Recalculate edge properties when shapes are refreshed

Shape sizes can change (if you're actively editing a shape), which can
mean that some edge properties need to be recalculated.

We do this at the graph, rather than edge, level to avoid the overhead
of installing a notification for every single edge.

3 files changed, 29 insertions, 0 deletions

diff --git a/tikzit/src/common/Edge.h b/tikzit/src/common/Edge.h
index 64da138..accf38c 100644
--- a/tikzit/src/common/Edge.h
+++ b/tikzit/src/common/Edge.h
@@ -274,6 +274,11 @@ typedef enum {
 - (id)initWithSource:(Node*)s andTarget:(Node*)t;
 
 /*!
+ @brief      Force the recalculation of the derived properties.
+ */
+- (void)recalculateProperties;
+
+/*!
  @brief      Recompute the control points and midpoint.
  */
 - (void)updateControls;
diff --git a/tikzit/src/common/Edge.m b/tikzit/src/common/Edge.m
index ea20d2a..ba80aef 100644
--- a/tikzit/src/common/Edge.m
+++ b/tikzit/src/common/Edge.m
@@ -127,6 +127,10 @@
 	return NSMakePoint (pt.x + dx, pt.y + dy);
 }
 
+- (void)recalculateProperties {
+	dirty = YES;
+}
+
 - (void)updateControls {
 	// check for external modification to the node locations
 	if (src.x != [source point].x || src.y != [source point].y ||
diff --git a/tikzit/src/common/Graph.m b/tikzit/src/common/Graph.m
index 33a81f6..258ece4 100644
--- a/tikzit/src/common/Graph.m
+++ b/tikzit/src/common/Graph.m
@@ -23,6 +23,11 @@
 
 #import "Graph.h"
 #import "TikzGraphAssembler.h"
+#import "Shape.h"
+
+@interface Graph (Private)
+- (void) shapeDictionaryReplaced:(NSNotification*)notification;
+@end
 
 @implementation Graph
 
@@ -36,6 +41,11 @@
 		edges = [[NSMutableArray alloc] initWithCapacity:10];
 		inEdges = nil;
 		outEdges = nil;
+		[[NSNotificationCenter defaultCenter]
+		        addObserver:self
+		           selector:@selector(shapeDictionaryReplaced:)
+		               name:@"ShapeDictionaryReplaced"
+		             object:[Shape class]];
 	}
 	return self;
 }
@@ -56,6 +66,8 @@
 }
 
 - (void)dealloc {
+	[[NSNotificationCenter defaultCenter] removeObserver:self];
+
 	[graphLock lock];
 	[inEdges release];
 	[outEdges release];
@@ -837,4 +849,12 @@
 
 @end
 
+@implementation Graph (Private)
+- (void) shapeDictionaryReplaced:(NSNotification*)notification {
+	for (Edge *e in edges) {
+		[e recalculateProperties];
+	}
+}
+@end
+
 // vi:ft=objc:ts=4:noet:sts=4:sw=4