Synopsis
PDX_MSGT gcr_ParabolicConic(long option, MDA_PTR orig_db_ptr, MTH_2DPNT xy_trans, double z_depth, double focal_dist, double t0, double t1, GDX_MATRIX gdx_matrix, int gdx_model, MDA_PTR *gdx_conic_ptr)
Purpose
Create a GDX Conic (parabola).
Description
This function given a 2D xy translation point, a z depth, focal length, a parametric start value (t0), and a parametric end value (t1) creates a parabolic GDX Conic entity.
The orig_db_ptr argument should contain the database pointer of the entity that the new entity was created from (usually this should be obtained by the calling routine via mda_GetOrigDbptr) or MDA_NULL_PTR. See the mda_intro man page for more information about predecessor entities.
\fBRules\fR .IP • 3 t0 is such that the focal_dist * t0 * t0 equals x start point and 2.0 * focal_dist * t0 equals y start point. .IP • 3 t1 is such that the focal_dist * t1 * t1 equals x end point and 2.0 * focal_dist * t1 equals y end point. .IP • 3 t0 != t1. .LP
Input
option
GCR_NOVALIDATE
No validation will occur on the input data.
orig_db_ptr
The original entities orig_db_ptr as obtained from the mda_GetOrigDbptr call, or MDA_NULL_PTR
xy_trans
The 2D XY translation, or NULL
z_depth
The depth of the parabola along the Z axis
focal_dist
The focal_dist.
t0
Start parametric value.
t1
End parametric value.
gdx_matrix
GDX rotation matrix, or NULL.
gdx_model
The GDX model for entity creation
Output
gdx_conic_ptr
Entity database pointer of the GDX Conic (parabola)
Tolerances
GDX ZERO_TOL
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Return
GCR_NOERR
GCR_INVALID_MODEL
GCR_PARA_T1
Low level error return
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