detail expression function
Returns the value of a detail attribute.
detailattribsize expression function
Returns the number of components in a detail attribute.
details expression function
Returns the string value of a detail attribute.
detailsmap expression function
Returns a string from a list of strings in a detail attribute.
detailsnummap expression function
Returns the number of unique stings bound to a detail attribute.
hasdetailattrib expression function
Returns 1 if a specified detail attribute exists.
haspointattrib expression function
Returns 1 if a specified point attribute exists.
hasprimattrib expression function
Returns 1 if a specified primtive attribute exists.
hasvertexattrib expression function
Returns 1 if a specified vertex attribute exists.
point expression function
Returns the value of a point attribute.
pointattribsize expression function
Returns the number of components in a point attribute.
primattribsize expression function
Returns the number of components in a primitive attribute.
vertexattribsize expression function
Returns the number of components in a vertex attribute.
chexist expression function
Returns 1 if the specified channel exists, 0 if it doesn’t.
chgroup expression function
return a string containing all of the channels contained in a group.
chopcf expression function
Evaluates a channel within a CHOP at a given time.
chopci expression function
Evaluates a channel within a CHOP at a specified sample point.
boneangle expression function
Returns the angle at the joint between two bone objects.
objkinoverride expression function
Returns the current global kinematic override setting for bone objects.
Evaluates a channel within a CHOP at the current time.
chopct expression function
Evaluates a channel within a CHOP at a specified time.
chope expression function
Returns the end index of the channels in a CHOP.
chopf expression function
Evaluates a channel within a CHOP with at a given frame.
chopi expression function
Evaluates a channel within a CHOP at a given sample point.
chopl expression function
Returns the length of the channels in a CHOP, in samples.
chopn expression function
Returns the number of data channels within a CHOP.
chopr expression function
Returns the sample rate of a CHOP.
chops expression function
Returns the start index of a CHOP.
chopstr expression function
Returns the string value of a channel within a CHOP at the current time.
chopt expression function
Returns the value of a channel within a CHOP at a specified time.
Evaluates a CHOP’s input channel at a specific index.
Returns the end index of a CHOP’s input.
Returns the length of a CHOP’s input, in samples.
icmax expression function
Evaluates a CHOP’s input channel’s maximum value.
icmin expression function
Evaluates a CHOP’s input channel’s minimum value.
Returns the number of channels in a CHOP’s input.
Returns the sample rate of a CHOP’s input.
Returns the start index of a CHOP’s input.
Returns the value of a CHOP’s output at a specific sample index.
Converts RGB values to HSV components.
Converts HSV values to RGB components.
dopallfields expression function
Returns a space separated list of all the field names that can be passed to the dopfield function.
dopfield expression function
Returns the value of a field as a float.
dopfieldname expression function
Returns the name of a DOP field.
dopfields expression function
Returns the value of a DOP field as a string.
dopfieldtype expression function
Returns the type of a DOP field.
dopframe expression function
Returns the current frame of the simulation.
dopframetost expression function
Returns the simulation time equivalent of a simulation frame.
dopgrouphasobject expression function
Returns 1 if a specified DOP group contains a specified object.
dopgroupismutual expression function
Returns 1 if a specified DOP group is mutually affecting.
dopgrouplist expression function
returns a string containing a list of all object groups for the current time in a specified DOP Network.
dophasfield expression function
Returns 1 if a specified DOP field exists.
dophassubdata expression function
Returns 1 if a dynamics object has the specified subdata.
dopnodeobjs expression function
Returns the list of objects processed by a DOP in the latest timestep.
dopnumfields expression function
Returns the number of fields in a DOP record type.
dopnumobjects expression function
returns the number of objects in a simulation.
dopnumrecords expression function
Returns the number of records of a given type in a piece of dynamics data.
dopnumrecordtypes expression function
Returns the number of types of record in a piece of dynamics data.
dopnumsubdata expression function
Returns the number of subdata items attached to an object or data.
dopobjectlist expression function
Returns all objects matching the an object specification.
