fix #2441 - don't attempt to draw empty option items

- refs to regl2d objects are kept even when options objects are emptied
  e.g. in the case of legend visible toggles, so don't try to redraw
  regl2d object with old options.

Author: etpinard

src/traces/scattergl/index.js

@@ -556,21 +556,24 @@ function sceneUpdate(gd, subplot) {
         scene.draw = function draw() {
             var i;
             for(i = 0; i < scene.count; i++) {
-                if(scene.fill2d) scene.fill2d.draw(i);
+                if(scene.fill2d && scene.fillOptions[i]) {
+                    // must do all fills first
+                    scene.fill2d.draw(i);
+                }
             }
             for(i = 0; i < scene.count; i++) {
-                if(scene.line2d) {
+                if(scene.line2d && scene.lineOptions[i]) {
                     scene.line2d.draw(i);
                 }
-                if(scene.error2d) {
+                if(scene.error2d && scene.errorXOptions[i]) {
                     scene.error2d.draw(i);
+                }
+                if(scene.error2d && scene.errorYOptions[i]) {
                     scene.error2d.draw(i + scene.count);
                 }
-                if(scene.scatter2d) {
+                if(scene.scatter2d && scene.markerOptions[i] && (!scene.selectBatch || !scene.selectBatch[i])) {
                     // traces in no-selection mode
-                    if(!scene.selectBatch || !scene.selectBatch[i]) {
-                        scene.scatter2d.draw(i);
-                    }
+                    scene.scatter2d.draw(i);
                 }
             }
 

test/jasmine/tests/gl2d_plot_interact_test.js

@@ -379,6 +379,48 @@ describe('@gl Test gl2d plots', function() {
         .then(done);
     });
 
+    it('should be able to toggle trace with different modes', function(done) {
+        Plotly.newPlot(gd, [{
+            // a trace with all regl2d objects
+            type: 'scattergl',
+            y: [1, 2, 1],
+            error_x: {value: 10},
+            error_y: {value: 10},
+            fill: 'tozeroy'
+        }, {
+            type: 'scattergl',
+            mode: 'markers',
+            y: [0, 1, -1]
+        }])
+        .then(function() {
+            var scene = gd._fullLayout._plots.xy._scene;
+            spyOn(scene.fill2d, 'draw');
+            spyOn(scene.line2d, 'draw');
+            spyOn(scene.error2d, 'draw');
+            spyOn(scene.scatter2d, 'draw');
+
+            return Plotly.restyle(gd, 'visible', 'legendonly', [0]);
+        })
+        .then(function() {
+            var scene = gd._fullLayout._plots.xy._scene;
+            expect(scene.fill2d.draw).toHaveBeenCalledTimes(0);
+            expect(scene.line2d.draw).toHaveBeenCalledTimes(0);
+            expect(scene.error2d.draw).toHaveBeenCalledTimes(0);
+            expect(scene.scatter2d.draw).toHaveBeenCalledTimes(1);
+
+            return Plotly.restyle(gd, 'visible', true, [0]);
+        })
+        .then(function() {
+            var scene = gd._fullLayout._plots.xy._scene;
+            expect(scene.fill2d.draw).toHaveBeenCalledTimes(1);
+            expect(scene.line2d.draw).toHaveBeenCalledTimes(1);
+            expect(scene.error2d.draw).toHaveBeenCalledTimes(2, 'twice for x AND y');
+            expect(scene.scatter2d.draw).toHaveBeenCalledTimes(3, 'both traces have markers');
+        })
+        .catch(fail)
+        .then(done);
+    });
+
     it('@noCI should display selection of big number of regular points', function(done) {
         // generate large number of points
         var x = [], y = [], n = 2e2, N = n * n;