SYNOPSIS

#include <volpack.h>

vpResult

vpGeti(vpc, option, iptr)

vpContext *vpc;

int option;

int *iptr;

vpResult

vpGetd(vpc, option, dptr)

vpContext *vpc;

int option;

double *dptr;

vpResult

vpGetp(vpc, option, pptr)

vpContext *vpc;

int option;

void *pptr;

ARGUMENTS

vpc

VolPack context from vpCreateContext.

option

Constant that specifies the option to be retrieved.

iptr

Location to store an integer result.

dptr

Location to store a double result.

pptr

Location to store a pointer result.

DESCRIPTION

These functions are used the get the values of integer-, double- or pointer-valued state variables in a rendering context. The following list summarizes the integer-valued options that can be retrieved with vpGeti. The value of the option is stored in the location given by iptr; the return value of vpGeti is not the value of the option. Unless otherwise noted, the result is a single integer and iptr should point to a single integer location.

VP_XLEN

Get the length of the X dimension of the volume in voxels.

VP_YLEN

Get the length of the Y dimension of the volume in voxels.

VP_ZLEN

Get the length of the Y dimension of the volume in voxels.

VP_BYTES_PER_VOXEL

Get the size of a voxel in bytes.

VP_VOXEL_FIELD_COUNT

Get the number of fields in a voxel.

VP_SHADE_FIELD_COUNT

Get the number of fields in a voxel used as parameters for shading the voxel.

VP_FIELD_SIZES

Get the size of each voxel field in bytes. iptr must point to an array of integers containing one entry for each voxel field (use VP_VOXEL_FIELD_COUNT to determine the number of fields).

VP_FIELD_OFFSETS

Get the byte offset from the beginning of a voxel for each voxel field. iptr must point to an array of integers containing one entry for each voxel field (use VP_VOXEL_FIELD_COUNT to determine the number of fields).

VP_FIELD_MAXES

Get the maximum value of the quantity stored in each voxel field. iptr must point to an array of integers containing one entry for each voxel field (use VP_VOXEL_FIELD_COUNT to determine the number of fields).

VP_VOXEL_DATA_SIZE

Get the size (in bytes) of the 3D voxel array.

VP_VOXEL_XSTRIDE

Get the stride (in bytes) for the X dimension of the 3D voxel array.

VP_VOXEL_YSTRIDE

Get the stride (in bytes) for the Y dimension of the 3D voxel array.

VP_VOXEL_ZSTRIDE

Get the stride (in bytes) for the Z dimension of the 3D voxel array.

VP_CLASSIFY_FIELD_COUNT

Get the number of fields in a voxel used as parameters for classifying the voxel (the number of arguments to the opacity transfer function).

VP_CLASSIFY_FIELDS

Get the field numbers for the arguments to the opacity transfer function. iptr must point to an array of integers containing one entry for each argument (use VP_CLASSIFY_FIELD_COUNT to determine the number of arguments).

VP_CLASSIFY_TABLE_SIZES

Get the size (in bytes) of each lookup table used for the opacity transfer function. iptr must point to an array of integers containing one entry for each lookup table (use VP_CLASSIFY_FIELD_COUNT to determine the number of lookup tables, which equals the number of arguments to the opacity transfer function).

VP_COLOR_CHANNELS

Get the number of color channels that the current shading lookup tables or shading callback function will produce.

VP_SHADE_COLOR_SIZE

Get the size of the shading lookup table for color values (see vpSetLookupShader(3)).

VP_SHADE_WEIGHT_SIZE

Get the size of the shading lookup table for weight values (see vpSetLookupShader(3)).

VP_MATERIAL_COUNT

Get the number of material types used by the current lookup shader (see vpSetLookupShader(3)).

VP_SHADE_COLOR_FIELD

Get the field number used for indexing the shading lookup table for color values (see vpSetLookupShader(3)).

VP_SHADE_WEIGHT_FIELD

Get the field number used for indexing the shading lookup table for weight values (see vpSetLookupShader(3)).

VP_LIGHT0

VP_LIGHT1

VP_LIGHT2

VP_LIGHT3

VP_LIGHT4

VP_LIGHT5

The retrieved value is nonzero if the corresponding light is enabled, or 0 if it is disabled.

VP_LIGHT_BOTH_SIDES

The retrieved value is nonzero if two-sided lighting is enabled (see vpSetLight(3)), or 0 if it is disabled.

VP_REVERSE_SURFACE_SIDES

The retrieved value is nonzero if the definitions of interior and exterior surfaces have been reversed (see vpSetMaterial(3)), or 0 if they have not.

VP_DEPTH_CUE

The retrieved value is nonzero if depth cueing is enabled, or 0 if it is disabled.

VP_DEPTH_CUE_TABLE_SIZE

Get the current number of entries in the depth cueing table (see vpSetDepthCueing(3)).

VP_DEPTH_CUE_SIZE_HINT

Get the current hint for the number of entries in the depth cueing table (see vpSetDepthCueing(3)).

VP_CURRENT_MATRIX

Get the identifier for the current transformation matrix (VP_MODEL, VP_VIEW or VP_PROJECT).

VP_CONCAT_MODE

Get the identifier for the current matrix concatenation mode (VP_CONCAT_LEFT or VP_CONCAT_RIGHT).

VP_IMAGE_WIDTH

Get the width (in pixels) of the output image array.

VP_IMAGE_HEIGHT

Get the height (in pixels) of the output image array.

VP_IMAGE_SCAN_SIZE

Get the number bytes per scanline in the output image array.

