store and use ticklabel bounding boxes to increase pad for inside labels

Author: archmoj

src/plots/cartesian/autorange.js

@@ -225,14 +225,24 @@ function makePadFn(ax, max) {
                 anchorAxis.side === 'right'
             )
         )) {
-            var fontSize = anchorAxis.tickfont ? anchorAxis.tickfont.size : 12;
-            var newPad = fontSize * (ax._id.charAt(0) === 'x' ? 4 : 1);
+            var isX = ax._id.charAt(0) === 'x';
+
+            var morePad = 0;
+            if(anchorAxis._vals) {
+                // use bounding boxes
+                morePad = 0;
+                anchorAxis._vals.forEach(function(t) {
+                    if(t.bb) {
+                        morePad = Math.max(morePad, isX ? t.bb.width : t.bb.height);
+                    }
+                });
+            }
 
             if(anchorAxis.ticks === 'inside' && anchorAxis.ticklabelposition === 'inside') {
-                newPad += anchorAxis.ticklen || 0;
+                morePad += anchorAxis.ticklen || 0;
             }
 
-            extrappad = Math.max(extrappad, newPad);
+            extrappad += morePad;
         }
     }
 

src/plots/cartesian/axes.js

@@ -3140,6 +3140,20 @@ axes.drawLabels = function(gd, ax, opts) {
         });
     }
 
+    function computeFinalTickLabelBoundingBoxes() {
+        tickLabels.each(function(d, i) {
+            var thisLabel = selectTickLabel(this);
+            ax._vals[i].bb = Drawing.bBox(thisLabel.node());
+        });
+    }
+
+    if(
+        (ax._anchorAxis || {}).autorange &&
+        (ax.ticklabelposition || '').indexOf('inside') !== -1
+    ) {
+        seq.push(computeFinalTickLabelBoundingBoxes);
+    }
+
     var done = Lib.syncOrAsync(seq);
     if(done && done.then) gd._promises.push(done);
     return done;