"addPointToPolygon"

Adds a point to a polygon.

Synopsis

void addPointToPolygon(string strLayer, int iPolygonIndex, int iIndex, double dX, double dY);

Parameters

Parameter Description
strLayer The Layer the point will be added to.
iPolygonIndex The index of the polygon that was added to a layer. The return value of the function "addPolygonToLayer".
iIndex The index refers to the points in the polygon and starts at 0.
dX The x coordinate. The coordinate should fit the coordinate system of the map being displayed.
dY The y coordinate. The coordinate should fit the coordinate system of the map being displayed.

Description

Adds a point to a polygon.

Example

A polygon with four points is added to a layer.

main()
{
  int i;
  GisViewer_ewo1.addEmptyLayer("POL");
  GisViewer_ewo1.setLayerFillColor("POL","blue");
  i = GisViewer_ewo1.addPolygonToLayer("POL","POLI", 4);
  GisViewer_ewo1.addPointToPolygon("POL", i, 0, 25, 60); /*Add the first point to the polygon*/
  GisViewer_ewo1.addPointToPolygon("POL", i, 1, 26, 61); /*Add the second point to the polygon*/
  GisViewer_ewo1.addPointToPolygon("POL", i, 2, 24, 62);
  GisViewer_ewo1.addPointToPolygon("POL", i, 3, 25, 60);
}

The code above adds a polygon above Helsinki, Finland.

The layer the polygon will be added to must be a layer that was added using the function "addEmptyLayer". The function addPolygonToLayer() is not supported on an existing 'normal' layer.

Assignment

GIS Viewer