MicroStation PowerDraft CONNECT Edition Help

Reprojection Settings Dialog

Used to specify the settings for reprojection. The tabs let you set reprojection settings differently for references and for the active model.

You can access this dialog from the following:
  • Geographic Coordinate System dialog: select the Edit Reprojection Settings icon


SettingDescription
Stroke Tolerance Specifies the maximum allowable separation between the chord representing a line string approximation of a curved element and the exact curve. The units are master units of the active model. The smaller the number, the finer the approximation and the slower the algorithm. Stroke Tolerance is used for all stroke options.
Reproject Cell components individually Determines if cell components should be reprojected individually. Always reprojects every element in every cell. Never treats all elements as single entities. The default, If Spatially Large, reprojects every component of cells that occupies more than an area of .2 square kilometers in the X-Y plane, and treats smaller cells as single entities.

Reprojecting each component element individually is best for cells representing a man made unit, such as a transformer box or parking lot light. Calculating the best linear transform at the cell origin and then applying transform to all components, treating the cell as a single entity, is best for geographic features that have been grouped as a cell for convenience.

Reproject Multiline Text components individually Determines if multiline text components (text nodes) should be reprojected individually. Always reprojects every text element in multiline text. Never treats all text elements as single entities. The default, If Spatially Large, reprojects every text component of multiline text that occupies more than an area of .2 square kilometers in the X-Y plane, and treats smaller cells as single entities.
Rotate Cells Rotates cells by the geographic coordinate system convergence angle calculated at the cell origin. Yes is the default setting.
Scale Cells Scales cells by the geographic coordinate system scale factor calculated at the cell origin. Yes is the default setting.
Rotate Text Elements Rotates text elements by the geographic coordinate system convergence angle calculated at the cell origin. Yes is the default setting.
Scale Text Elements Scales text elements by the geographic coordinate system scale factor calculated at the cell origin. Yes is the default setting.
Stroke Arcs to Line Strings Strokes an arc to a line string approximation (the accuracy of the approximation depends on the Stroke Tolerance setting) and then reprojects points in the line string; the arc loses its identity as an arc. In many reprojections, the path of an arc does not remain an arc. This setting can be set to Always, Never, and, the default, If Spatially Large.

If an arc is not stroked, the best fit reprojected arc is calculated.

Stroke Ellipses to Line Strings Strokes an ellipse to a line string approximation (the accuracy of the approximation depends on the Stroke Tolerance setting) and then reprojects points in the line string; the ellipse loses its identity as an ellipse. In many reprojections, the path of an ellipse does not remain an ellipse. This setting can be set to Always, Never, and, the default, If Spatially Large.

If an ellipse is not stroked, the best fit reprojected ellipse is calculated.

Stroke Curves to Line Strings Strokes an Akima curve element (element type11) to a line string approximation (the accuracy of the approximation depends on the Stroke Tolerance setting) and then reprojects points in the line string; the Akima curve element loses its identity as an Akima curve element. In many reprojections, the path of an Akima curve element does not remain an Akima curve element. This setting can be set to Always, Never, and, the default, If Spatially Large.

If an Akima curve element is not stroked, the best fit reprojected Akima curve element is calculated.

Reproject Elevations If on, and the coordinate system is 3D, MicroStation PowerDraft corrects the Z values of coordinates when the datum or geoid elevation of the source and destination Geographic Coordinate Systems are different. If off, the Z values are unchanged. The default is to leave Z values unchanged.
Add Points If Needed Inserts points along a line so that it stays along the correct path within the Stroke Tolerance setting. This improves quality but requires more processor time and controls situations where a line segment appears straight in one projection but appears curved in another. For example, lines of constant latitude in an Equidistant Cylindrical projection are straight horizontal lines, but in a Lambert Conformal Conic projection they are arcs of varying radius. If a particular boundary drawn exactly along a parallel is represented by a long line in a design using an Equidistance Cylindrical projection, the end points are reprojected but it still appears as a straight line when reprojected to a Lambert Conformal Conic projection.