Degrader doesn't work if a collimator based on ggmad or gdml is setting before degrader

[曾宪虎]

The degrader doesn’t work if there is solid before degreader (Some Geant4 geometry classes such as cons, trd, box based on ggmad)

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[Laurie Nevay]

Please can you attach a simple example that shows this.

The ggmad format isn’t currently supported or tested and is legacy code. The degrader is simple material, so the only reason I can see that it doesn’t ‘work’ is that there is an overlap in the geometry.

If you prefer to keep in the input private, you can email me at [e-mail].

[Laurie Nevay]

In the user's example, there were overlaps in the degrader geometry and other GGMAD geometry.

The overlaps in the degrader have been fixed and are now in release v1.4. In this case the degrader would have geometrical overlaps if over half closed resulting in bad tracking from Geant4 of the geometry and therefore inconsistent results.

The GGMAD geometry created an invisible container volume that was twice as big as it should be causing gross overlaps. This also results in bad tracking from Geant4. This has also been fixed v1.4.