World coordinates when cdp is not defined
We believe that this case is unlikely to happen in real files, but wanted to point that out anyway.
When file has no cdp information, asking for information in World coordinates returns data in Annotation coordinate system. If transformation with missing World coordinates is impossible, I would have expected some error message along the way.
SEGY without_cdp.segy:
spec.samples = [4, 8]
spec.ilines = [3, 4, 5]
spec.xlines = [10, 11]
DelayRecordingTime: 5,
openvds:
auto transformer = OpenVDS::IJKCoordinateTransformer(layout);
auto annotation = transformer.IJKIndexToAnnotation({0, 0, 0})
auto world = transformer.IJKIndexToWorld({ 0, 0, 0 });
Result:
Annotation: 3 10 5
World: 3 10 -5
World coordinates created from transformed I/J are same as annotation, which is misleading.
World coordinate created from transformed K is -Time
(also in files with cdp), which seems strange, though somewhat understandable.