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.\" RCSid "$Id" |
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.TH RPICT 1 2/26/99 RADIANCE |
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.SH NAME |
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rpict - generate a RADIANCE picture |
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.SH SYNOPSIS |
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.B rpict |
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[ |
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.B options |
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] |
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[ |
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.B $EVAR |
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] |
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[ |
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.B @file |
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] |
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[ |
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.B octree |
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] |
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.br |
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.B "rpict [ options ] \-defaults" |
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.SH DESCRIPTION |
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.I Rpict |
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generates a picture from the RADIANCE scene given in |
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.I octree |
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and sends it to the standard output. |
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If no |
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.I octree |
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is given, the standard input is read. |
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(The octree may also be specified as the output of a command |
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enclosed in quotes and preceded by a `!'.)\0 |
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Options specify the viewing parameters as well as |
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giving some control over the calculation. |
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Options may be given on the command line and/or read from the |
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environment and/or read from a file. |
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A command argument beginning with a dollar sign ('$') is immediately |
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replaced by the contents of the given environment variable. |
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A command argument beginning with an at sign ('@') is immediately |
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replaced by the contents of the given file. |
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.PP |
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In the second form shown above, the default values |
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for the options (modified by those options present) |
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are printed with a brief explanation. |
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.PP |
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Most options are followed by one or more arguments, which must be |
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separated from the option and each other by white space. |
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The exceptions to this rule are the |
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.I \-vt |
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option and the boolean options. |
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Normally, the appearance of a boolean option causes a feature to |
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be "toggled", that is switched from off to on or on to off |
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depending on its previous state. |
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Boolean options may also be set |
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explicitly by following them immediately with a '+' or '-', meaning |
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on or off, respectively. |
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Synonyms for '+' are any of the characters "yYtT1", and synonyms |
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for '-' are any of the characters "nNfF0". |
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All other characters will generate an error. |
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.TP 10n |
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.BI -vt t |
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Set view type to |
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.I t. |
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If |
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.I t |
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is 'v', a perspective view is selected. |
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If |
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.I t |
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is 'l', a parallel view is used. |
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A cylindrical panorma may be selected by setting |
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.I t |
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to the letter 'c'. |
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This view is like a standard perspective vertically, but projected |
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on a cylinder horizontally (like a soupcan's-eye view). |
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Two fisheye views are provided as well; 'h' yields a hemispherical fisheye |
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view and 'a' results in angular fisheye distortion. |
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A hemispherical fisheye is a projection of the hemisphere onto a circle. |