VP_VIEW_AXIS

Get the identifier for the current major viewing axis in the object coordinate system (VP_X_AXIS, VP_Y_AXIS or VP_Z_AXIS). The axis depends on the viewing transformation.

VP_INTERMEDIATE_WIDTH

Get the width (in pixels) of the intermediate image required to render the current volume with the current viewing transformation (see vpRenderRawVolume(3)).

VP_INTERMEDIATE_HEIGHT

Get the height (in pixels) of the intermediate image required to render the current volume with the current viewing transformation (see vpRenderRawVolume(3)).

VP_INTERMEDIATE_COLOR

Get the number of color channels in the intermediate image (see vpRenderRawVolume(3)).

VP_INT_WIDTH_HINT

Get the current hint for the width (in pixels) of the intermediate image (see vpRenderRawVolume(3)).

VP_INT_HEIGHT_HINT

Get the current hint for the height (in pixels) of the intermediate image (see vpRenderRawVolume(3)).

VP_VIEW_X_AXIS

VP_VIEW_Y_AXIS

VP_VIEW_Z_AXIS

The retrieved value is non-zero if computing a preclassified volume for the corresponding major viewing axis is enabled (see vpClassifyVolume(3)).

VP_VIEW_X_SIZE

VP_VIEW_Y_SIZE

VP_VIEW_Z_SIZE

Get the size (in bytes) of the preclassified volume for the corresponding major viewing axis.

VP_MMOCTREE_THRESHOLDS

Get the current min-max octree range thresholds. iptr must point to an array of integers containing one entry for each threshold (use VP_CLASSIFY_FIELD_COUNT to determine the number of thresholds, which equals the number of arguments to the opacity transfer function).

VP_MMOCTREE_SIZE

Get the size (in bytes) of the min-max octree.

VP_SHADOW

The retrieved value is nonzero if shadows are enabled (see vpSetShadowLookupShader(3)).

VP_SHADOW_LIGHT

Get the constant (e.g. VP_LIGHT0) associated with the current shadow light (see vpSetShadowLookupShader(3)).

VP_SHADOW_WIDTH_HINT

Get the current hint for the width (in pixels) of the shadow buffer (see vpSetShadowLookupShader(3)).

VP_SHADOW_HEIGHT_HINT

Get the current hint for the height (in pixels) of the shadow buffer (see vpSetShadowLookupShader(3)).

VP_SHADOW_COLOR_SIZE

Get the size of the shading lookup table for shadowed color values (see vpSetShadowLookupShader(3)).

VP_SHADOW_BIAS

Get the current shadow bias value (see vpSetShadowLookupShader(3)).

VP_PIXEL_TYPE

Get the current image pixel type (see vpSetImage(3)).

VP_CLAMP_SHADE_TABLE

The retrieved value is nonzero if clamping is enabled for shade table entries, or 0 if it is disabled (see vpShadeTable(3)).

VP_COMPOSITE_ORDER

This value is used for debugging only. It returns 1 if the current major viewing axis (VP_VIEW_AXIS) points in the same direction as the viewing direction, or -1 if they point in opposite directions.

The following list summarizes the double-valued options that can be retrieved with vpGetd. The result is always a single double and dptr should point to a single double location.

VP_MIN_VOXEL_OPACITY

Get the minimum opacity threshold (see vpSeti(3)).

VP_DEPTH_CUE_FRONT

Get the front depth cueing factor (see vpSetDepthCueing(3)).

VP_DEPTH_CUE_DENSITY

Get the depth cueing density (see vpSetDepthCueing(3)).

VP_DEPTH_CUE_QUANTIZATION

Get the depth cueing quantization (see vpSetDepthCueing(3)).

VP_MAX_RAY_OPACITY

Get the maximum opacity threshold (see vpSeti(3)).

The following list summarizes the pointer-valued options that can be retrieved with vpGetp. Unless otherwise noted, the result is a single pointer and pptr should point to a single pointer location.

VP_VOXEL_DATA

Get a pointer to the 3D voxel array.

VP_CLASSIFY_TABLES

Get pointers to each of the lookup tables for the opacity transfer function. pptr must point to an array of pointers containing one entry for each table (use VP_CLASSIFY_FIELD_COUNT to determine the number of tables, which is equal to the number of arguments to the opacity transfer function).

VP_SHADE_FUNC

Get the shading callback function (see vpSetLookupShader(3)).

VP_SHADE_COLOR_TABLE

Get a pointer to the shading lookup table for colors (see vpSetLookupShader(3)).

VP_SHADE_WEIGHT_TABLE

Get a pointer to the shading lookup table for weights (see vpSetLookupShader(3)).

VP_IMAGE

Get a pointer to the output image array (see vpSetImage(3)).

VP_LOG_ALLOC_FUNC

Get a pointer to the memory allocator logging function (see vpSetCallback(3)).

VP_LOG_FREE_FUNC

Get a pointer to the memory deallocator logging function (see vpSetCallback(3)).

VP_STATUS_FUNC

Get a pointer to the status reporting function (see vpSetCallback(3)).

VP_READ_FUNC

Get a pointer to the file I/O read function (see vpSetCallback(3)).

VP_WRITE_FUNC

Get a pointer to the file I/O write function (see vpSetCallback(3)).

VP_MMAP_FUNC

Get a pointer to the file I/O memory mapping function (see vpSetCallback(3)).

VP_CLIENT_DATA

Get a pointer to the client data (see vpSetClientData(3)).

VP_SHADOW_COLOR_TABLE

Get a pointer to the shading lookup table for shadowed color values (see vpSetShadowLookupShader(3)).