Bug 576057

Description Laurent Redor 2021-09-17 06:28:43 EDT

Created attachment 287155 [details]
diffBeforeAfterZOrder.png

Since bug 574273, some diagrams are not drawn exactly as before.

This is "normal" because before, the edges are drawn according to the creation order of their sources. Now, they are drawn according to the creation order of edges.
In the file "diffBeforeAfterZOrder.png", you can see 4 cases:
* Case A: The order of creation of source nodes is the same than the order of creation of edges. For information, the numbers suffixing nodes and edges correspond to the creation order.
    * The display result is the same before and after the new feature concerning z-order.
* Case B: The order of creation of source nodes is not the same than the order of creation of edges. For information, the numbers suffixing nodes and edges correspond to the creation order.
    * The display result is not the same before and after the new feature concerning z-order. So the jumplink is not on the same edge.
* Case C: The order of creation of source nodes is the same than the order of creation of edges. For information, the numbers suffixing nodes and edges correspond to the creation order. In this case, both edges have not bendpoints constraint in model. "c4" has only a bendpoint, added graphically, to avoid an overlap between "c3" and "c4".
    * The display result is the same before and after the new feature concerning z-order.
* Case D: The order of creation of source nodes is not the same than the order of creation of edges. For information, the numbers suffixing nodes and edges correspond to the creation order. In this case, both edges have not bendpoints constraint in model. "d3" has only a bendpoint, added graphically, to avoid an overlap between "d3" and "d4".
    * The display result is not the same before and after the new feature concerning z-order. After the z-order feature, "d3" is drawn in first so without bendpoint and "d4" is drawn in second so with a "graphical bendpoint".
	
The project JumpLinksTest-zOrderRegression.zip contains the diagram used for the above screenshot. After the fix of the issue, the diagram should be drawn as before the feature concerning z-order.

A migration participant must be added to "sort" GMF edges list according to the nodes order.