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The maximum view angle for this type is 180 degrees. |
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An angular fisheye view is defined such that distance from the center of |
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the image is proportional to the angle from the central view direction. |
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An angular fisheye can display a full 360 degrees. |
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Note that there is no space between the view type |
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option and its single letter argument. |
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.TP |
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.BI -vp " x y z" |
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Set the view point to |
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.I "x y z". |
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This is the focal point of a perspective view or the |
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center of a parallel projection. |
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.TP |
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.BI -vd " xd yd zd" |
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Set the view direction vector to |
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.I "xd yd zd". |
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.TP |
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.BI -vu " xd yd zd" |
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Set the view up vector (vertical direction) to |
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.I "xd yd zd". |
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.TP |
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.BI -vh \ val |
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Set the view horizontal size to |
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.I val. |
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For a perspective projection (including fisheye views), |
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.I val |
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is the horizontal field of view (in degrees). |
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For a parallel projection, |
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.I val |
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is the view width in world coordinates. |
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.TP |
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.BI -vv \ val |
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Set the view vertical size to |
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.I val. |
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.TP |
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.BI -vo \ val |
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Set the view fore clipping plane at a distance of |
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.I val |
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from the view point. |
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The plane will be perpendicular to the view direction for |
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perspective and parallel view types. |
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For fisheye view types, the clipping plane is actually a clipping |
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sphere, centered on the view point with radius |
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.I val. |
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Objects in front of this imaginary surface will not be visible. |
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This may be useful for seeing through walls (to get a longer |
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perspective from an exterior view point) or for incremental |
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rendering. |
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A value of zero implies no foreground clipping. |
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A negative value produces some interesting effects, since it creates an |
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inverted image for objects behind the viewpoint. |
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This possibility is provided mostly for the purpose of rendering |
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stereographic holograms. |
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.TP |
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.BI -va \ val |
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Set the view aft clipping plane at a distance of |
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.I val |
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from the view point. |
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Like the view fore plane, it will be perpendicular to the view |
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direction for perspective and parallel view types. |
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For fisheye view types, the clipping plane is actually a clipping |
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sphere, centered on the view point with radius |
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.I val. |
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Objects behind this imaginary surface will not be visible. |
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A value of zero means no aft clipping, and is the only way to see |
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infinitely distant objects such as the sky. |
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.TP |
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.BI -vs \ val |
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Set the view shift to |
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.I val. |
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This is the amount the actual image will be shifted to the right of |
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the specified view. |
