added start end and size attributes

Author: archmoj

package-lock.json

@@ -43,6 +43,40 @@ function makeContourAttr(axLetter) {
                 'dimension are drawn.'
             ].join(' ')
         },
+        start: {
+            valType: 'number',
+            dflt: null,
+            role: 'style',
+            editType: 'plot',
+         // impliedEdits: {'^autocontour': false},
+            description: [
+                'Sets the starting contour level value.',
+                'Must be less than `contours.end`'
+            ].join(' ')
+        },
+        end: {
+            valType: 'number',
+            dflt: null,
+            role: 'style',
+            editType: 'plot',
+         // impliedEdits: {'^autocontour': false},
+            description: [
+                'Sets the end contour level value.',
+                'Must be more than `contours.start`'
+            ].join(' ')
+        },
+        size: {
+            valType: 'number',
+            dflt: null,
+            min: 0,
+            role: 'style',
+            editType: 'plot',
+         // impliedEdits: {'^autocontour': false},
+            description: [
+                'Sets the step between each contour level.',
+                'Must be positive.'
+            ].join(' ')
+        },
         locations: {
             valType: 'data_array',
             dflt: false,

src/traces/surface/attributes.js

@@ -25,6 +25,9 @@ function SurfaceTrace(scene, surface, uid) {
     this.surface = surface;
     this.data = null;
     this.showContour = [false, false, false];
+    this.contourStart = [null, null, null];
+    this.contourEnd = [null, null, null];
+    this.contourSize = [0, 0, 0];
     this.contourLocations = [[], [], []];
     this.contourRelative = [0, 0]; // note: only available on x & y not z.
     this.minValues = [Infinity, Infinity, Infinity];
@@ -412,6 +415,22 @@ proto.setContourLevels = function() {
                     insertIfNewLevel(newLevels[i], value);
                 }
             }
+
+            if(
+                this.contourSize[i] > 0 &&
+                this.contourStart[i] !== null &&
+                this.contourEnd[i] !== null &&
+                this.contourEnd[i] > this.contourStart[i]
+            ) {
+                useNewLevels[i] = true;
+
+                for(j = this.contourStart[i]; j < this.contourEnd[i]; j += this.contourSize[i]) {
+                    value = j * this.scene.dataScale[i];
+
+                    insertIfNewLevel(newLevels[i], value);
+                }
+            }
+
         }
     }
 
@@ -613,10 +632,19 @@ proto.update = function(data) {
             }
             params.contourWidth[i] = contourParams.width;
 
+            this.contourStart[i] = contourParams.start;
+            this.contourEnd[i] = contourParams.end;
+            this.contourSize[i] = contourParams.size;
+
             this.contourLocations[i] = contourParams.locations;
             if(i < 2) this.contourRelative[i] = contourParams.relative;
         } else {
             this.showContour[i] = false;
+
+            this.contourStart[i] = null;
+            this.contourEnd[i] = null;
+            this.contourSize[i] = 0;
+
             this.contourLocations[i] = [];
             if(i < 2) this.contourRelative[i] = 0;
         }

src/traces/surface/convert.js

@@ -82,6 +82,10 @@ module.exports = function supplyDefaults(traceIn, traceOut, defaultColor, layout
             coerce(contourDim + '.highlightcolor');
             coerce(contourDim + '.highlightwidth');
         }
+
+        coerce(contourDim + '.start');
+        coerce(contourDim + '.end');
+        coerce(contourDim + '.size');
     }
 
     // backward compatibility block

src/traces/surface/defaults.js

@@ -0,0 +1,40 @@
+{
+    "data": [
+        {
+            "type": "surface",
+            "contours": {
+                "x": { "show": true, "start": 0.1, "end": 0.4, "size": 0.05 },
+                "y": { "show": true, "start": 0.1, "end": 0.4, "size": 0.05 },
+                "z": { "show": true, "start": 0.1, "end": 0.4, "size": 0.05 }
+            },
+            "x": [0, 0.25, 0.5, 0.75, 1],
+            "y": [0, 0.25, 0.5, 0.75, 1],
+            "z": [
+                [0, 1, 0, 1, 0],
+                [1, 0, 1, 0, 1],
+                [0, 1, 0, 1, 0],
+                [1, 0, 1, 0, 1],
+                [0, 1, 0, 1, 0]
+            ]
+        }
+    ],
+    "layout": {
+        "title": "Surface contours using start, end and size",
+        "width": 900,
+        "height": 600,
+        "scene": {
+            "xaxis": { "nticks": 12 },
+            "yaxis": { "nticks": 12 },
+            "zaxis": { "nticks": 4 },
+            "camera": {
+                "eye": { "x": 0, "y": -1, "z": 0.75 },
+                "center": { "x": 0, "y": 0, "z": 0 }
+            },
+            "aspectratio": {
+                "x": 1,
+                "y": 1,
+                "z": 0.2
+            }
+        }
+    }
+}