[Patch] Sun Shading

[Ian]

I've read also that when you have uniform scaling in the matrix you don't need to derive (expensively) the normal matrix (or use the built-in gl_NormalMatrix), i.e. the transpose of the inverse of the model-view matrix. But you can just get the first 3 columns (3x3 mat) and directly multiplicate with the normal vector. That's why Ocean Hunters has dimmed objects.

Just tried ocean hunter with that .. and it looks correct! Yes I know you can just use the top 3x3 of the model matrix. I assumed the result of the glNormalMatrix would only be different with a non uniform scaling? I figured that was the whole point of it. Still slightly puzzled why this fixed it because I assume the scaling would be uniform??

Either way

[HarryTuttle]

The problem is that sometimes the scaling is not uniform, could that mean Real3D intelligently switches between modelViewMatrix and normalMatrix ? Still testing...

Also:
Lost World has uniform scaling, but with the modelViewMatrix you'll have over brightened t-rex's foot in the attract mode (45x scale values), maybe step 1.0 and 1.5 have different "transformMatrix * normal" logic... who knows?

[Ian]

Can you take a screenshot of the crazy foot?
Lost world has a bunch of weird normals in some of the models, always worth checking that

[HarryTuttle]

Just tried ocean hunter with that .. and it looks correct!

Speaking of which: if you look carefully at the various gameplay videos on Youtube, at the start of the first level, during the intro, the shading literally flickers, switching from dim to bright shade (as is currently rendered in Supermodel). What causes that? Cannot be a glitch on a particular hardware, since It's present in at least three different user's videos.

Is it some sort of rounding error, some value that (again) triggers a different shading model?

[Ian]

No clue!
Maybe bugs, who knows

[HarryTuttle]

Can you take a screenshot of the crazy foot?
Lost world has a bunch of weird normals in some of the models, always worth checking that

That's it:

lostw01.png (189.32 KiB) Viewed 6957 times

SWTrilogy also has some over-bright problem like that, but many times can be neutralized with the division by the node-level modelScale value.

[Ian]

This is what my current experimental build looks like


Instead of normalize the result, just divide by the model matrix scale.

[HarryTuttle]

Instead of normalize the result, just divide by the model matrix scale.

yes, but that will break again Ocean Hunter, it's like always reverting the matrix xyz scaling factor to 1.0 (circa)

[Ian]

Ocean hunter seems to look okay
However ..

I notice on the real hardware the lighting flashes on/off?? is this what you are talking about?



Most strange. It doesn't fade out, 1 min it's there, then it suddenly disappears.

[HarryTuttle]

I notice on the real hardware the lighting flashes on/off?? is this what you are talking about?

Yes, exactly that... I'm clueless