[Gzz-commits] gzz/Documentation/Manuscripts/Paper paper.tex

[Janne V. Kujala]

CVSROOT:        /cvsroot/gzz
Module name:    gzz
Changes by:     Janne V. Kujala <address@hidden>        02/11/26 09:35:24

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

Log message:
        colors and some notes

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/Manuscripts/Paper/paper.tex.diff?tr1=1.74&tr2=1.75&r1=text&r2=text

Patches:
Index: gzz/Documentation/Manuscripts/Paper/paper.tex
diff -u gzz/Documentation/Manuscripts/Paper/paper.tex:1.74 
gzz/Documentation/Manuscripts/Paper/paper.tex:1.75
--- gzz/Documentation/Manuscripts/Paper/paper.tex:1.74  Tue Nov 26 03:30:03 2002
+++ gzz/Documentation/Manuscripts/Paper/paper.tex       Tue Nov 26 09:35:23 2002
@@ -381,6 +381,7 @@
 of unique backgrounds .
 Our main platforms are NV10, i.e. OpenGL 1.3 + GL\_NV\_register\_combiners,
 and NV20, i.e. NV10 + GL\_NV\_texture\_shader2.
+% Currently we NV20 code is broken; NV25 is required for HILO_OFFSET
 
 One important goal for the implementation is that it should be easily 
 applicable in a variety of situations. 
@@ -443,7 +444,7 @@
 To address readability, we only use colors with the CIE $L^*$
 lightness value over 80 (percent of maximum).
 % Mention screen gamma earlier, maybe here.
-For correct computation of the color lightness, 
+For correct computation of the lightness, 
 it is essential that the display gamma is properly adjusted
 for linear RGB reproduction.
 % Onko lineaarinen *varmasti* oikea LAB-muunnokselle?
@@ -462,26 +463,26 @@
 %% Doesn't really need to be said here; it's what people
 %% will naturally assume.
 
-To produce compatible colors, we choose the hues from a distribution
+To produce compatible colors, we choose the hue angles from a distribution
 % To have: huonoa englantia
 concentrated on one random hue with a random variance and
-saturations chosen from an ad hoc distribution.
+saturations from an ad hoc distribution.
 This produces related colors with high probability, but still
 allows motley palettes to occur occasionally.
-
-Because the $a^*b^*$ plane of the CIE $L^*a^*b^*$ color space seems to 
-have too much blue and too little yellow for light colors, 
-we actually choose the hues by 
-interpolating uniformly between seven primary colors,
-with orange added between the hues of the usual six saturated corners
-of the RGB cube.
-% reasoning?
-
 Opposite color schemes could also be used for more variation, 
 but because the combiners can produce any color in the convex hull 
 of the palette, the interpolated colors would easily span too
 much area on the color circle.
 
+There is one problem in using the hue angles of the CIE $L^*a^*b^*$ color 
space ---
+it produces too much blue and too little yellow in the range of light colors.
+Therefore, we actually map the angles to hues using a color circle with
+evenly spaced ``primary'' hues.
+To balance the blue bias, we use seven primaries
+with orange added between the usual hues of the six saturated corners of the 
RGB cube.
+% reasoning?
+
+
 \if0
 - color contrast needed for recognizable shapes \\
 \\
@@ -509,8 +510,6 @@
 - non-componentwise color interpolation in combiners \\
 
 
-{\bf jvk}
-
 READABILITY - screen gamma
 \fi
 
@@ -661,8 +660,6 @@
 single perceived layer.
 
 We use 3 passes on NV10 and 2 passes on NV20. 
-
-{\bf jvk}
 
 \subsection{Texture shading}