BLEFXF ( l_wall, r_wall, l_rev, r_rev, ntokens, tokens, bdata, status, s_data,
===============================================================================
sheets, nblend, blends, unders, ifail )
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Create a blend between the specified faces.
Receives:
KI_tag_list_face *l_wall --- list of faces in left wall
KI_tag_list_face *r_wall --- list of faces in right wall
KI_cod_logical *l_rev --- blend direction from left wall
KI_cod_logical *r_rev --- blend direction from right wall
<KI_int_nitems> *ntokens --- number of blending tokens
KI_cod_fxft tokens[ntokens] --- blending tokens
<KI_tag_list> bdata[ntokens] --- data associated with tokens
Returns:
KI_cod_fxfe *status --- blend success status flag
<KI_tag_list_entity> *s_data --- data associated with status flag
<KI_tag_list_body> *sheets --- the blend sheets created
<KI_int_nitems> *nblend --- number of blend faces created
<KI_tag_list_face> *blends --- the blend faces
<KI_tag_list_list> *unders --- list of lists of underlying data
KI_cod_error *ifail --- failure code
Specific errors:
KI_fxf_blend_failed could not create blends on body
KI_fxf_blend_bad_token Illegal face face blend token
KI_not_in_same_partition Faces are not all in the same partition
Description:
This function creates one or more blends between the two sets of faces
provided. The user specifies whether the blend will be attached to the
bodies involved or returned as a separate sheet body. For further details on
this function, see the Blending section of the Functional Description.
'l_wall' is a list of the faces which make up the 'left' wall. These faces
must all lie in the same shell of the same body.
'r_wall' is a list of the faces which make up the 'right' wall. These faces
must all lie in the same shell of the same body.
The two walls do not need to lie in the same body. If the blend does not
contact either the first face in 'l_wall' or the first face in 'r_wall'
(or both), then BLEFXF will fail.
'l_rev' is a logical determining which side of 'l_wall' the blend lies. The
blend lies in the direction of the face normals if 'l_rev' is false.
'r_rev' is a logical determining which side of 'r_wall' the blend lies. The
blend lies in the direction of the face normals if 'r_rev' is false.
'tokens' consists of 'ntokens' face face blend properties, and 'bdata' is a
parallel array of 'ntokens' tags of data lists for these properties, some
of which may be null tags. The meanings of the various tokens are given
below.
Trimming Tokens.
The user may give more than one trimming token to specify attachment
and trim options.
FXFTAT Trim blend and walls and attach blend.
The associated value in 'bdata' is the null tag.
The blend end boundaries will be determined by the wall boundaries
unless further trim options are specified.
The walls will be trimmed by the blend boundaries.
The blend will be attached to the walls. If the walls lie in
different bodies the bodies will be combined, with the body
containing the 'left' wall being considered as the target body. If
'l_rev' and 'r_rev' are not the same, the body containing the right
wall will be negated in order to produce a consistent result.
This is the default trimming option.
FXFTTW Trim blend and walls.
The associated value in 'bdata' is the null tag.
The blend end boundaries will be determined by the wall boundaries.
The walls will be trimmed by the blend boundaries.
This token is only valid if the blend is being formed between two
sheet bodies.
The blend will not be attached to the walls but will be created as a
separate sheet body.
FXFTTB Trim blend to walls.
The associated value in 'bdata' is the null tag.
The blend end boundaries will be determined by the wall boundaries.
Unless walls are set to attach, FXFTAT, then walls will not
be trimmed, and the blend will not be attached to the walls but
will be created as a separate sheet body.
FXFTST Short trim to walls.
The associated value in 'bdata' is the null tag.
The blend end boundaries will be the constant parameter lines
determined by the wall boundaries such that the blend is as short
as possible.
Unless walls are set to attach, FXFTAT, then walls will not
be trimmed, and the blend will not be attached to the walls but
will be created as a separate sheet body.
FXFTLT Long trim to walls.
The associated value in 'bdata' is the null tag.
The blend end boundaries will be the constant parameter lines
determined by the wall boundaries such that the blend is as long
as possible.
Unless walls are set to attach, FXFTAT, then walls will not
be trimmed, and the blend will not be attached to the
walls but will be created as a separate sheet body.
FXFTNT Do not trim blend.
The associated value in 'bdata' is the null tag.
The blend will not be trimmed to the wall extent. Its end boundaries
will be constant parameter lines.
Unless walls are set to attach, FXFTAT, then walls will not
be trimmed, and the blend will not be attached to the
walls but will be created as a separate sheet body.
Blend Definition Tokens.
The user may give any number of blend definition tokens, though some are
mutually exclusive. The user must provide one of FXFTCB, FXFTVB, FXFTDB,
FXFTHL or FXFTCL. The table below gives the rules for combining tokens.
Each column shows which of the other tokens:
'M' must be given,
'O' can be given,
'X' must not be given
if the token at the head of the column is given.