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This is option is useful for generating skewed perspectives or |
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rendering an image a piece at a time. |
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A value of 1 means that the rendered image starts just to the right of |
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the normal view. |
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A value of -1 would be to the left. |
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Larger or fractional values are permitted as well. |
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.TP |
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.BI -vl \ val |
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Set the view lift to |
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.I val. |
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This is the amount the actual image will be lifted up from the |
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specified view, similar to the |
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.I \-vs |
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option. |
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.TP |
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.BI -vf \ file |
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Get view parameters from |
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.I file, |
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which may be a picture or a file created by rview (with the "view" command). |
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.TP |
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.BI -x \ res |
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Set the maximum x resolution to |
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.I res. |
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.TP |
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.BI -y \ res |
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Set the maximum y resolution to |
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.I res. |
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.TP |
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.BI -pa \ rat |
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Set the pixel aspect ratio (height over width) to |
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.I rat. |
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Either the x or the y resolution will be reduced so that the pixels have |
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this ratio for the specified view. |
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If |
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.I rat |
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is zero, then the x and y resolutions will adhere to the given maxima. |
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.TP |
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.BI -ps \ size |
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Set the pixel sample spacing to the integer |
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.I size. |
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This specifies the sample spacing (in pixels) for adaptive subdivision |
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on the image plane. |
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.TP |
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.BI -pt \ frac |
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Set the pixel sample tolerance to |
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.I frac. |
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If two samples differ by more than this amount, a third |
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sample is taken between them. |
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.TP |
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.BI -pj \ frac |
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Set the pixel sample jitter to |
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.I frac. |
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Distributed ray-tracing performs anti-aliasing by randomly sampling |
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over pixels. |
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A value of one will randomly distribute samples over full |
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pixels. |
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A value of zero samples pixel centers only. |
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A value between zero and one is usually best |
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for low-resolution images. |
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.TP |
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.BI -pm \ frac |
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Set the pixel motion blur to |
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.I frac. |
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In an animated sequence, the exact view will be blurred between the previous |
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view and the next view as though a shutter were open this fraction of a |
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frame time. |
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(See the |
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.I \-S |
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option regarding animated sequences.)\0 |
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The first view will be blurred according to the difference between the |
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initial view set on the command line and the first view taken from the |
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standard input. |
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It is not advisable to use this option in combination with the |
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.I pmblur(1) |
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program, since one takes the place of the other. |
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However, it may improve results with |
