PolygonMapBuffer
PolygonMapConvexHull
PolygonMapIntersect
PolygonMapDifference
PolygonMapSymetricDifference
PolygonMapRelate
PolygonMapUnion
SegmentMapVoronoi
SegmentMapTIN
SegmentMapDifference
SegmentMapSymetricDifference
SegmentMapUnion
SegmentMapIntersect
SegmentMapRelate
PointMapIntersect
PointMapDifference
PointMapSymetricDifference
PointMapUnion
PointMapRelation
PointMapPointInSegment
The buffer of a Point/Segment/Polygon at a distance r is the Polygon or MultiPolygon which contains all points within a distance d of the feature.
The operation has three parameters:
Input map |
Any polygon/point or segment map |
Buffer distance |
The distance of the points included. Positive and negative values are supported (dilation & erosion) |
End cap style | How the ends of lines are calculated |
The convex hull of a Point/Segment/Polygon is the smallest convex Polygon that contains all the points in the Point/Segment/Polygon (collection).
Syntax
PolygonMapConvexHull(InputMap, isCombined)
Input map | Any polygon/point or segment map |
isCombined |
Either create the convexhull over all the features or treat every element separately (which, in some case, might not make sense ) |
Calculates the difference between polygons in the two inputmaps. From Each polygon in the first input map the covering polygon(s) from the second input map, if any, is substracted.
(grey and orange lines are the boundaries of the original 2 polygons)
Syntax
PolygonMapDifference(Inputmap1, Inputmap2)
Inputmap1 |
PolygonMap |
Inputmap2 |
PolygonMap |
Calculates the symmetric difference between polygons in the two inputmaps. From Each polygon in the first input map the symmetric difference with any of the polygons from the secondmap is calculated
Syntax
PolygonMapSymetricDifference(Inputmap1, Inputmap2)
Inputmap1 |
PolygonMap |
Inputmap2 |
PolygonMap |
Calculate the intersection of a polygon of the input map with polygons of the output map. The map will be associated with an attribute table that contains the values of the original maps in a certain polygon.
(grey and orange lines are the boundaries of the original 2 polygons)
Syntax
PolygonMapIntersect((Inputmap1, Inputmap2)
Inputmap1 |
PolygonMap |
Inputmap2 |
PolygonMa |
For each polygon in the first inputmap a Boolean test is done to each feature in the second output map to see if it holds true. If so, the polygon is included in the output map.
The following relations are implemented
Contains |
returns true if this polygon contains the specified feature (excluding boundary). |
CoveredBy |
returns true if this polygon is covered by the specified feature. |
Crosses | returns true if this polygon crosses the specified feature. The features have some but not all interior points in common. |
Disjoint | returns true if this polygon is disjoint to the specified feature. The two features have no point in common. |
Equals | returns true if this polygon is equal to the specified feature. The two features have at least one point in common and no point of either feature lies in the exterior of the other feature. |
Intersects | returns true if this polygon intersects the specified feature. The two features have at least one point in common (intersect is the reverse of disjoint). |
Overlaps |
returns true if this polygon overlaps the specified feature. The features have some, but not all points in common. They have the same dimension and the intersection of the interiors of the two features has the same dimension as the features themselves. |
Touches | returns true if this polygon touches the specified geometry. The features have at least one point in common, but their interiors do not intersect. |
Within | returns true if this polygon is within the specified feature. Every point of this polygon is a point of the other feature and the interiors of the two features have at least one point in common. |
Example for “contains”; only polygons that contain the pointmap (yellow dots) are shown.
Syntax
PolygonMapRelate(inputmap1, Inputmap2, relation, negation)
Inputmap1 |
PolygonMap |
Inputmap2 | Polygon/Segment or Pointmap |
Relation | See table above |
Negation | The relation can be negated to give the opposite result(“true”,”false”) |
Merges polygons of the first input map with polygons of the second input map
The set operations for segments are identical for segmentmaps: SegmentMapIntersect, SegmentMapDifference, SegmentMapSymetricDifference, SegmentMapUnion, SegmentMapRelate. The only difference is that the set operations for segmentmaps can use a polygonmap (if it is not a segmentmap) as second inputmap. In such a case, the operation works on the boundaries of the polygonmap.
From a pointmap, it creates the segmentmap that forms the Voronoi map in which all points on the segments have equal distance to the closest points. Note that the “areas” are not closed, because the boundary segment at the edge of the map would, in theory, go on forever.
