From 40f3fc5feae866c99af818a886e8bf9d8cf2b8dd Mon Sep 17 00:00:00 2001
From: Pushkar Joshi
Date: Tue, 6 Mar 2012 17:23:58 -0800
Subject: merge Valerio's architecture changes into pen tool

---
 js/lib/geom/sub-path.js | 84 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

(limited to 'js/lib/geom')

diff --git a/js/lib/geom/sub-path.js b/js/lib/geom/sub-path.js
index ab54d1e9..0a65511b 100755
--- a/js/lib/geom/sub-path.js
+++ b/js/lib/geom/sub-path.js
@@ -584,6 +584,90 @@ GLSubpath.prototype.pickAnchor = function (pickX, pickY, pickZ, radius) {
     return selAnchorIndex;
 };
 
+GLSubpath.prototype.isWithinBBox =function(x,y,z){
+    if (this._BBoxMin[0]>x || this._BBoxMin[1]>y || this._BBoxMin[2]>z){
+        return false;
+    }
+    if (this._BBoxMax[0]<x || this._BBoxMax[1]<y || this._BBoxMax[2]<z){
+        return false;
+    }
+    return true;
+}
+
+//pick the path point closest to the specified location, return null if some anchor point (or its handles) is within radius, else return the parameter distance
+GLSubpath.prototype.pathHitTest = function (pickX, pickY, pickZ, radius) {
+    var numAnchors = this._Anchors.length;
+    var selAnchorIndex = -1;
+    var retParam = null;
+    var radSq = radius * radius;
+    var minDistance = Infinity;
+
+    //check if the location is close to the currently selected anchor position
+    if (this._selectedAnchorIndex>=0 && this._selectedAnchorIndex<this._Anchors.length){
+        var distSq = this._Anchors[this._selectedAnchorIndex].getDistanceSq(pickX, pickY, pickZ);
+        //check the anchor point
+        if (distSq < minDistance && distSq < radSq) {
+            selAnchorIndex = this._selectedAnchorIndex;
+            minDistance = distSq;
+        }
+    }
+    //check the prev and next of the selected anchor if the above did not register a hit
+    if (this._selectedAnchorIndex>=0 && selAnchorIndex === -1) {
+        var distSq = this._Anchors[this._selectedAnchorIndex].getPrevDistanceSq(pickX, pickY, pickZ);
+        if (distSq < minDistance && distSq < radSq){
+            selAnchorIndex = this._selectedAnchorIndex;
+            minDistance = distSq;
+        } else {
+            //check the next for this anchor point
+            distSq = this._Anchors[this._selectedAnchorIndex].getNextDistanceSq(pickX, pickY, pickZ);
+            if (distSq<minDistance && distSq<radSq){
+                selAnchorIndex = this._selectedAnchorIndex;
+                minDistance = distSq;
+            }
+        }
+    }
+
+    //now check if the location is close to any anchor position
+    if (selAnchorIndex===-1) {
+        for (var i = 0; i < numAnchors; i++) {
+            var distSq = this._Anchors[i].getDistanceSq(pickX, pickY, pickZ);
+            //check the anchor point
+            if (distSq < minDistance && distSq < radSq) {
+                selAnchorIndex = i;
+                minDistance = distSq;
+            }
+        }//for every anchor i
+    }
+
+    //finally check if the location is close to the curve itself
+    if (selAnchorIndex===-1) {
+        //first check if the input location is within the bounding box
+        if (this.isWithinBBox(pickX,pickY,pickZ)){
+            var numSegments = this._isClosed ? numAnchors : numAnchors-1;
+            for (var i = 0; i < numSegments; i++) {
+                var nextIndex = (i+1)%numAnchors;
+                //check if the point is close to the bezier segment between anchor i and anchor nextIndex
+                var controlPoints = [[this._Anchors[i].getPosX(),this._Anchors[i].getPosY(),this._Anchors[i].getPosZ()],
+                    [this._Anchors[i].getNextX(),this._Anchors[i].getNextY(),this._Anchors[i].getNextZ()],
+                    [this._Anchors[nextIndex].getPrevX(),this._Anchors[nextIndex].getPrevY(),this._Anchors[nextIndex].getPrevZ()],
+                    [this._Anchors[nextIndex].getPosX(),this._Anchors[nextIndex].getPosY(),this._Anchors[nextIndex].getPosZ()]];
+                var point = [pickX, pickY, pickZ];
+                if (this._isWithinBoundingBox(point, controlPoints, radius)) {
+                    //var intersectParam = this._checkIntersection(controlPoints, 0.0, 1.0, point, radius);
+                    var intersectParam = this._checkIntersectionWithSamples(this._anchorSampleIndex[i], this._anchorSampleIndex[nextIndex], point, radius);
+                    console.log("intersectParam:"+intersectParam);
+                    if (intersectParam){
+                        selAnchorIndex=i;
+                        retParam = intersectParam-i; //make the retParam go from 0 to 1
+                        break;
+                    }
+                }
+            }//for every anchor i
+        }//if is within bbox
+    }
+    return [selAnchorIndex,retParam];
+}     //GLSubpath.pathHitTest function
+
 //pick the path point closest to the specified location, return null if some anchor point (or its handles) is within radius, else return the parameter distance
 GLSubpath.prototype.pickPath = function (pickX, pickY, pickZ, radius) {
     var numAnchors = this._Anchors.length;
-- 
cgit v1.2.3


From 353bfa04a6153b0146a0c73b6e6bb0e5f4b23194 Mon Sep 17 00:00:00 2001
From: Pushkar Joshi
Date: Tue, 6 Mar 2012 17:40:22 -0800
Subject: merge Valerio's architecture changes

---
 js/lib/geom/brush-stroke.js | 177 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 172 insertions(+), 5 deletions(-)

(limited to 'js/lib/geom')

diff --git a/js/lib/geom/brush-stroke.js b/js/lib/geom/brush-stroke.js
index 9a934928..39af5c5c 100755
--- a/js/lib/geom/brush-stroke.js
+++ b/js/lib/geom/brush-stroke.js
@@ -32,6 +32,8 @@ var BrushStroke = function GLBrushStroke() {
     //stroke information
     this._strokeWidth = 0.0;
     this._strokeColor = [0.4, 0.4, 0.4, 1.0];
+    this._secondStrokeColor = this._strokeColor;
+    this._strokeHardness = 100;
     this._strokeMaterial = null;
     this._strokeStyle = "Solid";
 