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.I pmblur |
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to use a very small fraction with the |
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.I \-pm |
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option, to avoid the ghosting effect of too few time samples. |
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.TP |
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.BI -dj \ frac |
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Set the direct jittering to |
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.I frac. |
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A value of zero samples each source at specific sample points |
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(see the |
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.I \-ds |
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option below), giving a smoother but somewhat less accurate |
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rendering. |
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A positive value causes rays to be distributed over each |
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source sample according to its size, resulting in more accurate |
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penumbras. |
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This option should never be greater than 1, and may even |
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cause problems (such as speckle) when the value is smaller. |
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A warning about aiming failure will issued if |
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.I frac |
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is too large. |
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It is usually wise to turn off image sampling when using |
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direct jitter by setting -ps to 1. |
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.TP |
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.BI -ds \ frac |
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Set the direct sampling ratio to |
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.I frac. |
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A light source will be subdivided until |
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the width of each sample area divided by the distance |
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to the illuminated point is below this ratio. |
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This assures accuracy in regions close to large area sources |
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at a slight computational expense. |
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A value of zero turns source subdivision off, sending at most one |
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shadow ray to each light source. |
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.TP |
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.BI -dt \ frac |
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Set the direct threshold to |
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.I frac. |
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Shadow testing will stop when the potential contribution of at least |
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the next and at most all remaining light source samples is less than |
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this fraction of the accumulated value. |
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(See the |
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.I \-dc |
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option below.)\0 |
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The remaining light source contributions are approximated |
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statistically. |
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A value of zero means that all light source samples will be tested for shadow. |
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.TP |
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.BI \-dc \ frac |
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Set the direct certainty to |
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.I frac. |
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A value of one guarantees that the absolute accuracy of the direct calculation |
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will be equal to or better than that given in the |
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.I \-dt |
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specification. |
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A value of zero only insures that all shadow lines resulting in a contrast |
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change greater than the |
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.I \-dt |
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specification will be calculated. |
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.TP |
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.BI -dr \ N |
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Set the number of relays for secondary sources to |
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.I N. |
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A value of 0 means that secondary sources will be ignored. |
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A value of 1 means that sources will be made into first generation |
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secondary sources; a value of 2 means that first generation |
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secondary sources will also be made into second generation secondary |
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sources, and so on. |
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.TP |
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.BI -dp \ D |
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Set the secondary source presampling density to D. |
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This is the number of samples per steradian |