Tests whether a set of objects has an affector relationship with another object.
dopoption expression function
Returns the value of a DOP field as a float.
dopoptions expression function
Returns the value of a DOP field as a string.
doprecordtypename expression function
Returns the name of a record in DOPs data given its index.
dopsolvedopnet expression function
Script solver support function.
dopsolvenumobjects expression function
Script solver support function.
dopsolveobject expression function
Script solver support function.
dopsolvetimestep expression function
Script solver support function.
dopsttoframe expression function
returns the simulation frame of a given simulation time.
dopsttot expression function
Returns the global time of a given simulation time.
dopsubdataname expression function
Returns the name of a subdata of a given DOP object.
doptime expression function
Returns the current time of a simulation.
doptransform expression function
Returns a transformation matrix associated with a piece of data.
dopttost expression function
Returns the simulation time equivalent to a given global time.
dopvelatpos expression function
Returns the velocity that a point at a location in simulation space would have if it were attached to a DOP object.
seampoints expression function
Lists all seam points in a surface node.
findfile expression function
Searches the Houdini path for a file.
findfiles expression function
Searches the Houdini path for a file or directory.
Returns bounding box information for a surface node.
centroid expression function
Returns centroid information for a surface node.
curvature expression function
Returns the curvature of the surface at the given UV coordinates.
degree expression function
Returns the degree a specified face or hull.
distance expression function
Returns the distance between two 3D points.
haspoint expression function
Returns 1 if a specified point is in a specified group.
hasprim expression function
Returns 1 if a specified primitive is in a specified group.
isclosed expression function
Returns 1 if a primitive is closed.
iscollided expression function
Returns 1 if a specified point has collided with something.
isspline expression function
Returns 1 if a specified primitive is a NURBs or Bezier curve or surface.
isstuck expression function
Returns 1 if a specified point is a stuck particle.
iswrapu expression function
Returns 1 if a specified primitive is wrapped in U.
iswrapv expression function
Returns 1 if a specified primitive is wrapped in V.
metaweight expression function
Returns the weight of a metaball at a specific location.
mindist expression function
Finds the smallest distance between a point and a primitive.
nearpoint expression function
Finds the point in a geometry nearest to specific 3D coordinates.
normal expression function
Returns the components of the surface normal specific UV coordinates.
npoints expression function
Returns the number of points in a geometry.
nprims expression function
Returns the number of primitives in a surface node.
pointavg expression function
Returns the average of an attribute across all points in a geometry.
pointdist expression function
Returns the distance between a point and a primitive.
pointgrouplist expression function
Returns the list of point groups in a surface node.
pointgroupmask expression function
Returns the list of point groups matching a pattern in a surface node.
pointlist expression function
Returns a list of all points in a point group.
pointneighbours expression function
Lists points that share a minimum number of primitives with a specified point.
pointpattern expression function
Returns a list of points that match a specified pattern.
points expression function
Returns the string value of a point attribute.
pointsmap expression function
Returns a string from a list of strings in a point attribute.
pointsnummap expression function
Returns the number of unique strings bound to a point attribute.
Returns the value of a primitive attribute.
primdist expression function
Returns the minimum distance and closest points between two primitives.
primduv expression function
Returns the partial derivatives of a primitive attribute.
primgrouplist expression function
Returns the list of primitive groups in a surface node.
primgroupmask expression function
Returns the list of groups matching a pattern in a surface node.
primlist expression function
Returns a list of all primtives in a surface node.
primneighbours expression function
Lists primitives that share a minimum number of points with a specified primitive.
prims expression function
Returns the string value of a primitive attribute.
primsmap expression function
Returns a string from a list of strings in a primitive attribute.
primsnummap expression function
Returns the number of unique strings bound to a primitive attribute.
primuv expression function
Returns the value of a primitive attribute at a certain UV location.
realuv expression function
Converts unit UV to real UV.
spknot expression function
Returns a knot value on a spline curve or surface.
surflen expression function
Returns the length of the 3D curve between two points on a surface.
unituv expression function
Converts real UV to unit UV.
uvdist expression function
Returns the distance between parameteric locations on two primitives.
vertex expression function
Returns the value of a vertex attribute.
vertexs expression function
Returns the string value of a vertex attribute.
vertexsmap expression function
Returns a string from a list of strings in a vertex attribute.
vertexsnummap expression function
Returns the number of unique strings bound to a point attribute.
xyzdist expression function
Returns the distance between a 3D coordinate and a primitive.
Returns the color of a pixel in a compositing node.
picni expression function
Returns the non-interpolated color of a pixel in a compositing node.