@@ -114,7 +116,7 @@ var BrushStroke = function GLBrushStroke() {
         //add the point only if it is some epsilon away from the previous point
         var numPoints = this._Points.length;
         if (numPoints>0) {
-            var threshold = this._WETNESS_FACTOR*this._strokeWidth;
+            var threshold = 1;//this._WETNESS_FACTOR*this._strokeWidth;
             var prevPt = this._Points[numPoints-1];
             var diffPt = [prevPt[0]-pt[0], prevPt[1]-pt[1]];
             var diffPtMag = Math.sqrt(diffPt[0]*diffPt[0] + diffPt[1]*diffPt[1]);
@@ -173,6 +175,14 @@ var BrushStroke = function GLBrushStroke() {
         this._strokeColor = c;
     };
 
+    this.setSecondStrokeColor = function(c){
+        this._secondStrokeColor=c;
+    }
+
+    this.setStrokeHardness = function(h){
+        this._strokeHardness=h;
+    }
+
     this.getStrokeStyle = function () {
         return this._strokeStyle;
     };
@@ -219,7 +229,8 @@ var BrushStroke = function GLBrushStroke() {
             var numPoints = this._Points.length;
 
             //**** add samples to the path if needed...linear interpolation for now
-            if (numPoints>1) {
+            //if (numPoints>1) {
+            if (0){
                 var threshold = this._WETNESS_FACTOR*this._strokeWidth;
                 var prevPt = this._Points[0];
                 var prevIndex = 0;
@@ -250,6 +261,44 @@ var BrushStroke = function GLBrushStroke() {
                     }
                 }
             }
+            //**** add samples to the long sections of the path --- Catmull-Rom spline interpolation
+            if (numPoints>1) {
+                var numInsertedPoints = 0;
+                var threshold = 5;//0.25*this._strokeWidth; //this determines whether a segment between two sample is too long
+                var prevPt = this._Points[0];
+                for (var i=1;i<numPoints;i++){
+                    var pt = this._Points[i];
+                    var diff = [pt[0]-prevPt[0], pt[1]-prevPt[1]];
+                    var distance = Math.sqrt(diff[0]*diff[0]+diff[1]*diff[1]);
+                    if (distance>threshold){
+                        //build the control polygon for the Catmull-Rom spline (prev. 2 points and next 2 points)
+                        var prev = (i===1) ? i-1 : i-2;
+                        var next = (i===numPoints-1) ? i : i+1;
+                        var ctrlPts = [this._Points[prev], this._Points[i-1], this._Points[i], this._Points[next]];
+                        //insert points along the prev. to current point
+                        var numNewPoints = Math.floor(distance/threshold);
+                        for (var j=0;j<numNewPoints;j++){
+                            var param = (j+1)/(numNewPoints+1);
+                            var newpt = this._CatmullRomSplineInterpolate(ctrlPts, param);
+                            //insert new point before point i
+                            this._Points.splice(i, 0, newpt);
+                            i++;
+                            numInsertedPoints++;
+                        }
+                        this._dirty=true;
+                    }
+                    prevPt=pt;
+                    //update numPoints to match the new length
+                    numPoints = this._Points.length;
+
+                    //end this function if the numPoints has gone above the max. size specified
+                    if (numPoints> this._MAX_ALLOWED_SAMPLES){
+                        console.log("leaving the resampling because numPoints is greater than limit:"+this._MAX_ALLOWED_SAMPLES);
+                        break;
+                    }
+                }
+                console.log("Inserted "+numInsertedPoints+" additional CatmullRom points");
+            }
 
             // *** compute the bounding box *********
             this._BBoxMin = [Infinity, Infinity, Infinity];
@@ -412,7 +461,7 @@ var BrushStroke = function GLBrushStroke() {
         }
         */
 
-
+        /*
         var R2 = this._strokeWidth;
         var R = R2*0.5;
         var hardness = 0; //for a pencil, this is always 1 //TODO get hardness parameter from user interface
@@ -440,6 +489,109 @@ var BrushStroke = function GLBrushStroke() {
             //ctx.globalCompositeOperation = 'source-in';
             //ctx.rect(x-R, y-R, R2, R2);
         }
+        */
+
+        /*
+        //build the stamp for the brush stroke
+        //todo get this directly from the UI
+        var t=0;
+        var numTraces = this._strokeWidth;
+        var halfNumTraces = numTraces/2;
+        var startPos = [-this._strokeWidth/2,0];
+        var brushStamp = [];
+
+        //build an angled (calligraphic) brush stamp
+        var deltaDisplacement = [1,1];//[this._strokeWidth/numTraces, 0]; //a horizontal line brush
+        for (t=0;t<numTraces;t++){
+            var brushPt = [startPos[0]+t*deltaDisplacement[0], startPos[1]+t*deltaDisplacement[1]];
+            brushStamp.push(brushPt);
+        }
+
+
+        //make a circular brush stamp
+        brushStamp=[];
+        numTraces = this._strokeWidth*Math.PI; //figure out how to
+        var radius = this._strokeWidth/2;
+        for (t=0;t<numTraces;t++)
+        {
+            var angle = Math.PI*(360*t/numTraces)/180;
+            var brushPt = [radius*Math.cos(angle), radius*Math.sin(angle)];
+            brushStamp.push(brushPt);
+        }
+
+//        //make a square brush stamp
+//        STOPPED HERE
+//        brushStamp = [];
+//        numTraces = 4*strokeWidth;
+//        for (t=0;t<numTraces;t++){
+//            if (t<numTraces*0.25){
+//                var brushPt = [startPos[0]+t*deltaDisplacement[0], startPos[1]+t*deltaDisplacement[1]];
+//            } else if (t<numTraces*0.5){
+//
+//            } else if (t<numTraces*0.75){
+//
+//            } else {
+//
+//            }
+//            brushStamp.push(brushPt);
+//        }
+
+        for (t=0;t<numTraces;t++){
+            var disp = [brushStamp[t][0], brushStamp[t][1]];
+            //ctx.globalCompositeOperation = 'source-over';
+            var distFromMiddle = Math.abs(halfNumTraces-t);
+            var alphaVal = 1.0 - (100-this._strokeHardness)*(distFromMiddle/halfNumTraces)/100;
+            alphaVal = 0.2;
+            ctx.save();
+            ctx.lineWidth=this._strokeWidth/10;//todo figure out the correct formula for the line width
+            if (ctx.lineWidth<2)
+                ctx.lineWidth=2;
+            if (t===numTraces-1){
+                ctx.lineWidth = 1;
+            }
+            ctx.lineJoin="bevel";
+            ctx.lineCap="butt";
+            //if (t<numTraces/2)
+                ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
+            //else
+            //    ctx.strokeStyle="rgba("+parseInt(255*this._secondStrokeColor[0])+","+parseInt(255*this._secondStrokeColor[1])+","+parseInt(255*this._secondStrokeColor[2])+","+alphaVal+")";
+            ctx.translate(disp[0],disp[1]);
+            ctx.beginPath();
+            ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
+            for (var i=0;i<numPoints;i++){
+                ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
+            }
+            ctx.stroke();
+            ctx.restore();
+        }
+        */
+
+        /*
+        //debugging path
+        ctx.beginPath();
+        ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
+        for (var i=1;i<numPoints;i++){
+            ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
+        }
+        ctx.lineWidth=1.0;
+        ctx.strokeStyle = "black";
+        ctx.stroke();
+        */
+
+        var numlayers = this._strokeWidth/2;
+        var alphaVal = 1.0/(numlayers-1);
+        for (var l=0;l<numlayers;l++){
+            ctx.beginPath();
+            ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
+            for (var i=1;i<numPoints;i++){
+                ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
+            }
+            ctx.lineCap = "round";
+            ctx.lineJoin="round";
+            ctx.lineWidth=l+1;
+            ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
+            ctx.stroke();
+        }
 