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that will be used to determine ahead of time whether or not |
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it is worth following shadow rays through all the reflections and/or |
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transmissions associated with a secondary source path. |
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A value of 0 means that the full secondary source path will always |
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be tested for shadows if it is tested at all. |
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.TP |
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.BR \-dv |
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Boolean switch for light source visibility. |
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With this switch off, sources will be black when viewed directly |
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although they will still participate in the direct calculation. |
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This option may be desirable in conjunction with the |
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.I \-i |
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option so that light sources do not appear in the output. |
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.TP |
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.BI -sj \ frac |
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Set the specular sampling jitter to |
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.I frac. |
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This is the degree to which the highlights are sampled |
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for rough specular materials. |
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A value of one means that all highlights will be fully sampled |
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using distributed ray tracing. |
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A value of zero means that no jittering will take place, and all |
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reflections will appear sharp even when they should be diffuse. |
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This may be desirable when used in combination with image sampling |
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(see |
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.I \-ps |
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option above) to obtain faster renderings. |
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.TP |
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.BI -st \ frac |
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Set the specular sampling threshold to |
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.I frac. |
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This is the minimum fraction of reflection or transmission, under which |
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no specular sampling is performed. |
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A value of zero means that highlights will always be sampled by |
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tracing reflected or transmitted rays. |
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A value of one means that specular sampling is never used. |
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Highlights from light sources will always be correct, but |
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reflections from other surfaces will be approximated using an |
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ambient value. |
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A sampling threshold between zero and one offers a compromise between image |
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accuracy and rendering time. |
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.TP |
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.BR -bv |
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Boolean switch for back face visibility. |
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With this switch off, back faces of opaque objects will be invisible |
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to all rays. |
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This is dangerous unless the model was constructed such that |
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all surface normals on opaque objects face outward. |
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Although turning off back face visibility does not save much |
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computation time under most circumstances, it may be useful as a |
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tool for scene debugging, or for seeing through one-sided walls from |
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the outside. |
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This option has no effect on transparent or translucent materials. |
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.TP |
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.BI -av " red grn blu" |
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Set the ambient value to a radiance of |
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.I "red grn blu". |
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This is the final value used in place of an |
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indirect light calculation. |
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If the number of ambient bounces is one or greater and the ambient |
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value weight is non-zero (see |
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.I -aw |
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and |
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.I -ab |
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below), this value may be modified by the computed indirect values |
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to improve overall accuracy. |
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.TP |
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.BI -aw \ N |
