+ View the NASA Portal

ParVox Library

NAME

intro_parvox - Introduction to the Parallel Voxel (ParVox) Rendering API

IMPLEMENTATION

The SGI Origin 2000, SGI Altix, Linux Cluster

DESCRIPTION

ParVox library is a parallel volume rendering library running on various parallel supercomputers. The ParVox API is written in C and uses the MPI library for interprocessor communication. It consists of a suite of openGL-like functions starting with "vl". The ParVox library is capable of visualization of multiple time-step, multiple variable, 3-D scientific datasets in regular structured grids and unstructured grid represented as tetrahedrons. The volume can be rendered as a transluncent volume, multiple isosurfaces, or multiple slabs or slices.

PARVOX API

ParVox Initialization APIs

        vlinit                 -- ParVox initialization routine
        vlinit_fb            -- Initialization routine for the framebuffer and output devices
        vlread_environ -- Load a predefined environment file and set the rendering parameters

ParVox Low-level APIs

        vlmatrix_mode -- Set the matrix mode to either VL_MODELVIEW or VL_PROJECTION
        vlload_identity -- Load a 4x4 identity matrix to the matrix chosen by vlmatrix_mode()
        vlmult_matrix -- Multiple the current matrix by an input 4x4 matrix
        vlscale               -- Multiple the current matrix by a general scaling matrix
        vltranslate         -- Multiple the current matrix by a tranlation matrix
        vlrotate             -- Multiple the current matrix by a rotation matrix
        vlchange_filter -- Change the splatting filter and its parameters
        vlortho              -- Multiple the current matrix by an orthographic matrix
        vlviewport         -- Set the viewport
        vllook_at           -- Define a viewing transformation

ParVox Input Volume APIs

        vlcreate_volume -- Create a 3-D volume data structure with multiple variables
        vlcopy_volume    -- Copy the meta information of an existing volume to a new volume
        vldelete_volume -- Delete the volume data structure and free up all the memory
        vldelete_variable -- Delete a variable from an existing volume
        vlread_block        -- Read multiple time step input volume files and distribute them into local processor's
                                         volume structure
        vlset_spacing       -- Set the voxel spacing to allow non-cubic voxels
        vlset_range          -- Set the data range of a specific variable

ParVox Classification APIs

        vlpick_iso_color     --   Select the color for the isosurface from the variable's colormap
        vliso_shade             -- Define the iso-surfaces for a specific variable and shade the volume
        vliso_surface          -- Define the iso-surfaces for a specific variable
        vlenable_surface     -- Enable a specific iso-surface for rendering
        vldisable_surface    -- Disable a specific iso-surface for rendering
        vlset_slices             -- Define the slices for a specific variable
        vlset_nodata_color -- Set the color and the value for "nodata" voxels
        vlset_colormap        -- Set the colormap of a given variable
        vlset_opmap            -- Set the opacity map of a given variable

ParVox Lighting/Shading APIs

        vllight                    -- Set the light source direction and color
        vlenable                 -- Enable the lighting model or a light source
        vldisable                 -- Disable the lighting model or a light source
        vlmaterial              -- Set the material property of a specific variable
        vlgradient_shade    -- Calculate the gradient vectors and shade the volume

ParVox Rendering APIs

        vlenable_variable   -- Enable a variable in a given volume for rendering
        vldisable_variable   -- Disable a variable in a given volume for rendering
        vlset_render_type    -- Set the rendering type to VL_VOLUME, VL_SLICE, or VL_ISO
        vlflush                     -- Render the volume and display the image

ParVox Utility APIs

        vlprintf                    -- Print the message to stdout from all the PEs
        vl0printf                    -- Print the message to stdout from PE #0
        vlerror                     -- Print an error message and exit