Concave VTP-Polygon problem

[totalrain]

Hi Luis,

I am having problems with concave VTP polygons in SBuilder V2.01. The polygons are in Shape files converted to BLN format and then appended to a SBuilder project.

The first image shows a polygon in Sbuilder



The second image shows the same polygon as displayed by LWMViewer which opens the compiled VTP*.bgl file, and displays the triangles.




As can be seen the polygon is incorrectly generated.

I am currently getting around this problem by inspecting the generated polygons and then manually splitting the affected polygons until the compiled results are correct. This is painstaking and time consuming, but does get arround the problem.

However, not all concave polygons are affected. It appears your VTP polygon algorithm isn't handling all concave polygons correctly.

This is meant to be informative and not a criticism. I am getting some great results using your program. Thanks again for a great utility.

[Jan Nielsen]

Hi,
I had this problem when I started using the program. I produced BLN files from Autocad DXF files converted to BLN with the free dxf2xyz utility. I realized that I had to start drawing the polygons from a start point from where you could see all the other vertexes in that polygon. E.g., no broken or intersected lines from the staring point to any of the other vertexes. That way I had no problems with the up splitting into triangles performed by the program.

Best regards Jan

Btw any new updates now Luis? [:)]