From 0b8bccc8d4cbeba6e3b5a9a413cd066c27da33fb Mon Sep 17 00:00:00 2001
From: James Swaine <james.swaine@gmail.com>
Date: Thu, 19 Jul 2012 17:05:04 -0500
Subject: [PATCH] Future visualizer - only redraw overlay when moused-over
 event changes

---
 collects/future-visualizer/private/pict-canvas.rkt   |  2 +-
 .../future-visualizer/private/visualizer-gui.rkt     | 12 ++++++++----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/collects/future-visualizer/private/pict-canvas.rkt b/collects/future-visualizer/private/pict-canvas.rkt
index f45fd8b884..f2115e5efd 100644
--- a/collects/future-visualizer/private/pict-canvas.rkt
+++ b/collects/future-visualizer/private/pict-canvas.rkt
@@ -83,7 +83,7 @@
                                         (set! needs-redraw #t)
                                         (redraw-the-bitmap/maybe-delayed! (get-viewable-region) #:only-the-overlay? only-the-overlay?) 
                                         (set! repainting? #t)
-                                        (refresh))]
+                                        (refresh))] 
               [interval 100] 
               [just-once? #t]) 
          (set! delaying-redraw #t)]))
diff --git a/collects/future-visualizer/private/visualizer-gui.rkt b/collects/future-visualizer/private/visualizer-gui.rkt
index 5ac8f0039b..7c02681dde 100644
--- a/collects/future-visualizer/private/visualizer-gui.rkt
+++ b/collects/future-visualizer/private/visualizer-gui.rkt
@@ -71,7 +71,7 @@
            (send data-label1 set-label (format "Touching future ~a" (event-user-data evt)))]
           [else 
            (send data-label1 set-label "")
-           (send data-label2 set-label "")])) 
+           (send data-label2 set-label "")]))  
       (begin 
         (send selected-label set-label "") 
         (send time-label set-label "") 
@@ -152,9 +152,13 @@
                               [parent timeline-container]
                               [pict-builder (λ (vregion) (timeline-pict-for-trace-data vregion the-trace frameinfo segments))] 
                               [hover-handler (λ (x y vregion) 
-                                               (let ([seg (find-seg-for-coords x y timeline-mouse-index)]) 
-                                                 (set! hover-seg seg) 
-                                                 (post-event listener-table 'segment-hover timeline-panel seg)))]
+                                               (let ([seg (find-seg-for-coords x y timeline-mouse-index)])
+                                                 (cond 
+                                                   [(equal? seg hover-seg) #f] 
+                                                   [else 
+                                                    (set! hover-seg seg) 
+                                                    (post-event listener-table 'segment-hover timeline-panel seg) 
+                                                    #t])))]
                               [click-handler (λ (x y vregion) 
                                                (let ([seg (find-seg-for-coords x y timeline-mouse-index)]) 
                                                  (set! tacked-seg seg)