--- ray/doc/man/man1/rpict.1 2005/05/31 18:01:08 1.8 +++ ray/doc/man/man1/rpict.1 2008/11/10 19:08:17 1.13 @@ -1,4 +1,4 @@ -.\" RCSid "$Id: rpict.1,v 1.8 2005/05/31 18:01:08 greg Exp $" +.\" RCSid "$Id: rpict.1,v 1.13 2008/11/10 19:08:17 greg Exp $" .TH RPICT 1 2/26/99 RADIANCE .SH NAME rpict - generate a RADIANCE picture @@ -70,13 +70,21 @@ A cylindrical panorma may be selected by setting to the letter 'c'. This view is like a standard perspective vertically, but projected on a cylinder horizontally (like a soupcan's-eye view). -Two fisheye views are provided as well; 'h' yields a hemispherical fisheye -view and 'a' results in angular fisheye distortion. +Three fisheye views are provided as well; 'h' yields a hemispherical fisheye +view, 'a' results in angular fisheye distortion, and 's' +results in a planisphere (stereographic) projection. A hemispherical fisheye is a projection of the hemisphere onto a circle. The maximum view angle for this type is 180 degrees. An angular fisheye view is defined such that distance from the center of the image is proportional to the angle from the central view direction. An angular fisheye can display a full 360 degrees. +A planisphere fisheye view maintains angular relationships between lines, +and is commonly used for sun path analysis. +This is more commonly known as a +"stereographic projection," but we avoid the term here so as not to +confuse it with a stereoscopic pair. +A planisphere fisheye can display up to (but not including) 360 degrees, +although distortion becomes extreme as this limit is approached. Note that there is no space between the view type option and its single letter argument. .TP @@ -152,7 +160,7 @@ This is option is useful for generating skewed perspec rendering an image a piece at a time. A value of 1 means that the rendered image starts just to the right of the normal view. -A value of -1 would be to the left. +A value of \-1 would be to the left. Larger or fractional values are permitted as well. .TP .BI -vl \ val @@ -263,7 +271,7 @@ A warning about aiming failure will issued if .I frac is too large. It is usually wise to turn off image sampling when using -direct jitter by setting -ps to 1. +direct jitter by setting \-ps to 1. .TP .BI -ds \ frac Set the direct sampling ratio to @@ -555,6 +563,12 @@ though the .I \-dv option (above) may be used to override this. .TP +.BR \-u +Boolean switch to control uncorrelated random sampling. +When "off", a low-discrepancy sequence is used, which reduces +variance but can result in a brushed appearance in specular highlights. +When "on", pure Monte Carlo sampling is used in all calculations. +.TP .BI -lr \ N Limit reflections to a maximum of .I N. @@ -768,7 +782,7 @@ Set the time between progress reports to A progress report writes the number of rays traced, the percentage completed, and the CPU usage to the standard error. Reports are given either automatically after the specified interval, -or when the process receives a continue (-CONT) signal (see +or when the process receives a continue (\-CONT) signal (see .I kill(1)). A value of zero turns automatic reporting off. .TP @@ -782,9 +796,9 @@ Boolean switch for warning messages. The default is to print warnings, so the first appearance of this option turns them off. .SH EXAMPLE -rpict -vp 10 5 3 -vd 1 -.5 0 scene.oct > scene.pic +rpict \-vp 10 5 3 \-vd 1 \-.5 0 scene.oct > scene.hdr .PP -rpict -S 1 -o frame%02d.pic scene.oct < keyframes.vf +rpict \-S 1 \-o frame%02d.hdr scene.oct < keyframes.vf .SH ENVIRONMENT RAYPATH the directories to check for auxiliary files. .SH FILES