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Unlimited Detail Technology

category: offtopic [glöplog]
thanks for the advice chaps - how do I post a image here - i'll post a screen shot so u can see the problem
added on the 2010-04-16 16:08:36 by ZJ ZJ
BB Image


thats using the simple code on the previous pages - u can see the forshortening problem.
added on the 2010-04-16 16:17:34 by ZJ ZJ
I found something for you. Look at this document
WarpEngine

If I will find some free time, I will try implement it - it looks very simple.

I think that it could be good technology for static locations.
added on the 2010-04-17 15:38:29 by krzyzan krzyzan
awesome - just reading it now - thanks man
added on the 2010-04-17 17:51:03 by ZJ ZJ
cool article - maybe thats a solution to the overdraw issue


create 3 depth maps from the octree using the nearest 3 visible surfaces

and then image warp for your final image - it's almost like shadow mapping e.t.c..
added on the 2010-04-17 18:18:24 by ZJ ZJ
had a "great Idea" lol

the perspective problem is a right pain - u need the Z.

But with four 2D points u can find the perspective center quite easily by simply drawing the diagonals - the perspective center is where the lines cross. This of course needs a divide to solve the intersection (might be a short cut to exploit the fact the 2d points are square - too lazy to figure this out). So I was thinking - maybe some sort of software hologram? - 2 sets of visual 2D info combine to make a 3d image ? the octree has all the info - just gotta work out how to make the 2 sets of data.
added on the 2010-04-19 20:23:41 by ZJ ZJ
Why are you so afraid of divides?
added on the 2010-04-19 20:32:38 by kusma kusma
engine coder mate - divides/if statments give me the willies!
added on the 2010-04-19 20:34:51 by ZJ ZJ
what's wrong with if?
conitionals are generally bad (maybe on a risc the're ok is small doses - conitional execution e.t.c)

modern PC's are pretty good at handling conditionals - but u still don't want them in your tight low level loops

branch prediction on the x and ps3 is broken - if's e.t.c.
and a L2 cache miss is 500-600 cycles

the 2 things combined are baaad :P

u can get around it by hand coding - but it's a pain.
added on the 2010-04-19 21:21:20 by ZJ ZJ
whynot2000: 'if' sends me to branching hell on the GPU if administered in lethal doses.
added on the 2010-04-19 21:23:17 by decipher decipher
Yes, the diagonals are lines in both world and screen space, so the point where they intersect is perspective correct. But it only applies to the centre of each square. I can't see how it helps you split the edges.

You're right about conditional code, of course. It's usually best to avoid it even if you get a bunch of multiplications by 1 and that sort of thing. But divisions really aren't that bad, especially with pairing and pipelining and all that.
added on the 2010-04-19 21:51:17 by doomdoom doomdoom
yup it doesn't help finding the edges - it just put me into the line of thinking that the 2 2d lines combined give u 3d info. thus extending that fully - 2 sets of 2d info - to create the 3d image - ala software hologram type thing. Dunno if it's doable - in fact I don't even know where to start, just thought it was interesting as crazy as it sounds :)
added on the 2010-04-19 21:57:49 by ZJ ZJ
Jim Blinn - Inferring Transforms (buy it there or warez it somewhere else ;)

There's a routine at the end that converts four screen space points into a 3x3 matrix for getting perspective correct homogenous coordinates (x,y,w). Works out of the box (used it for some art projection stuff on non-orthogonal surfaces), no divs/ifs, and all your perspective and edge finding problems are solved. :)


added on the 2010-04-19 22:32:34 by kb_ kb_
sweet thanks dood

found this too:

http://digital.library.adelaide.edu.au/dspace/bitstream/2440/48497/3/02chapters1-5.pdf
added on the 2010-04-19 22:41:17 by ZJ ZJ
ZJ: If divisions give you the willies BECAUSE you're an engine-coder, you should find a different discipline. Seriously.
added on the 2010-04-19 23:12:03 by kusma kusma
hehe thanks for the advice kusma :) but i'll stick to it all the same
added on the 2010-04-19 23:16:16 by ZJ ZJ
3D from 2D Point Correspondences:
Fundamental Matrix
added on the 2010-04-20 08:55:50 by Teehase Teehase
http://www.youtube.com/watch?feature=player_embedded&v=Irf-HJ4fBls
added on the 2013-05-25 22:04:08 by calimero calimero
:O
O_______________________________o;
added on the 2013-05-25 22:29:32 by mog mog
another demo from unlimited delayed technology?
added on the 2013-05-25 22:48:15 by swapd0 swapd0
Okay, the video is pretty convincing. Now give me an exe.
added on the 2013-05-25 22:52:57 by Preacher Preacher
it's nice :)
i wonder how much TBs/PBs those datasets are tho :)
Quote:
Okay, the video is pretty convincing


I thought the video was laughably unconvincing personally, he's got to be the worst salesman ever :D The bit where he says they're a group of scientists picking the hardest problems out there and taking them down one by one, hilarious!

The tech on the other hand looks pretty convincing. The bit that does really get me though is the disk access. If you have say a 1TB data set, and you're viewing at say 1 megapixel res, even at best case you're asking for say 3 million bytes from disk. Per frame, so multiply that by at least 10. And those bytes can come from potentially anywhere on the disk. It's going to need a very fast 1TB+ SSD. Yet they show it running well over USB 2 or a network.
added on the 2013-05-25 23:19:03 by psonice psonice

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