Racer v0.8.20 is out

[Ruud]

Yep, just these changes (Mitch has been working on a GL wrapper, mostly for debugging, I've been doing mostly work on other versions):

- Set gamma to 1.0 in data/renderer/common/hdr.cg - gamma is done in your display!
- Added shader texture option 'mode' to specify linear or SRGB maps. Default is 'srgb'. Bumpmaps need 'linear'
otherwise their normals will be un-gamma'd (an SRGB image has gamma~0.45 where Racer works in linear light, gamma=1).

It's at http://www.racer.nl/download/racer0.8.20.zip

Check out Carlswood's track.shd and the Lambo car.shd to see 'mode=linear' being used for linear textures.
As for bugs, we're having some issues where sometimes we get a 'cgiChopArrayReference' or something creeps up. Mitch is looking into it.

 

[DavidI]

Agreed, but remember the beta in 0.8.20, the Cg needs optimising as MitchVL's already said, hopefully he &/or Ruud have already looked at it, I just turn shadows off for racing & dev, & turn it on for screenies.
Two steps forward one step back & a kick in the pants, Racer forever...

 

[KS95]

Two steps forward one step back & a kick in the pants, Racer forever...

You've gotta love it

 

[DavidI]

Can a moveable object be assigned a collision sound eg like a shopping trolley has that annoying rattly metalic noise, can I assign that to my shopping trolley moveables so when u collide with them it triggers? or a 'fwop' sound for cones?

Hint for anyone making moveable objects using collison model type 2 - the collision model is taken from the first materials poly's only, so u need to make sure the first material mesh defines the extents of the model.
u can cheat by putting some polys at the outer extremes assigned the first material & mapped to a trasparent pixel or ten. this makes sure the collision model surrounds the whole model

 

[luthobu]

Sure, there was a thread on that a while back. I'll update this post when and if I find it..
Else you have Ruuds documentation here: http://www.racer.nl/tutorial/materials.htm

 

[DavidI]

Thanks, hadn't noticed that page, awesome, now all I need are sonme shopping trolley samples.
lol, I'm going to define an ear curdling scream to people & crowd textures.

[edit] good to see the forums back.

Only thing wrong I can see here is that the physics materials are defined globally, can we have a materials.ini per track please?

 

[Mr Whippy]

Hmmm,

Just messing with shadows a bit more.

And the sun/sky/TOD stuff.

Still too complex imo.

Right now I feel like once we have set lat/long/date/time, the sun arc is known. The sun powers EVERYTHING from that point onwards. It's intensity is fixed in space, so the adjustment is made due to the atmosphere.

Atmosphere is driven by mie/ray and extinction point, and the cloud cover. Those are the main values we should need to tweak.

Still ignoring the actual diffuse/ambient values we set, the sun_intensity curve is a key one to know. Once this is set, the sky is then generated, and from that we get the colours we need to populate the sun diffuse/ambient curves. In my mind, those six curves (rgb diffuse, rgb ambient) are a function of mie/ray and sun_intensity.

Then, the impact of cloud simply adjusts those curves again. Maybe that can even be calculated as a term that impacts sun_intensity, and/or through the same calculation as mie/ray impacts on the sky colour/intensity for rendering purposes (and then calculation of sun ambient colouring/intensity for car/track illumination)

We can also then have a lookup at the sun size against the sky, so as it gets bigger and softer the shadow blur is adjusted, so we can get softer shadows on certain days.


Just playing lots and thinking how much more could and probably should be automated.


Still struggling with the sky/night shading too, we go from no texture during the day to a night time sky texture for the night. This seems open to error. Not better to have mie/ray method calculate the sky background as per daytime, and then use a texture with alpha to replace the star field?
The moon could easily be added into the sky and moved around this way too.

Hmmmm, just thoughts about things. Drawing accurate curves that look right is a pain when the real controls I need are mainly mie/ray and cloud cover... with extinction factor set by eye easily...

Dave

 

[DavidI]

Only thing wrong I can see here is that the physics materials are defined globally, can we have a materials.ini per track please?

