'\" te
.\" Copyright (c) 2007, Sun Microsystems, Inc.  All Rights Reserved 
.TH mlib_VolumeRayCast_General 3MLIB  "2 Mar 2007" "SunOS 5.11" "mediaLib Library Functions"
.SH NAME
mlib_VolumeRayCast_General, mlib_VolumeRayCast_General_Parallel_Nearest_U8_Bit, mlib_VolumeRayCast_General_Parallel_Nearest_U8_U8, mlib_VolumeRayCast_General_Parallel_Nearest_S16_S16, mlib_VolumeRayCast_General_Parallel_Trilinear_U8_U8, mlib_VolumeRayCast_General_Parallel_Trilinear_S16_S16, mlib_VolumeRayCast_General_Divergent_Nearest_U8_Bit, mlib_VolumeRayCast_General_Divergent_Nearest_U8_U8, mlib_VolumeRayCast_General_Divergent_Nearest_S16_S16, mlib_VolumeRayCast_General_Divergent_Trilinear_U8_U8, mlib_VolumeRayCast_General_Divergent_Trilinear_S16_S16 \- cast a ray (or rays) through a 3D data set
.SH SYNOPSIS
.LP
.nf
cc [ \fIflag\fR... ] \fIfile\fR... \fB-lmlib\fR [ \fIlibrary\fR... ]
#include <mlib.h>

\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Parallel_Nearest_U8_Bit\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Parallel_Nearest_U8_U8\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Parallel_Nearest_S16_S16\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Parallel_Trilinear_U8_U8\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Parallel_Trilinear_S16_S16\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Divergent_Nearest_U8_Bit\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Divergent_Nearest_U8_U8\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Divergent_Nearest_S16_S16\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Divergent_Trilinear_U8_U8\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_VolumeRayCast_General_Divergent_Trilinear_S16_S16\fR(
     \fBmlib_rays *\fR\fIrays\fR, \fBconst mlib_genvolume *\fR\fIvol\fR, \fBvoid *\fR\fIbuffer\fR);
.fi

.SH DESCRIPTION
.sp
.LP
Each of these functions casts a ray (or rays) through a three-dimensional (3D) data set, then computes and returns the interpolated samples at each step along the way.
.sp
.LP
In trilinear interpolation, the value at point P is computed from its eight surrounding neighbors based on the equation below.
.sp
.in +2
.nf
P = (1-a)*(1-b)*(1-c)*P0 +
    a*(1-b)*(1-c)*Px + (1-a)*b*(1-c)*Py + (1-a)*(1-b)*c*Pz +
    a*b*(1-c)*Pxy + a*(1-b)*c*Pxz + (1-a)*b*c*Pyz +
    a*b*c*Pxyz
.fi
.in -2

.sp
.LP
where a, b, and c are the fractional parts of the coordinates of point P.
.sp
.LP
The trilinear interpolation is represented by the following figure:
.sp
The printed copy and the Oracle Technology Network version of this manual page display a figure that represents the trilinear interpolation.
.sp
.LP
In nearest neighbor operation, the sample value at point P is replaced by the value of the nearest neighbor voxel.
.SH PARAMETERS
.sp
.LP
Each of the functions takes the following arguments:
.sp
.ne 2
.mk
.na
\fB\fIrays\fR\fR
.ad
.RS 10n
.rt  
Casting rays.
.RE

.sp
.ne 2
.mk
.na
\fB\fIvol\fR\fR
.ad
.RS 10n
.rt  
Volume data that consists of slices.
.RE

.sp
.ne 2
.mk
.na
\fB\fIbuffer\fR\fR
.ad
.RS 10n
.rt  
Working buffer.
.RE

.SH RETURN VALUES
.sp
.LP
Each of the functions returns \fBMLIB_SUCCESS\fR if successful. Otherwise it returns \fBMLIB_FAILURE\fR.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityCommitted
_
MT-LevelMT-Safe
.TE

.SH SEE ALSO
.sp
.LP
\fBmlib_VolumeRayCast_Blocked\fR(3MLIB), \fBattributes\fR(5)