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vllight, vlenable, vldisable

NAME

vllight, vlenable, vldisable - Define the light sources and enable/disable them

SYNOPSIS

#include <parvox.h>

    int vllight(int light_num, int parameter, float n0, float n1, float n3)
    int vlenable(int type)
    int vldisable(int type)

DESCRIPTION

vllight() sets the light source parameters. ParVox allows maximal 5 light sources and they are numbered as VL_LIGHT0, VL_LIGHT1, VL_LIGHT2, VL_LIGHT3, an VL_LIGHT4. light_num can be one of the above five numbers. ParVox assumes all the light sources are located in the infinite distace and all the lights are white light. parameter of a given light could be either VL_DIRECTION or VL_COLOR. If it is VL_DIRECTION, (n0, n1, n2) is the direction vector of the selected light source in object coordinates. If it is VL_COLOR, n0 is the intensity of the light (in the range of 0 and 1); n1 and n2 are ignored.

vlenable() and vldisable() enables or disables the lighting model if type is VL_LIGHTING, or a particular light source if type is one of the five light number VL_LIGHTi.

Lighting model is only used for isosurface rendering. Each isourface is assigned a default color and the lighting model based on the Blinn's equation is used to create the shading. For direct volume rendering or slice rendering, the voxel color is solely determined by the color map.

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This page, http://pat.jpl.nasa.gov/public/ParVox/API/vllight.html, is maintained by Peggy Li and was last modified Wednesday, 09-Mar-2005 16:42:35 PST