[the-board] [ui] Add ability to move multiple things at once

[Lucas Rocha <lucasr src gnome org>]

commit 90f69e467ec1995184b0b264a38d451d0345826c
Author: Lucas Rocha <lucasr gnome org>
Date:   Thu Jan 13 21:44:08 2011 +0000

    [ui] Add ability to move multiple things at once

 src/js/ui/page.js  |   89 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/js/ui/thing.js |    7 ----
 2 files changed, 89 insertions(+), 7 deletions(-)
---
diff --git a/src/js/ui/page.js b/src/js/ui/page.js
index de2e9ea..78deadd 100644
--- a/src/js/ui/page.js
+++ b/src/js/ui/page.js
@@ -11,6 +11,9 @@ const Clutter = imports.gi.Clutter;
 const Background = imports.ui.background;
 const Thing = imports.ui.thing;
 
+// util imports
+const MathUtil = imports.util.mathUtil;
+
 // model imports
 const PageModel = imports.model.pageModel;
 
@@ -273,6 +276,10 @@ Page.prototype = {
             thing.connect("drag-begin",
                           Lang.bind(this, this._onThingDragBegin));
 
+        thing._Page_dragMotionId =
+            thing.connect("drag-motion",
+                          Lang.bind(this, this._onThingDragMotion));
+
         thing._Page_dragEndId =
             thing.connect("drag-end",
                           Lang.bind(this, this._onThingDragEnd));
@@ -352,6 +359,26 @@ Page.prototype = {
                            transition: _ADD_THING_TRANSITION });
     },
 
+    _areaUnion : function(area1, area2) {
+        let union = { x1: 0,
+                      y1: 0,
+                      x2: 0,
+                      y2: 0 };
+
+        if (area1 && area2) {
+            union.x1 = Math.min(area1.x1, area2.x1);
+            union.y1 = Math.min(area1.y1, area2.y1);
+            union.x2 = Math.max(area1.x2, area2.x2);
+            union.y2 = Math.max(area1.y2, area2.y2);
+        } else if (area1) {
+            union = area1;
+        } else if (area2) {
+            union = area2;
+        }
+
+        return union;
+    },
+
     _updateSelectedThings : function() {
         if (this._selectionBox.visible) {
             let x1 = this._selectionBox.x - this._selectionBox.anchorX;
@@ -362,10 +389,23 @@ Page.prototype = {
             this._selectedThings = this._getThingsInArea(x1, y1, x2, y2);
         } else {
             this._selectedThings = [];
+            delete this._dragArea;
         }
 
         let updateSelection = function(thing) {
             thing.selected = this._selectedThings.indexOf(thing) >= 0;
+
+            if (thing.selected) {
+                let state = thing.onGetState();
+
+                let thingArea = { x1: state.x,
+                                  y1: state.y,
+                                  x2: state.x + state.width,
+                                  y2: state.y + state.height };
+
+                this._dragArea =
+                    this._areaUnion(this._dragArea, thingArea);
+            }
         };
 
         this._things.forEach(Lang.bind(this, updateSelection));
@@ -376,6 +416,17 @@ Page.prototype = {
         this._updateSelectedThings();
     },
 
+    _ensureDragArea : function(draggedThing) {
+        if (!this._dragArea) {
+            let state = draggedThing.onGetState();
+
+            this._dragArea = { x1: state.x,
+                               y1: state.y,
+                               x2: state.x + state.width,
+                               y2: state.y + state.height };
+        }
+    },
+
     _onMainBoxClicked : function(o, event) {
         if (this._cancelSelectionOnClick) {
             this._unselectAllThings();
@@ -444,11 +495,48 @@ Page.prototype = {
     _onThingDragBegin : function(thing) {
         thing.actor.raise(null);
 
+        this._ensureDragArea(thing);
+
         if (this._activeThing && this._activeThing != thing) {
             this.setActiveThing(null);
         }
     },
 
+    _onThingDragMotion : function(thing, deltaX, deltaY) {
+        let minDeltaX = -this._dragArea.x1;
+        let maxDeltaX = this._mainBox.allocation.x2 -
+                        this._mainBox.allocation.x1 -
+                        this._dragArea.x2;
+
+        let minDeltaY = -this._dragArea.y1;
+        let maxDeltaY = this._mainBox.allocation.y2 -
+                        this._mainBox.allocation.y1 -
+                        this._dragArea.y2;
+
+        deltaX = MathUtil.clamp(deltaX, minDeltaX, maxDeltaX);
+        deltaY = MathUtil.clamp(deltaY, minDeltaY, maxDeltaY);
+
+        this._dragArea.x1 += deltaX;
+        this._dragArea.x2 += deltaX;
+        this._dragArea.y1 += deltaY;
+        this._dragArea.y2 += deltaY;
+
+        let moveThing = function(thingToMove) {
+            let state = thingToMove.onGetState();
+
+            let newX = state.x + deltaX;
+            let newY = state.y + deltaY;
+
+            thingToMove.setPosition(newX, newY);
+        };
+
+        if (!thing.selected) {
+            moveThing(thing);
+        }
+
+        this._selectedThings.forEach(moveThing);
+    },
+
     _onThingDragEnd : function(thing) {
         if (this._activeThing !== thing) {
             thing.actor.lower(this._dimBox);
@@ -526,6 +614,7 @@ Page.prototype = {
         thing.disconnect(thing._Page_activateId);
         thing.disconnect(thing._Page_deactivateId);
         thing.disconnect(thing._Page_dragBeginId);
+        thing.disconnect(thing._Page_dragMotionId);
         thing.disconnect(thing._Page_dragEndId);
         thing.disconnect(thing._Page_removeId);
         thing.disconnect(thing._Page_saveId);
diff --git a/src/js/ui/thing.js b/src/js/ui/thing.js
index 5e3781f..ac81684 100644
--- a/src/js/ui/thing.js
+++ b/src/js/ui/thing.js
@@ -320,13 +320,6 @@ Thing.prototype = {
 
     _onMainBoxDragMotion : function(action, actor, deltaX, deltaY) {
         Tb.signal_stop_emission_by_name(action, "drag-motion");
-
-        let newX = this._mainBox.x + deltaX;
-        let newY = this._mainBox.y + deltaY;
-
-        this._updatePosition(newX, newY,
-                             false /* not from state */);
-
         this.emit("drag-motion", deltaX, deltaY);
     },