[Bf-committers] 2.28 Ahoy 2!
Nathan Vegdahl
bf-committers@blender.org
Thu, 24 Jul 2003 02:31:02 -0700 (PDT)
> - the commits you did for this system were so many, that I could not
> locate all changes for it. So I've loaded tuhopuu.exe, checked what I
> liked from it, and started over from scratch.
Heh... yeah, I wasn't very good about that. :-/
> - Yep, I completely forgot about the texture channels for it. A nice
> addition for a 2.29 release!
Yes, I suppose people can just use tuhopuu if they need to until then. :-)
> - The buttons layout you did in Tuhopuu really was messy, with buttons
> crammed together below a minimum acceptible size.
As I said: my vote doesn't count, because I'd be biased. :-)
> we now really need a method to expand buttons easier. Proposals for
> that are being discussed.
Cool. I look forward to seeing what you guys come up with. :-)
> - I found some tuhopuu code that related to shader plugins, but could
> not find clues how it was supposed to work.
Yeah... I should have commented it better. Sorry about that. I'm rather
bad at commenting when I'm not programming from scratch. :-/
> Apart from that, I don't even *know* if we want it in bf-blender. Plugins in
> the past (texture, sequence) only have given us troubles. My preference is to
> look first if we can do this with Python. The python coders already
> investigate feasibility. Then at least we have something stable & cross
> platform. I am very confident the current implementation can easily be
> tweaked for such plugins. Let's first discuss & research this topic!
Hmm... I don't really see a point in implimenting it if it wouldn't be used
in bf-blender. I think I'll hold off on implimenting it until you do know. In
the mean time, I have other things I want to work on in Blender. Of course,
that will still have to wait until school starts...
> - Blender already used the 'hardness' value to determine specular size.
> I decided to copy that for Blinn, since it works almost the same. I
> transformed the hardness integer value to a float, with a formula
> that's close to what Phong and CookTorrance offer. The 'roughness' you
> provided in Tuhopuu was impossible to work with... with a slider which
> offered the most interesting results in the lower 1% of the values.
> I realize what i did is not 'scientifically correct'... it was just a
> quick decision, with the aim to make something that worked. I also
> didn't know the Blinn roughness was tied to Oren's roughness. In all
> articles I read about it, I couldn't find a reference for it.
It's never stated directly anywhere that I know of, but if you read both
papers, you will notice two things:
- they both use the micro-facet surface model as their basis
- they both use gaussian distributions as the statistical micro-facet
distribution model.
Because of that, if they are both given the same parameters, they will both
be representing a surface with identical properties. Which, of course, is why
it's ironic that in 3D-studio max the two distribution parameters don't
correspond to each other. I suppose I was trying to out-do them. :-)
I still think that the Blinn parameter should be reverted to how I had it,
but I'll leave that to your descretion.
> Again, no harm done if we decide later on to change it. Blender
> filereader can convert it.
Oh! I forgot about that. Yes, of course.
> Cessen, I really liked your idea to improve the shading in Blender, and
> the code for the math was extremely welcome. I will be glad to further
> work with you on this, and come together with improvements for further
> releases.
I think one thing we can do to improve it is to simply add more shaders for
people to use. The more flexability, the better! :-)
--Nathan "Cessen" Vegdahl
__________________________________
Do you Yahoo!?
Yahoo! SiteBuilder - Free, easy-to-use web site design software
http://sitebuilder.yahoo.com