Using toJava2D() with group shapes

[istinnstudio]

Hi..
I am trying to figure how to implement PGS calculations in native Path2D in pure Java, not processing. Not having seen any relative examples I have made a simple method to triangulate a path2D just to see how things work but I get an error in casting, it seems that there is an other internal conversion taking place using JTS library. The question is how to implement the intermediate conversion as I guess the "Shape interface" and Path2D needs casting. The example is random, it would be nice if have some basic examples for other geometric calculations also. The code is as simple as it can get:

    public Path2D performDelaunayTriangulationUsingPGS(Path2D path) {
       PShape pshape = new PShape();  // or PShape.GEOMETRY it seems like the constructor is dependent on JTS
       pshape = fromJava2D(path); // Convert Path2D to PShape
        // Perform Delaunay Triangulation using the PGS library or other implementation
       pshape = delaunayTriangulation(pshape);
        // Convert the triangulated PShape back to Path2D
        Path2D triangulatedPath =  (Path2D) toJava2D(pshape); // casting with error
        return triangulatedPath;
    }
}

SEVERE: null
java.lang.ClassCastException: class org.locationtech.jts.awt.GeometryCollectionShape cannot be cast to class java.awt.geom.Path2D (org.locationtech.jts.awt.GeometryCollectionShape is in unnamed module of loader 'app'; java.awt.geom.Path2D is in module java.desktop of loader 'bootstrap')

[micycle1]

The output of the triangulation is a group-type PShape, which consists of multiple child shapes, each representing a triangle in the triangulated geometry.

The toJava2D() method converts group shapes (multipolygons) to a JTS GeometryCollectionShape type, which implements java.awt.shape. However, since the original shape contains multiple paths, it cannot be directly converted to a Path2D.

To work with the triangulation, you have two options:

1. Cast the output of toJava2D() to a (GeometryCollectionShape) instead, and then use its getPathIterator() method...
2. Iterate over the child PShapes of the triangulation. For each child, you can call toJava2D() that should return a Path2D representing the individual triangle. By iterating over all the child shapes, you can obtain separate Path2D objects for each triangle and work with them individually.

[istinnstudio]

thanks! for the reply, it is clear now, it seems a bit more complicated than I initially have thought, but I will give it a try, probably by creating lists of path2D objects through GeometryCollectionShape. If I will figure out a solution I will post it here.