IRC log for #brlcad on 20070614

00:29.48 *** join/#brlcad rga (n=rga@unaffiliated/rga)
00:31.11 *** part/#brlcad rga (n=rga@unaffiliated/rga)
01:10.59 *** join/#brlcad poolio (n=poolio@c-69-251-3-107.hsd1.md.comcast.net)
01:19.40 *** join/#brlcad IriX64 (n=mario_du@bas2-sudbury98-1177726794.dsl.bell.ca)
01:32.03 IriX64 thats going to set me back, another 17" monitor gone
05:36.12 *** join/#brlcad ibot (n=ibot@pdpc/supporter/active/TimRiker/bot/apt)
05:36.12 *** topic/#brlcad is BRL-CAD Open Source Solid Modeling || http://brlcad.org || http://sf.net/projects/brlcad || http://fisheye1.cenqua.com/browse/brlcad/brlcad || 7.10 is now released! .. e-mail announcements will follow posting of binary distributions
05:37.16 *** join/#brlcad ibot (n=ibot@pdpc/supporter/active/TimRiker/bot/apt)
05:37.16 *** topic/#brlcad is BRL-CAD Open Source Solid Modeling || http://brlcad.org || http://sf.net/projects/brlcad || http://fisheye1.cenqua.com/browse/brlcad/brlcad || 7.10 is now released! .. e-mail announcements will follow posting of binary distributions
07:21.00 *** join/#brlcad Laniakea (n=clock@zux221-122-143.adsl.green.ch)
08:32.09 *** join/#brlcad CIA-4 (n=CIA@208.69.182.149)
09:56.43 *** join/#brlcad ibot_ (i=ibot@pdpc/supporter/active/TimRiker/bot/apt)
09:56.43 *** topic/#brlcad is BRL-CAD Open Source Solid Modeling || http://brlcad.org || http://sf.net/projects/brlcad || http://fisheye1.cenqua.com/browse/brlcad/brlcad || 7.10 is now released! .. e-mail announcements will follow posting of binary distributions
14:00.29 *** join/#brlcad cad56 (n=92500941@bz.bzflag.bz)
14:18.44 *** join/#brlcad poolio (n=poolio@c-69-251-3-107.hsd1.md.comcast.net)
14:52.49 *** join/#brlcad elite01 (n=elite01@dslc-082-082-073-250.pools.arcor-ip.net)
15:48.15 *** join/#brlcad elite01_ (n=elite01@dslc-082-082-082-130.pools.arcor-ip.net)
16:08.46 *** join/#brlcad elite01_ (n=elite01@dslc-082-082-082-130.pools.arcor-ip.net)
17:16.50 *** join/#brlcad ibot (i=ibot@pdpc/supporter/active/TimRiker/bot/apt)
17:16.50 *** topic/#brlcad is BRL-CAD Open Source Solid Modeling || http://brlcad.org || http://sf.net/projects/brlcad || http://fisheye1.cenqua.com/browse/brlcad/brlcad || 7.10 is now released! .. e-mail announcements will follow posting of binary distributions
17:23.05 *** join/#brlcad ibot_ (i=ibot@pdpc/supporter/active/TimRiker/bot/apt)
17:23.05 *** topic/#brlcad is BRL-CAD Open Source Solid Modeling || http://brlcad.org || http://sf.net/projects/brlcad || http://fisheye1.cenqua.com/browse/brlcad/brlcad || 7.10 is now released! .. e-mail announcements will follow posting of binary distributions
17:34.02 *** join/#brlcad ibot (i=ibot@rikers.org)
17:34.02 *** topic/#brlcad is BRL-CAD Open Source Solid Modeling || http://brlcad.org || http://sf.net/projects/brlcad || http://fisheye1.cenqua.com/browse/brlcad/brlcad || 7.10 is now released! .. e-mail announcements will follow posting of binary distributions
17:52.58 *** join/#brlcad CIA-4 (n=CIA@208.69.182.149)
18:06.20 *** join/#brlcad CIA-4 (i=cia@208.69.182.149)
18:10.39 IriX64 http://www.pastebin.ca/566929 can't remember if i showed you this warning before or not.
18:30.41 IriX64 also wonders what on earth -lGL is doing in there when i specified no gl and the summary said it was not enabled.
18:31.43 IriX64 .
18:34.21 IriX64 http://www.pastebin.ca/566971 <--- in case you think I jest.
18:39.11 *** join/#brlcad Elperion (n=Bary@p548764FD.dip.t-dialin.net)
18:40.59 IriX64 huh it split it again, the paste i mean
18:41.13 IriX64 some near top some near bottom
18:41.47 IriX64 line 10
18:52.00 *** join/#brlcad poolio (n=poolio@c-69-251-3-107.hsd1.md.comcast.net)
19:11.01 brlcad IriX64: tone it down
19:12.15 brlcad that -lGL is coming from tcl, something in their configure
19:12.28 brlcad looks like their X11 tests
19:13.19 IriX64 never thought of that thanks
19:13.31 IriX64 and i will
19:16.41 poolio brlcad: Is there already an established voxel data spec?
