Import alignment from csv (#6234)

* Start of the official alignment API

* Import alignment into bonsai model using CSV file

src/bonsai/docs/guides/alignment.rst

@@ -0,0 +1,37 @@
+Road and Rail Alignments
+========================
+
+.. Note::
+
+    Bonsai lacks modeling features for road and rail alignments. This feature is intended to be a stop-gap measure to allow alignments
+    to be defined and imported into an IFC model. This feature is most likely temporary and will be phased out as robust alignment
+    modeling capabilities are developed.
+
+Alignments may be defined by the PI method in a CSV file for import into an IFC4X3 Bonsai project. The format of the CSV file is as follows:
+
+.. csv-table:: Alignment by PI Method
+
+   "X1","Y1","R1","X2","Y2","R2","...,","Xn-1","Yn-1","Rn-1","Xn","Yn","Rn"
+   "D1","Z1","L1","D2","Z2","L2","...,","Dn-1","Zn-1","Ln-1","Dn","Zn","Ln"
+   "D1","Z1","L1","D2","Z2","L2","...,","Dn-1","Zn-1","Ln-1","Dn","Zn","Ln"
+   
+   
+where:
+   Xi,Yi are horizontal alignment PI points
+   Ri are horizontal curve radii.
+   Di,Zi are vertical alignment PI points as Distance_Along,Elevation
+   Li are the horizontal length of parabolic vertical transition curves
+   
+R1 and Rn, as well as L1 and Ln, are placeholder values and should be set to 0.0
+
+The CSV file must contain exactly one horizontal alignment definition with a minimum of three points.
+X1,Y1 is the Point of Beginning (POB). Xn,Yn is the Point of Ending (POE).
+
+The CSV file may contain zero, one or more vertical alignment definitions.
+
+Alignments with a single horizontal layout and zero or one vertical layout are modeled per `IFC Concept Template 4.1.4.4.1.1, Alignment Layout - Horizontal, Vertical, and Cant, <https://ifc43-docs.standards.buildingsmart.org/IFC/RELEASE/IFC4x3/HTML/concepts/Object_Composition/Nesting/Alignment_Layouts/Alignment_Layout_-_Horizontal,_Vertical_and_Cant/content.html>`_. Alignments with multiple vertical layouts are modeled per `IFC Concept Template 4.1.4.4.1.2, Alignment Layout - Reusing Horizontal Layout, <https://ifc43-docs.standards.buildingsmart.org/IFC/RELEASE/IFC4x3/HTML/concepts/Object_Composition/Nesting/Alignment_Layouts/Alignment_Layout_-_Reusing_Horizontal_Layout/content.html>`_.
+
+Example based on the `FHWA Bridge Geometry Manual <https://www.fhwa.dot.gov/bridge/pubs/hif22034.pdf>`_:
+
+500,2500,0.0,3340,660,1000,4340,5000,1250,7600,4560,950,8480,2010,0
+0,100,0,2000,135,1600,5000,105,1200,7400,153,2000,9800,105,800,12800,90,0

src/bonsai/docs/index.rst

@@ -56,6 +56,7 @@ and data-rich OpenBIM with Blender :)
       guides/authoring/georeferencing
       guides/authoring/git_support
       guides/development/index
+      guides/alignment
       guides/authoring/other_addons
       guides/troubleshooting
       guides/debugging

src/bonsai/docs/reference/topbar.rst

@@ -98,3 +98,4 @@ Imports data from external sources into the Blender session or IFC model.
 - **P6 (.xer)**: Imports a P6 XER file containing a work schedule into the active IFC model.
 - **Powerproject (.pp)**: Imports a Powerproject file containing a work schedule into the active IFC model.
 - **Microsoft Project (.xml)**: Imports a Microsoft Project XML file containing a work schedule into the active IFC model.
+- **Alignment (.csv)**: Imports a CSV containing horizontal and vertical alignments defined by the PI method into the active IFC model.