[Gzz-commits] gzz/Documentation/Manuscripts Irregu/irregu.tex...

[Tuomas J. Lukka]

CVSROOT:        /cvsroot/gzz
Module name:    gzz
Changes by:     Tuomas J. Lukka <address@hidden>        02/11/30 03:34:58

Modified files:
        Documentation/Manuscripts/Irregu: irregu.tex 
        Documentation/Manuscripts/Paper: paper.tex 

Log message:
        twid

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/Manuscripts/Irregu/irregu.tex.diff?tr1=1.100&tr2=1.101&r1=text&r2=text
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/Manuscripts/Paper/paper.tex.diff?tr1=1.102&tr2=1.103&r1=text&r2=text

Patches:
Index: gzz/Documentation/Manuscripts/Irregu/irregu.tex
diff -u gzz/Documentation/Manuscripts/Irregu/irregu.tex:1.100 
gzz/Documentation/Manuscripts/Irregu/irregu.tex:1.101
--- gzz/Documentation/Manuscripts/Irregu/irregu.tex:1.100       Sat Nov 30 
03:17:09 2002
+++ gzz/Documentation/Manuscripts/Irregu/irregu.tex     Sat Nov 30 03:34:57 2002
@@ -362,10 +362,9 @@
 In order to create and maintain the illusion: ``we see a piece of the 
canvas'', 
 instead of ``we see the canvas through an irregularly shaped hole'', 
 the motion must be carefully designed.
-When the viewport moves on the canvas, it 
-mustn't look like a (rectangular or irregular) 
-"window" sliding on top of paper, but
-instead something like re-gluing and tearing away a different part of the 
paper.
+The shape of the torn piece should not be translation-invariant
+but should 
+change in an appropriate way with location and zooming.
 
 To get the correct picture, imagine an animation where the first frame is a 
given
 torn piece of paper, the next frame is what would have happened if we had torn 
the paper
@@ -378,9 +377,8 @@
 there are two main reasons to go for nonphotorealistic rendering:
 firstly, to imply to the user that the viewport does not behave
 exactly like a real paper; to make the overall view clearer.
-
-Thus, instead of trying to draw a realistic torn piece of paper, 
-we will only the silhouette edge\cite{saito90comprehensible}.
+Drawing only the silhouette edge\cite{saito90comprehensible} of the
+paper is therefore appropriate.
 
 % When zooming, scaling the thickness of the silhouette edge
 % with the scale of the paper is not good:
@@ -390,16 +388,19 @@
 % (too photorealistic...), but neither is a constant width, which ...
 % Square root XXX refs: stroke scaling in pen drawings?
 
-
-Edge shapes: connected and scattered (and intermediates).
-TOPOLOGY!
-
-Finally, there is the question of what should happen when the viewport reaches 
the edge
-of the canvas.
-- distinguishing between edges of paper and the viewport useful
-    - edge of paper = line, edge of viewport = torn
+If the usual shape of the viewport extends outside the edge of the underlying
+canvas, the metaphor of tearing demands that we only draw the 
+intersection of the two; see Fig~xxx.
 
 
+Finally, there are several design questions that are less important
+and which are best left as options in the algorithms, to be tailored
+to the particular application and taste.
+For example, whether the edge should only ripple without altering
+the topology or whether we should allow unconnected islands to
+appear (scattered edge); whether adding something to the roughly
+defined region to be viewed should always only move edges outwards 
+or whether they may move back inwards at some point (``ebbing'').
 
 
 \subsection{Algorithm ``How?''} 
Index: gzz/Documentation/Manuscripts/Paper/paper.tex
diff -u gzz/Documentation/Manuscripts/Paper/paper.tex:1.102 
gzz/Documentation/Manuscripts/Paper/paper.tex:1.103
--- gzz/Documentation/Manuscripts/Paper/paper.tex:1.102 Fri Nov 29 15:37:27 2002
+++ gzz/Documentation/Manuscripts/Paper/paper.tex       Sat Nov 30 03:34:57 2002
@@ -942,6 +942,8 @@
 to use repeating units for non-repeating backgrounds --- but use more than one,
 which are not rationally related.
 
+OTHER IDENTITY: EDGE SHAPE
+
 % \section{MPEG Animation}
 % [not to be included in final ms.]
 %