[442289] Improve gap computation

Currently, the gap is rounded to the lower Integer. So the last gap can
be different. To minimize the delta between the last gap and the others,
the gap is now rounded up to the lower Integer if the remainder is less
than or equal to 0.5 and higher integer if the remainder is greater than
0.5.

Bug: 442289
Change-Id: Ia1c234af77157abc6f61bf4aa28498ddb721f494
Signed-off-by: Laurent Redor <laurent.redor@obeo.fr>

1 files changed, 8 insertions, 2 deletions

diff --git a/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/internal/edit/commands/DistributeCommand.java b/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/internal/edit/commands/DistributeCommand.java
index f86ab89539..8b970dd664 100644
--- a/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/internal/edit/commands/DistributeCommand.java
+++ b/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/internal/edit/commands/DistributeCommand.java
@@ -422,7 +422,10 @@ public class DistributeCommand extends AbstractTransactionalCommand {
                                 availableSpace -= getSizeFunction.apply(part);
                             }
                         }
-                        return availableSpace / (partsToDistribute.size() - 1);
+                        // Gap is rounded up to the lower Integer if the
+                        // remainder is less than or equal to 0.5 and higher
+                        // integer if the remainder is greater than 0.5.
+                        return Math.round(((float) availableSpace) / (partsToDistribute.size() - 1));
                     }
                 });
     }
@@ -470,7 +473,10 @@ public class DistributeCommand extends AbstractTransactionalCommand {
                 new GetGapFunction(partsToDistribute, getMainAxisFunction, getMainAxisFunction, getSizeFunction) {
                     @Override
                     public int apply(IGraphicalEditPart firstPart, IGraphicalEditPart lastPart) {
-                        return (getFirstPartMainAxisFunction.apply(lastPart) - getLastPartMainAxisFunction.apply(firstPart)) / (partsToDistribute.size() - 1);
+                        // Gap is rounded up to the lower Integer if the
+                        // remainder is less than or equal to 0.5 and higher
+                        // integer if the remainder is greater than 0.5.
+                        return Math.round(((float) (getFirstPartMainAxisFunction.apply(lastPart) - getLastPartMainAxisFunction.apply(firstPart))) / (partsToDistribute.size() - 1));
                     }
                 });
     }