky simulator.

SkyX features:

• Atmosphere manager(Atmosphere information, funtions that returns the sky colour at a especified direction, ...)
• Sun, Moon and star field
• Layer clouds
• Full volumetric cloud system
• Ground atmospheric light absorcion pass(Allows you to simulate the atmospheric light absorcion in scene objects)
• HDR and LDR support
• Shader Model 2.0 capable(HLSL for the moment)
• Full integration with Hydrax 0.5.1 and code example(HydraxSkyXDemo: http://www.ogre3d.org/forums/viewtopic.php?f=11&t=52166)
• 2 example applications: Terrain & Volumetric cloud system

Screenshots:





Download:
SkyX 0.1 Api+Demos sources + Api doc: http://modclub.rigsofrods.com/xavi/SkyX/SkyX-v0.1.rar - 17.4Mb
SkyX 0.1 precompiled demos http://modclub.rigsofrods.com/xavi/SkyX ... _Demos.rar - 6.4Mb

SkyX 0.2 preview thread:
http://ogre3d.org/forums/viewtopic.php?f=11&t=67137

Hope you like it!

Xavier Verguín

[scratchyrice]

Looks great! May switch to this system from caelum, Depending on how it turns out. I like the "HDR support" part of it.

Keep up the good work!

Cheers

Scratchy

[Nargil]

Lets hope it won't be such an fps killer as hydrax
Looks promising. I like the clouds. I'd like the sky to be orange at sunset. At the moment it's rather yellow.

[scratchyrice]

Lets hope it won't be such an fps killes as hydrax

No offence, But that's like saying "Lets hope crysis wont be such an fps killer" - Of course it will be, But you get quality for the payment.

Cheers

Scratchy

[Xavyiy]

@Nargil
FPS are about 115 on my 8600GT (laptot)
Sunset colour depends of the atmosphere parameters(Inner radius, outer radius, camera height position, wavelenght coeficients, raileigh and mie multipliers, etc...)

Xavi

[Nargil]

with HDR ? Even if without HDR - still not bad, I guess.

[Xavyiy]

A very basic HDR algoritm is applied to the scene: 1 - exp(-uExposure * Colour)

[Nargil]

Good. You've got my blessing
Is also this going to be a replacement for hdrlib (SkyX integrated HDR system) or is it just the sky, and setting hdr is up to the main application ?

[Nauk]

Awesome Xavy, looking forward to it - especially knowing it comes from the same hand as Hydrax

[Virion]

this is awesome!

[Kencho]

Awesome! Looks great so far

[amigoface]

look fantastic as usual ... great work

are you planing to include a 3d cloud engine ?
if yes this is a nice implementation built with another lib
http://www.markmark.net/SkyWorks/

ciao

[altren]

I like this screenshots. Is it also possible to show some video of demo?
Earlier you used Caelum with Hydrax. Can you describe main difference between SkyX and Caelum and why you started writing your own skies.

[xadhoom]

Wow, looks very good! Because you speak of the ability to look up sky pixel colours you may be interested in Sh´s: http://www.ogre3d.org/forums/viewtopic.php?f=5&t=47393

xad

[Pyritie]

Earlier you used Caelum with Hydrax. Can you describe main difference between SkyX and Caelum and why you started writing your own skies.

I'm interested in knowing this too.

[Xavyiy]

@Nargil
As the algoritm I'm using (From GPU gems 2) is designed for HDR rendering, I've implemented a very easy and simple solution, Two options: the first one is to use the simple 1 - exp(-exposure*color) ecuation in all SkyX options, and the second one is render the SkyX materials in HDR range and then the HDR to LDR conversion is done by the main application, using they own HDR approach. You can switch between options with SkyX::setAutoHDREnable(const bool& Enable).

@Nauk, Virion, Kencho
Thanks!

