removed instability

index.html

@@ -174,6 +174,9 @@
                 vec4 thetas = texture2D(u_theta, scaledCreaseIndex);
                 vec3 creaseMeta = texture2D(u_creaseMeta, scaledCreaseIndex).xyz;//[k, d, targetTheta]
 
+                float targetTheta = creaseMeta[2] * u_creasePercent;
+                float angForce = creaseMeta[0]*(targetTheta-thetas[0]);// + creaseMeta[1]*thetas[1];
+
                 if (creaseMeta2[3] < 0.0){//crease reaction
                     float nodeNum = creaseMeta2[2];
 
@@ -189,16 +192,14 @@
                     scaledNormalsIndex = normalsIndex/u_textureDimFaces;
                     vec3 normal2 = texture2D(u_normals, scaledNormalsIndex).xyz;
 
-                    float targetTheta = creaseMeta[2] * u_creasePercent;
-
-                    float angForce = creaseMeta[0]*(targetTheta-thetas[0]);// + creaseMeta[1]*thetas[1];
+                    float momentArm1 = creaseMeta2[1];
+                    float momentArm2 = creaseMeta2[2];
 
-                    vec3 _force = -0.5*(angForce/creaseMeta2[1]*normal1 + angForce/creaseMeta2[2]*normal2);
+                    vec3 _force = -0.5*(angForce/momentArm1*normal1 + angForce/momentArm2*normal2);
                     force += _force;
                 } else {
                     float nodeNum = creaseMeta2[2];
                     float normalIndex1D = thetas[2];//node #1
-                    float targetTheta = creaseMeta[2] * u_creasePercent;
                     if (nodeNum > 1.1) {
                         normalIndex1D = thetas[3];//node #2
                     }
@@ -206,7 +207,6 @@
                     vec2 scaledNormalsIndex = normalsIndex/u_textureDimFaces;
                     vec3 normal = texture2D(u_normals, scaledNormalsIndex).xyz;
 
-                    float angForce = creaseMeta[0]*(targetTheta-thetas[0]);// + creaseMeta[1]*thetas[1];
                     float momentArm = creaseMeta2[1];
 
                     vec3 _force = angForce/momentArm*normal;
@@ -221,7 +221,7 @@
     </script>
 
     <script id="thetaCalcShader" type="x-shader/x-fragment">
-        #define M_PI 3.1415926535897932384626433832795
+        #define TWO_PI 6.283185307179586476925286766559
         precision mediump float;
         uniform vec2 u_textureDimFaces;
         uniform vec2 u_textureDimCreases;
@@ -249,12 +249,15 @@
             vec3 normal1 = texture2D(u_normals, normal1Index).xyz;
             vec3 normal2 = texture2D(u_normals, normal2Index).xyz;
 
-            float theta = acos(dot(normal1, normal2));//normals are already normalized, no need to divide by length
+            float dotNormals = dot(normal1, normal2);//normals are already normalized, no need to divide by length
+            //if (dotNormals < -0.999) dotNormals = -0.999;
+            //else if (dotNormals > 0.999) dotNormals = 0.999;
+            float theta = acos(dotNormals);
             vec3 creaseVector = texture2D(u_creaseVectors, scaledFragCoord).xyz;
             float sign = dot(cross(normal1, normal2), creaseVector);
             if (sign < 0.0) theta *= -1.0;
-            if (theta > 3.0 && lastTheta[0] < -3.0) theta -= 2.0*M_PI*(1.0+floor(lastTheta[0]/2.0*M_PI));
-            if (theta < -3.0 && lastTheta[0] > 3.0) theta += 2.0*M_PI*(1.0+floor(lastTheta[0]/2.0*M_PI));
+            if (theta > 2.0 && lastTheta[0] < -2.0) theta -= TWO_PI*(1.0+floor(-lastTheta[0]/TWO_PI));
+            if (theta < -2.0 && lastTheta[0] > 2.0) theta += TWO_PI*(1.0+floor(lastTheta[0]/TWO_PI));
             gl_FragColor = vec4(theta, theta-lastTheta[0], lastTheta[2], lastTheta[3]);//[theta, w, normal1Index, normal2Index]
         }
     </script>

js/crease.js

@@ -68,7 +68,12 @@ Crease.prototype.getLengthTo = function(node){
     var nodePosition = node.getOriginalPosition();
     var vector2 = nodePosition.sub(this.edge.nodes[1].getOriginalPosition());
     var projLength = vector1.dot(vector2);
-    return Math.sqrt(vector2.lengthSq()-projLength*projLength);
+    var length = Math.sqrt(vector2.lengthSq()-projLength*projLength);
+    if (length <= 0.0) {
+        console.warn("bad moment arm");
+        length = 0.001;
+    }
+    return length;
 };
 
 Crease.prototype.getNodeIndex = function(node){

js/dynamicModel.js

@@ -202,7 +202,7 @@ function initDynamicModel(globals){
             console.log("here");
         }
 
-        globals.gpuMath.setSize(textureDim, textureDim);
+        //globals.gpuMath.setSize(textureDim, textureDim);
     }
 
     function setSolveParams(){

js/model.js

@@ -46,7 +46,7 @@ function initModel(globals){
         }
 
         var _creases = [];
-        for (var i=0;i<1;i++) {//allCreaseParams.length
+        for (var i=0;i<allCreaseParams.length;i++) {//allCreaseParams.length
             var creaseParams = allCreaseParams[i];//face1Ind, vertInd, face2Ind, ver2Ind, edgeInd, angle
             _edges[creaseParams[4]].highlight();
             _creases.push(new Crease(_edges[creaseParams[4]], creaseParams[0], creaseParams[2], creaseParams[5], 1, _nodes[creaseParams[1]], _nodes[creaseParams[3]], _creases.length));