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FXFTCB FXFTVB FXFTHL FXFTCE FXFTTL FXFTRC FXFTCL FXFTCC FXFTDB
===========================================================================
FXFTCB - X O O O X O X X
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FXFTVB X - O O O M O X X
---------------------------------------------------------------------------
FXFTHL O O - O O X O X X
---------------------------------------------------------------------------
FXFTCE O O O - O O O X O
---------------------------------------------------------------------------
FXFTTL O M M O - M M M M
---------------------------------------------------------------------------
FXFTRC X O X O O - X X X
---------------------------------------------------------------------------
FXFTCL O O O O O X - M X
---------------------------------------------------------------------------
FXFTCC X X X X O X O - X
---------------------------------------------------------------------------
FXFTDB X X X O O X X X _
---------------------------------------------------------------------------
FXFTCB Constant radius rolling ball blend.
The associated value in 'bdata' is a list containing a positive double.
The blend will be a constant radius rolling ball blend, whose radius
is the given double.
FXFTVB Variable radius rolling ball blend.
The associated value in 'bdata' is a list containing two curve tags.
The blend will be a variable radius blend. The first curve provided
will be used as a parameter curve and the second as a law curve.
The law curve is a B-curve whose parameter space is that of a portion
of the parameter curve in the region of the blend. The law should be
three dimensional though it does not represent 3-space points. The
meaning of the coordinates are:
x-coordinate = range of blend off left wall.
y-coordinate = range of blend off right wall.
z-coordinate = rho value.
The ranges must be positive, except at the ends of the blend where
they are allowed to be zero. The left and right ranges need not be
equal unless: i) either range is zero, at which point both ranges must
be zero, or ii) the token FXFTHL is also given.
By default, the blend will have circular cross-section if the ranges
are equal, and elliptical cross-section otherwise. The rho values of
the law curve can be used to control the cross-sectional shape of
the blend by providing the token FXFTRC (see below).
FXFTHL Blend is constrained by tangent hold lines.
The associated value in 'bdata' is a list of edge tags.
The blend will be constrained to be a tangent hold line blend in the
region of the given edges. If this token is provided with FXFTCB
or FXFTVB the blend need not be constrained by these edges. If this
token is given with FXFTVB, the left and right ranges of the law
curve must be equal.
FXFTCL Blend is constrained by conic hold lines.
The associated value in 'bdata' is a list of edge tags.
The blend will be constrained to be a conic hold line blend in the
region of the given edges. If this token is provided with FXFTCB
or FXFTVB the blend need not be constrained by these edges. If this
token is given with FXFTCC or without FXFTCB or FXFTVB, then FXFTHL
and FXFTCE must not be provided, and the number of edge tags
in bdata must be at least two.
FXFTCC Curvature Continuous blend.
The associated value in 'bdata' is a list containing two curve tags.
This token must be provided with the token FXFTCL and the blend
will be constrained to be curvature continuous at the hold lines.
The first curve provided in 'bdata' will be used as a parameter curve
and the second as a depth control curve.
The depth curve is a B-curve whose parameter space is that of a portion
of the parameter curve in the region of the blend. The depth
curve should be three dimensional though it does not represent
3-space points. The meaning of the coordinates are:
x-coordinate = A value strictly between 0 and 1 giving the position
of the maximum depth of the blend between the blend
walls. A value close to 0 will force the cross section
to have maximum depth close to the left wall, whilst a
value close to 1 will force the cross section
to have maximum depth close to the right wall.
y-coordinate = A value strictly between 0 and 1 giving the maximum
depth of the blend. A value close to 0 will force the
maximum depth of the blend to be as shallow
as possible, whilst a value close to 1 will force the
blend to be as deep as possible.
z-coordinate = ignored.
FXFTCE Blend is constrained by cliff edges.
The associated value in 'bdata' is a list of edge tags.
The blend will be constrained to be cliffedge blend in the
region of the given edges.
FXFTTL A tolerance is associated with this blend.
The associated value in 'bdata' is a list containing the tolerance.
FXFTRC Variable radius blend cross-section is controlled by rho values
from the law curve.
The associated value in 'bdata' is the null tag.
The rho values must lie in the range 0 < rho < 1. The blend
cross-section will be:
1) an ellipse for 0 < rho < 0.5
2) a parabola for rho == 0.5
3) a hyperbola for 0.5 < rho < 1.
FXFTDB Variable radius disc blend.
The associated value in 'bdata' is a list containing two curve tags.
The first curve provided will be used as a parameter curve and the
second as a law curve.
The blend will be a variable radius disc blend. The generating
disc lies in the normal plane of the parameter curve; its size is
defined by the law curve.
For description of the law curve, see the documentation of FXFTVB
above. Note that the rho value is ignored, since this token is
incompatible with FXFTRC.
This token may not be provided with FXFTPR.
Control Tokens.
The user may supply any combination of control tokens
FXFTHP Help point provided.
The associated value in bdata is a list of three doubles.
The three doubles will be used as coordinates of a help point, which
will be used to differentiate between multiple alternative possible
blends between the walls. If there is a blend which passes
close to the help point, it will be the one created.