         ctx.restore();
     }; //render()
@@ -473,10 +625,25 @@ var BrushStroke = function GLBrushStroke() {
         return true;
     };
 
-}; //function GLSubpath ...class definition
+}; //function BrushStroke ...class definition
 
 BrushStroke.prototype = new GeomObj();
 
+BrushStroke.prototype._CatmullRomSplineInterpolate = function(ctrlPts, t)
+{
+    //perform CatmullRom interpolation on the spline...assume t is in [0,1]
+    var t2 = t*t;
+    var t3 = t2*t;
+    var retPoint = [0,0,0];
+    for (var i=0;i<3;i++){
+        retPoint[i] = 0.5 *(
+            (2*ctrlPts[1][i]) +
+            (-ctrlPts[0][i] + ctrlPts[2][i]) * t +
+            (2*ctrlPts[0][i] - 5*ctrlPts[1][i] + 4*ctrlPts[2][i] - ctrlPts[3][i]) * t2 +
+            (-ctrlPts[0][i] + 3*ctrlPts[1][i]- 3*ctrlPts[2][i] + ctrlPts[3][i]) * t3);
+    }
+    return retPoint;
+}
 if (typeof exports === "object") {
     exports.BrushStroke = BrushStroke;
-}
\ No newline at end of file
+}
-- 
cgit v1.2.3


From 703fb3d06e88257ac73c1d1a0ec6ca33a64f4371 Mon Sep 17 00:00:00 2001
From: Pushkar Joshi
Date: Wed, 7 Mar 2012 14:33:21 -0800
Subject: implement stroke hardness such that it is percentage of the stroke
 width that's fully the color of the brush

AND
add a smoothing flag for the brush options
---
 js/lib/geom/brush-stroke.js | 66 +++++++++++++--------------------------------
 1 file changed, 19 insertions(+), 47 deletions(-)

(limited to 'js/lib/geom')

diff --git a/js/lib/geom/brush-stroke.js b/js/lib/geom/brush-stroke.js
index 39af5c5c..3e64e730 100755
--- a/js/lib/geom/brush-stroke.js
+++ b/js/lib/geom/brush-stroke.js
@@ -36,6 +36,7 @@ var BrushStroke = function GLBrushStroke() {
     this._strokeHardness = 100;
     this._strokeMaterial = null;
     this._strokeStyle = "Solid";
+    this._strokeDoSmoothing = false;
 
     //the wetness of the brush (currently this is multiplied to the square of the stroke width, but todo should be changed to not depend on stroke width entirely
     //smaller value means more samples for the path
@@ -183,6 +184,10 @@ var BrushStroke = function GLBrushStroke() {
         this._strokeHardness=h;
     }
 
+    this.setDoSmoothing = function(s){
+        this._strokeDoSmoothing = s;
+    }
+
     this.getStrokeStyle = function () {
         return this._strokeStyle;
     };
@@ -262,7 +267,7 @@ var BrushStroke = function GLBrushStroke() {
                 }
             }
             //**** add samples to the long sections of the path --- Catmull-Rom spline interpolation
-            if (numPoints>1) {
+            if (this._strokeDoSmoothing && numPoints>1) {
                 var numInsertedPoints = 0;
                 var threshold = 5;//0.25*this._strokeWidth; //this determines whether a segment between two sample is too long
                 var prevPt = this._Points[0];
@@ -507,35 +512,6 @@ var BrushStroke = function GLBrushStroke() {
             brushStamp.push(brushPt);
         }
 
-
-        //make a circular brush stamp
-        brushStamp=[];
-        numTraces = this._strokeWidth*Math.PI; //figure out how to
-        var radius = this._strokeWidth/2;
-        for (t=0;t<numTraces;t++)
-        {
-            var angle = Math.PI*(360*t/numTraces)/180;
-            var brushPt = [radius*Math.cos(angle), radius*Math.sin(angle)];
-            brushStamp.push(brushPt);
-        }
-
-//        //make a square brush stamp
-//        STOPPED HERE
-//        brushStamp = [];
-//        numTraces = 4*strokeWidth;
-//        for (t=0;t<numTraces;t++){
-//            if (t<numTraces*0.25){
-//                var brushPt = [startPos[0]+t*deltaDisplacement[0], startPos[1]+t*deltaDisplacement[1]];
-//            } else if (t<numTraces*0.5){
-//
-//            } else if (t<numTraces*0.75){
-//
-//            } else {
-//
-//            }
-//            brushStamp.push(brushPt);
-//        }
-
         for (t=0;t<numTraces;t++){
             var disp = [brushStamp[t][0], brushStamp[t][1]];
             //ctx.globalCompositeOperation = 'source-over';
@@ -566,30 +542,26 @@ var BrushStroke = function GLBrushStroke() {
         }
         */
 