19:40.22 *** join/#brlcad yukonbob (n=bch@whthyt224-180.northwestel.net)
20:06.15 IriX64 http://www.terarecon.com/downloads/support/vp1000_voxelfileformat.pdf poolio
20:08.25 brlcad poolio: brl-cad uses raw data for most of the geometry data sets as there are a slew of other tools for processing raw data in a streaming manner among other manipulations
20:08.48 brlcad so if you were to create a vol primitive, for example, you'd provide raw b&w slices
20:09.56 brlcad the mk_vol() routine will take volumetric data in said raw format and make a vol for you
20:10.11 brlcad mk_vol(struct rt_wdb *fp, const char *name, const char *file, int xdim, int ydim, int zdim, int lo, int hi, const fastf_t *cellsize, const matp_t mat)
20:14.40 ``Erik hm, 15 minutes, I wonder if this test run will be done by then.
20:17.17 *** join/#brlcad Obscene_CNN (n=DiscoBan@owt-64-146-239-67.owt.com)
20:17.29 *** part/#brlcad Obscene_CNN (n=DiscoBan@owt-64-146-239-67.owt.com)
20:27.12 poolio brlcad: thanks
20:28.03 poolio brlcad: so support for volumetric data/voxels is already builtin?
20:58.04 *** join/#brlcad Laniakea (i=clock@77-56-101-172.dclient.hispeed.ch)
20:59.41 IriX64 brlcad: I can't seem to get anybody's windows x-server (besides cygwin-x) to have the geometry window pull double duty as the framebuffer, is it too much of a hassle to type exec fbserv -S690 /dev/X and use that for rendering?
21:01.16 brlcad poolio: yes, there is a volumetric primitive (the 'vol' primitive) -- i'd suggest making one by hand either in mged or in code using mk_vol() to get familiar
21:01.48 Laniakea brlcad: tell me - what determines the positions are which photons will fall on emulsion?
21:01.54 brlcad IriX64: that's a known issue with the Windows display manager
21:01.57 Laniakea Not the density, but the individual positions themselves?
21:02.22 IriX64 really, thought it was my fault, sorry to have brought it up
21:02.55 brlcad Laniakea: what do you mean by the positions? the photons are fired out from the light sources randomly .. hit points are determined against the geometry, which in turn deposits the photons
21:04.05 Laniakea brlcad: if you have a coherent source (laser), you still get random positions.
21:04.28 Laniakea Coherent source has a very simple wavefunction - sine wave - that doesn't contain any randomness
21:04.34 Laniakea Where does the entropy come from?
21:05.17 brlcad Laniakea: er, I presumed you were talking about photon mapping
21:05.32 brlcad do you just mean regular ray-tracing photons?
21:06.17 brlcad because photon mapping that I just described is something very different
21:07.22 brlcad regular ray-tracing fires a grid of rays that recursive traverse through a scene, forking off diffusion, reflection, and perhaps shador rays for each segment
21:08.05 brlcad you can tell rt to shoot perfectly in the center of the grid cells (the default), or jitter the rays, or shoot multiple per cell, or shoot multiple per cell jittered, etc
21:16.47 yukonbob brlcad: do you have any info on the headers of .dems? The stuff I was dealing with before was always "square" (ie: X by Y) size, but the samples you sent have variable numbers of entries per record, and I'm not sure how to interpret it...
21:17.12 brlcad howdy yukonbob
21:17.25 brlcad hm, mebbie
21:17.33 yukonbob *"headers" where header == first 1024-byte block, and 9-pieces of info at start of ea. record.
21:18.12 yukonbob I've googled around, and skimmed other projects, but nothings turned up for me yet...
21:21.18 brlcad http://rockyweb.cr.usgs.gov/nmpstds/demstds.html
21:21.35 brlcad part 2 covers the format
21:22.06 Laniakea brlcad: no I mean the physical workings of our universe
21:24.19 yukonbob brlcad: rock'n'roll... thx
21:28.05 ``Erik ahhhhhh, home at last
22:03.10 *** join/#brlcad jimmyz (n=asd@host81-129-128-152.range81-129.btcentralplus.com)
22:04.33 jimmyz hi
22:14.40 brlcad howdy jimmyz
22:15.05 CIA-4 BRL-CAD: 03jlowenz * 10brlcad/src/conv/iges/BrepHandler.cpp: When an arc's start center and end points are coplanar, we can't find the plane! so calculate the normal and pass it through to the handler...
