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2020-09-07 SQL Server Functions
- STHasCircularString.sql – Checks if supplied geometry contains a CircularString
- STLineToCurve – Alpha release of a function that converts a LineString into a CompoundCurve
- STNumCircularStrings.sql – Now counts CircularStrings throughout whole of a CurvePolygon, CompoundCurve, GeometryCollection not just a single CircularString parameter
2020-08-29 SQL Server Functions
Main changes related to refactoring CircularString mathematics and functions that call them.
- STCircularString2Circle.sql — Supplied with a circular string this function creates its polygon equivalent
- STCircularStringAngleAtCentre.sql — Supplied with a CircularString, this function computes the angle the arc makes at the centre of its circle.
- STCircularStringAngleToPoint.sql — Supplied with a circular string and a point, this function computes the (subtended) angle from the start of the arc to the supplied point.
- STCircularStringLengthToPoint.sql — Supplied with a circular string and a point, this function computes the distance from the start of the arc to the supplied point.
- STCircularStringN.sql — Handles CompoundCurve with a single 30-point CircularString
- STEquals.sql — Fixed handling of Z and M values in STEqualsByDistance
- STSegmentize.sql — Fixed calculation of start_length; Changed call to renamed STMakeCircularString
- STWhichSide.sql — Fixed handling of of CircularStrings with subtended angle of > 180.0
- STAddMeasure.sql — Improved documentation; changed handling of start/end measure parameters.
- STFilterLineSegment.sql — Delayed application of rounding of ordinates to point where geometry is returned.
- STFindPointByMeasure.sql — Changed to use STFilterLineSegment instead of STSegmentize; Improved ordinate comparison.
- STProjectPoint.sql — Changes to use STFilterLineSegment instead of STSegmentize; Improved ordinate comparison.
Replaced by new CircularString functions.
2020-07-31 SQL Server Functions
Performance improvements were made to the LRS functions at the request of a donator.
This meant a change to STWhichSide, STProjectPoint and a replacement STFilterLineSegment.
- STFilterLineSegment — Ported from previous version for use in performance improvements.
- STNumCircularStrings — Returns number of CircularString elements in provided CircularString.
- STProjectPoint — Changed to use STFilterLineSegment. Fixed wrong calculation of ratios.
- STFindOffset — Fixed wrong use of calculation point for offset.
- STWhichSide — Implemented short circuit of segmentizing when not needed.
2020-07-09 PostGIS Functions
A new install scripts has been created and added.
New functions have been added with others undergoing rationalisation.
2020-06-20 SQL Server Functions
- STReflect — A function which reflects the supplied geometry about the supplied 2 point reflection line.
- STOffsetSegment — Fixed offset side bug for CircularStrings with subtended angles less than greater than 180 degrees.
- Function deletion by install script only drops functions and procedures in the package.
2020-06-11 SQL Server Functions
Many functions not mentioned here have had improvements in documentation.
A lot of reorganisation of development folders, deployment scripts and checking, along with a move to github, has occurred since the last release.
- STAsEWKT() – Implements an method to create Extended Well Known Text (EWKT) strings from the input geometry.
- STComputeArcLengthToPoint() – Supplied with a circular string and a point, this function computes the distance from the start of the arc to the supplied point.
- STFindCircularStringAngle() – Supplied with a cicular arc, this function computes the angle the arc makes at the centre of its circle.
- STPopulateGeometryColumns() – Detect tables with geometry datatype columns and adds them to [$(owner)].[geometry_columns]
- STAddGeometryColumn() – Adds/Updates a single table with geometry datatype columns to [$(owner)].[geometry_columns]
- STCollectionAppend() – Appends geometry to end of the geometry collection.
- STCollectionDeduplicate() – Determines all possible spatial relations between two geometry instances.
- STCollectionExtract() – Extracts geometry of specified geometey type from the geometry collection.
- STSimilarityByArea() – Function that compares two polygons where their ordinates are not perfectly equal.
- STThinnessRatio() – Computes a measure of the thinness of a polygon (cf area/perimiter ratio)
- STSmoothTile() – Smooths polygon created from raster to segment conversion.
- STIntersect2CircularArcs() – Finds intersections between one CircularString another.
- STIntersectCircularArc() – Computes intersection between a linestring and a CircularString.
- STSnapPointToGeom() – Function that snaps a point to a geometry returning (uses ShortestLineTo).