-        /*
-        //debugging path
-        ctx.beginPath();
-        ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
-        for (var i=1;i<numPoints;i++){
-            ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
-        }
-        ctx.lineWidth=1.0;
-        ctx.strokeStyle = "black";
-        ctx.stroke();
-        */
 
-        var numlayers = this._strokeWidth/2;
-        var alphaVal = 1.0/(numlayers-1);
+        var minStrokeWidth = (this._strokeHardness*this._strokeWidth)/100; //the hardness is the percentage of the stroke width that's fully opaque
+        var numlayers = 1 + (this._strokeWidth-minStrokeWidth)/2;
+        var alphaVal = 1.0/(numlayers);
+        ctx.lineCap = "round";
+        ctx.lineJoin="round";
+        ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
+        ctx.globalCompositeOperation = 'lighter'; //we wish to add up the colors
+        ctx.globalAlpha = this._strokeColor[3];
         for (var l=0;l<numlayers;l++){
             ctx.beginPath();
             ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
+            if (numPoints===1){
+               ctx.lineTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]+0.01);
+            }
             for (var i=1;i<numPoints;i++){
                 ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
             }
-            ctx.lineCap = "round";
-            ctx.lineJoin="round";
-            ctx.lineWidth=l+1;
-            ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
+
+            ctx.lineWidth=2*l+minStrokeWidth;
             ctx.stroke();
         }
 
-- 
cgit v1.2.3


From fcab2a14f8de302948d38f55db41e2c1c92baa34 Mon Sep 17 00:00:00 2001
From: Pushkar Joshi
Date: Thu, 8 Mar 2012 16:03:17 -0800
Subject: brush stroke options for calligraphic brush style

---
 js/lib/geom/brush-stroke.js | 147 +++++++++++++++++++++++++-------------------
 1 file changed, 84 insertions(+), 63 deletions(-)

(limited to 'js/lib/geom')

diff --git a/js/lib/geom/brush-stroke.js b/js/lib/geom/brush-stroke.js
index 3e64e730..a92657a4 100755
--- a/js/lib/geom/brush-stroke.js
+++ b/js/lib/geom/brush-stroke.js
@@ -37,6 +37,8 @@ var BrushStroke = function GLBrushStroke() {
     this._strokeMaterial = null;
     this._strokeStyle = "Solid";
     this._strokeDoSmoothing = false;
+    this._strokeUseCalligraphic = false;
+    this._strokeAngle = 0;
 
     //the wetness of the brush (currently this is multiplied to the square of the stroke width, but todo should be changed to not depend on stroke width entirely
     //smaller value means more samples for the path
@@ -117,7 +119,7 @@ var BrushStroke = function GLBrushStroke() {
         //add the point only if it is some epsilon away from the previous point
         var numPoints = this._Points.length;
         if (numPoints>0) {
-            var threshold = 1;//this._WETNESS_FACTOR*this._strokeWidth;
+            var threshold = 2;//this._WETNESS_FACTOR*this._strokeWidth;
             var prevPt = this._Points[numPoints-1];
             var diffPt = [prevPt[0]-pt[0], prevPt[1]-pt[1]];
             var diffPtMag = Math.sqrt(diffPt[0]*diffPt[0] + diffPt[1]*diffPt[1]);
@@ -188,6 +190,14 @@ var BrushStroke = function GLBrushStroke() {
         this._strokeDoSmoothing = s;
     }
 
+    this.setStrokeUseCalligraphic = function(c){
+        this._strokeUseCalligraphic = c;
+    }
+
+    this.setStrokeAngle = function(a){
+        this._strokeAngle = a;
+    }
+
     this.getStrokeStyle = function () {
         return this._strokeStyle;
     };
@@ -266,6 +276,8 @@ var BrushStroke = function GLBrushStroke() {
                     }
                 }
             }
+            //todo 4-point subdivision iterations over continuous regions of 'long' segments
+            // look at http://www.gvu.gatech.edu/~jarek/Split&Tweak/ for formula
             //**** add samples to the long sections of the path --- Catmull-Rom spline interpolation
             if (this._strokeDoSmoothing && numPoints>1) {
                 var numInsertedPoints = 0;
@@ -496,75 +508,84 @@ var BrushStroke = function GLBrushStroke() {
         }
         */
 
-        /*
-        //build the stamp for the brush stroke
-        //todo get this directly from the UI
-        var t=0;
-        var numTraces = this._strokeWidth;
-        var halfNumTraces = numTraces/2;
-        var startPos = [-this._strokeWidth/2,0];
-        var brushStamp = [];
-
-        //build an angled (calligraphic) brush stamp
-        var deltaDisplacement = [1,1];//[this._strokeWidth/numTraces, 0]; //a horizontal line brush
-        for (t=0;t<numTraces;t++){
-            var brushPt = [startPos[0]+t*deltaDisplacement[0], startPos[1]+t*deltaDisplacement[1]];
-            brushStamp.push(brushPt);
-        }
 
-        for (t=0;t<numTraces;t++){
-            var disp = [brushStamp[t][0], brushStamp[t][1]];
-            //ctx.globalCompositeOperation = 'source-over';
-            var distFromMiddle = Math.abs(halfNumTraces-t);
-            var alphaVal = 1.0 - (100-this._strokeHardness)*(distFromMiddle/halfNumTraces)/100;
-            alphaVal = 0.2;
-            ctx.save();
-            ctx.lineWidth=this._strokeWidth/10;//todo figure out the correct formula for the line width
-            if (ctx.lineWidth<2)
-                ctx.lineWidth=2;
-            if (t===numTraces-1){
-                ctx.lineWidth = 1;
-            }
-            ctx.lineJoin="bevel";
-            ctx.lineCap="butt";
-            //if (t<numTraces/2)
-                ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
-            //else
-            //    ctx.strokeStyle="rgba("+parseInt(255*this._secondStrokeColor[0])+","+parseInt(255*this._secondStrokeColor[1])+","+parseInt(255*this._secondStrokeColor[2])+","+alphaVal+")";
-            ctx.translate(disp[0],disp[1]);
-            ctx.beginPath();
-            ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
-            for (var i=0;i<numPoints;i++){
-                ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
-            }
-            ctx.stroke();
-            ctx.restore();
-        }
-        */
+        if (this._strokeUseCalligraphic) {
+            //build the stamp for the brush stroke
+            var t=0;
+            var numTraces = this._strokeWidth;
+            var halfNumTraces = numTraces/2;
+            var opaqueRegionHalfWidth = 0.5*this._strokeHardness*numTraces*0.01;
+            var maxTransparentRegionHalfWidth = halfNumTraces-opaqueRegionHalfWidth;
+            var startPos = [-this._strokeWidth/2,0];
+            var brushStamp = [];
 
