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[Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html
From: |
Benja Fallenstein |
Subject: |
[Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html |
Date: |
Fri, 30 Aug 2002 10:44:21 -0400 |
CVSROOT: /cvsroot/gzz
Module name: gzz
Changes by: Benja Fallenstein <address@hidden> 02/08/30 10:44:21
Modified files:
doc/pegboard/1003: PEG_1003.html
Log message:
Comment
CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/doc/pegboard/1003/PEG_1003.html.diff?tr1=1.9&tr2=1.10&r1=text&r2=text
Patches:
Index: gzz/doc/pegboard/1003/PEG_1003.html
diff -c gzz/doc/pegboard/1003/PEG_1003.html:1.9
gzz/doc/pegboard/1003/PEG_1003.html:1.10
*** gzz/doc/pegboard/1003/PEG_1003.html:1.9 Fri Aug 30 09:10:17 2002
--- gzz/doc/pegboard/1003/PEG_1003.html Fri Aug 30 10:44:21 2002
***************
*** 11,42 ****
<p>Open issues:<br>
</p>
!
<ul>
<li>Is the integer identifier of the coordinate system into which to
place a new coordinate system appropriate?</li>
<li>Should plain coordinate systems be usable as those ints?
<small>(Benja:) "Plain coordinate systems"?</small></li>
!
<ul>
<li>What are the semantics there? Current, just translate, is not good.
However, using the vob-internal CS is not really nice either, as Vob CSs
usually are in pixels, and this would be in 10s or 100s of pixels per
unit.</li>
!
</ul>
<li>The most general use case is the PP-like viewport. How is that
implemented?
You need</li>
!
<ul>
<li>clipping</li>
<li>separate coordinate system for the motion of the clipping rectangle
and the contents</li>
!
</ul>
!
</ul>
Possible solutions:<br>
!
<ul>
<li>Separate clipping from coordinate systems. Currently, a coordinate
system defines a clip rectangle. How about specifying the coordinate system
--- 11,42 ----
<p>Open issues:<br>
</p>
!
<ul>
<li>Is the integer identifier of the coordinate system into which to
place a new coordinate system appropriate?</li>
<li>Should plain coordinate systems be usable as those ints?
<small>(Benja:) "Plain coordinate systems"?</small></li>
!
<ul>
<li>What are the semantics there? Current, just translate, is not good.
However, using the vob-internal CS is not really nice either, as Vob CSs
usually are in pixels, and this would be in 10s or 100s of pixels per
unit.</li>
!
</ul>
<li>The most general use case is the PP-like viewport. How is that
implemented?
You need</li>
!
<ul>
<li>clipping</li>
<li>separate coordinate system for the motion of the clipping rectangle
and the contents</li>
!
</ul>
!
</ul>
Possible solutions:<br>
!
<ul>
<li>Separate clipping from coordinate systems. Currently, a coordinate
system defines a clip rectangle. How about specifying the coordinate system
***************
*** 115,121 ****
e.g. putting an image behind a viewport transformed like that it so that
you *don't* want to transform that image. Finding the inverse transformation
there is not trivial and requires inverting a 4x4 matrix. It <b>can</b> be
done but it's nasty. I can well imagine wanting to do this. Even with
just rotations there's too much to worry about.<br>
!
</p>
<p>
--- 115,137 ----
e.g. putting an image behind a viewport transformed like that it so that
you *don't* want to transform that image. Finding the inverse transformation
there is not trivial and requires inverting a 4x4 matrix. It <b>can</b> be
done but it's nasty. I can well imagine wanting to do this. Even with
just rotations there's too much to worry about.<br>
! </p>
! <p>
! (Benja:) Ok. And you could still do the more usual case where you
<em>want</em>
! to think of the inner coordinate system relative to the outer: you
can
! still put your transformation coordsys inside your clipping
coordsys...
! </p>
! <p>
! (Benja:) Hmmm, issue: Before hierarchical coordsys, we used coordsys
essentially
! as bounding boxes for vobs (ok, different in pp, through the (AFAIK)
! complicated PP viewport mechanism). But a coordsys is actually a
cross
! between a box and a coordinate transformation to you, if I understand
! correctly: you want to use the vectors inside the coordsys as the
unit
! vectors for transformation coordsys in your hierarchical scheme
! (meaning that when using OrthoCoorder, you would often create
coordsys
! with width = height = 1, because you do not want scaling).
! This isn't very elegant, especially because vobs aren't truly
! (graphically) scaled by changing their coordsys' width and height...
Hm
</p>
<p>
***************
*** 149,152 ****
<br>
<br>
<br>
! </body></html>
\ No newline at end of file
--- 165,168 ----
<br>
<br>
<br>
! </body></html>
- [Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html, Tuomas J. Lukka, 2002/08/27
- [Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html, Tuomas J. Lukka, 2002/08/27
- [Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html, Tuomas J. Lukka, 2002/08/27
- [Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html, Tuomas J. Lukka, 2002/08/30
- [Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html, Benja Fallenstein, 2002/08/30
- [Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html, Tuomas J. Lukka, 2002/08/30
- [Gzz-commits] gzz/doc/pegboard/1003 PEG_1003.html,
Benja Fallenstein <=