Idyntree: Parsing a URDF <visual> or <collision> with the origin tag produces an invalid `link_H_geometry` transform

[traversaro]

If you parse a element such as:
~xml





~
the resulting link_H_geometry in the shape object is not initialized. If you just add a origin;
~xml






~
everything works fine.

[francesco-romano]

Because iDynTree::Transform does not initialise to identity by default.
Should be enough to either

• add a constructor to https://github.com/robotology/idyntree/blob/master/src/model_io/urdf/include/private/VisualElement.h#L37 or
• initialise it here: https://github.com/robotology/idyntree/blob/master/src/model_io/urdf/src/VisualElement.cpp#L26

[traversaro]

Because iDynTree::Transform does not initialise to identity by default.

Yes, that was a controversial decision but it proved to be necessary for performance (see https://github.com/robotology/idyntree/issues/98). Thanks for the quick suggestion!

[francesco-romano]

Yes, I remember that decision. But I always forget about it. During tests I caught a couple of these errors, but I think I missed this one.

I think it would be nice to run again #98 with more modern compiler and C++ stuff (like = default) to see how things have changed during time.

[ahoarau]

Any way we can have a demo on how to use/get/read/dostuff with the collision and visual elements ?

[traversaro]

Any way we can have a demo on how to use/get/read/dostuff with the collision and visual elements ?

Thanks for the suggestion, I opened a new issue at https://github.com/robotology/idyntree/issues/563 . Not sure if I can work on it in the next future, in the mean while there are some existing places in the codebase in which the API is used:

• https://github.com/robotology/idyntree/blob/c8bf721b771fa4b1e7c3a940632e121060719a19/src/visualization/src/ModelVisualization.cpp#L91
• https://github.com/robotology/idyntree/blob/c8bf721b771fa4b1e7c3a940632e121060719a19/src/model/src/ModelTransformers.cpp#L300