Functions
HAPI_DECL	HAPI_GetDisplayGeoInfo (const HAPI_Session session, HAPI_NodeId object_node_id, HAPI_GeoInfo geo_info)
	Get the display geo (SOP) node inside an Object node. If there there are multiple display SOP nodes, only the first one is returned. If the node is a display SOP itself, even if a network, it will return its own geo info. If the node is a SOP but not a network and not the display SOP, this function will fail. More...

HAPI_DECL	HAPI_GetOutputGeoCount (const HAPI_Session session, HAPI_NodeId node_id, int count)
	A helper method that gets the number of main geometry outputs inside an Object node or SOP node. If the node is an Object node, this method will return the cumulative number of geometry outputs for all geometry nodes that it contains. When searching for output geometry, this method will only consider subnetworks that have their display flag enabled. More...

HAPI_DECL	HAPI_GetOutputGeoInfos (const HAPI_Session session, HAPI_NodeId node_id, HAPI_GeoInfo geo_infos_array, int count)
	Gets the geometry info structs (HAPI_GeoInfo) for a node's main geometry outputs. This method can only be called after HAPI_GetOutputGeoCount() has been called with the same node id. More...

HAPI_DECL	HAPI_GetGeoInfo (const HAPI_Session session, HAPI_NodeId node_id, HAPI_GeoInfo geo_info)
	Get the geometry info struct (HAPI_GeoInfo) on a SOP node. More...

HAPI_DECL	HAPI_GetPartInfo (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, HAPI_PartInfo part_info)
	Get a particular part info struct. More...

HAPI_DECL	HAPI_GetEdgeCountOfEdgeGroup (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, const char group_name, int *edge_count)
	Gets the number of edges that belong to an edge group on a geometry part. More...

HAPI_DECL	HAPI_GetFaceCounts (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, int face_counts_array, int start, int length)
	Get the array of faces where the nth integer in the array is the number of vertices the nth face has. More...

HAPI_DECL	HAPI_GetVertexList (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, int vertex_list_array, int start, int length)
	Get array containing the vertex-point associations where the ith element in the array is the point index the ith vertex associates with. More...

HAPI_DECL	HAPI_GetGroupNames (const HAPI_Session session, HAPI_NodeId node_id, HAPI_GroupType group_type, HAPI_StringHandle group_names_array, int group_count)
	Get group names for an entire geo. Please note that this function is NOT per-part, but it is per-geo. The companion function HAPI_GetGroupMembership() IS per-part. Also keep in mind that the name string handles are only valid until the next time this function is called. More...

HAPI_DECL	HAPI_GetGroupMembership (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, HAPI_GroupType group_type, const char group_name, HAPI_Bool membership_array_all_equal, int membership_array, int start, int length)
	Get group membership. More...

HAPI_DECL	HAPI_GetGroupCountOnPackedInstancePart (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, int pointGroupCount, int *primitiveGroupCount)
	Get group counts for a specific packed instanced part. More...

HAPI_DECL	HAPI_GetGroupNamesOnPackedInstancePart (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, HAPI_GroupType group_type, HAPI_StringHandle group_names_array, int group_count)
	Get the group names for a packed instance part This functions allows you to get the group name for a specific packed primitive part. Keep in mind that the name string handles are only valid until the next time this function is called. More...

HAPI_DECL	HAPI_GetGroupMembershipOnPackedInstancePart (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, HAPI_GroupType group_type, const char group_name, HAPI_Bool membership_array_all_equal, int membership_array, int start, int length)
	Get group membership for a packed instance part This functions allows you to get the group membership for a specific packed primitive part. More...

HAPI_DECL	HAPI_GetInstancedPartIds (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, HAPI_PartId instanced_parts_array, int start, int length)
	Get the part ids that this instancer part is instancing. More...

HAPI_DECL	HAPI_GetInstancerPartTransforms (const HAPI_Session session, HAPI_NodeId node_id, HAPI_PartId part_id, HAPI_RSTOrder rst_order, HAPI_Transform transforms_array, int start, int length)
	Get the instancer part's list of transforms on which to instance the instanced parts you got from HAPI_GetInstancedPartIds(). More...

Detailed Description

Functions for reading Geometry (SOP) data

Function Documentation

HAPI_DECL HAPI_GetDisplayGeoInfo	(	const HAPI_Session *	session,
		HAPI_NodeId	object_node_id,
		HAPI_GeoInfo *	geo_info
	)

Get the display geo (SOP) node inside an Object node. If there there are multiple display SOP nodes, only the first one is returned. If the node is a display SOP itself, even if a network, it will return its own geo info. If the node is a SOP but not a network and not the display SOP, this function will fail.