FXFTMS Create multiple blends sheets.
The associated value in bdata is the null tag.
BLEFXF will only create one blend unless this token is provided, in
which case it will create all blends which lie in at least one of the
master faces.
FXFTPR Propagate blends.
The associated value in bdata is the null tag.
If this token is given the blends will be allowed to propagate past
smooth edges beyond the provided walls.
FXFTLP Limit Plane.
The associated value in bdata is a list containing one or two tags.
The tags must be the tags of planes.
The blend will be trimmed to end in a constant parameter line
determined by a plane. The blend will lie on the positive side of
the plane.
This token is only valid if one of the trimming tokens FXFTNT,
FXFTTB, FXFTST or FXFTLT is also provided.
FXFTEO End Overflow
The associated value in bdata is the null tag.
If this token is given the blend will be allowed to extend past
notches, whether in the middle or at the end of the blend.
FXFTSO Create solid body if possible
The associated value in bdata is the null tag.
If this token is supplied and the result of the blending operation
encloses a volume then a solid body will be created. Otherwise a sheet
body will be returned.
This token is only valid if the blend is being attached, i.e. the
trimming token FXFTAT is used.
'status' is a success status flag for BLEFXF, for those cases where an ifail
is not returned. 's_data' consists of supporting data.
The possible returns are
FXFEOK The requested blend succeeded.
The associated value in 's_data' is the null tag.
FXFEST The blend has not been attached, nor have the walls been trimmed
but blend sheet bodies have been created. This token is only returned
if BLEFXF was called with FXFTAT or FXFTTW and represents a
partial success.
The associated value in 's_data' is the tag of a list. This list
contains the tag of a list of three doubles and the tag of some
topology. These indicate the region where the blend could not be
attached.
FXFEER The blend could not be created.
The associated value in 's_data' is the null tag.
FXFEID The user has supplied insufficient data to define a blend.
The associated value in 's_data' is the null tag.
FXFEXD The user has supplied inconsistent data.
The associated value in 's_data' is the null tag.
FXFEIF The user has supplied an invalid wall of faces.
The associated value in 's_data' is the invalid list of faces.
FXFEIR The user has supplied an invalid range definition.
The associated value in 's_data' is the null tag.
FXFEIH The user has supplied invalid tangent hold line data.
The associated value in 's_data' is the invalid tangent hold line
data.
FXFEIC The user has supplied invalid cliff edge data.
The associated value in 's_data' is the invalid cliff edge
data.
FXFEFC A face in a wall is too tightly curved for the blend to fit.
The associated value in 's_data' is the face in question.
FXFERS A blend range is too small.
The associated value in 's_data' is a list containing one double.
This is the suggested larger range for the blend.
FXFERL A blend range is too large.
The associated value in 's_data' is a list containing one double.
This is the suggested smaller range for the blend.
FXFELN 'l_rev' is incorrect.
The associated value in 's_data' is the null tag.
FXFERN 'r_rev' is incorrect.
The associated value in 's_data' is the null tag.
FXFEBN Both 'l_rev' and 'r_rev' are incorrect.
The associated value in 's_data' is the null tag.
FXFESC The blend sheet(s) intersect one another and hence could not be
attached.
The associated value in 's_data' is the tag of a list. This list
contains the tag of a list of three doubles and the tags of some
topology. These indicate which sheet(s) clashed and the point
at which they clashed.
FXFEWC The blend, which has been attached, has combined two bodies and has
produced a face-face inconsistency elsewhere in the model.
The associated value in 's_data' is a list containing the tags of
a pair of clashing faces.
FXFEFF The blend,which has been attached, has caused a face-face
inconsistency.
The associated value in 's_data' is a list containing the tags of
a pair of clashing faces.
FXFEGX The blend contains face(s) with self intersecting geometry.
The associated value in 's_data' is a list containing the tags of
the blend faces with self-intersecting surfaces.
FXFERV The user has supplied invalid rho values in the law curve.
The associated value in 's_data' is the null tag.
FXFEAR The user has supplied asymmetric ranges which are inconsistant with
the underlying geometry.
The associated value in 's_data' is the null tag.
FXFECL The user has supplied invalid conic hold line data.
The associated value in 's_data' is the invalid conic hold line
data.
FXFEIS The user has supplied an invalid parameter spine.
The associated value in 's_data' is a list containing the tag of
the invalid spine and possibly a list of three doubles, representing
a point where the spine is unsuitable.
If BLEFXF has successfully created a blend, then 'sheets' will consist of a
list of all new blend sheet bodies created, or null if the blend has been
attached. 'blends' will consist of a list of the 'nblend' blend faces.
'unders' will consist of a parallel list of 'nblend' lists of integers. These
lists contain the ( possibly dead ) tags of the underlying topology used to
determine the equivalent blend face in 'blends'. Each list will consist of the
tag of the face in the left wall, then the tag of the face in the right wall,
then any other data that determined the geometry of the blend face, such as a
cliff edge or tangent hold line.
