Another preview - cloud shadows

[chris]

It's about time that I got around to this:

No cloud shadows:


With cloud shadows:


Unfortunately, there's no way that cloud shadows will work with tiled cloud textures.

--Chris

[bh]

Wow! Chris what a difference that makes. Not for 1.4.1 then I guess?

[Paolo]

. I have no words.

[Johaen]

How do the shadows work? Are they directly beneath the clouds? Are they all off to one specific side at a certain distance? Or are they like real shadows, and depend on the angle of the Sun, kinda like the eclipse shadows work?

[buggs_moran]

HOORAY!

[t00fri]

I think what we URGENTLY would need next at the OpenGl front is better atmospheres!!

Cheers,
Fridger

[chris]

I think what we URGENTLY would need next at the OpenGl front is better atmospheres!!

I agree completely. Here's my list of priorities right now:

- Finish cloud shadows (easy)
- Fix bugs in new star rendering code
- Prerelease? (if everyone on the dev list agrees)
- New atmosphere code
- Realistic planet surface illumination (Lommel-Seeliger or some approximation)
- Lots of work on accuracy--better orbital calculations, precession, coordinates systems

--Chris

[Dollan]

Oh, that is absolutely outstanding! I hope this will be in the next pre-release, indeed (but I'm patient if it won't be).

...John...

[t00fri]

I think what we URGENTLY would need next at the OpenGl front is better atmospheres!!

I agree completely. Here's my list of priorities right now:

- Finish cloud shadows (easy)
- Fix bugs in new star rendering code
- Prerelease? (if everyone on the dev list agrees)
- New atmosphere code
- Realistic planet surface illumination (Lommel-Seeliger or some approximation)
- Lots of work on accuracy--better orbital calculations, precession, coordinates systems

--Chris

Just to complement from my side:

-- adding in the rendering of lacking DSO's in PNG format:

** galactic clusters
** (planetary, bipolar) nebulae

-- asteroids??

-- implementing /extended/ Hubble classses of galaxies
-- implementing /custom/ templates (Milky way...)
-- experimenting with PNG alpha channels in the context of DSO's!

Bye Fridger

[julesstoop]

Very nice progress you are making Chris!
Thank you and the other developers for keeping Celestia alive and kicking.

[Dollan]

Just to complement from my side:

...
** (planetary, bipolar) nebulae
...

Just out of curiosity, and if you don't mind my asking, what are you thinking of in regards to planetary nebulae? Would you go with (at least initially) a uniform model for all of them?

...John...

[ElChristou]

...
Unfortunately, there's no way that cloud shadows will work with tiled cloud textures.

What a pity... no way to imagine a trick? I mean if the elegant way (true shadows) are impossible, perhaps allowing another layer of something else to create a fake shadow?

[rthorvald]

This is great! Really! Thanks!

Here's my list of priorities right now:
- Prerelease?

If there is going to be a prerelease soon, i hope and wish that Christophe??s small InfoUrl patch goes into it:
http://celestiaproject.net/forum/viewtopic.php?t=9475
... It would do wonders for my current project...

- rthorvald

[PlutonianEmpire]

Question: how will all the new stuff affect performance, especially on low end computers like mine?

[chris]

Question: how will all the new stuff affect performance, especially on low end computers like mine?

The performance of the new rendering code mostly depends on your graphics card. What do you have in your system?

--Chris

[PlutonianEmpire]

Question: how will all the new stuff affect performance, especially on low end computers like mine?

The performance of the new rendering code mostly depends on your graphics card. What do you have in your system?

--Chris

A nvidia GeForce FX go5200 graphics card.

[chris]

How do the shadows work? Are they directly beneath the clouds? Are they all off to one specific side at a certain distance? Or are they like real shadows, and depend on the angle of the Sun, kinda like the eclipse shadows work?

The shadows are 'real' and do depend upon the angle of the Sun. The calculation must be done at each vertex and is therefore rather computationally expensive (though I've no trouble running at 60Hz on my computer.)

--Chris

[Chuft-Captain]

Firstly I'd just like to say this work and your other work on improved rendering looks absolutely awesome Chris. Unfortunately I won't be able to benefit from any of this as I don't have OpenGL 2.0 graphics.
This could well be the release that finally forces me to upgrade my desktop memory and graphics (perhaps to a Nvidia card).
Although I use the laptop to do most of my modelling etc, there's probably no way to upgrade the laptop )

Just one question about the following list of priorities. I see that depth-sorting issues is not on the list. Have you given up on that Chris?, or just forgot to mention it? Or have you fixed it already? (***typed with a hopeful tone*** )

I agree completely. Here's my list of priorities right now:

- Finish cloud shadows (easy)
- Fix bugs in new star rendering code
- Prerelease? (if everyone on the dev list agrees)
- New atmosphere code
- Realistic planet surface illumination (Lommel-Seeliger or some approximation)
- Lots of work on accuracy--better orbital calculations, precession, coordinates systems

[chris]

Firstly I'd just like to say this work and your other work on improved rendering looks absolutely awesome Chris. Unfortunately I won't be able to benefit from any of this as I don't have OpenGL 2.0 graphics.
This could well be the release that finally forces me to upgrade my desktop memory and graphics (perhaps to a Nvidia card).

Celestia will continue to support older graphics hardware, but a lot of the new rendering methods are only practical on OpenGL 2.0/DX9 capable hardware.

Just one question about the following list of priorities. I see that depth-sorting issues is not on the list. Have you given up on that Chris?, or just forgot to mention it? Or have you fixed it already? (***typed with a hopeful tone*** )

I should have put that on the list too. I recently fixed one depth sorting bug that Selden had alerted me about. But, if you're talking about depth sorting of transparent objects, that's a ways off.

--Chris

[chris]

Another screenshot, this time using Don Edwards's 4k cloud texture:



--Chris