From eff934e8b593381d3adc0b6d68e73a3586290ad4 Mon Sep 17 00:00:00 2001
From: Uwe Oestermeier <u.oestermeier@iwm-tuebingen.de>
Date: Wed, 28 Apr 2021 17:02:54 +0200
Subject: [PATCH] Moved the addVelocity method after the transform to allow a
 modification of the delta within the transform method. To make this
 destructive side effect more explicit transform could return a modified
 value. But that could effect several projects.

---
 lib/scatter.js | 45 ++++++++++++++++++++++-----------------------
 1 file changed, 22 insertions(+), 23 deletions(-)

diff --git a/lib/scatter.js b/lib/scatter.js
index d9ae104..9e1e91f 100644
--- a/lib/scatter.js
+++ b/lib/scatter.js
@@ -44,8 +44,7 @@ const END = 'onEnd'
  */
 export class ScatterEvent extends BaseEvent {
     constructor(
-        target,
-        { translate = { x: 0, y: 0 }, scale = null, rotate = 0, about = null, fast = false, type = null } = {}
+        target, { translate = { x: 0, y: 0 }, scale = null, rotate = 0, about = null, fast = false, type = null } = {}
     ) {
         super('scatterTransformed', { target: target })
         this.translate = translate
@@ -106,7 +105,7 @@ class Throwable {
         this.velocity = null
         this.timestamp = null
         this.onThrowFinished = onThrowFinished
-        //console.log("onThrowFinished", onThrowFinished)
+            //console.log("onThrowFinished", onThrowFinished)
     }
 
     observeVelocity() {
@@ -184,7 +183,7 @@ class Throwable {
     animateThrow(time) {
         if (this.velocity != null) {
             let dt = this._throwDeltaTime()
-            // console.log("animateThrow", dt)
+                // console.log("animateThrow", dt)
             let next = this.nextVelocity(this.velocity)
             let prevLength = Points.length(this.velocity)
             let nextLength = Points.length(next)
@@ -382,7 +381,7 @@ export class AbstractScatter extends Throwable {
         let delta = interaction.delta()
 
         if (delta != null) {
-            this.addVelocity(delta)  // uo: reverted commit fa0256d782dd498c6d3e51321260ca375ca9f855
+
             let rotate = delta.rotate
             let zoom = delta.zoom
             if (this.maxRotation != null) {
@@ -403,6 +402,8 @@ export class AbstractScatter extends Throwable {
             }
 
             this.transform(delta, zoom, rotate, delta.about)
+            this.addVelocity(delta) // uo: reverted commit fa0256d782dd498c6d3e51321260ca375ca9f855
+
             if (zoom != 1) this.interactionAnchor = delta.about
         }
     }
@@ -467,8 +468,8 @@ export class AbstractScatter extends Throwable {
 
     keepOnStage(velocity, collision = 0.5) {
         let stagePolygon = this.containerPolygon
-        // UO: since keepOnStage is called in nextVelocity we need to
-        // ensure a return value
+            // UO: since keepOnStage is called in nextVelocity we need to
+            // ensure a return value
         if (!stagePolygon) return { x: 0, y: 0 }
         let polygon = this.polygon
         let bounced = this.bouncing()
@@ -479,7 +480,7 @@ export class AbstractScatter extends Throwable {
             let dx = this.movableX ? velocity.x : 0
             let dy = this.movableY ? velocity.y : 0
             let factor = this.throwDamping
-            // if (recentered) {
+                // if (recentered) {
             if (x < 0) {
                 dx = -dx
                 factor = collision
@@ -515,10 +516,10 @@ export class AbstractScatter extends Throwable {
                     onComplete: this.close.bind(this)
                 })
             } else if (this.scale < this.minScale + this.scaleCloseThreshold) {
-                this.zoom(this.minScale + this.scaleCloseThreshold, {
-                    animate: 0.4
-                })
-            }
+            this.zoom(this.minScale + this.scaleCloseThreshold, {
+                animate: 0.4
+            })
+        }
     }
 
     rotateDegrees(degrees, anchor) {
@@ -621,7 +622,7 @@ export class AbstractScatter extends Throwable {
         let newOrigin = Points.arc(anchor, beta + rotate, distance * thresholdedZoom)
         let extra = Points.subtract(newOrigin, origin)
         const anchorOffset = Points.subtract(anchor, origin)
-        // this._move(offset)
+            // this._move(offset)
         this.scale = newScale
         this.rotation += rotate
         let offset = Points.negate(anchorOffset)
@@ -911,8 +912,7 @@ export class DOMScatterContainer {
      * @param {DOM node} debugCanvas - Shows debug infos about touches if not null
      */
     constructor(
-        element,
-        {
+        element, {
             stopEvents = 'auto',
             claimEvents = true,
             useCapture = true,
@@ -1076,8 +1076,7 @@ export class DOMScatterContainer {
 export class DOMScatter extends AbstractScatter {
     constructor(
         element,
-        container,
-        {
+        container, {
             startScale = 1.0,
             minScale = 0.1,
             maxScale = 1.0,
@@ -1274,10 +1273,10 @@ export class DOMScatter extends AbstractScatter {
         let r = this.bounds
         let w2 = r.width / 2
         let h2 = r.height / 2
-        //   if (this.resizable) {
-        //             w2 *= this.scale
-        //             h2 *= this.scale
-        //         }
+            //   if (this.resizable) {
+            //             w2 *= this.scale
+            //             h2 *= this.scale
+            //         }
         var x = r.left + w2
         var y = r.top + h2
         return { x, y }
@@ -1397,7 +1396,7 @@ export class DOMScatter extends AbstractScatter {
         }
         this._x = x
         this._y = y
-        // this.addVelocity({ x: delta.x, y: delta.y }) uo: reverted commit fa0256d782dd498c6d3e51321260ca375ca9f855
+            // this.addVelocity({ x: delta.x, y: delta.y }) uo: reverted commit fa0256d782dd498c6d3e51321260ca375ca9f855
         TweenLite.set(this.element, { x, y })
     }
 
@@ -1504,4 +1503,4 @@ export class DOMScatter extends AbstractScatter {
     }
 }
 
-DOMScatter.zIndex = 1000
+DOMScatter.zIndex = 1000
\ No newline at end of file