@amigoface
At the moment I haven't planed to include a 3D cloud engine.
Anyway I think SkyX cloud system is pretty realistic(I've done today some modifications, now the fake volumetric effect is really nice!:) )

@altren
I'll record a video and upload it during this week.
The main reason to start my own sky plugin, is the fact that one of my aims for the 'Paradise codename' benchmark project is to use only code write by me(Except Ogre, of course!) and... what's better: use a built-in sky system, or write a generic plugin that anybody who want can use?
Differences: (just big differences)
- Atmospheric scattering algoritm
- Pixel shader requeriments(Caelum requires SM 3.0 for some components, SkyX is SM 2.0 capable)
- The cloud system(Both uses a layered-based system, but skyx clouds have basic volumetric effects using a modified kind of parallax mapping)
- Fog: SkyX simulates light absorcion using an aditional pass in objects using the same algoritm of the sky, when Calums uses a fog approach.
- HDR support(I don't know if caelum have this feature)
- Clock system: Calum have an awesome universal clock system, SkyX just have the sunrise, sunset and current time...
- Precipitation system, skyx haven't.
- Some minor features, like getting the colour of the sky in a direction simulating the GPU programs in the CPU, SkyX has, but I'm sure that caelum have a lot of features that skyx haven't, and probably it won't have.

@xadhoom
SH lighting is very easy to implement with SkyX, I think the SkyX::AtmosphereManager::getColourAt(const Ogre::Vector3& Direction) funtion is enough to get SH working , I will look into this and maybe add it as a SkyX-core feature!

Thanks for opinions!

Xavi

[Kencho]

Your plan sounds really exciting, and now I'm curious about the changes to the fake volumetric clouds Can't wait to watch the video

[Kojack]

SH lighting is very easy to implement with SkyX, I think the SkyX::AtmosphereManager::getColourAt(const Ogre::Vector3& Direction) funtion is enough to get SH working , I will look into this and maybe add it as a SkyX-core feature!

Yep, that should be enough for generating an SH of the sky. Does the getColourAt method take into account clouds and sun, or is it just the sky colour?

[Xavyiy]

Yep, that should be enough for generating an SH of the sky. Does the getColourAt method take into account clouds and sun, or is it just the sky colour?

At the moment it only takes into account sky and sun colour(Sun isn't billboard based, it's calculated in the sky shader), for clouds... maybe emulating the clouds gpu programs in the cpu for the needed pixel, but for the moment, only sky and sun colour

[yehiyaml]

Nice work.
I'd be interested to see how the fake volumetric effect turns out. Volumetric clouds have always interested me...

[DanielSefton]

Oohh! Two at a time baby, yeah!

Well, your sun looks better for a start. And the clouds indeed look a little fluffier. Atmospheric scattering and HDR will be a big bonus. Promising stuff!

We have high expectations after your awesome Hydrax plugin.

So will this paradise project be some kind of portfolio piece, or?

[Xavyiy]

@DanielSefton
Thanks
At the moment the paradise project is just an idea in my mind, but I think SkyX will be ready in some months(2/3), and the it will be a good Hydrax test , so... I feel happy about the current state of the 'Paradise' project, my idea is to have all the little plugins I'm going to use ready until the summer, and during the summer do the paradise benchmark/demo, anyway I'm going to need a good modeller/texturer that I haven't at the moment!

----------------------------------------------------------
Here is a video of the latest SkyX build, sorry about the over-exposure, but seems that the video conversion to mp4 have change a little the luminosity!
http://modclub.rigsofrods.com/xavi/SkyX ... wVideo.mp4

Xavi

[xadhoom]

Here is a video of the latest SkyX build

Wow, looks very promising! Indeed! Are the clouds just one texture (its hard to see in the video) or do you multiply different layer?
The sun with its halo looks somehow realistic

Do you have to update the e.g. skydome position to stay around the camera every frame? This approach leads to some synchronising issues in Caelum when your camera is hanging somewhere under some SceneNodes which update their position/orientation.

xad

EDIT: If you want a perfect platform for testing SkyX then you can use Ogitor with its neat PlugIn interface

[AshMcConnell]

Looks great Xavi! Keep up the good work

[trnrez]

Looks very good! Keep up the good work.