Returns the natural resolution of the image in a compositing node.
seqanim expression function
Returns 1 if a specified compositing node has an animated sequence.
seqend expression function
Returns the end frame of a compositing node’s image sequence.
seqlength expression function
Returns the number of frames in a compositing node’s image sequence.
seqstart expression function
Returns the start frame of a compositing node’s image sequence.
Returns the interpolated color of a point on an on-disk texture map.
texni expression function
Returns the non-interpolated color of a point on an on-disk texture map.
mousepane expression function
Returns the full name of the pane currently under the mouse pointer.
mousepath expression function
Returns the node path of the pane currently under the mouse pointer.
vpname expression function
Takes a viewer name and a viewport number and returns the viewport’s name.
Returns the absolute value of the argument.
Returns the arc-cosine of the argument.
arclen expression function
Returns the arc length of a curve between two U positions.
Returns the arc-sine of the argument.
Returns the arc-tangent of the argument.
atan2 expression function
Returns the arc-tangent of y/x.
Returns the smallest integer not less than the value passed in.
clamp expression function
Returns a value clamped between a minimum and maximum.
Returns the cosine of the argument.
Returns the hyperbolic cosine of the argument.
Converts from radians to degrees.
Returns the logarithmic exponentiation of the argument.
Fits a value from one range to another.
fit01 expression function
Fits a value to the 0-1 range.
fit10 expression function
Fits a number in the 0-1 range.
fit11 expression function
Fits a number to the -1 to 1 range.
floor expression function
Returns the largest integer not greater than a number.
Returns the fractional part of a floating-point number.
Converts a number to an integer by truncating any fractional part.
Returns the natural logarithm of the argument.
log10 expression function
Returns the base 10 logarithm of the argument.
Returns the larger of two values.
Returns the smaller of two values.
modblend expression function
Blends the two modular values.
Raises a number to an exponent.
Converts from degrees to radians.
Rounds to the nearest integer.
round expression function
Rounds a number to the nearest integer.
Returns -1, 0, or 1 depending on the sign of the argument.
Returns the sine of the argument.
Returns the hyperbolic sine of the argument.
smooth expression function
Taks a value and range and returns a smooth interpolation between 0 and 1.
Returns the square root of the argument.
Returns the tangent of the argument.
Returns the hyperbolic tangent of the argument.
trunc expression function
Converts a number to an integer by truncating any fractional part, rounding towards 0.
Wraps a value between a minimum and maximum.
determinant expression function
Returns the determinant of a matrix.
dihedral expression function
Computes the dihedral matrix between vectors v0 and v1.
explodematrix expression function
Explodes a 3×3 or 4×4 matrix into the euler rotations required to rebuild it.
explodematrixp expression function
Explodes a 3×3 or 4×4 matrix into the euler rotations required to rebuild it.
identity expression function
Creates an identity matrix.
invert expression function
Inverts a matrix.
matrix expression function
Converts a string specification into a matrix.
matrixtoquat expression function
Converts a rotation matrix to a quaternion.
mcols expression function
Returns the number of columns in a matrix.
mlookat expression function
Computes the transformation matrix of a lookat from one vector to another.
mlookatup expression function
Computes the transformation matrix of a lookat from one vector to another, with an up vector.
mobjlookat expression function
Computes the transformation matrix of a lookat from one object to another.
morient expression function
Computes the transformation matrix to orient along specific Z and Y axes.
mrows expression function
Returns the number of rows in a matrix.
mzero expression function
Returns a matrix with all values set to 0.
quattomatrix expression function
Converts quaternion to a 3×3 rotation matrix.
rotate expression function
Returns a 4×4 rotation matrix from an axis and angle.
rotaxis expression function
Returns a 4×4 rotation matrix from an angle and a vector.
scale expression function
Takes three scaling values and returns a scale matrix.
translate expression function
Takes X, Y, and Z translation values and returns a translation matrix.
transpose expression function
Transposes a matrix.
opdigits expression function
Returns the numeric suffix of a node name.
opexist expression function
Returns 1 if the specified node, group, or bundle exists.
opflag expression function
Returns a list nodes with a particular flag set.
opfullpath expression function
Returns the full path of a node.
opfullpathfrom expression function
Returns the path of a node relative to another node.