22:16.39 CIA-4 BRL-CAD: 03jlowenz * 10brlcad/src/conv/iges/brlcad.hpp: alter the arc handle method to take a pre-calculated normal
22:17.27 jimmyz hi brlcad
22:17.30 jimmyz are you a bot?
22:17.59 brlcad jimmyz: are you?
22:18.09 jimmyz corse not
22:18.23 CIA-4 BRL-CAD: 03jlowenz * 10brlcad/src/conv/iges/brlcad_brep.cpp: to avoid trying to build a plane from a line, pass the origin and a normal instead
22:18.24 brlcad then corse not too
22:18.33 jimmyz ok sorry
22:18.46 jimmyz i'm interested in learning cad?
22:18.55 jimmyz this a good place to start?
22:19.09 brlcad as good a place as any
22:19.20 jimmyz do you know catia at all/
22:19.31 brlcad depends for what purpose, but most of the fundamentals cut across industries
22:19.37 CIA-4 BRL-CAD: 03jlowenz * 10brlcad/src/conv/iges/n_iges.hpp: fix circular arc handler method to take a normal
22:19.40 brlcad the basics of catia, yes
22:19.56 jimmyz how much is it?
22:20.10 brlcad brl-cad's gui interface (mged) is nothing at all like catia ;)
22:20.20 brlcad you'd have to ask the catia folks
22:20.27 jimmyz how capable is brl cad?
22:20.42 brlcad fully capable for what it's intended, it's in production use
22:20.43 jimmyz cf solidworks and catia etc
22:20.59 jimmyz does it do FEA?
22:21.05 brlcad but we don't do everything, and don't cater to entire sub-industries of CAD (see the docs on the website)
22:21.27 CIA-4 BRL-CAD: 03jlowenz * 10brlcad/src/conv/iges/nmain.cpp: add a cheesy file parameter to converter (remove hard-coded filename)... needs to be fleshed out better
22:21.57 brlcad ehm, most "CAD" packages don't do actual finite element analysis -- they interface with them or include a separate analysis module
22:22.18 jimmyz oh i see
22:22.28 jimmyz are you in the industry?
22:22.45 brlcad there is a brl-cad interface to fea, several actually -- some better than others, some under active development
22:23.00 brlcad er, I have no idea what you mean by that
22:23.10 jimmyz do you do cad for a living
22:23.14 brlcad what constitutes being "in the industry"
22:23.45 brlcad are you asking if am I am a geometric designer/modeler?
22:24.08 CIA-4 BRL-CAD: 03jlowenz * 10brlcad/src/librt/opennurbs_ext.cpp: many bug fixes (openNURBS knot vector problem again...) lots of debug statements. adjusted flatness criterion to be a scale of the curve length.
22:24.23 jimmyz umm guess so
22:24.28 brlcad i have modeled some things, but i'm more a developer -- software architect, programmer, code monkey
22:24.41 jimmyz oh right
22:25.10 brlcad i work on brl-cad .. a lot .. among other hats
22:25.25 jimmyz is it still developed by the military?
22:25.36 brlcad yes, actively developed and used
22:25.57 jimmyz i see
22:26.17 jimmyz i'm in UK btw
22:27.41 CIA-4 BRL-CAD: 03jlowenz * 10brlcad/src/other/openNURBS/opennurbs_bezier.cpp: fixed convex hull handling and finished case C implementation (not debugged yet)
22:28.49 CIA-4 BRL-CAD: 03jlowenz * 10brlcad/src/other/openNURBS/opennurbs_curve.h: NumIntersectionsWith now virtual (duh)
22:29.11 jimmyz what is CIA 4 saying?
22:29.29 brlcad those are changes being made to the source code
22:29.40 brlcad cia announces them in real-time as the code is modified
22:29.49 jimmyz who's jlowenz?
22:30.04 brlcad one of the developers
22:30.11 jimmyz oh i see
22:30.58 jimmyz do these cad programs generate output files for CNC machines to work on?
22:55.04 *** join/#brlcad poolio (n=poolio@c-69-251-3-107.hsd1.md.comcast.net)
23:05.55 brlcad jimmyz: not usually
23:05.59 brlcad that's what CAM software is for
23:06.31 brlcad e.g. GNU CAM: http://gcam.js.cx/index.php/Main_Page
23:06.39 ``Erik we can generate stl, but not gcode
23:07.30 brlcad someone should write a g-gcode
23:12.17 *** join/#brlcad louipc (n=louipc@bas8-toronto63-1096782753.dsl.bell.ca)
23:16.27 bjorkBSD brlcad, doesn't the .mil rely on sub-contractors?
23:19.50 *** join/#brlcad Twingy (n=justin@74.92.144.217)
23:33.27 brlcad bjorkBSD: huh?