+            //build an angled (calligraphic) brush stamp
+            var deltaDisplacement = [Math.cos(this._strokeAngle),Math.sin(this._strokeAngle)];
+            deltaDisplacement = VecUtils.vecNormalize(2, deltaDisplacement, 1);
 
-        var minStrokeWidth = (this._strokeHardness*this._strokeWidth)/100; //the hardness is the percentage of the stroke width that's fully opaque
-        var numlayers = 1 + (this._strokeWidth-minStrokeWidth)/2;
-        var alphaVal = 1.0/(numlayers);
-        ctx.lineCap = "round";
-        ctx.lineJoin="round";
-        ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
-        ctx.globalCompositeOperation = 'lighter'; //we wish to add up the colors
-        ctx.globalAlpha = this._strokeColor[3];
-        for (var l=0;l<numlayers;l++){
-            ctx.beginPath();
-            ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
-            if (numPoints===1){
-               ctx.lineTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]+0.01);
+            for (t=0;t<numTraces;t++){
+                var brushPt = [startPos[0]+t*deltaDisplacement[0], startPos[1]+t*deltaDisplacement[1]];
+                brushStamp.push(brushPt);
             }
-            for (var i=1;i<numPoints;i++){
-                ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
+
+            for (t=0;t<numTraces;t++){
+                var disp = [brushStamp[t][0], brushStamp[t][1]];
+                //ctx.globalCompositeOperation = 'source-over';
+                var alphaVal = 1.0;
+                var distFromOpaqueRegion = Math.abs(t-halfNumTraces) - opaqueRegionHalfWidth;
+                if (distFromOpaqueRegion>0) {
+                    alphaVal = 1.0 - distFromOpaqueRegion/maxTransparentRegionHalfWidth;
+                }
+
+                ctx.save();
+                ctx.lineWidth=this._strokeWidth/10;//todo figure out the correct formula for the line width
+                if (ctx.lineWidth<2)
+                    ctx.lineWidth=2;
+                if (t===numTraces-1){
+                    ctx.lineWidth = 1;
+                }
+                ctx.lineJoin="bevel";
+                ctx.lineCap="butt";
+                ctx.globalAlpha = this._strokeColor[3];
+                
+                //if (t<numTraces/2)
+                    ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
+                //else
+                //    ctx.strokeStyle="rgba("+parseInt(255*this._secondStrokeColor[0])+","+parseInt(255*this._secondStrokeColor[1])+","+parseInt(255*this._secondStrokeColor[2])+","+alphaVal+")";
+                ctx.translate(disp[0],disp[1]);
+                ctx.beginPath();
+                ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
+                for (var i=0;i<numPoints;i++){
+                    ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
+                }
+                ctx.stroke();
+                ctx.restore();
             }
+        } else {
 
-            ctx.lineWidth=2*l+minStrokeWidth;
-            ctx.stroke();
+            ctx.globalCompositeOperation = 'lighter'; //we wish to add up the colors
+            ctx.globalAlpha = this._strokeColor[3];
+            ctx.lineCap = "round";
+            ctx.lineJoin="round";
+            var minStrokeWidth = (this._strokeHardness*this._strokeWidth)/100; //the hardness is the percentage of the stroke width that's fully opaque
+            var numlayers = 1 + (this._strokeWidth-minStrokeWidth)/2;
+            var alphaVal = 1.0/(numlayers); //this way the alpha at the first path will be 1
+            ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
+            for (var l=0;l<numlayers;l++){
+                ctx.beginPath();
+                ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
+                if (numPoints===1){
+                    //display a tiny segment as a single point
+                   ctx.lineTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]+0.01);
+                }
+                for (var i=1;i<numPoints;i++){
+                    ctx.lineTo(this._Points[i][0]-bboxMin[0], this._Points[i][1]-bboxMin[1]);
+                }
+                ctx.lineWidth=2*l+minStrokeWidth;
+                ctx.stroke();
+            }
         }
-
+        
         ctx.restore();
     }; //render()
 
-- 
cgit v1.2.3


From 00b1e6a9bed04172ad84bdd810f1bd999e8fa0eb Mon Sep 17 00:00:00 2001
From: Pushkar Joshi
Date: Mon, 12 Mar 2012 15:02:07 -0700
Subject: bug fixes for spline interpolation

AND
Laplacian smoothing for denoising
AND
code cleanup (removing blocks of commented code)
---
 js/lib/geom/brush-stroke.js | 245 +++++++++++++++-----------------------------
 1 file changed, 81 insertions(+), 164 deletions(-)

(limited to 'js/lib/geom')

diff --git a/js/lib/geom/brush-stroke.js b/js/lib/geom/brush-stroke.js
index a92657a4..595a6a63 100755
--- a/js/lib/geom/brush-stroke.js
+++ b/js/lib/geom/brush-stroke.js
@@ -32,7 +32,7 @@ var BrushStroke = function GLBrushStroke() {
     //stroke information
     this._strokeWidth = 0.0;
     this._strokeColor = [0.4, 0.4, 0.4, 1.0];
-    this._secondStrokeColor = this._strokeColor;
+    this._secondStrokeColor = [1, 0.4, 0.4, 1.0];
     this._strokeHardness = 100;
     this._strokeMaterial = null;
     this._strokeStyle = "Solid";
@@ -44,6 +44,12 @@ var BrushStroke = function GLBrushStroke() {
     //smaller value means more samples for the path
     this._WETNESS_FACTOR = 0.25;
 
+    //threshold that tells us whether two samples are too far apart
+    this._MAX_SAMPLE_DISTANCE_THRESHOLD = 5;
+
+    //threshold that tells us whether two samples are too close
+    this._MIN_SAMPLE_DISTANCE_THRESHOLD = 2;
+
     //prevent extremely long paths that can take a long time to render
     this._MAX_ALLOWED_SAMPLES = 500;
 
