1 .\" 

     2 .TH "LTVIEW" "1" "11/03/14" "RADIANCE" ""

     3 .SH "NAME"

     4 ltview \- view a light source

     5 .SH "SYNOPSIS"

     6 .B ltview

     7 [

     8 .B \-i

     9 ][

    10 .B "\-r roomsize"

    11 ][

    12 .B "\-o output device"

    13 ]

    14 input

    15 .SH "DESCRIPTION"

    16 .I ltview

    17 renders a Radiance luminiare or IES photometry interactively using

    18 .I rad(1)

    19 .  This program is merely a shell script that calls

    20 .I rad(1)

    21 to make an octree and view the scene interactively.

    22 .PP 

    23 .I ltview

    24 accepts exactly one Radiance object or IES photometry

    25 file as input.  No input is taken from STDIN.  The

    26 .I \-i

    27 option tells it that the file name given is 

    28 an IES photometry file rather then a Radiance description of a 

    29 luminiare.  In this case, Radiance's

    30 .I ies2rad(1)

    31 is called with its default settings to convert the IES file into a 

    32 Radiance object.

    33 .PP 

    34 Unlike

    35 .I objpict(1)

    36 or

    37 .I objview(1)

    38 , no additional light sources are added to the scene, since it is

    39 assumed that the object is a luminaire.

    40 .PP 

    41 .I ltview

    42 relies on Radiance's

    43 .I rad(1)

    44 command to compile an octree and to call

    45 .I rvu(1)

    46 to display an interactive preview of the luminaire.

    47 The default behaviour for

    48 .I ltview

    49 is to scale the luminaire or output from 

    50 .I ies2rad(1)

    51 so that the largest dimension of the fitting is unity, centered at the origin.

    52 This scaled representation of the original fitting is then placed inside a 

    53 square box 10 units in size.  The \-y face of the box is left open so that 

    54 the camera can look inside, facing +y.

    55 If it is desirable to keep the original luminaire in both its original size,

    56 and its original location, the

    57 .I "\-r roomsize"

    58 option may be used to fix the room size to a certain

    59 .I roomsize.

    60 In this case, the size and location of the fitting is not adjusted, and

    61 it is up to the user to decide on appropriate room dimensions.  Note that

    62 when

    63 .I \-r

    64 and

    65 .I \-i

    66 are combined, then the dimensions of the luminaire and intesity of its 

    67 output are determined by

    68 .I ies2rad(1)'s

    69 default settings.  If this is not acceptable, then it is best to run

    70 .I ies2rad(1)

    71 manually, and to feed

    72 .I ltview

    73 the hand\-crafted fitting, rather than the IES photometry.

    74 .PP 

    75 The default

    76 .I rvu(1)

    77 output device is

    78 .I x11

    79 on all platforms except for Windows, where it is set to

    80 .I qt.

    81 This may be overwritten with the

    82 .I "\-o output"

    83 option.

    84 

    85 .SH "EXAMPLES"

    86 To query available output devices

    87 .IP "" .2i

    88 rvu \-devices

    89 .PP 

    90 To visualise an IES file with the qt driver

    91 .IP "" .2i

    92 ltview \-o qt ABC123.ies

    93 .PP 

    94 To look at a typical T5 fluorescent fitting that is modelled in millimeters

    95 .IP "" .2i

    96 ltview \-r 5000 XYZ_batten.rad

    97 .SH "AUTHOR"

    98 Axel Jacobs

    99 .SH "SEE ALSO"

   100 ltpict(1), ies2rad(1), oconv(1), rad(1), rvu(1)