23:33.32 brlcad sometimes
23:33.45 bjorkBSD i'm wondering how they'd use brl-cad at all.
23:34.00 brlcad er, how's that?
23:34.05 brlcad or rather why's that?
23:34.21 bjorkBSD if they're using subcontractors, they only need to specify an order no?
23:34.46 bjorkBSD 'build me a tank daggammit'
23:34.51 bjorkBSD and then tank get's built.
23:34.57 brlcad oh
23:34.59 brlcad heck no
23:34.59 bjorkBSD then .mil takes delivery :)
23:35.21 *** part/#brlcad jimmyz (n=asd@host81-129-128-152.range81-129.btcentralplus.com)
23:35.49 *** join/#brlcad jimmyz (n=asd@host81-129-128-152.range81-129.btcentralplus.com)
23:36.05 brlcad the tanks are modeled by the modeling experts (of which there are contractor and gov't experts that are adept in brl-cad)
23:36.10 louipc I bet they like to be involved with the design too :D
23:36.18 brlcad also, subcontractor != contractor
23:36.29 brlcad i think you just mean contractors
23:36.53 *** part/#brlcad jimmyz (n=asd@host81-129-128-152.range81-129.btcentralplus.com)
23:36.54 brlcad a subcontractor would be someone working under contract to a contractor
23:37.32 louipc subcontractors might not even know what machine the part they're making goes in...
23:38.21 bjorkBSD ah i see i see.
23:38.31 bjorkBSD just like ... construction!
23:38.41 brlcad bjorkBSD: brl-cad is primarly used to model military assets for analysis purposes
23:38.48 brlcad emphasis on the analysis aspect
23:38.55 bjorkBSD hmmm.
23:39.06 brlcad like, model the M1A1 and analyze how well it does in a given encounter
23:39.20 bjorkBSD huh? in a combat situation?
23:39.24 brlcad sure
23:39.28 bjorkBSD you can do THAT?!
23:39.40 brlcad that's what it's *primarily* used for
23:39.56 bjorkBSD shit! we've been abusing the poor thing by making tea cups with it then :-S
23:40.12 brlcad there is a brl-cad model of almost every military asset that's been in production over the past two decades
23:40.26 bjorkBSD damn!
23:40.27 brlcad at least army and air force.. navy not so much, but some
23:40.55 bjorkBSD that's pretty cool.
23:41.05 bjorkBSD i'm a pacifist of course...
23:41.16 brlcad some modeled entirely by hand, some modeled in other systems and converted to brl-cad, some worked on in multiple cad systems by many groups, etc
23:41.17 bjorkBSD but that's still pretty damned cool :-?
23:42.22 bjorkBSD hmmm.
23:42.23 brlcad many of the folks that do the analyses are pacificists too -- vulnerability is generally more important than lethality
23:42.38 brlcad keeping the folks inside the vehicles safe
23:42.47 bjorkBSD yes. the embedded journalists :)
23:42.53 brlcad and how to do that better
23:42.59 bjorkBSD we don't want to wake those up in the middle of something fun :D
23:43.30 bjorkBSD so you're saying there's a strength of materials component hidden in brl-cad?
23:44.09 brlcad wasn't referring to the 'pacifist' folks inside the vehicle .. was referring to people that run the analyses and simulations, trying to find ways to make the vehicles more safe
23:44.19 bjorkBSD i know i was being 'punny'.
23:44.22 brlcad bjorkBSD: no, i'm not saying that
23:44.58 brlcad brl-cad does the geometric representation, physical characteristics -- representing what exists in real life on the computer
23:45.11 brlcad it's the job of various analysis codes to do something with that information
23:45.36 brlcad whether it has anything to do with material strengths, penetration equations, system connectivity, etc
23:45.46 bjorkBSD aha
23:46.07 brlcad brl-cad just answers the fundamental geometry questions
23:48.18 bjorkBSD heh. i wonder what they used in ussr way back when for the same tasks.
23:49.32 brlcad the extent of brl-cad's analysis capacity are those that purely relate to geometric analysis -- computing weights, moments, presented area, energy signatures, images, etc
23:50.28 brlcad once we start talking about penetration and material interactions, things get sensitive or classified really quick
23:50.43 bjorkBSD that's understandable.
23:50.46 brlcad and they certainly wouldn't just be sitting there in an open souce package :)
23:51.35 brlcad it was hard enough to open source brl-cad given it's mere ties to the analysis
23:52.36 brlcad even with 15 years of "almost open source" public distribution
23:52.43 bjorkBSD hmmm.
23:52.50 bjorkBSD paranoid much? :D
23:53.35 brlcad not me, but others .. heh :)
23:54.59 bjorkBSD so why were the sources opened then?
23:55.30 bjorkBSD given the importance of the tool.

Generated by irclog2html.pl Modified by Tim Riker to work with infobot.