Create Best Fit Alignment Dialog Box

Use this dialog box to specify the settings to use when creating an alignment by best fit through a series of objects.

Input Data

Input Type

Specifies the type of source objects (AutoCAD Blocks, AutoCAD Entities, AutoCAD Points, COGO Points, or Feature Lines) from which to create the best fit alignment.

Weeding Options

Opens the Weeding Options dialog box, which enables you to specify options for adding or removing vertices when using either feature lines or AutoCAD entities as the input data.

Path 1

Specifies that the alignment is created through a single path of regression points.

Use this option to create an alignment from centerline sample data.

Path 2

Specifies that the alignment is created between two paths of regression points.

Use this option to create a centerline alignment between sample data of the either the edges of pavement of a road, or the left and right rails.

Best Fit Options

These options affect the manner in which the best fit algorithm is applied to the input data.

Maximum Radius For Curve Detection

Specifies the largest acceptable radius of curves that are created from the input data.

Note: This value is an estimate. For best results, specify a value that is slightly greater than the largest known radius in the input data.
Create Spirals

Specifies that spirals are created between the alignment tangents and curves. The spirals on either side of a curve are symmetric unless the match tangents option is selected.

Note: When this option is selected, the options below it become available.
Desired R/A For Spirals

Specifies the target R/A ratio for spirals that are created.

Create Spirals And Match Tangents Where Possible

Specifies that the solution will follow the tangents as much as possible. If no solution is available, then the tangents are moved toward the circles until a spiral solution is found between the tangent and the curve.

Minimum R/A For Spirals

Specifies the minimum R/A ratio for spirals that are created. This value controls the length of the spirals:

  • A higher value produces shorter spirals.
  • A lower value produces longer spirals.

Creation Settings

Alignment Name

Specifies the name of the alignment. Each alignment must have a unique name.

Site

Specifies a site for the alignment. Select a site from the Site list, or enter a new site name.

Note: The default selection is <None>, which places the alignment in the top-level Alignments collection in Prospector. See About Alignment and Site Interaction for more information.
Alignment Style

Displays the current style. Click the arrow to select another alignment style.

Alignment Label Set

Displays the default alignment label set. Click the arrow to select another alignment label set.

Layer

Displays the layer on which the alignment object is created. Click the arrow to select another layer.

Spiral Type

Specifies the spiral type to use in the best fit alignment. For more information, see About Spiral Definitions.

Note: The Sine Half-Wave Diminishing Tangent and NSW Cubic Parabola are not supported for best fit alignments.
Show Report

Opens the Best Fit Alignment Report vista, which lists the results of the best fit regression, including the coordinates of each regression point.

Label Offsets

Creates labels in the drawing that show the Offset to Entity information that is displayed in the Best Fit Alignment Report vista.

The labels show the positive or negative horizontal offset distance from the best fit alignment to the input data (entities). A positive value indicates that the input data is on the right of the best fit alignment (when starting at station 0+00), and a negative value indicates that the input data is on the left of the best fit alignment.

Note: These labels use the Standard text style at a height of 1.00, and they are created on layer 0.