Syntax
PolygonMapRelate(Input Pointmap, minimal distance)
Input pointmap |
The input map used to calculate the voronoi boundaries. |
Minimal distance | The smallest distance which is used to calculate the boundaries. Points with a distance smaller than the minimum are not used in the calculation in relation to each other. |
Creates an irregular triangulated network from a input pointmap. This is a ‘bare bones’ implementation of a TIN and only deals with the creation of the segment map. Optionally it can choose to use conves hulls for elements at the edge of the TIN to create a better area filling.
Syntax
SegmentMapTIN(Input pointmap, use Convex hull)
Input pointmap |
The input map used to calculate the TIN |
Use convex hull | “True” or “False”. Determines if the TIN will cover the area defined by the convxhull of all the points in the input set. |
The set operations for pointmaps are identical for segmentmaps: PointMapIntersect, PointMapDifference, PointMapMapSymetricDifference, PointMapMapUnion, PointMapMapRelate. The only difference is pointmap intersect accepts Pointmaps, Segmentmaps or Polygonmaps as input. It will use the intersection of segments and boundaries to determine the intersection points.
A convenience application that determines a suitable point in a segment to determine its “middle”. This can be a real centroid, an existing vertex that is the best estimate or a point on of the edges that is closest to the centroid.
The three options in one map. Triangle=Centroid, Circle=Vertex, Diamond=MiddlePoint.
Syntax
PointMapPointInSegment(input segment map, option)
Input pointmap |
The input segment map |
Option | The option can be “Centroid”,”Vertex” or “MiddlePoint”. |
This is the second beta version of ILWIS 3.8. There is no proper installer, just copy the ilwis folder from the zip to the desired location. The main focus of this version has been visualization and the bulk of the changes can be found there. There are, however, additional significant changes.The list below contains the bulk of them.
Changes for Ilwis 3.8 beta-2 with respect to beta-1
MapWindow
General
Not yet finished
This is the first beta release. There is no proper installer, just copy the ilwis folder from the zip to the desired location. The focus of this version is visualization.
Changes for Ilwis 3.8 beta-1
Mapwindow
Available tools
Applications
Help files: now available as true HTML in the browser and can be located in the installation folder of ILWIS.
Operation List: (not tree) in the main window now has a finder edit box.
Domain Time: ILWIS now supports Time as a domain (Date + Time) as defined by ISO 8601.
Command Zip: makes a zip file of an ILWIS file plus all the support files it needs.
This release contains a number of important bug fixes for ILWIS 3.7.1:
New applications include:
New vector operations include:
PolygonMapBuffer
PolygonMapConvexHull
PolygonMapIntersect
PolygonMapDifference
PolygonMapSymetricDifference
PolygonMapRelate
PolygonMapUnion
SegmentMapVoronoi
SegmentMapTIN
SegmentMapDifference
SegmentMapSymetricDifference
SegmentMapUnion
SegmentMapIntersect
SegmentMapRelate
PointMapIntersect
PointMapDifference
PointMapSymetricDifference
PointMapUnion
PointMapRelation
PointMapPointInSegment
other changes:
WMS
Import
Export
Batch Command line processing
New features are:
The following functions and parameters now work properly:
The following bugs were fixed:
ILWIS 3.5 extends the functionality offered by ILWIS Open 3.4. New user features include:
New developer features include:
ILWIS 3.8.5 contains several new features and a number of bug fixes.
The following features were added:
Bug fixes:
ILWIS 3.8.4 contains a number of bug fixes, as well as a few new features.
Bug fixes include:
The following new features were added:
ILWIS 3.8.3 contains a number of bug fixes, as well as a few new features.
Bug fixes include:
New features:
ILWIS 3.8.2 introduces a few new features and improvements.
New features include:
Improvements:
ILWIS 3.8.1 has a few new features for ILWIS 3.8, as well as a number of bug fixes.
New features include
Problems solved
ILWIS 3.8 represents a major upgrade from ILWIS 3.7. Changes and improvements have mainly focussed on visualization, however, additional issues have been addressed.
Changes in ILWIS 3.8
Visualization
General
Layer tree
2D maps
3D Maps
Animations (formerly slide show)
New applications
General
ILWIS 3.8 represents a major upgrade from ILWIS 3.7. The main focus has been on visualization though some other issues have also been addressed. Please download the ILWIS 3.8 Visualization Reference Document.
New applications