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Set the relative weight of the ambient value given with the |
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.I -av |
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option to |
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.I N. |
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As new indirect irradiances are computed, they will modify the |
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default ambient value in a moving average, with the specified weight |
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assigned to the initial value given on the command and all other |
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weights set to 1. |
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If a value of 0 is given with this option, then the initial ambient |
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value is never modified. |
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This is the safest value for scenes with large differences in |
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indirect contributions, such as when both indoor and outdoor |
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(daylight) areas are visible. |
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.TP |
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.BI -ab \ N |
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Set the number of ambient bounces to |
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.I N. |
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This is the maximum number of diffuse bounces |
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computed by the indirect calculation. |
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A value of zero implies no indirect calculation. |
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.TP |
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.BI -ar \ res |
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Set the ambient resolution to |
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.I res. |
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This number will determine the maximum density of ambient values |
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used in interpolation. |
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Error will start to increase on surfaces spaced closer than |
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the scene size divided by the ambient resolution. |
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The maximum ambient value density is the scene size times the |
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ambient accuracy (see the |
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.I \-aa |
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option below) divided by the ambient resolution. |
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The scene size can be determined using |
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.I getinfo(1) |
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with the |
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.I \-d |
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option on the input octree. |
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|
|
A value of zero is interpreted as unlimited resolution. |
402 |
|
|
.TP |
403 |
|
|
.BI -aa \ acc |
404 |
|
|
Set the ambient accuracy to |
405 |
|
|
.I acc. |
406 |
|
|
This value will approximately equal the error |
407 |
|
|
from indirect illuminance interpolation. |
408 |
|
|
A value of zero implies no interpolation. |
409 |
|
|
.TP |
410 |
|
|
.BI -ad \ N |
411 |
|
|
Set the number of ambient divisions to |
412 |
|
|
.I N. |
413 |
|
|
The error in the Monte Carlo calculation of indirect |
414 |
|
|
illuminance will be inversely proportional to the square |
415 |
|
|
root of this number. |
416 |
|
|
A value of zero implies no indirect calculation. |
417 |
|
|
.TP |
418 |
|
|
.BI -as \ N |
419 |
|
|
Set the number of ambient super-samples to |
420 |
|
|
.I N. |
421 |
|
|
Super-samples are applied only to the ambient divisions which |
422 |
|
|
show a significant change. |
423 |
|
|
.TP |
424 |
|
|
.BI -af \ fname |
425 |
|
|
Set the ambient file to |
426 |
|
|
.I fname. |
427 |
|
|
This is where indirect illuminance will be stored and retrieved. |
428 |
|
|
Normally, indirect illuminance values are kept in memory and |
429 |
|
|
lost when the program finishes or dies. |
430 |
|
|
By using a file, different invocations can share illuminance |
431 |
|
|
values, saving time in the computation. |
432 |
|
|
Also, by creating an ambient file during a low resolution rendering, |
433 |
|
|
better results can be obtained in a second high resolution pass. |
434 |
|
|
The ambient file is in a machine-independent binary format |
435 |
|
|
which may be examined with |
436 |
|
|
.I lookamb(1). |
437 |
|
|
.IP |
438 |
|
|
The ambient file may also be used as a means of communication and |
439 |
|
|
data sharing between simultaneously executing processes. |
440 |
|
|
The same file may be used by multiple processes, possibly running on |
441 |
|
|
different machines and accessing the file via the network (ie. |
442 |
|
|
.I nfs(4)). |
443 |
|
|
The network lock manager |
444 |
|
|
.I lockd(8) |
445 |
|
|
is used to insure that this information is used consistently. |
446 |
|
|
.IP |
447 |
|
|
If any calculation parameters are changed or the scene |
448 |
|
|
is modified, the old ambient file should be removed so that |
449 |
|
|
the calculation can start over from scratch. |
450 |
|
|
For convenience, the original ambient parameters are listed in the |
451 |
|
|
header of the ambient file. |
452 |
|
|
.I Getinfo(1) |
453 |
|
|
may be used to print out this information. |
454 |
|
|
.TP |
455 |
|
|
.BI -ae \ mat |
456 |
|
|
Append |
457 |
|
|
.I mat |
458 |
|
|
to the ambient exclude list, |
459 |
|
|
so that it will not be considered during the indirect calculation. |
460 |
|
|
This is a hack for speeding the indirect computation by |
461 |
|
|
ignoring certain objects. |
462 |
|
|
Any object having |
463 |
|
|
.I mat |
464 |
|
|
as its modifier will get the default ambient |
465 |
|
|
level rather than a calculated value. |
466 |
|
|