The above implies that you can safely call this function on both OBJ and SOP asset nodes and get the same (equivalent) geometry display node back. SOP asset nodes will simply return themselves.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	object_node_id	The object node id.
[out]	geo_info	HAPI_GeoInfo return value.

HAPI_DECL HAPI_GetEdgeCountOfEdgeGroup	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		const char *	group_name,
		int *	edge_count
	)

Gets the number of edges that belong to an edge group on a geometry part.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The SOP node id.
[in]	part_id	The part id.
[in]	group_name	The name of the edge group.
[out]	edge_count	The number of edges that belong to the group.

HAPI_DECL HAPI_GetFaceCounts	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		int *	face_counts_array,
		int	start,
		int	length
	)

Get the array of faces where the nth integer in the array is the number of vertices the nth face has.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	part_id	The part id.
[out]	face_counts_array	An integer array at least the size of length.
[in]	start	First index of range. Must be at least 0 and at most HAPI_PartInfo::faceCount - 1.
[in]	length	Must be at least 0 and at most HAPI_PartInfo::faceCount - `start`.

HAPI_DECL HAPI_GetGeoInfo	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_GeoInfo *	geo_info
	)

Get the geometry info struct (HAPI_GeoInfo) on a SOP node.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[out]	geo_info	HAPI_GeoInfo return value.

HAPI_DECL HAPI_GetGroupCountOnPackedInstancePart	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		int *	pointGroupCount,
		int *	primitiveGroupCount
	)

Get group counts for a specific packed instanced part.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	part_id	The part id. (should be a packed primitive)
[out]	pointGroupCount	Number of point groups on the packed instance part. Will be set to -1 if the part is not a valid packed part.
[out]	primitiveGroupCount	Number of primitive groups on the instanced part. Will be set to -1 if the part is not a valid instancer

HAPI_DECL HAPI_GetGroupMembership	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		HAPI_GroupType	group_type,
		const char *	group_name,
		HAPI_Bool *	membership_array_all_equal,
		int *	membership_array,
		int	start,
		int	length
	)

Get group membership.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	part_id	The part id.
[in]	group_type	The group type.
[in]	group_name	The group name.
[out]	membership_array_all_equal	(optional) Quick way to determine if all items are in the given group or all items our not in the group. If you do not need this information or you are getting edge group information, you can just pass NULL for this argument.
[out]	membership_array	Array of ints that represent the membership of this group. When getting membership information for a point or primitive group, the size of the array should be the size given by HAPI_PartInfo_GetElementCountByGroupType() with `group_type` and the HAPI_PartInfo of `part_id`. When retrieving the edges belonging to an edge group, the membership array will be filled with point numbers that comprise the edges of the edge group. Each edge is specified by two points, which means that the size of the array should be the size given by HAPI_GetEdgeCountOfEdgeGroup() * 2.
[in]	start	Start offset into the membership array. Must be less than HAPI_PartInfo_GetElementCountByGroupType() when it is a point or primitive group. When getting the membership information for an edge group, this argument must be less than the size returned by HAPI_GetEdgeCountOfEdgeGroup() * 2 - 1.
[in]	length	Should be less than or equal to the size of `membership_array`.

HAPI_DECL HAPI_GetGroupMembershipOnPackedInstancePart	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		HAPI_GroupType	group_type,
		const char *	group_name,
		HAPI_Bool *	membership_array_all_equal,
		int *	membership_array,
		int	start,
		int	length
	)

Get group membership for a packed instance part This functions allows you to get the group membership for a specific packed primitive part.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	part_id	The part id. (should be a packed primitive)
[in]	group_type	The group type.
[in]	group_name	The group name.
[out]	membership_array_all_equal	(optional) Quick way to determine if all items are in the given group or all items our not in the group. You can just pass NULL here if not interested.
[out]	membership_array	Array of ints that represent the membership of this group. Should be the size given by HAPI_PartInfo_GetElementCountByGroupType() with `group_type` and the HAPI_PartInfo of `part_id`.
[in]	start	Start offset into the membership array. Must be less than HAPI_PartInfo_GetElementCountByGroupType().
[in]	length	Should be less than or equal to the size of `membership_array`.

HAPI_DECL HAPI_GetGroupNames	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_GroupType	group_type,
		HAPI_StringHandle *	group_names_array,
		int	group_count
	)

Get group names for an entire geo. Please note that this function is NOT per-part, but it is per-geo. The companion function HAPI_GetGroupMembership() IS per-part. Also keep in mind that the name string handles are only valid until the next time this function is called.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	group_type	The group type.
[out]	group_names_array	The array of names to be filled. Should be the size given by HAPI_GeoInfo_GetGroupCountByType() with `group_type` and the HAPI_GeoInfo of `geo_id`.