@@ -119,7 +125,7 @@ var BrushStroke = function GLBrushStroke() {
         //add the point only if it is some epsilon away from the previous point
         var numPoints = this._Points.length;
         if (numPoints>0) {
-            var threshold = 2;//this._WETNESS_FACTOR*this._strokeWidth;
+            var threshold = this._MIN_SAMPLE_DISTANCE_THRESHOLD;//this._WETNESS_FACTOR*this._strokeWidth;
             var prevPt = this._Points[numPoints-1];
             var diffPt = [prevPt[0]-pt[0], prevPt[1]-pt[1]];
             var diffPtMag = Math.sqrt(diffPt[0]*diffPt[0] + diffPt[1]*diffPt[1]);
@@ -276,13 +282,16 @@ var BrushStroke = function GLBrushStroke() {
                     }
                 }
             }
+
             //todo 4-point subdivision iterations over continuous regions of 'long' segments
             // look at http://www.gvu.gatech.edu/~jarek/Split&Tweak/ for formula
             //**** add samples to the long sections of the path --- Catmull-Rom spline interpolation
             if (this._strokeDoSmoothing && numPoints>1) {
                 var numInsertedPoints = 0;
-                var threshold = 5;//0.25*this._strokeWidth; //this determines whether a segment between two sample is too long
+                var newPoints = [];
+                var threshold = this._MAX_SAMPLE_DISTANCE_THRESHOLD;//this determines whether a segment between two sample is long enough to warrant checking for angle
                 var prevPt = this._Points[0];
+                newPoints.push(this._Points[0]);
                 for (var i=1;i<numPoints;i++){
                     var pt = this._Points[i];
                     var diff = [pt[0]-prevPt[0], pt[1]-prevPt[1]];
@@ -298,12 +307,14 @@ var BrushStroke = function GLBrushStroke() {
                             var param = (j+1)/(numNewPoints+1);
                             var newpt = this._CatmullRomSplineInterpolate(ctrlPts, param);
                             //insert new point before point i
-                            this._Points.splice(i, 0, newpt);
-                            i++;
+                            //this._Points.splice(i, 0, newpt);
+                            //i++;
+                            newPoints.push(newpt);
                             numInsertedPoints++;
                         }
                         this._dirty=true;
                     }
+                    newPoints.push(pt);
                     prevPt=pt;
                     //update numPoints to match the new length
                     numPoints = this._Points.length;
@@ -314,7 +325,22 @@ var BrushStroke = function GLBrushStroke() {
                         break;
                     }
                 }
+                this._Points = newPoints;
+                numPoints = this._Points.length;
                 console.log("Inserted "+numInsertedPoints+" additional CatmullRom points");
+
+                //now do 3-4 iterations of Laplacian smoothing (setting the points to the average of their neighbors)
+                var numLaplacianIterations = 3; //todo figure out the proper number of Laplacian iterations (perhaps as a function of stroke width)
+                for (var n=0;n<numLaplacianIterations;n++){
+                    newPoints = this._Points;
+                    for (var i=1;i<numPoints-1;i++){
+                        var avgPos = [  0.5*(this._Points[i-1][0] + this._Points[i+1][0]),
+                                        0.5*(this._Points[i-1][1] + this._Points[i+1][1]),
+                                        0.5*(this._Points[i-1][2] + this._Points[i+1][2])] ;
+                        newPoints[i] = avgPos;
+                    }
+                    this._Points = newPoints;
+                }
             }
 
             // *** compute the bounding box *********
@@ -337,11 +363,20 @@ var BrushStroke = function GLBrushStroke() {
                     }//for every dimension d from 0 to 2
                 }
             }
-             //increase the bbox given the stroke width
-            for (var d = 0; d < 3; d++) {
-                this._BBoxMin[d]-= this._strokeWidth/2;
-                this._BBoxMax[d]+= this._strokeWidth/2;
-            }//for every dimension d from 0 to 2
+
+            //increase the bbox given the stroke width and the angle (in case of calligraphic brush)
+            var bboxPadding = this._strokeWidth/2;
+            if (this.__strokeUseCalligraphic) {
+                this._BBoxMin[0]-= bboxPadding*Math.cos(this._strokeAngle);
+                this._BBoxMin[1]-= bboxPadding*Math.sin(this._strokeAngle);
+                this._BBoxMax[0]+= bboxPadding*Math.cos(this._strokeAngle);
+                this._BBoxMax[1]+= bboxPadding*Math.sin(this._strokeAngle);
+            } else {
+                for (var d = 0; d < 3; d++) {
+                    this._BBoxMin[d]-= bboxPadding;
+                    this._BBoxMax[d]+= bboxPadding;
+                }//for every dimension d from 0 to 2
+            }
         }
         this._dirty = false;
     };
@@ -375,183 +410,66 @@ var BrushStroke = function GLBrushStroke() {
         var bboxHeight = bboxMax[1] - bboxMin[1];
         ctx.clearRect(0, 0, bboxWidth, bboxHeight);
 
