From 4b50540c383cd2a67d79110c9bd414ce479658dc Mon Sep 17 00:00:00 2001
From: Paul Elliott <paul.elliott@kitware.com>
Date: Thu, 30 May 2024 17:10:17 -0400
Subject: [PATCH] fix: only reset camera in views

Avoids 3d reset in viewport from overriding
2d reset in view-2d if timing is strange
---
 packages/viewer/src/view-2d.ts  | 54 ++++++++++++++++++++++++---------
 packages/viewer/src/viewport.ts | 20 +-----------
 2 files changed, 41 insertions(+), 33 deletions(-)

diff --git a/packages/viewer/src/view-2d.ts b/packages/viewer/src/view-2d.ts
index 1f802369..95a68b05 100644
--- a/packages/viewer/src/view-2d.ts
+++ b/packages/viewer/src/view-2d.ts
@@ -5,6 +5,7 @@ import {
   enqueueActions,
   fromPromise,
   setup,
+  stateIn,
 } from 'xstate';
 import {
   MultiscaleSpatialImage,
@@ -147,17 +148,18 @@ export const view2d = setup({
     ),
     findDefaultAxis: fromPromise(
       async ({
-        input: { image },
+        input: { image, scale },
       }: {
         input: {
           image: MultiscaleSpatialImage;
+          scale: number;
         };
       }) => {
-        const ijkSpacing = await image.scaleSpacing(image.coarsestScale);
+        const ijkSpacing = await image.scaleSpacing(scale);
         if (ijkSpacing.length > 3) {
           ijkSpacing.push(0);
         }
-        const shape = image.scaleInfos[image.coarsestScale].arrayShape;
+        const shape = image.scaleInfos[scale].arrayShape;
         const shape3d = ensuredDims(0, ['x', 'y', 'z'], shape);
         const shapeArray = XYZ.map((axis) => shape3d.get(axis)!);
         return computeMinSizeAxis(ijkSpacing, shapeArray);
@@ -185,7 +187,6 @@ export const view2d = setup({
       const withAxis = { ...currentPose };
       withAxis.rotation = toRotation(image.direction, axis);
 
-      await image.scaleIndexToWorld(scale); // ??? TODO: this makes reset work...
       const indexToWorld = await image.scaleIndexToWorld(scale);
       const indexBounds = image.getIndexExtent(scale);
       const corners = getCorners(indexBounds);
@@ -257,14 +258,18 @@ export const view2d = setup({
           ],
           target: '.findingNewImageDefaults',
         },
-        setSlice: {
-          actions: [assign({ slice: ({ event }) => event.slice })],
-          target: '.buildingImage',
-        },
-        setScale: {
-          actions: [assign({ scale: ({ event }) => event.scale })],
-          target: '.buildingImage',
-        },
+        setSlice: [
+          // if buildingImage, rebuild image
+          {
+            guard: stateIn('view2d.buildingImage'),
+            target: '.buildingImage',
+            actions: [assign({ slice: ({ event }) => event.slice })],
+          },
+          // else eventually going to buildingImage
+          {
+            actions: [assign({ slice: ({ event }) => event.slice })],
+          },
+        ],
         setViewport: {
           actions: [
             assign({
@@ -292,14 +297,21 @@ export const view2d = setup({
       },
       initial: 'idle',
       states: {
-        idle: {},
+        idle: {
+          on: {
+            setScale: {
+              actions: [assign({ scale: ({ event }) => event.scale })],
+            },
+          },
+        },
         findingNewImageDefaults: {
           invoke: {
             input: ({ context }) => {
-              const { image } = context;
+              const { image, scale } = context;
               if (!image) throw new Error('No image available');
               return {
                 image,
+                scale,
               };
             },
             src: 'findDefaultAxis',
@@ -321,6 +333,13 @@ export const view2d = setup({
               target: 'buildingImage',
             },
           },
+          on: {
+            setScale: {
+              actions: [assign({ scale: ({ event }) => event.scale })],
+              target: '.',
+              reenter: true,
+            },
+          },
         },
         buildingImage: {
           invoke: {
@@ -348,6 +367,13 @@ export const view2d = setup({
                 }),
               ],
             },
+            on: {
+              setScale: {
+                actions: [assign({ scale: ({ event }) => event.scale })],
+                target: '.',
+                reenter: true,
+              },
+            },
           },
         },
       },
diff --git a/packages/viewer/src/viewport.ts b/packages/viewer/src/viewport.ts
index 2d9265f3..cc2f5593 100644
--- a/packages/viewer/src/viewport.ts
+++ b/packages/viewer/src/viewport.ts
@@ -2,7 +2,7 @@ import { Actor, AnyActorRef, assign, sendParent, setup } from 'xstate';
 import { ReadonlyMat4 } from 'gl-matrix';
 
 import { MultiscaleSpatialImage } from '@itk-viewer/io/MultiscaleSpatialImage.js';
-import { cameraMachine, Camera, reset3d } from './camera.js';
+import { cameraMachine, Camera } from './camera.js';
 import { CreateChild } from './children.js';
 
 type Context = {
@@ -48,22 +48,6 @@ export const viewportMachine = setup({
         actor.send(event);
       });
     },
-    resetCameraPose: async ({ context: { image, resolution: dims }, self }) => {
-      const { camera } = self.getSnapshot().children;
-      if (!image || !camera) return;
-
-      const aspect = (() => {
-        return dims[1] && dims[0] ? dims[0] / dims[1] : 1;
-      })();
-      const bounds = await image.getWorldBounds(image.coarsestScale);
-      const { pose: currentPose, verticalFieldOfView } =
-        camera.getSnapshot().context;
-      const pose = reset3d(currentPose, verticalFieldOfView, bounds, aspect);
-      camera.send({
-        type: 'setPose',
-        pose,
-      });
-    },
   },
 }).createMachine({
   id: 'viewport',
@@ -104,7 +88,6 @@ export const viewportMachine = setup({
             assign({
               image: ({ event: { image } }: { event: SetImageEvent }) => image,
             }),
-            'resetCameraPose',
             'forwardToSpawned',
           ],
         },
@@ -114,7 +97,6 @@ export const viewportMachine = setup({
               camera: ({ event: { camera } }: { event: SetCameraEvent }) =>
                 camera,
             }),
-            'resetCameraPose',
             'forwardToSpawned',
           ],
         },