track the canvas top left position instead of the center position to figure out when to translate the subpath per canvas translation...this one seems to not drift (no floating point issues uncovered so far)

1 files changed, 23 insertions, 22 deletions

diff --git a/js/lib/geom/sub-path.js b/js/lib/geom/sub-path.js
index 4ded360c..d8d74928 100755
--- a/js/lib/geom/sub-path.js
+++ b/js/lib/geom/sub-path.js
@@ -72,9 +72,9 @@ var GLSubpath = function GLSubpath() {
     //the canvas that will draw this subpath
     this._canvas = null;
     
-    //the X and Y location of this subpath's canvas in stage world space of Ninja
-    this._canvasX = 0;
-    this._canvasY = 0;
+    //the top left location of this subpath's canvas in screen space
+    this._canvasLeft = 0;
+    this._canvasTop = 0;
 
     //stroke information
     this._strokeWidth = 1.0;
@@ -362,20 +362,20 @@ GLSubpath.prototype.setPlaneCenter = function(pc){
     this._planeCenter = pc;
 };
 
-GLSubpath.prototype.getCanvasX = function(){
-    return this._canvasX;
+GLSubpath.prototype.getCanvasLeft = function(){
+    return this._canvasLeft;
 };
 
-GLSubpath.prototype.getCanvasY = function(){
-    return this._canvasY;
+GLSubpath.prototype.getCanvasTop = function(){
+    return this._canvasTop;
 };
 
-GLSubpath.prototype.setCanvasX = function(cx){
-    this._canvasX=cx;
+GLSubpath.prototype.setCanvasLeft = function(cx){
+    this._canvasLeft=cx;
 };
 
-GLSubpath.prototype.setCanvasY = function(cy){
-    this._canvasY=cy;
+GLSubpath.prototype.setCanvasTop = function(cy){
+    this._canvasTop=cy;
 };
 
 GLSubpath.prototype.getIsClosed = function () {
@@ -868,20 +868,17 @@ GLSubpath.prototype.getStrokeWidth = function () {
 
 GLSubpath.prototype.translateSubpathPerCanvas = function(elemMediator){
     //check if the canvas was translated
-    var penCanvasLeft = parseInt(elemMediator.getProperty(this._canvas, "left"));//parseFloat(DocumentControllerModule.DocumentController.GetElementStyle(this._penCanvas, "left"));
-    var penCanvasTop = parseInt(elemMediator.getProperty(this._canvas, "top"));//parseFloat(DocumentControllerModule.DocumentController.GetElementStyle(this._penCanvas, "top"));
-    var penCanvasWidth = parseInt(elemMediator.getProperty(this._canvas, "width"));//this._penCanvas.width;
-    var penCanvasHeight = parseInt(elemMediator.getProperty(this._canvas, "height"));//this._penCanvas.height;
-    var penCanvasOldX = penCanvasLeft + 0.5 * penCanvasWidth;
-    var penCanvasOldY = penCanvasTop + 0.5 * penCanvasHeight;
+    var penCanvasCurrentLeft = parseInt(elemMediator.getProperty(this._canvas, "left"));//parseFloat(DocumentControllerModule.DocumentController.GetElementStyle(this._penCanvas, "left"));
+    var penCanvasCurrentTop = parseInt(elemMediator.getProperty(this._canvas, "top"));//parseFloat(DocumentControllerModule.DocumentController.GetElementStyle(this._penCanvas, "top"));
 
-    var translateCanvasX = penCanvasOldX - this._canvasX;
-    var translateCanvasY = penCanvasOldY - this._canvasY;
+    var translateCanvasX = Math.round(penCanvasCurrentLeft - this._canvasLeft);
+    var translateCanvasY = Math.round(penCanvasCurrentTop - this._canvasTop);
 
-    //update the canvasX and canvasY parameters for this subpath and also translate the subpath points (since they're stored in stage world space)
+    //update the left and top parameters for this subpath and also translate the subpath points (since they're stored in stage world space)
     if (Math.abs(translateCanvasX)>=1 || Math.abs(translateCanvasY)>=1){
-        this.setCanvasX(translateCanvasX + this._canvasX);
-        this.setCanvasY(translateCanvasY + this._canvasY);
+        this.setCanvasLeft(penCanvasCurrentLeft);
+        this.setCanvasTop(penCanvasCurrentTop);
+        //todo does the canvas translation correspond to the translation in stage world space? 
         this.translateAnchors(translateCanvasX, translateCanvasY, 0);
     }
     this._dirty=true;
@@ -896,6 +893,8 @@ GLSubpath.prototype.setStrokeWidth = function (w) {
     this._dirty=true;
 
     var ElementMediator = require("js/mediators/element-mediator").ElementMediator;
+
+    //translate the subpath in case the actual canvas location does not match where subpath thinks the canvas should be
     this.translateSubpathPerCanvas(ElementMediator);
 
     // **** adjust the left, top, width, and height to adjust for the change in stroke width ****
@@ -920,6 +919,8 @@ GLSubpath.prototype.setStrokeWidth = function (w) {
     ElementMediator.setProperty(canvasArray, "height", [bboxHeight+"px"], "Changing", "penTool");//canvas.height = h;
     ElementMediator.setProperty(canvasArray, "left", [left+"px"],"Changing", "penTool");//DocumentControllerModule.DocumentController.SetElementStyle(canvas, "left", parseInt(left) + "px");
     ElementMediator.setProperty(canvasArray, "top", [top + "px"],"Changing", "penTool");//DocumentControllerModule.DocumentController.SetElementStyle(canvas, "top", parseInt(top) + "px");
+    this.setCanvasLeft(left);
+    this.setCanvasTop(top);
 };
 
 GLSubpath.prototype.getStrokeMaterial = function () {