-        /*
-        ctx.lineWidth = this._strokeWidth;
-        ctx.strokeStyle = "black";
-        if (this._strokeColor)
-            ctx.strokeStyle = MathUtils.colorToHex( this._strokeColor );
-        ctx.fillStyle = "blue";
-        if (this._fillColor)
-            ctx.fillStyle = MathUtils.colorToHex( this._fillColor );
-        var lineCap = ['butt','round','square'];
-        ctx.lineCap = lineCap[1];
-        ctx.beginPath();
-        var firstPoint = this._Points[0];
-        ctx.moveTo(firstPoint[0]-bboxMin[0], firstPoint[1]-bboxMin[1]);
-        for (var i = 1; i < numPoints; i++) {
-            var pt = this._Points[i];
-            ctx.lineTo(pt[0]-bboxMin[0], pt[1]-bboxMin[1]);
-        }
-        ctx.stroke();
-        */
-
-        /*
-        var isDebug = false;
-        var prevPt = this._Points[0];
-        var prevX = prevPt[0]-bboxMin[0];
-        var prevY = prevPt[1]-bboxMin[1];
-        prevPt = [prevX,prevY];
-        for (var i = 1; i < numPoints; i++) {
-            var pt = this._Points[i];
-            ctx.globalCompositeOperation = 'source-over';
-            var x = pt[0]-bboxMin[0];
-            var y = pt[1]-bboxMin[1];
-            pt = [x,y];
-
-            //vector from prev to current pt
-            var seg = VecUtils.vecSubtract(2, pt, prevPt);
-            var segDir = VecUtils.vecNormalize(2, seg, 1.0);
-
-            var segMidPt = VecUtils.vecInterpolate(2, pt, prevPt, 0.5);
-            var w2 = this._strokeWidth*0.5;
-            var segDirOrtho = [w2*segDir[1], -w2*segDir[0]];
-            
-            //add half the strokewidth to the segMidPt
-            var lgStart = VecUtils.vecAdd(2, segMidPt, segDirOrtho);
-            var lgEnd = VecUtils.vecSubtract(2, segMidPt, segDirOrtho);
-
-            ctx.save();
-            ctx.beginPath();
-
-            if (isDebug) {
-                ctx.strokeStyle="black";
-                ctx.lineWidth = 1;
-
-                ctx.moveTo(lgStart[0], lgStart[1]);
-                ctx.lineTo(lgEnd[0], lgEnd[1]);
-                ctx.stroke();
-            }
-
-            var lg = ctx.createLinearGradient(lgStart[0], lgStart[1], lgEnd[0], lgEnd[1]);
-            lg.addColorStop(1, 'rgba(0,0,0,0.0)');
-            lg.addColorStop(0.5,'rgba(255,0,0,1.0)');
-            lg.addColorStop(0, 'rgba(0,0,0,0.0)');
-            ctx.fillStyle = lg;
-
-            if (isDebug){
-                ctx.strokeStyle="blue";
-                ctx.lineWidth=0.5;
-            }
-            ctx.moveTo(prevX-w2, prevY);
-            ctx.lineTo(prevX+w2, prevY);
-            ctx.lineTo(x+w2, y);
-            ctx.lineTo(x-w2, y);
-            ctx.lineTo(prevX-w2, prevY);
-            ctx.fill();
-            ctx.closePath();
-
-            ctx.restore();
-
-            prevPt = pt;
-            prevX = x;
-            prevY = y;
-        }
-        
-
-        if (isDebug)
-            ctx.stroke();
-
-        if (isDebug){
-            //draw the skeleton of this stroke
-            ctx.lineWidth = 1;
-            ctx.strokeStyle = "black";
-            var pt = this._Points[0];
-            ctx.beginPath();
-            ctx.moveTo(pt[0]-bboxMin[0],pt[1]-bboxMin[1]);
-            for (var i = 1; i < numPoints; i++) {
-                pt = this._Points[i];
-                var x = pt[0]-bboxMin[0];
-                var y = pt[1]-bboxMin[1];
-                ctx.lineTo(x,y);
-            }
-            ctx.stroke();
-        }
-        */
-
-        /*
-        var R2 = this._strokeWidth;
-        var R = R2*0.5;
-        var hardness = 0; //for a pencil, this is always 1 //TODO get hardness parameter from user interface
-        var innerRadius = (hardness*R)-1;
-        if (innerRadius<1)
-            innerRadius=1;
-
-        var r = ctx.createRadialGradient(0,0,innerRadius, 0,0,R);
-        var midColor = "rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+",1)";
-        r.addColorStop(0, midColor);
-        var endColor = "rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+",0.0)";
-        r.addColorStop(1, endColor);
-        ctx.fillStyle = r;
-
-        for (var i = 0; i < numPoints; i++) {
-            var pt = this._Points[i];
-            ctx.globalCompositeOperation = 'source-over';
-            var x = pt[0]-bboxMin[0];
-            var y = pt[1]-bboxMin[1];
-            ctx.save();
-            ctx.translate(x,y);
-            ctx.arc(0, 0, R, 0, 2 * Math.PI, false);
-            ctx.fill();
-            ctx.restore();
-            //ctx.globalCompositeOperation = 'source-in';
-            //ctx.rect(x-R, y-R, R2, R2);
-        }
-        */
-
-
         if (this._strokeUseCalligraphic) {
             //build the stamp for the brush stroke
             var t=0;
             var numTraces = this._strokeWidth;
             var halfNumTraces = numTraces/2;
-            var opaqueRegionHalfWidth = 0.5*this._strokeHardness*numTraces*0.01;
+            var opaqueRegionHalfWidth = 0.5*this._strokeHardness*numTraces*0.01; //the 0.01 is to convert the strokeHardness from [0,100] to [0,1]
             var maxTransparentRegionHalfWidth = halfNumTraces-opaqueRegionHalfWidth;
-            var startPos = [-this._strokeWidth/2,0];
-            var brushStamp = [];
 
             //build an angled (calligraphic) brush stamp
             var deltaDisplacement = [Math.cos(this._strokeAngle),Math.sin(this._strokeAngle)];
             deltaDisplacement = VecUtils.vecNormalize(2, deltaDisplacement, 1);
+            var startPos = [-halfNumTraces*deltaDisplacement[0],-halfNumTraces*deltaDisplacement[1]];
 
-            for (t=0;t<numTraces;t++){
+            var brushStamp = [];
+            /*for (t=0;t<numTraces;t++){
                 var brushPt = [startPos[0]+t*deltaDisplacement[0], startPos[1]+t*deltaDisplacement[1]];
                 brushStamp.push(brushPt);
+            }*/
+            //todo BEGIN TEMP
+            numTraces *=2;
+            halfNumTraces *= 2;
+            opaqueRegionHalfWidth *=2;
+            maxTransparentRegionHalfWidth *= 2;
+            for (t=0;t<numTraces;t++){
+                var brushPt = [startPos[0]+t*deltaDisplacement[0]*0.5, startPos[1]+t*deltaDisplacement[1]*0.5];
+                brushStamp.push(brushPt);
             }
+            //todo END TEMP
+
+            ctx.lineJoin="bevel";
+            ctx.lineCap="butt";
+            ctx.globalCompositeOperation = 'source-over';
+            //if (maxTransparentRegionHalfWidth===0){
+                ctx.globalCompositeOperation ='lighter'; //todo...we wish to add up the colors, but 'lighter' seems to produce white pixels unlike the round brush
+            //}
+            ctx.globalAlpha = this._strokeColor[3];
+            ctx.lineWidth=this._strokeWidth/10;//todo figure out the correct formula for the line width
+            //if (ctx.lineWidth<2)
+                ctx.lineWidth=1;
+            //if (t===numTraces-1){
+            //    ctx.lineWidth = 1;
+            //}
 