Note: These string handles are only valid until the next call to HAPI_GetGroupNames().

Parameters

[in] group_count Sanity check. Should be less than or equal to the size of group_names.

HAPI_DECL HAPI_GetGroupNamesOnPackedInstancePart	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		HAPI_GroupType	group_type,
		HAPI_StringHandle *	group_names_array,
		int	group_count
	)

Get the group names for a packed instance part This functions allows you to get the group name for a specific packed primitive part. Keep in mind that the name string handles are only valid until the next time this function is called.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	part_id	The part id. (should be a packed primitive)
[in]	group_type	The group type.
[out]	group_names_array	The array of names to be filled. Should be the size given by HAPI_GetGroupCountOnPackedInstancePart() with `group_type` and the HAPI_PartInfo of `part_id`.

Note: These string handles are only valid until the next call to HAPI_GetGroupNamesOnPackedInstancePart().

Parameters

[in] group_count Sanity check. Should be less than or equal to the size of group_names.

HAPI_DECL HAPI_GetInstancedPartIds	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		HAPI_PartId *	instanced_parts_array,
		int	start,
		int	length
	)

Get the part ids that this instancer part is instancing.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	part_id	The instancer part id.
[out]	instanced_parts_array	Array of HAPI_PartId's to instance.
[in]	start	Should be less than `part_id's` HAPI_PartInfo::instancedPartCount but more than or equal to 0.
[in]	length	Should be less than `part_id's` HAPI_PartInfo::instancedPartCount - `start`.

HAPI_DECL HAPI_GetInstancerPartTransforms	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		HAPI_RSTOrder	rst_order,
		HAPI_Transform *	transforms_array,
		int	start,
		int	length
	)

Get the instancer part's list of transforms on which to instance the instanced parts you got from HAPI_GetInstancedPartIds().

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	part_id	The instancer part id.
[in]	rst_order	The order of application of translation, rotation and scale.
[out]	transforms_array	Array of HAPI_PartId's to instance.
[in]	start	Should be less than `part_id's` HAPI_PartInfo::instanceCount but more than or equal to 0.
[in]	length	Should be less than `part_id's` HAPI_PartInfo::instanceCount - `start`.

HAPI_DECL HAPI_GetOutputGeoCount	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		int *	count
	)

A helper method that gets the number of main geometry outputs inside an Object node or SOP node. If the node is an Object node, this method will return the cumulative number of geometry outputs for all geometry nodes that it contains. When searching for output geometry, this method will only consider subnetworks that have their display flag enabled.

This method must be called before HAPI_GetOutputGeoInfos() is called.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id of the Object or SOP node to get the geometry output count of.
[out]	count	The number of geometry (SOP) outputs.

HAPI_DECL HAPI_GetOutputGeoInfos	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_GeoInfo *	geo_infos_array,
		int	count
	)

Gets the geometry info structs (HAPI_GeoInfo) for a node's main geometry outputs. This method can only be called after HAPI_GetOutputGeoCount() has been called with the same node id.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id of the Object or SOP node to get the output geometry info structs (HAPI_GeoInfo) for.
[out]	geo_infos_array	Output array where the output geometry info structs will be stored. The size of the array must match the count argument returned by the HAPI_GetOutputGeoCount() method.
[in]	count	Sanity check count. The count must be equal to the count returned by the HAPI_GetOutputGeoCount() method.

HAPI_DECL HAPI_GetPartInfo	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		HAPI_PartInfo *	part_info
	)

Get a particular part info struct.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The SOP node id.
[in]	part_id	The part id.
[out]	part_info	HAPI_PartInfo return value.

HAPI_DECL HAPI_GetVertexList	(	const HAPI_Session *	session,
		HAPI_NodeId	node_id,
		HAPI_PartId	part_id,
		int *	vertex_list_array,
		int	start,
		int	length
	)

Get array containing the vertex-point associations where the ith element in the array is the point index the ith vertex associates with.

Parameters

[in]	session	The session of Houdini you are interacting with. See HAPI_Sessions for more on sessions. Pass NULL to just use the default in-process session.
[in]	node_id	The node id.
[in]	part_id	The part id.
[out]	vertex_list_array	An integer array at least the size of length.
[in]	start	First index of range. Must be at least 0 and at most HAPI_PartInfo::vertexCount - 1.
[in]	length	Must be at least 0 and at most HAPI_PartInfo::vertexCount - `start`.