GRRR... Second annoyance is that you can't seem to set the export order for materials in ZMod, and the first material isn't the one I wnat used for the collision model. Could we also be given the ability to specify the material used for the collision hull?

 

[MitchVL]

a stone wall is a stone wall, i would not expect it to behave differently on different tracks imo

 

[DavidI]

a stone wall is a stone wall, i would not expect it to behave differently on different tracks imo

Yes, but does every track NEED a shopping trolley effect? And do I have to register my material with Ruud or yourself to get it into the standard materials? imho easier to have racer read the default list as now, and additionally append any track material.ini to it, like car.ini is currently.
I haven't even started Cg'ing my alien world track, I'm guessing that I would like to be able to make a stone wall to NOT be a stone wall in some respects. Flexibilty is what makes Racer great.

 

[MitchVL]

you have a point there, you guys are really thinking out of the box when using these features.
When i started working on materials, i was not thinking about shopping trolley materials or anything other than the basic materials like stone, metal, ...

Request noted !

 

[DavidI]

While your at it, I've been banging on for a while about having similar overrides for gravity & air density in track special.ini. While not needed normally, high altitude & non-earth tracks need the ability to change these.
At one stage there was discussion with Ruud over air density in general, that it should be able to be calculated from base sea level pressure by car's altitude. I suppose it is in the todo list somewhere.
(I've wanted to do a moon track and Lunar rovers for ages, having these in special.ini would push me to doing it & with all the other changes my Dodgem car track & dodgem cars might even work well now)

 

[boomer541]

For Mr. Whippy, TOD info:
The only items in the special.ini file that have any effect and need to be adjusted first are for my carlswood settings:
1. exposure=ex. 0.035
2. time=ex. 1000
3. ;Sun path parameters
year=ex. 2010
month=ex. 8
day=ex. 21
latitude=ex. 53.9240
longitude=ex. -0.9888
timezone=ex. 1
4. azimuth_offset=ex. 180 ;rotates sun position, not very useful and s/b set to rotate East to West as in real life, other tracks = 0
5. clouds=ex. 0.5

Then I do the tod curves paying attention to the day/night transition so that the sun is visible just above the horizon..
Number 3 thru 4 are placed just under the sun=-93 24 -26, above the {. azimuth_offset has no effect if placed here. If placed under the { then the only difference between two identical special.ini files is one uses .jpg vs .tga textures. Therefore a question about sky texture being .jpg vs. .tga. I haven't check that out yet.

The initial settings should be done with auto_exposure off.

 

[luthobu]

a stone wall is a stone wall, i would not expect it to behave differently on different tracks imo

Which brings to mind.. since a stone wall is a stone wall, and headlights are glass.. would it be possible to disable the lights after a frontal? Maybe even a sound of the headlights being smashed? That would be a nice feature, and yet annoying.. but it is a sim, right? If you frontal, you smash the headlights.. Also it would be nice to have some "flat tire" option, like after we hit DavidI's trolleys and one of the spokes punctures a wheel.. LOL

Also it would be nice if the physics for earth conditions were optimized before we start thinking about the moon..

 

[DavidI]

I DO care about the physics, I want a real working monster truck suspension & 4WD same as anyone, & physics is physics anywhere in the universe. They are a few simple changes that'd add a great deal to Racer's flexibilty & realism. I AM a trackmaker first, car (in a stretched sense of the word) tinkerer second.
ps. I reckon a 64bit Racer would improve the suspension for heavy vehicles

 

[boomer541]

more for Mr Whippy:
Using .jpg or .tga textures in the track shd file makes no difference in positioning of the sun, only scene brightness. The sun doesn't transition from horizon to horizon. .tga's made scene too dark.

Azimuth_offset=180 transitions from West to East and azimuth_offset=0 transitions from East to west as in real life on 2ndcreek whe item 3 thru 4 are placed under the {. azimuth_offset=0 or 180 makes no difference when placed above the {, the transition is East to West. but the sun goes dark before reaching the horizon.

