From 16e6c71cc0106d367cc9ffe53f566f5fd3225c5d Mon Sep 17 00:00:00 2001
From: Alexis Girault <alexis.girault@kitware.com>
Date: Wed, 14 Mar 2018 14:45:02 -0400
Subject: [PATCH] fix(Plane and Box): avoid slowing down evaluateFunction

evaluateFunction can be called in an interactive fashion, requiring it to
stay fast. However, spreading the input then creating a empty array and
concatenating the spread inputs is very slow.
---
 Sources/Common/DataModel/Box/index.js         | 11 ++--------
 Sources/Common/DataModel/Box/test/testBox.js  | 21 ++++++++++--------
 Sources/Common/DataModel/Plane/index.js       | 22 +++++++++----------
 .../Common/DataModel/Plane/test/testPlane.js  |  9 ++++----
 4 files changed, 29 insertions(+), 34 deletions(-)

diff --git a/Sources/Common/DataModel/Box/index.js b/Sources/Common/DataModel/Box/index.js
index dbb6e88e658..a74331ad0dc 100644
--- a/Sources/Common/DataModel/Box/index.js
+++ b/Sources/Common/DataModel/Box/index.js
@@ -118,15 +118,8 @@ function vtkBox(publicAPI, model) {
 
   publicAPI.getBounds = () => model.bbox.getBounds();
 
-  publicAPI.evaluateFunction = (...x) => {
-    let point = [].concat(x);
-    if (Array.isArray(x[0])) {
-      point = x[0];
-    }
-
-    if (point.length !== 3) {
-      return Number.MAX_VALUE;
-    }
+  publicAPI.evaluateFunction = (x, y, z) => {
+    const point = Array.isArray(x) ? x : [x, y, z];
 
     let diff;
     let dist;
diff --git a/Sources/Common/DataModel/Box/test/testBox.js b/Sources/Common/DataModel/Box/test/testBox.js
index 87db1d87d57..194c99ca28e 100644
--- a/Sources/Common/DataModel/Box/test/testBox.js
+++ b/Sources/Common/DataModel/Box/test/testBox.js
@@ -63,17 +63,20 @@ test('Test vtkBox evaluateFunction', (t) => {
   const box = vtkBox.newInstance();
   box.setBounds(bounds);
 
-  const point1 = [0.0, 0.0, 0.0];
-  const evaluation1 = box.evaluateFunction(point1);
-  t.equal(evaluation1, -50);
+  let point = [0.0, 0.0, 0.0];
+  let res = box.evaluateFunction(point);
+  t.equal(res, -50);
 
-  const point2 = [100.0, 0.0, 0.0];
-  const evaluation2 = box.evaluateFunction(point2);
-  t.equal(evaluation2, 50);
+  point = [100.0, 0.0, 0.0];
+  res = box.evaluateFunction(point);
+  t.equal(res, 50);
 
-  const point3 = [50.0, 0.0, 0.0];
-  const evaluation3 = box.evaluateFunction(point3);
-  t.equal(evaluation3, 0);
+  point = [50.0, 0.0, 0.0];
+  res = box.evaluateFunction(point);
+  t.equal(res, 0);
+
+  res = box.evaluateFunction(...point);
+  t.equal(res, 0);
 
   t.end();
 });
diff --git a/Sources/Common/DataModel/Plane/index.js b/Sources/Common/DataModel/Plane/index.js
index b848aa544af..1b8e0fed23b 100644
--- a/Sources/Common/DataModel/Plane/index.js
+++ b/Sources/Common/DataModel/Plane/index.js
@@ -153,20 +153,18 @@ export function vtkPlane(publicAPI, model) {
     generalizedProjectPoint(x, model.origin, model.normal, xproj);
   };
 
-  publicAPI.evaluateFunction = (...x) => {
-    let point = [].concat(x);
-    if (Array.isArray(x[0])) {
-      point = x[0];
+  publicAPI.evaluateFunction = (x, y, z) => {
+    if (!Array.isArray(x)) {
+      return (
+        model.normal[0] * (x - model.origin[0]) +
+        model.normal[1] * (y - model.origin[1]) +
+        model.normal[2] * (z - model.origin[2])
+      );
     }
-
-    if (point.length !== 3) {
-      return Number.MAX_VALUE;
-    }
-
     return (
-      model.normal[0] * (point[0] - model.origin[0]) +
-      model.normal[1] * (point[1] - model.origin[1]) +
-      model.normal[2] * (point[2] - model.origin[2])
+      model.normal[0] * (x[0] - model.origin[0]) +
+      model.normal[1] * (x[1] - model.origin[1]) +
+      model.normal[2] * (x[2] - model.origin[2])
     );
   };
 
diff --git a/Sources/Common/DataModel/Plane/test/testPlane.js b/Sources/Common/DataModel/Plane/test/testPlane.js
index 8e11dd659d4..355c7162be1 100644
--- a/Sources/Common/DataModel/Plane/test/testPlane.js
+++ b/Sources/Common/DataModel/Plane/test/testPlane.js
@@ -141,14 +141,15 @@ test('Test vtkPlane evaluateFunction', (t) => {
   plane.setOrigin(0.0, 0.0, 0.0);
   plane.setNormal(1.0, 1.0, 1.0);
 
-  let res = plane.evaluateFunction([1.0, 1.0, 1.0]);
+  const point = [1.0, 1.0, 1.0];
+  let res = plane.evaluateFunction(point);
   t.equal(res, 3);
 
-  res = plane.evaluateFunction(1.0, 1.0, 1.0);
+  res = plane.evaluateFunction(...point);
   t.equal(res, 3);
 
-  res = plane.evaluateFunction(1.0, 1.0, 1.0, 0.0);
-  t.equal(res, Number.MAX_VALUE);
+  res = plane.evaluateFunction(...point, 1.0); // ignore last value
+  t.equal(res, 3);
 
   t.end();
 });