--- ray/doc/man/man1/rcontrib.1 2012/06/14 22:51:04 1.5 +++ ray/doc/man/man1/rcontrib.1 2014/07/11 01:52:38 1.8 @@ -1,4 +1,4 @@ -.\" RCSid "$Id: rcontrib.1,v 1.5 2012/06/14 22:51:04 greg Exp $" +.\" RCSid "$Id: rcontrib.1,v 1.8 2014/07/11 01:52:38 greg Exp $" .TH RCONTRIB 1 5/25/05 RADIANCE .SH NAME rcontrib - compute contribution coefficients in a RADIANCE scene @@ -101,9 +101,9 @@ The option tells .I rcontrib how many rays to accumulate for each record. -The default value is 1, meaning a full record will be produced for +The default value is one, meaning a full record will be produced for each input ray. -For values greater than 1, contributions will be averaged together +For values greater than one, contributions will be averaged together over the given number of input rays. If set to zero, only a single record will be produced at the very end, corresponding to the sum of all rays given on the input @@ -113,8 +113,9 @@ This is equivalent to passing all the output records t to sum RGB values together, but is much more efficient. Using this option, it is possible to reverse sampling, sending rays from a parallel source such as the sun to a diffuse surface, for example. -Note that output flushing via zero-direction rays is disabled -for accumulated evaluations. +Note that output flushing via zero-direction rays is disabled with +.I \-c +set to zero. .PP The output of .I rcontrib @@ -168,9 +169,8 @@ it has been defined via a previous or .I \-e option. -Since bin numbers start from 0, the bin count is always equal to -the last bin plus 1. -Set the this value to 0 if the bin count is unknown (the default). +Since bin numbers start from zero, the bin count is always equal to +the last bin plus one. The most recent .I \-b, .I \-bn @@ -185,7 +185,7 @@ and .I \-y if the .I \-c -is 0, when they control the resolution string +is zero, when they control the resolution string produced in the corresponding output. .PP If a @@ -203,6 +203,9 @@ arguments and files read using the option. The computed bin value will be rounded to the nearest whole number. +For a single bin, you may specify +.I "\-b 0", +which is the default. This mechanism allows the user to define precise regions or directions they wish to accumulate, such as the Tregenza sky discretization, which would be otherwise impossible to specify @@ -211,7 +214,7 @@ The rules and predefined functions available for these described in the .I rcalc(1) man page. -Unlike +Like .I rcalc, .I rcontrib will search the RADIANCE library directories for each file given in a @@ -286,8 +289,8 @@ pcomb \-c 100 90 75 c_light1.hdr \-c 50 55 57 c_light2 .PP To compute an array of illuminance contributions according to a Tregenza sky: .IP "" .2i -rcontrib \-I+ \-b tbin \-o sky.dat \-m skyglow \-b 0 \-o ground.dat \-m groundglow -@render.opt \-f tregenza.cal scene.oct < test.dat +rcontrib \-I+ \-f tregenza.cal \-b tbin \-bn Ntbins \-o sky.dat \-m skyglow +\-b 0 \-o ground.dat \-m groundglow @render.opt scene.oct < test.dat .SH ENVIRONMENT RAYPATH path to search for \-f and \-M files .SH AUTHOR