POV-Ray : Newsgroups : irtc.animations : Looks like a real round this time : Re: Looks like a real round this time Server Time
24 Mar 2023 14:43:56 EDT (-0400)
  Re: Looks like a real round this time  
From: Markus Altendorff
Date: 19 Jan 2007 18:10:34
Message: <45b14fea@news.povray.org>
dbott wrote:
> A great book is Beginning Math and Physics for Game
> Programmers...by Wendy Stahler. You don't have to a
> Astrophysicist to understand it. I'm a newbe, but I will
> start competing regularly. This is my third animation I've completed and I
> seem to getting better with each one.
> But I guess you'll be the judge of  that. ()^()...........

We'd all like to, i guess (to the admins: hint, hint, nudge, 
nudge ;)

> dbott
> "i_need_a_unique_name" <ine### [at] gmailcom> wrote in message
> news:web.45b0e6a648a177e0c3e0e7940@news.povray.org...
>>> Yuck. Ewww. I did that hideous stuff, and it's OUT IN PUBLIC? Uh oh...
> ;)
>> Bet mines more yucky than yours.
>> So what was on your reading list? I think I'm sorley in need of some
>> education (especially regards to 3D maths).

Uh, sorry, i'm more of the mouse-pushing type, and less 
competent when it comes to the actual math behind it... 
(though i once wrote a 3-D drawing routine on my ZX Spectrum 
48 kByte, and a spinning 3-D map for a never-to-be 
roleplaying game on my Amiga 2000 - am i a fossil or what? ;)

Well, a book that really inspired was Arndt von 
Koenigsmarck's "Femme Digitale" (Addison-Wesley), though 
i've not even started yet to build more of his sculpting 
hints into my models - except for the design guides to build 
eyes from separate layers instead of textured sphere 
primitives. It's geared towards the 
Maya/3Ds/Cinema/Blender/etc. users, though, not those that 
enjoy coding by TextPad ;)
At least i've learned that mixing triangles and quads in a 
mesh isn't the brightest thing to do, and that there's much 
to learn when shaping hands and feet :)

There's another one, sneakily also called "Femme Digitale", 
by Michael Burns. I'd NOT recommend that one, because it's 
trying to do too much in too little space. Nice pictures, 
nice screenshots, but - trying to explaind modelling AND 
texturing of a complete human figure on six pages doesn't 
really teach you anything. It covers everything and then 
some, from Photoshop to Poser to Max to Featured Artists, 
but it doesn't do anything really in depth. Where AvK takes 
a dozen pages for the do's and dont's of the fingers alone, 
with MB it's more like "hey, pick a Poser preset, run 
Photoshop across and be done with it." I was lucky as it was 
on sale when i ordered it at a well-known internet book 
retailer whose name vaguely reminds of a tropical river ;), 
because i wouldn't spend more than the 5 $ on it - if i want 
pictures to make me green with envy, i'd get a high-gloss 
Royo, Sorayama or Vallejo collection for 9,95 $ ;)

The other was Koenigsmark's "Cinema 4D v.9" workshop book 
(published by Addison-Wesley, too), which i got for an 
incredible 3 Euros at an electronics store (with v.10 out, 
they were clearing their stock), without which i wouldn't 
have started to save time by animating using "intelligent" 
objects (like e.g. mechanical devices that are operated by a 
single keyframed input which internally calculates/affects 
various angles/positions - i've built a robot arm that has 
an attached user data slider which not only opens/closes the 
"fingers" but also drives the angle of the corresponding 
worm gear in a convincing manner; a four-layer door with 
bolts that makes use of a similar logic, and warning beacons 
spinning and flashing all by themselves (and a timer) ;)

Also, this time, the arms of my humanoid models don't use 
inverse kinematics for positioning, but instead a set of 
multiple 2-axis remote-control input boxes cross-connected 
to multiple bones, including mapping input/output values to 
avoid unnatural poses:
- Shoulder X/Y translates the angle of the shoulder bone
- Upper Arm X/Y has "up/down +/- 100 degrees" on the Y axis, 
and "forward/back +/- 100 degrees" on the X axis
- Lower Arm X/Y has "Heading Straight 0 / folded on + 170" 
for the Lower Arm on the X, and "Rotate Upper Arm Bone +/- 
90 degrees" on the Y axis
- Hand X/Y has a wiring to the Tilt and Roll of the hand 
bone, instead of the heading/tilt.

When i animate, i animate the controllers instead of the 
actual bones, which looks a bit different compared to 
keyframing the bones' angles themselves, but the tweening is 
less artificial than IK can sometimes be.

There are a few "broken by design" points i still need to 
address, like the problem of the upper arm mesh rolling at 
the shoulder joint (it shouldn't, because the twist of 
tissue extends across the whole upper arm - need to create a 
chain of "helper bones" that maintain the shoulder at null 
twist and accumulate the twist down the upper arm). Another 
mess is that once the arm tilt approaches 90 degrees (arm 
down/up), the result of heading and roll axis collapse into 
one. A null bone for the heading/tilt, and an additional one 
for the roll would solve that.
And don't get me started about the hip bone, which i failed 
to de-couple from the standard orientation, so any swaying 
left/right runs through a 0/360 border - it's OK if you 
keyframe it, but once you decide to re-work the motion 
curves, it tends to do lower-back-breaking because the any 
little shifting of H/P/R angles wreaks havoc on the 

>> Why is it that the IRTC animation comp always seems so under-entered but
> the
>> stills typically has loads of entries?

Well, unless you're doing an incredibly detailed still 
scene, animating may be even more time-consuming than 
building a still picture? (did i write that out loud? 
Ooops... anyone from the stills crowd here? Nobody? Whew... ;)


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