Returns the unique ID of a node.
opinput expression function
Returns the name of the node connected to a given input.
opinputpath expression function
Returns the full path of the node connected to a given input.
opisloading expression function
Returns 1 if Houdini is currently loading a scene file.
opname expression function
Returns the name of a node given its path.
opnchildren expression function
Returns the number of nodes inside a container node.
opninputs expression function
Returns the maximum number of connected inputs.
opnoutputs expression function
Returns the number of nodes connected to a node’s output.
opoutput expression function
Returns the name of a node connected a given node’s output.
opoutputpath expression function
Returns the full path of a node connected a given node’s output.
oprelativepath expression function
Returns the relative path from one node to another.
opselect expression function
Returns a list of the selected nodes.
opselectrecurse expression function
Returns a recursive list of the selected nodes.
opsubpath expression function
Returns the full path of a node including any containing subnets.
optype expression function
Returns the type of a node.
optypeinfo expression function
Returns type information about a node.
objlightmask expression function
Returns a list of lights matching an object’s light mask.
objlookat expression function
Computes the rotation vector of a lookat from one object to another.
objpretransform expression function
Returns an object’s pre-transform matrix.
opblist expression function
Returns the full paths of all operators in a bundle.
oplightmask expression function
Returns a list of lights matching an object’s light mask.
optransform expression function
Returns the transformation matrix of an object at the current time.
origin expression function
Returns components of an object’s transforms.
originoffset expression function
Returns components of an object’s offset transforms.
cucwc expression function
Deprecated: current working container for custom panels.
cudatatype expression function
Deprecated: data type of a gadget, for custom panels.
cumenuadd expression function
Deprecated: adds a menu entry on a custom panel.
cuquery expression function
Deprecated: returns a value from a custom panel.
cutype expression function
Deprecated: Returns the type of a gadget on a custom panel.
oppinput expression function
Deprecated: replaced by opinput.
param expression function
Deprecated: use stamp instead.
Returns the value of a parameter.
Evaluates a parameter at a given frame.
Evaluates the string value of a parameter at the current time.
chsop expression function
Evaluates the parameter at the current time as a node path string.
chsraw expression function
Returns the raw expression value of a parameter as a string.
Returns the value of a parameter at a specified time.
parmisstring expression function
Returns 1 if a specified parameter is a string.
stamp expression function
Returns a copy stamping floating point value.
stamps expression function
Returns a copy stamping string value.
popcontextgeo expression function
Returns the full path to a particle network context geometry.
popevent expression function
Returns 1 if a particle event is occurring.
popeventtime expression function
Returns the time of a particle event.
poppoint expression function
Returns the value of a particle attribute, by particle number.
poppointid expression function
Returns the value of a particle attribute, by particle ID.
poppointnum expression function
Returns the point number of the particle with the specified ID.
noise expression function
Generates 3D noise.
oldrand expression function
Returns a pseudo-random number between 0 and 1.
Returns a pseudo-random number from 0 to 1.
snoise expression function
Generates sparse convolution 3D noise.
sturb expression function
Generates spatially coherent 3D noise based on sparse convolution.
Generates spatially coherent 3D noise.
iprquery expression function
Queries numeric (floating point) data from an interactive render pane.
iprquerys expression function
Queries textual (string) data from an interactive render pane.
shopstring expression function
Returns the shader string generated by a shader.
bezier expression function
Channel segment function: Bezier interpoloation spline
constant expression function
Channel segment function: constant value.
cubic expression function
Channel segment function: cubic spline.
cycle expression function
Channel segment function: repeats the animation between frames f1 and f2.
cyclet expression function
Channel segment function: repeats the animation between times t1 and t2.
Channel segment function: ease-in and -out.
easein expression function
Channel segment function: ease-in.
easeinp expression function
Channel segment function: ease-in with configurable acceleration.
easeout expression function
Channel segment function: ease-out
easeoutp expression function
Channel segment function: ease-out with configurable acceleration.
easep expression function
Channel segment function: ease-in and -out with configurable acceleration.
linear expression function
Channel segment function: linear interpolation.
match expression function
Channel segment function: matches the incoming and outgoing slopes.
matchin expression function
Channel segment function: matches the incoming slope.
matchout expression function
Channel segment function: matches the outgoing slope.
qlinear expression function
Channel segment function: uses quaternions to interpolate.
quintic expression function
Channel segment function: smoothly interpolates slopes and accelerations.
Channel segment function.
repeat expression function
Channel segment function: repeats animation from previous frames.
repeatt expression function
Channel segment function: repeats animation from previous frames.
spline expression function
Channel segment
