Using single hover render for active nodes

Redrawing just the actives (eg selection neighbors) is possible in the canvas context of hover layer and is 140 x faster than full redraw

tinawebJS/main.js

@@ -262,8 +262,14 @@ if(RES["OK"]) {
 
     // custom labels rendering
     //  - based on the normal one sigma.canvas.labels.def
-    //  - additionnaly supports 'forcelabel' node property
-    sigma.canvas.labels.def = sigma_utils.twRender.canvas.labels.def
+    //  - additionnaly supports 'active/forcelabel' node property (magnify x 3)
+    sigma.canvas.labels.def = sigma_utils.twRender.canvas.labels.largeractive
+
+    // custom hovers rendering
+    //  - based on the normal one sigma.canvas.hovers.def
+    //  - additionnaly magnifies all labels x 2
+    //  - additionnaly supports 'active/forcelabel' node property (magnify x 3)
+    sigma.canvas.hovers.def = sigma_utils.twRender.canvas.hovers.largerall
 
 
     // ==================================================================

tinawebJS/methods.js

@@ -205,25 +205,68 @@ function htmlfied_alternodes(elems) {
     return oppositesNodes
 }
 
-function manualForceLabel(nodeid,active) {
+function manualForceLabel(nodeid, active, justHover) {
 	// console.log("manual|"+nodeid+"|"+active)
-	TW.partialGraph.graph.nodes(nodeid).active=active;
+  var nd = TW.partialGraph.graph.nodes(nodeid)
+	nd.active=active;
+
+  // console.log('justHover', justHover)
+  // var t0, t1
+
+  if (justHover) {
+    // using single node redraw in hover layer (much faster ~ 0.5ms)
+    redrawNodesInHoverLayer([nd])
+  }
+  else {
+    // using full redraw in permanent layers (slow ~ 70ms)
+    TW.partialGraph.render();
+  }
+}
+
+// Here we draw within hover layer instead of nodes layer, labels layer
+//
+// Explanation: it's perfect for temporary change cases because hover layer
+//              is *over* all other layers and contains nothing by default
+//              (this way step A can reset B avoiding whole graph refresh)
+function redrawNodesInHoverLayer(someNodes) {
+  var targetLayer = TW.rend.contexts.hover
+
+  // A - clear entire targetLayer
+  targetLayer.clearRect(
+    0, 0,
+    targetLayer.canvas.width,
+    targetLayer.canvas.height
+  )
+
+  var locSettings = TW.partialGraph.settings.embedObjects({prefix:'renderer1:'})
+
+  for (var k in someNodes) {
+    // B - we use our largerall renderer to write single nodes to overlay
+    sigma.canvas.hovers.def( someNodes[k], targetLayer, locSettings)
+  }
+}
+
 
-  // full redraw
-  // TODO try single node redraw
-  TW.partialGraph.render();
+function clearHover() {
+  var hoverLayer = TW.rend.contexts.hover
+  hoverLayer.clearRect(
+    0, 0,
+    hoverLayer.canvas.width,
+    hoverLayer.canvas.height
+  )
 }
 
+
 function htmlfied_samenodes(elems) {
     var sameNodes=[]
-    js1=' onmouseover="manualForceLabel(this.id,true);" ';
-    js2=' onmouseout="manualForceLabel(this.id,true);" ';
+    js1=' onmouseover="manualForceLabel(this.id,true, true);" ';
+    js2=' onmouseout="manualForceLabel(this.id,true, true);" ';
     if(elems.length>0) {
         var A = getVisibleNodes()
         for (var a in A){
             n = A[a]
             if(!n.active && n.color.charAt(0)=="#" ) {
-                sameNodes.push('<li onmouseover="manualForceLabel(\''+n.id+'\',true)"  onmouseout="manualForceLabel(\''+n.id+'\',false)" ><a>'+ n.label+ '</a></li>')
+                sameNodes.push('<li onmouseover="manualForceLabel(\''+n.id+'\',true, true)"  onmouseout="manualForceLabel(\''+n.id+'\',false, true)" ><a>'+ n.label+ '</a></li>')
             }
         }
     }
@@ -306,7 +349,7 @@ function htmlfied_tagcloud(elems , limit) {
         if(!isUndef(TW.Nodes[id])){
             //          js1            js2
             // onclick="graphTagCloudElem('  ');
-            var jspart = ' onclick="manualSelectNode(\''+id+'\')" onmouseover="manualForceLabel(\''+id+'\',true)"  onmouseout="manualForceLabel(\''+id+'\',false)"'
+            var jspart = ' onclick="manualSelectNode(\''+id+'\')" onmouseover="manualForceLabel(\''+id+'\',true, true)"  onmouseout="manualForceLabel(\''+id+'\',false, true)"'
             htmlfied_alternode = '<span class="tagcloud-item" style="font-size:'+fontSize+'px;" '+jspart+'>'+ TW.Nodes[id].label+ '</span>';
             oppositesNodes.push(htmlfied_alternode)
         }

tinawebJS/sigmaUtils.js

@@ -92,9 +92,9 @@ SigmaUtils = function () {
     // cf. http://yomguithereal.github.io/articles/node-border-renderer/
 