- STDetermine() – Added support for Area Similarity Ratio
- STCogoFunctions() – Various.
- STIsGeo() – Improved geometry/geography identification.
- STMakeLineFromCollection() – Added STIsValid to various functions’ parameter checking
- STMakePoint() – Bug fix.
- STOffsetLine() – Added STIsValid to parameter checking
- STOffsetPoint() – Fixed Measure issue, changed COALESCE to ISNULL. Fixed function declaration problem.
- STOffsetSegment() – Added STIsValid test. Implemented missing CircularString processing.
- STRemoveOffsetSegments() – Added documentation. Improved parameter testing. Improved STMakeLineFromGeometry SQL processing.
- STReduce() – Fixed bug with reduction ratio.
- STVertices() – Re-wrote as in-line function that uses STSegmentize()
- STProjectPoint() – Improved documentation. Fixed bug with handling CircularString Measure calculation.
- STFindOffset() – Improved documentation. Fixed adding of offset positive/negative directions.
- STFindPointByMeasure() – Improved Documentation.
- STFindPointsByMeasures() – Renamed from STFindPointsByDeltaMeasure().
- STPostGIS() – Added @p_radius_check to a number of functions that call functions that now have @p_radius_check capability.
- STSplitProcedure() – Improved Documentation, plus added @p_radius_check.
- STSplit() – Improved Documentation, plus added @p_radius_check.
2020-12-02 SQL Server Functions
- STAsEWKT.sql – Convert geometry to EWKT
- STGeomFromEWKT.sql – Convert EWKT to geometry
- STBearingAlongLine.sql – Wrapper over STBearing
- STTo2D.sql – Function that removes any ZM ordinates to return a geometry with XY ordinates only.
- STWhichSide.sql (moved from LRS to General)
- STFindPointsByDeltaMeasure.sql – An LRS function that allows one to generate all measures along a line and a set of offsets at each measure point.
- STAppend.sql – Substantion changes to better support CircularStrings and CompoundCurves
- STFindPointBisector.sql – Improved function after extensive testing.
- STOffsetLine.sql – Improved function after extensive testing.
- STOffsetPoint.sql – Improved function after extensive testing.
- STOneSidedBuffer.sql – Improved function after extensive testing.
- STRemoveOffsetSegments.sql – Used by STOneSidedBuffer.
- STRemoveSpikes.sql – Formatting
- STVertices.sql – Formatting
- STFindPointByLength.sql – Support for disappearing offsets in circularStrings.
- STFindPointByMeasure.sql – Support for disappearing offsets in circularStrings.
- STFindSegmentByLengthRange.sql – Migrated to STSegmentize and support for radius check chagnes.
- STFindSegmentByMeasureRange.sql – Migrated to STSegmentize and support for radius check changes.
- STIsMeasured.sql – Modified documentation.
- STPostGIS.sql – Modified wrapper functions for support of radius check and other changes.
- STReverseMeasure.sql – Corrected bug found in testing.
- STSplitSegmentByLength.sql – Migrated to STSegmentize and support for radius check changes.
- STSplitSegmentByMeasure.sql – Migrated to STSegmentize and support for radius check changes.
- STGetGeomMetadata.sql – Added GEOMETRY_COLUMNS table generation and function to populate it.
2019-12-18 SQL Server Functions
- STOffsetPoint.sql which offsets a single linestring or circularstring.
Integrated Linestring and Arc (CircularString) functions into the following modified functions:
Rationalisation of unneeded functions
- STReverseMeasure.sql – Modified to use STSegmentize
- STAddMeasure.sql – Modified to use STSegmentize
- STScaleMeasure.sql – Modified to use STSegmentize
- STAverageBearing.sql – to support CircularStrings and CompoundCurves
2019-12-17: SQL Server Functions
- STAverage.sql – A trivial function that averages the ordinates of two points.
- STComputeTangentPoint.sql – Extracted from STCogoFunctions.sql, and revamped
- STFindPointBisector.sql – Extracted from STCogoFunctions.sql and revamped
- STOffsetPoint.sql – Move code from other functions to execute, as a single function, the offsetting of a point from a 2-point linestring or 3-point circularstring.
- STFindDeflectionAngle.sql – Improved with support for CompoundCurves.
- STMakeLines.sql – Modified STMakeCircularLine to return LineString if three points are collinear
- STSegmentize.sql – A number of improvements such as more debugging of filters like MEASURE_RANGE
2019-11-27: PostGIS Functions
- ST_CircularStringN — Extracts nominated 3-point circular string from a CIRCULARSTRING with more than 3 points.