             for (t=0;t<numTraces;t++){
                 var disp = [brushStamp[t][0], brushStamp[t][1]];
-                //ctx.globalCompositeOperation = 'source-over';
                 var alphaVal = 1.0;
                 var distFromOpaqueRegion = Math.abs(t-halfNumTraces) - opaqueRegionHalfWidth;
                 if (distFromOpaqueRegion>0) {
                     alphaVal = 1.0 - distFromOpaqueRegion/maxTransparentRegionHalfWidth;
+                    alphaVal *= 1.0/ctx.lineWidth; //factor that accounts for lineWidth !== 1
                 }
 
                 ctx.save();
-                ctx.lineWidth=this._strokeWidth/10;//todo figure out the correct formula for the line width
-                if (ctx.lineWidth<2)
-                    ctx.lineWidth=2;
-                if (t===numTraces-1){
-                    ctx.lineWidth = 1;
-                }
-                ctx.lineJoin="bevel";
-                ctx.lineCap="butt";
-                ctx.globalAlpha = this._strokeColor[3];
-                
-                //if (t<numTraces/2)
-                    ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
-                //else
-                //    ctx.strokeStyle="rgba("+parseInt(255*this._secondStrokeColor[0])+","+parseInt(255*this._secondStrokeColor[1])+","+parseInt(255*this._secondStrokeColor[2])+","+alphaVal+")";
+
+                ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
+                //linearly interpolate between the two stroke colors
+                var currStrokeColor = VecUtils.vecInterpolate(4, this._strokeColor, this._secondStrokeColor, t/numTraces);
+                //ctx.globalAlpha = currStrokeColor[3];
+                //ctx.strokeStyle="rgba("+parseInt(255*currStrokeColor[0])+","+parseInt(255*currStrokeColor[1])+","+parseInt(255*currStrokeColor[2])+","+alphaVal+")";
+
                 ctx.translate(disp[0],disp[1]);
                 ctx.beginPath();
                 ctx.moveTo(this._Points[0][0]-bboxMin[0], this._Points[0][1]-bboxMin[1]);
@@ -562,7 +480,6 @@ var BrushStroke = function GLBrushStroke() {
                 ctx.restore();
             }
         } else {
-
             ctx.globalCompositeOperation = 'lighter'; //we wish to add up the colors
             ctx.globalAlpha = this._strokeColor[3];
             ctx.lineCap = "round";
-- 
cgit v1.2.3


From 7b4b068cadc0af8ec7e930e1c2b429e945f96984 Mon Sep 17 00:00:00 2001
From: Pushkar Joshi
Date: Mon, 12 Mar 2012 15:21:59 -0700
Subject: seemingly working version of the calligraphic brush (seems to work
 with transparency and large stroke widths...seems to work better with
 smoothing)

---
 js/lib/geom/brush-stroke.js | 26 ++++++--------------------
 1 file changed, 6 insertions(+), 20 deletions(-)

(limited to 'js/lib/geom')

diff --git a/js/lib/geom/brush-stroke.js b/js/lib/geom/brush-stroke.js
index 595a6a63..4c42539a 100755
--- a/js/lib/geom/brush-stroke.js
+++ b/js/lib/geom/brush-stroke.js
@@ -424,34 +424,21 @@ var BrushStroke = function GLBrushStroke() {
             var startPos = [-halfNumTraces*deltaDisplacement[0],-halfNumTraces*deltaDisplacement[1]];
 
             var brushStamp = [];
-            /*for (t=0;t<numTraces;t++){
-                var brushPt = [startPos[0]+t*deltaDisplacement[0], startPos[1]+t*deltaDisplacement[1]];
-                brushStamp.push(brushPt);
-            }*/
-            //todo BEGIN TEMP
-            numTraces *=2;
-            halfNumTraces *= 2;
-            opaqueRegionHalfWidth *=2;
-            maxTransparentRegionHalfWidth *= 2;
             for (t=0;t<numTraces;t++){
-                var brushPt = [startPos[0]+t*deltaDisplacement[0]*0.5, startPos[1]+t*deltaDisplacement[1]*0.5];
+                var brushPt = [startPos[0]+t*deltaDisplacement[0], startPos[1]+t*deltaDisplacement[1]];
                 brushStamp.push(brushPt);
             }
-            //todo END TEMP
 
             ctx.lineJoin="bevel";
             ctx.lineCap="butt";
             ctx.globalCompositeOperation = 'source-over';
-            //if (maxTransparentRegionHalfWidth===0){
-                ctx.globalCompositeOperation ='lighter'; //todo...we wish to add up the colors, but 'lighter' seems to produce white pixels unlike the round brush
-            //}
             ctx.globalAlpha = this._strokeColor[3];
-            ctx.lineWidth=this._strokeWidth/10;//todo figure out the correct formula for the line width
+            //ctx.lineWidth=this._strokeWidth/10;//todo figure out the correct formula for the line width
             //if (ctx.lineWidth<2)
-                ctx.lineWidth=1;
-            //if (t===numTraces-1){
-            //    ctx.lineWidth = 1;
-            //}
+            ctx.lineWidth=2;
+            if (t===numTraces-1){
+                ctx.lineWidth = 1;
+            }
 
             for (t=0;t<numTraces;t++){
                 var disp = [brushStamp[t][0], brushStamp[t][1]];
@@ -467,7 +454,6 @@ var BrushStroke = function GLBrushStroke() {
                 ctx.strokeStyle="rgba("+parseInt(255*this._strokeColor[0])+","+parseInt(255*this._strokeColor[1])+","+parseInt(255*this._strokeColor[2])+","+alphaVal+")";
                 //linearly interpolate between the two stroke colors
                 var currStrokeColor = VecUtils.vecInterpolate(4, this._strokeColor, this._secondStrokeColor, t/numTraces);
-                //ctx.globalAlpha = currStrokeColor[3];
                 //ctx.strokeStyle="rgba("+parseInt(255*currStrokeColor[0])+","+parseInt(255*currStrokeColor[1])+","+parseInt(255*currStrokeColor[2])+","+alphaVal+")";
 
                 ctx.translate(disp[0],disp[1]);
-- 
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