Any number of excluded materials may be given, but each |
467 |
|
|
must appear in a separate option. |
468 |
|
|
.TP |
469 |
|
|
.BI -ai \ mat |
470 |
|
|
Add |
471 |
|
|
.I mat |
472 |
|
|
to the ambient include list, |
473 |
|
|
so that it will be considered during the indirect calculation. |
474 |
|
|
The program can use either an include list or an exclude |
475 |
|
|
list, but not both. |
476 |
|
|
.TP |
477 |
|
|
.BI -aE \ file |
478 |
|
|
Same as |
479 |
|
|
.I \-ae, |
480 |
|
|
except read materials to be excluded from |
481 |
|
|
.I file. |
482 |
|
|
The RAYPATH environment variable determines which directories are |
483 |
|
|
searched for this file. |
484 |
|
|
The material names are separated by white space in the file. |
485 |
|
|
.TP |
486 |
|
|
.BI -aI \ file |
487 |
|
|
Same as |
488 |
|
|
.I \-ai, |
489 |
|
|
except read materials to be included from |
490 |
|
|
.I file. |
491 |
|
|
.TP |
492 |
|
|
.BI -me " rext gext bext" |
493 |
|
|
Set the global medium extinction coefficient to the indicated color, |
494 |
|
|
in units of 1/distance (distance in world coordinates). |
495 |
|
|
Light will be scattered or absorbed over distance according to |
496 |
|
|
this value. |
497 |
|
|
The ratio of scattering to total scattering plus absorption is set |
498 |
|
|
by the albedo parameter, described below. |
499 |
|
|
.TP |
500 |
|
|
.BI -ma " ralb galb balb" |
501 |
|
|
Set the global medium albedo to the given value between 0\00\00 |
502 |
|
|
and 1\01\01. |
503 |
|
|
A zero value means that all light not transmitted by the medium |
504 |
|
|
is absorbed. |
505 |
|
|
A unitary value means that all light not transmitted by the medium |
506 |
|
|
is scattered in some new direction. |
507 |
|
|
The isotropy of scattering is determined by the Heyney-Greenstein |
508 |
|
|
parameter, described below. |
509 |
|
|
.TP |
510 |
|
|
.BI \-mg \ gecc |
511 |
|
|
Set the medium Heyney-Greenstein eccentricity parameter to |
512 |
|
|
.I gecc. |
513 |
|
|
This parameter determines how strongly scattering favors the forward |
514 |
|
|
direction. |
515 |
|
|
A value of 0 indicates perfectly isotropic scattering. |
516 |
|
|
As this parameter approaches 1, scattering tends to prefer the |
517 |
|
|
forward direction. |
518 |
|
|
.TP |
519 |
|
|
.BI \-ms \ sampdist |
520 |
|
|
Set the medium sampling distance to |
521 |
|
|
.I sampdist, |
522 |
|
|
in world coordinate units. |
523 |
|
|
During source scattering, this will be the average distance between |
524 |
|
|
adjacent samples. |
525 |
|
|
A value of 0 means that only one sample will be taken per light |
526 |
|
|
source within a given scattering volume. |
527 |
|
|
.TP |
528 |
|
|
.BR \-i |
529 |
|
|
Boolean switch to compute irradiance rather than radiance values. |
530 |
|
|
This only affects the final result, substituting a Lambertian |
531 |
|
|
surface and multiplying the radiance by pi. |
532 |
|
|
Glass and other transparent surfaces are ignored during this stage. |
533 |
|
|
Light sources still appear with their original radiance values, |
534 |
|
|
though the |
535 |
|
|
.I \-dv |
536 |
|
|
option (above) may be used to override this. |
537 |
|
|
.TP |
538 |
|
|
.BI -lr \ N |
539 |
|
|
Limit reflections to a maximum of |
540 |
|
|
.I N. |
541 |
|
|
.TP |
542 |
|
|
.BI -lw \ frac |
543 |
|
|
Limit the weight of each ray to a minimum of |
544 |
|
|
.I frac. |
545 |
|
|
During ray-tracing, a record is kept of the final contribution |
546 |
|
|
a ray would have to the image. |
547 |
|
|
If it is less then the specified minimum, the ray is not traced. |
548 |
|
|
.TP |
549 |
|
|
.BI -S \ seqstart |
550 |
|
|
Instead of generating a single picture based only on the view |
551 |
|
|
parameters given on the command line, this option causes |
552 |
|
|
.I rpict |
553 |
|
|
to read view options from the standard input and for each line |
554 |
|
|
containing a valid view specification, generate a corresponding |
555 |
|
|
picture. |
556 |
|
|
This option is most useful for generating animated sequences, though |
557 |
|
|
it may also be used to control rpict from a remote process for |
558 |
|
|
network-distributed rendering. |
559 |
|
|
.I Seqstart |
560 |
|
|
is a positive integer that will be associated with the first output |
561 |
|
|
frame, and incremented for successive output frames. |
562 |
|
|
By default, each frame is concatenated to the output stream, but it |
563 |
|
|
is possible to change this action using the |
564 |
|
|
.I \-o |
565 |
|
|
option (described below). |
566 |
|
|
Multiple frames may be later extracted from the output using |
567 |
|
|
.I ra_rgbe(1). |
568 |
|
|
.IP |
569 |
|
|
Note that the octree may not be read from the standard input when |
570 |
|
|
using this option. |
571 |
|
|
.TP |
572 |
|
|
.BI -o \ fspec |
573 |
|
|
Send the picture(s) to the file(s) given by |
574 |
|
|
.I fspec |
575 |
|
|
instead of the standard output. |
576 |
|
|
If this option is used in combination with |
577 |
|
|
.I \-S |
578 |
|
|
and |
579 |
|
|
.I fspec |
580 |
|
|
contains an integer field for |
581 |
|
|
.I printf(3) |
582 |
|
|
(eg. "%03d") then the actual output file name will include |
583 |
|
|
the current frame number. |
584 |
|
|
.I Rpict |
585 |
|
|
will not allow a picture file to be clobbered (overwritten) |
586 |
|
|
with this option. |
587 |
|
|
If an image in a sequence already exists |
588 |
|
|
.I (\-S |
589 |
|
|
option), |
590 |
|
|
.I rpict |
591 |
|
|
will skip until it reaches an image that doesn't, or the end of |
592 |
|
|
the sequence. |
593 |
|
|
This is useful for running rpict on multiple machines or processors |
594 |
|
|
to render the same sequence, as each process will skip to the next |
595 |
|
|
frame that needs rendering. |
596 |
|
|
.TP |
597 |
|
|
.BI -r \ fn |
598 |
|
|
Recover pixel information from the file |
599 |
|
|
.I fn. |
600 |
|
|
If the program gets killed during picture generation, the information |
601 |
|
|
may be recovered using this option. |
602 |
|
|
The view parameters and picture dimensions are also recovered from |
603 |
|
|
.I fn |
604 |
|
|
if possible. |
605 |
|
|
The other options should be identical to those which created |
606 |
|
|
.I fn, |
607 |
|
|
or an inconsistent picture may result. |
608 |
|
|
If |
609 |
|
|
.I fn |
610 |
|
|
is identical to the file specification given with the |
