From 99c1a0a35dd52ddec26551de75656cdda7149b39 Mon Sep 17 00:00:00 2001
From: Neil <neil.a.macphee@gmail.com>
Date: Fri, 10 Feb 2023 11:34:24 -0500
Subject: [PATCH] fix(trackball): rotate was wrong on mouse drag (#424)

* created new vector for the image, changed the vector used in this.rotateCamers()

* cleaning up code

* removing unneeded code

* removing leftVec of image, using rightVec for forwardVec calculation

* removed unsused library

* fixed x-axis rotation issue with polyData actor example
---
 packages/tools/src/tools/TrackballRotateTool.ts | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/packages/tools/src/tools/TrackballRotateTool.ts b/packages/tools/src/tools/TrackballRotateTool.ts
index ee0eb22df9..2e70a9b921 100644
--- a/packages/tools/src/tools/TrackballRotateTool.ts
+++ b/packages/tools/src/tools/TrackballRotateTool.ts
@@ -113,20 +113,23 @@ class TrackballRotateTool extends BaseTool {
         rotateIncrementDegrees;
 
       const upVec = camera.viewUp;
+      const atV = camera.viewPlaneNormal;
+      const rightV: Types.Point3 = [0, 0, 0];
+      const forwardV: Types.Point3 = [0, 0, 0];
+
+      vtkMath.cross(upVec, atV, rightV);
+      vtkMath.normalize(rightV);
+
+      vtkMath.cross(atV, rightV, forwardV);
+      vtkMath.normalize(forwardV);
       vtkMath.normalize(upVec);
 
-      this.rotateCamera(viewport, centerWorld, upVec, angleX);
+      this.rotateCamera(viewport, centerWorld, forwardV, angleX);
 
       const angleY =
         (normalizedPreviousPosition[1] - normalizedPosition[1]) *
         rotateIncrementDegrees;
 
-      const atV = camera.viewPlaneNormal;
-      const upV = camera.viewUp;
-      const rightV: Types.Point3 = [0, 0, 0];
-      vtkMath.cross(upV, atV, rightV);
-      vtkMath.normalize(rightV);
-
       this.rotateCamera(viewport, centerWorld, rightV, angleY);
 
       viewport.render();