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

[Tuomas J. Lukka]

CVSROOT:        /cvsroot/gzz
Module name:    gzz
Changes by:     Tuomas J. Lukka <address@hidden>        02/11/12 07:31:25

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

Log message:
        Funny reorg

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/Manuscripts/Irregu/irregu.tex.diff?tr1=1.23&tr2=1.24&r1=text&r2=text

Patches:
Index: gzz/Documentation/Manuscripts/Irregu/irregu.tex
diff -u gzz/Documentation/Manuscripts/Irregu/irregu.tex:1.23 
gzz/Documentation/Manuscripts/Irregu/irregu.tex:1.24
--- gzz/Documentation/Manuscripts/Irregu/irregu.tex:1.23        Tue Nov 12 
07:22:22 2002
+++ gzz/Documentation/Manuscripts/Irregu/irregu.tex     Tue Nov 12 07:31:25 2002
@@ -143,10 +143,11 @@
 detail ... focusing user attention. Conveying semantic information:
 unfinishedness... (cite architectural study) 
 
----
+However, the work on non-photorealistic rendering has been concentrated
+more on rendering polygonal 3D models in ways which resemble 
 
-In this article, we use non-photorealistic tearing as a visual cue
-in showing viewports.
+
+---
 
 
%http://portal.acm.org/citation.cfm?id=344779.345075&coll=portal&dl=ACM&type=series&idx=SERIES382&part=series&WantType=Proceedings&title=SIGGRAPH&CFID=5569444&CFTOKEN=2720008
 %      Non-photorealistic virtual environments
@@ -176,11 +177,18 @@
 
 Contribution of this article
 
-\section{Tearing}
+In this article, we use non-photorealistic tearing as a visual cue
+in showing viewports. First, we describe the reasons and design issues and
+which features are desirable. Next, we describe a mathematical solution to the
+geometric problem and discuss a hardware-accelerated implementation.
+Finally, we discuss some example applications.
 
+\section{Tearing}
 
 - basic model: rectangular paper, of which a convex region is shown
 
+\subsection{Why}
+
 A smooth rectangular or elliptical frame can make small viewports seem 
claustrophobic. 
 One reason for this is that the frame is often visually too small for its 
contents
 to yield a balanced graphical design. For example, 
@@ -191,16 +199,20 @@
 The torn edge separates itself visually from the content, alleviating
 the ...
 
+% - moving the tear-away area cannot be done with real paper\\
 
 Considered from a purely physical viewpoint, the tearout is not really
 a good metaphor\cite{kuhn91formalization}:
-a real torn piece of paper cannot move, with the edges rippling etc.
-However, similar tearing has been used in technical drawings for quite some
-time to indicate that the depicted object extends beyond the part drawn in the 
diagram.
+a real torn piece of paper cannot change the place from where it is torn, with 
the edges rippling etc.
+However, similar jagged edges have been used in technical drawings for quite 
some
+time to indicate that the depicted object extends beyond the part drawn in the 
diagram;
+this is the metaphor we wish to hang our construction on.
 
 Because of this, it should be readily comprehensible
 to users that we're not tearing the original paper but only a depiction of it.
 
+\subsection{What}
+
 - distinguishing between edges of paper and the viewport useful
 - edge of paper = line, edge of viewport = torn
 - motion: mustn't look like a "window" sliding on top of paper, but
@@ -209,7 +221,6 @@
 - natural visualisation of a piece of a large paper\\
 - in a computer user interface a piece of paper can be torn without destroying 
the original\\
 
-- moving the tear-away area cannot be done with real paper\\
 - the movement should be visualized in a comprehensible way\\
 - the torn shape of a point on an edge should be a continuous function of the 
point's location on the paper\\
 - the function should change slowly enough so that the dot product of movement 
direction and edge normal
@@ -230,7 +241,7 @@
 
 Edge shapes: attached and sprinkled.
 
-\section{Mathematical solution} 
+\subsection{How} 
 
 Surface defined by $(x, y, f(x,y))$.
 The jagged version of an edge in the $z=0$ plane is obtained by first