- ST_CurveN — Returns requested Curve within COMPOUNDCURVE
- ST_HasM — Determines if supplied geometry has M ordinates.
- ST_HasZ — Determines if supplied geometry has Z ordinates.
- ST_MakeCircularString — Makes a 3 point circular arc from 3 supplied points
- ST_NumCircularStrings — Compute number of 3-point circular strings within a CIRCULARSTRING with more than 3 points.
- ST_NumCurves — Returned number of sub-objects within a COMPOUNDCURVE
- ST_Segmentize — Version of ST_Vectorize that honours COMPOUNDCURVE and CIRCULARSTRING objects.
2019-11-04: SQL Server Spatial Functions.
- STAverageBearing — Function that computes average bearing of segments in linestring.
- STBoundingDiagonal — Returns the diagonal of the supplied geometry’s bounding box as a linestring.
- STCheckRadii — Checks if radius of any three points in a linestring are less than the desired amount.
- STDirectVincenty — Vincenty Direct Solution of Geodesics on the Ellipsoid.
- STEllipsoidParameters — Given a SRID returns the semi major axis and flattening from the sys.spatial_reference_systems table.
- STGeographicDistance — Computes distance in meters along parallel latitude/medidian longitude or direct.
- STInverseVincenty — Vincenty inverse calculation between two points
- STIsCollinear — Function that checks if a linestring’s points all lie on straight line.
- STRemoveOffsetSegments — Removes any start/end segment in provided linestring that disappear when segments are offset.
- STTileByNumGrids — Covers supplied geometry object with a mesh of a specific number of times in X and Y.
- STTileGeogByPoint — Creates mesh of tiles anchored to supplied point.
- STTileGeomByPoint — Creates mesh of tiles anchored to supplied point.
- STisCCW — A filter for computing the orientation index of three coordinates.
- STOffsetLine from STLineOffset
- STOffsetSegment from STParallelSegment
2019-10-18: SQL Server Spatial Functions.
- Added STForceCollection – Takes polygon and returns GEOMETRYCOLLECTION of rings as polygons or linestrings or MULTILINESTRING with rings as linestrings
- Added STMBRLongestSide – Computes Envelope or MBR of input geometry and then computes and returns the longest side of the Envelope or MBR
- Added STMBRShortestSide – Computes Envelope or MBR of input geometry and then computes and returns the shortest side of the Envelope or MBR
- Updated STAppend – Corrected missing case
- Updated STMakeLineFromGeometryCollection – Improved to allow GeometryCollection to hold LineStrings not just Points.
- Updated STParallel – Continue to improve parallel offsetting of linestrings.
- Updated STVertices – Modified return table to include actual geometry Point.
- Updated STDumpRings – Fixed issue with function not dumping interior rings.
- Updated STConvertToLineString – Fixed bug with single MultiLineString in Geometry Collection.
2019-08-17: Oracle JTS Utilities.
- Added ST_OffsetLine – Offsets a linestring by the required value with optional styling.
- Added ST_OneSidedBuffer – Creates a buffer polygon on one side of the supplied line with optional styling.
- Updated ST_Buffer to remove one sided option
2019-08-16: SQL Server Spatial.
- Added STPointToCircularArc which returns a measured point by snapping provided point to the provided circularstring
- Updated STProjectPoint to support CircularString and CompoundCurve objects via STPointToCircularArc.
- Updated documentation.
2019-07-19: SQL Server Spatial.
- Corrected installation errors
- Fixed STPointFromText null Z with M handling
- Moved all PostGIS LRS functions into a single script.
- Added STLocateBetweenElevations, STLineSubstring, and STLineInterpolatePoint
- Modified STExtract to extract polygon ring sub elements where ring defined using CircularCurve or CompoundCurve.
- Modified STIsMeasureDecreasing
- Modified STCogo2Line
- Improved function documentation.
- Updated html documentation.
2019-05-17: SQL Server Spatial
- Added STDensify function which implements a basic geometry densification algorithm.
- Added STGeometryTypes function which extracts all geometry type keywords from a geometry (and its sub-elements) eg COMPOUNDCURVE,LINESTRING,CIRCULARSTRING
2019-01-12: Oracle PLSQL Object code.
- Created install.sh Linux bash script