     // same hierarchy as in sigma.canvas
-    this.twRender = {canvas: {nodes: {}, edges: {}, labels: {}}}
+    this.twRender = {canvas: {nodes: {}, edges: {}, labels: {}, hovers: {}}}
 
-    this.twRender.canvas.labels.def = function(node, context, settings) {
+    this.twRender.canvas.labels.largeractive = function(node, context, settings) {
       var fontSize,
           prefix = settings('prefix') || '',
           size = node[prefix + 'size'];
@@ -112,7 +112,7 @@ SigmaUtils = function () {
         settings('defaultLabelSize') :
         settings('labelSizeRatio') * size;
 
-      // we also boost size of active nodes
+      // our only customization: we boost size of active nodes
       if (activeFlag)  fontSize *= 3
 
 
@@ -200,6 +200,106 @@ SigmaUtils = function () {
         );
         context.closePath();
         context.fill();
+    };
+
+
+    // hover rendering with size boost
+    this.twRender.canvas.hovers.largerall = function(node, context, settings) {
+        var x,
+            y,
+            w,
+            h,
+            e,
+            fontStyle = settings('hoverFontStyle') || settings('fontStyle'),
+            prefix = settings('prefix') || '',
+            size = node[prefix + 'size'],
+            fontSize = (settings('labelSize') === 'fixed') ?
+              settings('defaultLabelSize') :
+              settings('labelSizeRatio') * size;
+
+        // largerall: our customized size boosts
+        if (node.active || node.forceLabel) {
+          fontSize *= 3
+        }
+        else {
+          fontSize *= 2
+        }
+
+        // Label background:
+        context.font = (fontStyle ? fontStyle + ' ' : '') +
+          fontSize + 'px ' + (settings('hoverFont') || settings('font'));
+
+        context.beginPath();
+        context.fillStyle = settings('labelHoverBGColor') === 'node' ?
+          (node.color || settings('defaultNodeColor')) :
+          settings('defaultHoverLabelBGColor');
+
+        if (node.label && settings('labelHoverShadow')) {
+          context.shadowOffsetX = 0;
+          context.shadowOffsetY = 0;
+          context.shadowBlur = 8;
+          context.shadowColor = settings('labelHoverShadowColor');
+        }
+
+        if (node.label && typeof node.label === 'string') {
+          x = Math.round(node[prefix + 'x'] - fontSize / 2 - 2);
+          y = Math.round(node[prefix + 'y'] - fontSize / 2 - 2);
+          w = Math.round(
+            context.measureText(node.label).width + fontSize / 2 + size + 7
+          );
+          h = Math.round(fontSize + 4);
+          e = Math.round(fontSize / 2 + 2);
+
+          context.moveTo(x, y + e);
+          context.arcTo(x, y, x + e, y, e);
+          context.lineTo(x + w, y);
+          context.lineTo(x + w, y + h);
+          context.lineTo(x + e, y + h);
+          context.arcTo(x, y + h, x, y + h - e, e);
+          context.lineTo(x, y + e);
+
+          context.closePath();
+          context.fill();
+
+          context.shadowOffsetX = 0;
+          context.shadowOffsetY = 0;
+          context.shadowBlur = 0;
+        }
+
+        // Node border:
+        if (settings('borderSize') > 0) {
+          context.beginPath();
+          context.fillStyle = settings('nodeBorderColor') === 'node' ?
+            (node.color || settings('defaultNodeColor')) :
+            settings('defaultNodeBorderColor');
+          context.arc(
+            node[prefix + 'x'],
+            node[prefix + 'y'],
+            size + settings('borderSize'),
+            0,
+            Math.PI * 2,
+            true
+          );
+          context.closePath();
+          context.fill();
+        }
+
+        // Node:
+        var nodeRenderer = sigma.canvas.nodes[node.type] || sigma.canvas.nodes.def;
+        nodeRenderer(node, context, settings);
+
+        // Display the label:
+        if (node.label && typeof node.label === 'string') {
+          context.fillStyle = (settings('labelHoverColor') === 'node') ?
+            (node.color || settings('defaultNodeColor')) :
+            settings('defaultLabelHoverColor');
+
+          context.fillText(
+            node.label,
+            Math.round(node[prefix + 'x'] + size + 3),
+            Math.round(node[prefix + 'y'] + fontSize / 3)
+          );
+        }
       };
 
       // ================ /alternative rendering =====================