Comments for adruab.net

Comment on Stenciling for “deferred” lighting by adruab

adruab — Mon, 13 Jul 2009 00:22:07 +0000

And actually come to think of it you might still be able to do single mad by computing the following in the vertex shader: ProjectToFarPlane(posWorld – posCamera). There may be issues with correct interpolation for geometry clipping through near/far, but you might be able to get around that with trickery.

Comment on Stenciling for “deferred” lighting by adruab

adruab — Fri, 10 Jul 2009 03:22:57 +0000

We read directly from the depth buffer and thus don’t have linear z . 3 components of the reverse projection matrix can be factored into the vertex shader, so you do perspective space Z * matClipToWorld[2] + vecXYW (float4 interpolated from vertex shader). Then you have a divide (recip + mul). So yes, it’s 3 instructions and 1 interpolant instead of 1-2, but you don’t have to store linear Z (full screen worth of RAM). Reconstructing perspective Z rather than sampling from a globally stored linear Z buffer, takes 3 instructions itself (on the RSX at least). I think a better argument for screen space tiles than saving a few arithmetic instructions is merging multiple lights to reduce (and potentially maximize cache reuse) for sampling giant textures. We’ll probably try tiles again. However, stencil culling still feels like potentially anti-useful trade off.

Comment on Stenciling for “deferred” lighting by JSeb

JSeb — Tue, 30 Jun 2009 14:55:53 +0000

Hi,

I think you forgot one “con” for the alternate approach:
some arithmetics of position reconstruction can be move to vertex part, but only when you render a full quad.
(in pixel pipe, you can reconstruct position from linear_z with only a mad and 2 interpolants)

When you render a bounding geometry, the position reconstruction can no longer be prepared in vertex space.

Comment on Stenciling for “deferred” lighting by realtimecollisiondetection.net - the blog » Catching up (part 2)

realtimecollisiondetection.net - the blog » Catching up (part 2) — Mon, 08 Jun 2009 08:52:23 +0000

[...] (re-)reading. And on the topic of deferred lighting, Adrian Bentley talks about the (non-)use of stenciling to accelerate same. Lastly, Adrian Stone makes an argument for deferred shading and against [...]

Comment on My voice is my Passport, verify me by Devin Christensen

Devin Christensen — Fri, 05 Jun 2009 01:26:46 +0000

Sneakers!

Comment on Parallelismorama by adruab

adruab — Tue, 13 Jan 2009 07:01:16 +0000

Cool, though you’re probably not interested in me discussing parallelism .

Comment on Parallelismorama by Esther

Esther — Tue, 13 Jan 2009 00:14:41 +0000

I’m in Seattle every weekend lately. We should hang out!:-)

Comment on Horrible acronym for very refreshing RPG by adruab

adruab — Sat, 12 Jul 2008 19:08:12 +0000

I did not see it, but cool! Alas I think we are booked on the 19th (like x3). The current winner is family reunion to attend. Sorry!

Comment on Horrible acronym for very refreshing RPG by Esther

Esther — Tue, 24 Jun 2008 07:36:06 +0000

On an entirely different note, did you happen to see this post:
http://katecrust.livejournal.com/227209.html

It could be a tradition! It’s one of the few reasons I go to Seattle anymore.

Also, I have anime DVDs to return to you. So there were two entirely different notes

Comment on Weee… Time Machine by adruab

adruab — Wed, 14 Nov 2007 00:55:29 +0000

Nope nope . Actually I think your Thousand Young performance I went to was after burlesque night. Ooh, DVDs! I swear they are kind of like crack. I look forward to when ever this new performance is.