reorient center to best fit of BBOX?

Mailing List

Home

Forum Home

Softimage

Carrara

trueSpace

Dir3d-l

Maya - a powerful 3D animation and visual effects software

Macromedia Flash Development

Subjects

•	Cameras
•	scaleDown command
•	black out solved
•	Aircraft Tutorial
•	Mathematical XYZ ?
•	Its done This vs That
•	Its done first week
•	recommendations for screen video captures?
•	3DExplorer "Oddity "
•	New Director
•	ProTeam renewals
•	Fuel 's new websites (X post)
•	Blue peter create a make toy
•	targeting groups question
•	XPost: Shockwave 3D game ( sort of )
•	RES: RES: RES: Fish Modeling
•	Emitting particles from object intersection
•	Fuel 's new websites (X post)
•	Texturing
•	Big Break Contest Videos
•	New Plugins
•	Models and Texture on my updated site
•	Error Installing Patch tS6 6
•	Plasma?
•	Looking for Inspiration
•	Weird EMail Q
•	It 's done first week ?
•	Cherry not cranberry
•	New game
•	Camera Animation Problem
•	Particle plugins?

reorient center to best fit of BBOX?

reorient center to best fit of BBOX?

2004-05-07 - By Raffaele "ThE_JacO" Fragapane

Back

Reply: 1 2 3

If you have (or feel like buying it) mathematics for 3D games programming
and computer graphics there’s a good half a chapter about bounding volumes,
also in there you can find a really good explanation of the “best fitting
bounding box” maths.

It shouldn’t be too hard to implement, but I don’t have the book here, will
have a look into it tonight or tomorrow night if you want.

Also a look around on game coding sites should return enough solution.

Figuring out ideal bounding boxes in the least expensive possible way is
something fairly common in the 3Dgames maths scenario.

-~== Raffaele Fragapane ==~-
-~== Freelance Technical Animator & TD ==~-
-~== Senior Technical Animator @ Peerless Camera ==~-

- Currently London Based
- +44 798 4955734

__ __

From: owner-xsi@(protected) [mailto:owner-xsi@(protected)] On Behalf Of
Graham D Clark
Sent: Friday, May 07, 2004 6:42 PM
To: xsi@(protected)
Subject: [Script]reorient center to best fit of BBOX?

Any suggestion for how to reorient center of object to best BBOX fit?
Ie if an elongated cubes points are rotated, center remains, then its
frozen, getting the center orientation back so that the BBOX would be the
same as the elongated cubes? (preferabley with y pointing in longest
direction of mesh)

Ie2 if a cylinders center is moved away and reorinted, and frozen, a way to
return the center as close as possible to the orginal orientation?

To see my issue quickly:
-get cube,
-put display in BBOX
-Rotate it
-freeze it
Now try to get the center orientation back via script.

I can do it manually with ref edges but I have many many objects with
centers way off and edgeloops commands are not yet exposed in any version of
XSI.

Perhaps first I need to move center to average vertices, and perhaps use
edge looping no corners, get top 20 % longest continuos edge loops,
collecting the end points and using the average vector as y orientation, or
perhaps reorienting a BBOX scaling in to mesh surface by checking for points
outside the BBOX, and reorinting until best fit...

Anyways these ideas seem kind of lame. Anyone have a suggestion? Is there an
easier way using basic XSI commands?

Thank you, Graham
-- ---- ---- ---- ---- ---- --
HYPERLINK "http://www.grahamdclark.com"http://www.grahamdclark.com
2nd hand TD

---
Incoming mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.638 / Virus Database: 409 - Release Date: 21-Mar-04 (See http://Mar-04.ora-code.com)

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.638 / Virus Database: 409 - Release Date: 21-Mar-04 (See http://Mar-04.ora-code.com)

<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft
-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns="http:
//www.w3.org/TR/REC-html40">

<head>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=Windows-1252 (See http://ows-1252.ora-code.com)">

<meta name=Generator content="Microsoft Word 11 (filtered medium)">

<title>[Script]reorient center to best fit of BBOX?</title>
<style>

</style>

</head>

<body lang=EN-US link=blue vlink=blue>

<div class=Section1>

If you have (or feel like buying it)
mathematics for 3D games programming and computer graphics there’s a good
half
a chapter about bounding volumes, also in there you can find a really good
explanation of the “best fitting bounding box” maths.<o:p></o:p>

It shouldn’t be too hard to
implement, but
I don’t have the book here, will have a look into it tonight or tomorrow
night
if you want.<o:p></o:p>

<o:p> </o:p>

Also a look around on game coding sites
should return enough solution.<o:p></o:p>

Figuring out ideal bounding boxes in the
least expensive possible way is something fairly common in the 3Dgames maths
scenario.<o:p></o:p>

<o:p> </o:p>

<div>

          
         
-~== Raffaele Fragapane ==~- 
        -~==
Freelance Technical Animator & TD ==~- 
-~== Senior Technical Animator @ Peerless Camera
==~- <o:p></o:p>


- Currently London Based 
- +44 798 4955734 <o:p></o:p>

</div>

<div>

<div class=MsoNormal align=center style='margin-left:36.0pt;text-align:center'>


<hr size=2 width="100%" align=center tabindex=-1>

</div>

From:
owner-xsi@(protected) [mailto:owner-xsi@(protected)] On Behalf Of Graham D Clark 
Sent: Friday, May 07, 2004 6:42 PM
 
To: xsi@(protected) 
Subject: [Script]reorient center
to best fit of BBOX?<o:p></o:p>

</div>

<o:p> </o:p>

<o:p> </o:p>

Any suggestion for how to reorient center of object
to best BBOX fit? 
Ie if
an elongated cubes points are rotated, center remains, then its frozen, getting
the center orientation back so that the BBOX would be the same as the elongated
cubes? (preferabley with y pointing in longest direction of mesh)
<o:p></o:p>

Ie2 if a cylinders center is moved away and
reorinted, and frozen, a way to return the center as close as possible to the
orginal orientation?<o:p></o:p>

To see my issue quickly: 
-get
cube, 
-put
display in BBOX 
-Rotate
it 
-freeze
it 
Now
try to get the center orientation back via script. <o:p></o:p>

I can do it manually with ref edges but I have many
many objects with centers way off and edgeloops commands are not yet exposed in
any version of XSI.<o:p></o:p>

Perhaps first I need to move center to average
vertices, and perhaps use edge looping no corners, get top 20 % longest
continuos edge loops, collecting the end points and using the average vector as
y orientation, or perhaps reorienting a BBOX scaling in to mesh surface by
checking for points outside the BBOX, and reorinting until best fit... <o:p></o:p>

Anyways these ideas seem kind of lame. Anyone have a
suggestion? Is there an easier way using basic XSI commands? <o:p
></o:p>

Thank you, Graham 
-- ---- ---- ---- ---- ---- -- 
<a href="http://www.grahamdclark.com">http://www.grahamdclark.com</a> 
2nd hand TD <o:p></o:p>

<o:p> </o:p>

</div>

</body>

</html>
 

--- 
Incoming mail is certified Virus Free. 
Checked by AVG anti-virus system (http://www.grisoft.com). 
Version: 6.0.638 / Virus Database: 409 - Release Date: 21-Mar-04 (See http://Mar-04.ora-code.com) 
 

--- 
Outgoing mail is certified Virus Free. 
Checked by AVG anti-virus system (http://www.grisoft.com). 
Version: 6.0.638 / Virus Database: 409 - Release Date: 21-Mar-04 (See http://Mar-04.ora-code.com)