NAME

       tachyon-ogl - parallel/multiprocessor ray tracer with OpenGL display

SYNOPSIS

       tachyon-ogl modelfile [options]

DESCRIPTION

       Valid options and accepted formats are as follows (** denotes default behaviour).

   Model file formats supported:
       filename.dat
              the model files originated with this package

       filaname.ac
              AC3D model files

       filename.nff
              the NFF scene format used by Eric Haines' SPD

   Message Options:
       +V     verbose messages on

       -V     verbose messages off **

   Speed Tuning Options:
       -raydepth xxx
              maximum ray recursion depth

       -numthreads xxx
              (** default is auto-determined)

       -nobounding

       -boundthresh xxx
              (** default threshold is 16)

   Shading Options:
       -fullshade
              best quality rendering (and slowest) **

       -mediumshade
              good quality rendering, but no shadows

       -lowshade
              low quality rendering, preview (and fast)

       -lowestshade
              worst quality rendering, preview (and fastest)

   Lighting Options:
       -rescale_lights xxx rescale light intensity values by
              specified factor (performed before other lighting overrides take effect)

       -auto_skylight xxx
              force  use  of  ambient  occlusion lighting, auto-rescaling direct light sources to
              compensate for ambient occlusion factor (use value 0.7 as a good starting point)

       -add_skylight xxx
              force use of ambient occlusion lighting, manually-rescaling direct light sources to
              compensate for ambient occlusion factor

       -skylight_samples xxx number of sample rays to shoot

   Specular Highlight Shading Options:
       -shade_phong
              Phong specular highlights

       -shade_blinn
              Blinn's specular highlights **

       -shade_blinn_fast
              fast approximation to Blinn's highlights

       -shade_nullphong
              disable specular highlights

   Transparency Shading Options:
       -trans_max_surfaces xxx
              limit the number of transparent surfaces shown to the number specified

       -trans_orig
              original implementation **

       -trans_raster3d
              Raster3D angle-based opacity modulation

       -trans_vmd
              opacity post-multiply used by VMD

   Transparent Surface Shadowing Options:
       -shadow_filter_on
              transparent objects cast shadows **

       -shadow_filter_off
              transparent objects do not cast shadows

   Fog Shading Options:
       -fog_radial
              radial fog implementation **

       -fog_vmd
              planar OpenGL-like fog used by VMD

   Surface Normal/Winding Order Fixup Mode:
       -normalfixup [off|flip|guess] (** off is default)

   Antialiasing Options:
       -aasamples xxx
              maximum supersamples taken per pixel (** default is 0, or scene file determined)

   Output Options:
       -res Xres Yres
              override scene-defined output image size

       -o outfile.tga
              set output file name

       -clamp clamp pixel values to [0 to 1) **

       -normalize
              normalize pixel values to [0 to 1)

       -gamma val
              normalize apply gamma correction

       -format BMP
              24-bit Windows BMP (uncompressed)

       -format JPEG
              24-bit JPEG        (compressed, but lossy)

       -format PNG
              24-bit PNG         (compressed, lossless)

       -format PPM
              24-bit PPM         (uncompressed)

       -format PPM48
              48-bit PPM         (uncompressed)

       -format PSD48
              48-bit PSD         (uncompressed)

       -format RGB
              24-bit SGI RGB     (uncompressed)

       -format TARGA
              24-bit Targa       (uncompressed) **

   Animation Related Options:
       -camfile filename.cam
              animate using file of camera positions

       -nosave
              disable writing of output frames to disk (only used for doing real-time rendering)

   Interactive Spaceball/SpaceNavigator Control:
       -spaceball
              enable Spaceball/SpaceNavigator camera flight

       -spaceballport serialportdevicename (only for serial devices)

   Getting Help:
       -help  display help message and exit

       -version
              display version string and exit

       -banner
              display banner and exit