611 |
|
|
.I \-o |
612 |
|
|
option, |
613 |
|
|
.I rpict |
614 |
|
|
will rename the file prior to copying its contents. |
615 |
|
|
This insures that the old file is not overwritten accidentally. |
616 |
|
|
(See also the |
617 |
|
|
.I \-ro |
618 |
|
|
option, below.)\0 |
619 |
|
|
.IP |
620 |
|
|
If |
621 |
|
|
.I fn |
622 |
|
|
is an integer and the recover option is used in combination with the |
623 |
|
|
.I \-S |
624 |
|
|
option, then |
625 |
|
|
.I rpict |
626 |
|
|
skips a number of view specifications on its input equal to the |
627 |
|
|
difference between |
628 |
|
|
.I fn |
629 |
|
|
and |
630 |
|
|
.I seqstart. |
631 |
|
|
.I Rpict |
632 |
|
|
then performs a recovery operation on the file constructed from the |
633 |
|
|
frame number |
634 |
|
|
.I fn |
635 |
|
|
and the output file specification given with the |
636 |
|
|
.I \-o |
637 |
|
|
option. |
638 |
|
|
This provides a convenient mechanism for recovering in the middle of |
639 |
|
|
an aborted picture sequence. |
640 |
|
|
.IP |
641 |
|
|
The recovered file |
642 |
|
|
will be removed if the operation is successful. |
643 |
|
|
If the recover operation fails (due to lack of disk space) |
644 |
|
|
and the output file and recover file specifications |
645 |
|
|
are the same, then the original information may be left in a |
646 |
|
|
renamed temporary file. |
647 |
|
|
(See FILES section, below.)\0 |
648 |
|
|
.TP |
649 |
|
|
.BI -ro \ fspec |
650 |
|
|
This option causes pixel information to be recovered from and |
651 |
|
|
subsequently returned to the picture file |
652 |
|
|
.I fspec. |
653 |
|
|
The effect is the same as specifying identical recover and output |
654 |
|
|
file names with the |
655 |
|
|
.I \-r |
656 |
|
|
and |
657 |
|
|
.I \-o |
658 |
|
|
options. |
659 |
|
|
.TP |
660 |
|
|
.BI -z \ fspec |
661 |
|
|
Write pixel distances out to the file |
662 |
|
|
.I fspec. |
663 |
|
|
The values are written as short floats, one per pixel in scanline order, |
664 |
|
|
as required by |
665 |
|
|
.I pinterp(1). |
666 |
|
|
Similar to the |
667 |
|
|
.I \-o |
668 |
|
|
option, the actual file name will be constructed using |
669 |
|
|
.I printf |
670 |
|
|
and the frame number from the |
671 |
|
|
.I \-S |
672 |
|
|
option. |
673 |
|
|
If used with the |
674 |
|
|
.I \-r |
675 |
|
|
option, |
676 |
|
|
.I \-z |
677 |
|
|
also recovers information from an aborted rendering. |
678 |
|
|
.TP |
679 |
|
|
.BI \-P \ pfile |
680 |
|
|
Execute in a persistent mode, using |
681 |
|
|
.I pfile |
682 |
|
|
as the control file. |
683 |
|
|
This option must be used together with |
684 |
|
|
.I \-S, |
685 |
|
|
and is incompatible with the recover option |
686 |
|
|
.I (\-r). |
687 |
|
|
Persistent execution means that after reaching end-of-file on |
688 |
|
|
its input, |
689 |
|
|
.I rpict |
690 |
|
|
will fork a child process that will wait for another |
691 |
|
|
.I rpict |
692 |
|
|
command with the same |
693 |
|
|
.I \-P |
694 |
|
|
option to attach to it. |
695 |
|
|
(Note that since the rest of the command line options will be those |
696 |
|
|
of the original invocation, it is not necessary to give any arguments |
697 |
|
|
besides |
698 |
|
|
.I \-P |
699 |
|
|
for subsequent calls.) |
700 |
|
|
Killing the process is achieved with the |
701 |
|
|
.I kill(1) |
702 |
|
|
command. |
703 |
|
|
(The process ID in the first line of |
704 |
|
|
.I pfile |
705 |
|
|
may be used to identify the waiting |
706 |
|
|
.I rpict |
707 |
|
|
process.) |
708 |
|
|
This option may be less useful than the |
709 |
|
|
.I \-PP |
710 |
|
|
variation, explained below. |
711 |
|
|
.TP |
712 |
|
|
.BI \-PP \ pfile |
713 |
|
|
Execute in continuous-forking persistent mode, using |
714 |
|
|
.I pfile |
715 |
|
|
as the control file. |
716 |
|
|
The difference between this option and the |
717 |
|
|
.I \-P |
718 |
|
|
option described above is the creation of multiple duplicate |
719 |
|
|
processes to handle any number of attaches. |
720 |
|
|
This provides a simple and reliable mechanism of memory sharing |
721 |
|
|
on most multiprocessing platforms, since the |
722 |
|
|
.I fork(2) |
723 |
|
|
system call will share memory on a copy-on-write basis. |
724 |
|
|
This option may be used with |
725 |
|
|
.I rpiece(1) |
726 |
|
|
to efficiently render a single image using multiple processors |
727 |
|
|
on the same host. |
728 |
|
|
.TP |
729 |
|
|
.BI -t \ sec |
730 |
|
|
Set the time between progress reports to |
731 |
|
|
.I sec. |
732 |
|
|
A progress report writes the number of rays traced, the percentage |
733 |
|
|
completed, and the CPU usage to the standard error. |
734 |
|
|
Reports are given either automatically after the specified interval, |
735 |
|
|
or when the process receives a continue (-CONT) signal (see |
736 |
|
|
.I kill(1)). |
737 |
|
|
A value of zero turns automatic reporting off. |
738 |
|
|
.TP |
739 |
|
|
.BI -e \ efile |
740 |
|
|
Send error messages and progress reports to |
741 |
|
|
.I efile |
742 |
|
|
instead of the standard error. |
743 |
|
|
.TP |
744 |
|
|
.BR \-w |
745 |
|
|
Boolean switch for warning messages. |
746 |
|
|
The default is to print warnings, so the first appearance of |
747 |
|
|
this option turns them off. |
748 |
|
|
.SH EXAMPLE |
749 |
|
|
rpict -vp 10 5 3 -vd 1 -.5 0 scene.oct > scene.pic |
750 |
|
|
.PP |
751 |
|
|
rpict -S 1 -o frame%02d.pic scene.oct < keyframes.vf |
752 |
|
|
.SH ENVIRONMENT |
753 |
|
|
RAYPATH the directories to check for auxiliary files. |
754 |
|
|
.SH FILES |
755 |
|
|
/usr/tmp/rtXXXXXX common header information for picture sequence |
756 |
|
|
.br |
757 |
|
|
rfXXXXXX temporary name for recover file |
758 |
|
|
.SH DIAGNOSTICS |
759 |
|
|
If the program terminates from an input related error, the exit status |
760 |
|
|
will be 1. |
761 |
|
|
A system related error results in an exit status of 2. |
762 |
|
|
If the program receives a signal that is caught, it will exit with a status |
763 |
|
|
of 3. |
764 |
|
|
In each case, an error message will be printed to the standard error, or |
765 |
|
|
to the file designated by the |
766 |
|
|
.I \-e |
767 |
|
|
option. |
768 |
|
|
.SH AUTHOR |
769 |
|
|
Greg Ward |
770 |
|
|
.SH "SEE ALSO" |
771 |
|
|
getinfo(1), lookamb(1), oconv(1), pfilt(1), pinterp(1), pmblur(1), |
772 |
|
|
printf(3), ra_rgbe(1), rad(1), rtrace(1), rview(1) |