On my Surfaces and sounds track with item 3 thru 4 placed above the { the sun transitions from horizon to hoizon but gets dark too early at day to night time. When placed below the { the sun doen't transition from hoizon to horizon.

Sky .dof for both tracks made the same way. Both use the same cg files in the sky shader and the special.ini files use the same settings.

So what the h--- is causing the differnt performane of the two tracks.

 

[asasinuxp]

Question for Ruudapproximately) when will be ready the next version?

 

[Ruud]

Hmmm, so despite this being a new release, we should still alter the gamma value in hdr.cg?
...Am I missing something here? Is Ruuds commenting saying to us to set gamma to 1, or is he saying that is what he did, and we don't need to concern ourselves with it?!

Just getting around to start reading about the 0.8.20 comments...
Gamma should indeed be 1.0, or in other words, nothing changes. Your monitor will apply a gamma of 2.2 to whatever linear (VGA/DVI) signal you send it. So that's where gamma takes place. Racer tries to output linear colors.

For that, it needs linear textures. Most textures are made with a camera, where the camera applies a gamma of 1/2.2 to get things looking good on a monitor.
So: camera catches linear light - camera applies gamma as col=pow(col,1/2.2) - camera saves jpeg - explorer shows image - image goes to monitor - monitor applies gamma as col=pow(col,2.2) which is hardware.

Since cameras process photographs with the inverse gamma of 2.2, the contents of most textures is NOT linear. But as Racer does lighting linearly (like: diffuse=2 2 2 -> col=2*col) you need linear texture inputs. So each texture loaded from a .shd file is preprocessed to become linear (gamma 2.2 applied at load time). Then the texture is used in the engine and a linear image is output.
Some images are generated and thus Racer would make the mistake of pre-gamma'ing it. Therefore you have 'mode=linear'; from Carlswood's track.shd:

shader_road~vf_road
{
diffuse=0.5 0.5 0.5
cast_shadow=0
layer0
{
map=road.tga
}
layer1
{
map=road-add.tga
mode=linear
}
}

Here, road-add is generated and you don't want to gamma-correct it, since that would move the gray point. For bumpmaps things are also bad since you'd get normals that are bent slightly by default.

Hope that makes things clearer.

 

[Mr Whippy]

Yep, I read that huge PDF file which made it all much clearer.

Though I didn't agree with one issue, which was AO over ambient only. In practice it works nicely, but in our much more accurate world we are getting in Racer, it's too simplified to do it that way I think. With HDR ranges, any AO in diffuse lit areas will be of such low magnitude it will be 'drowned out' anyway... only in LDR lit environments does it seem important to do that


Bit off topic there.


Glad to see you back Ruud. I've been playing LOADS more with some toys I bought in real life. I now have three devices for measuring Lux haha... trying to get some relatively hard and fast rules laid down for what are normal intensity levels for both the sky/sun (direct), and the measured illumination on ground materials, in an attempt to get an idea of the balance between what Racer generates for the sun/sky colours (sun intensity related stuff), and the ambient/diffuse curves which then light things up.

It would be really nice to have the intensities from the generated sky dome determine the ambient/diffuse values for scene lighting.

The one area I'm still struggling with is clouds. I'm still preferring large clouds = numbers to get them to show up nicely. Ie, on a sunny day today, the bluey sky may be about 5-10k Lux, but the clouds either opposite the sun, or backing the sun, are between two to four times more intense! The ones in Racer simply can't do that unless I put clouds = 4 or such...


Hmmmm

Dave

 

[Ruud]

My version 0.0820 racer.ini file changes:

...
dbg_controls.road_noise_factor=0.0 ;set in special.ini or some cars won't move

Note that road_noise_factor=0 just turns off all road noise effectively.

 

[boomer541]

Note that road_noise_factor=0 just turns off all road noise effectively.

I turn off road noise as there are a couple of cars that won't move unless it = 0. I don't use them anymore and have been thinking about setting it at 0.001.

Anyway, glad to see you back Ruud, now about the day/night problems with carlswood...