Adaptive Physics Time Step (#989)

.github/workflows/FissionESLintFormat.yml

@@ -28,17 +28,25 @@ jobs:
         cd fission
         npm run lint
       continue-on-error: true
+    - name: Check EsLint
+      run: |
+        if [ ${{ steps.linter-validation.outcome }} == "success" ]; then
+          echo "EsLint Validation Passed"
+        else
+          echo "EsLint Validation Failed"
+          exit 1
+        fi
     - name: Prettier
       id: prettier-validation
       run: |
         cd fission
         npm run prettier
       continue-on-error: true
-    - name: Check Success
+    - name: Check Prettier
       run: |
-        if [ ${{ steps.linter-validation.outcome }} == "success" ]; then
-          echo "Format Validation Passed"
+        if [ ${{ steps.prettier-validation.outcome }} == "success" ]; then
+          echo "Prettier Validation Passed"
         else
-          echo "Format Validation Failed"
+          echo "Prettier Validation Failed"
           exit 1
         fi

fission/package.json

@@ -6,12 +6,12 @@
   "scripts": {
     "dev": "vite --open",
     "build": "tsc && vite build",
-    "lint": "eslint . --ext ts,tsx --report-unused-disable-directives",
     "preview": "vite preview --base=/fission/",
     "test": "vitest",
-    "lint:fix": "bun run lint --fix || npm run lint --fix",
+    "lint": "eslint . --ext ts,tsx --report-unused-disable-directives",
+    "lint:fix": "eslint . --ext ts,tsx --report-unused-disable-directives --fix",
     "prettier": "bun x prettier src --check || npx prettier src --check",
-    "prettier:fix": "bun run prettier --write || npm run prettier --write",
+    "prettier:fix": "bun x prettier src --write || npx prettier src --write",
     "format": "(bun run prettier:fix && bun run lint:fix) || (npm run prettier:fix && npm run lint:fix)",
     "build:prod": "tsc && vite build --base=/fission/",
     "assetpack": "curl -o public/assetpack.zip https://synthesis.autodesk.com/Downloadables/assetpack.zip && tar -xf public/assetpack.zip -C public/",

fission/src/mirabuf/MirabufParser.ts

@@ -91,7 +91,8 @@ class MirabufParser {
         }
 
         // 1: Initial Rigidgroups from ancestorial breaks in joints
-        (Object.keys(assembly.data!.joints!.jointInstances!) as string[]).forEach(key => {
+        const jointInstanceKeys = Object.keys(assembly.data!.joints!.jointInstances!) as string[]
+        jointInstanceKeys.forEach(key => {
             if (key != GROUNDED_JOINT_ID) {
                 const jInst = assembly.data!.joints!.jointInstances![key]
                 const [ancestorA, ancestorB] = this.FindAncestorialBreak(jInst.parentPart!, jInst.childPart!)

fission/src/systems/physics/PhysicsSystem.ts

@@ -31,8 +31,18 @@ const LAYER_GHOST = 10
 // Please update this accordingly.
 const COUNT_OBJECT_LAYERS = 11
 
-export const SIMULATION_PERIOD = 1.0 / 120.0
-const STANDARD_SUB_STEPS = 3
+export const STANDARD_SIMULATION_PERIOD = 1.0 / 60.0
+const MIN_SIMULATION_PERIOD = 1.0 / 120.0
+const MAX_SIMULATION_PERIOD = 1.0 / 10.0
+const MIN_SUBSTEPS = 2
+const MAX_SUBSTEPS = 6
+const STANDARD_SUB_STEPS = 4
+const TIMESTEP_ADJUSTMENT = 0.0001
+
+let lastDeltaT = STANDARD_SIMULATION_PERIOD
+export function GetLastDeltaT(): number {
+    return lastDeltaT
+}
 
 // Friction constants
 const FLOOR_FRICTION = 0.7
@@ -704,8 +714,18 @@ class PhysicsSystem extends WorldSystem {
         return this._joltPhysSystem.GetBodyLockInterface().TryGetBody(bodyId)
     }
 
-    public Update(_: number): void {
-        this._joltInterface.Step(SIMULATION_PERIOD, STANDARD_SUB_STEPS)
+    public Update(deltaT: number): void {
+        const diffDeltaT = deltaT - lastDeltaT
+
+        lastDeltaT = lastDeltaT + Math.min(TIMESTEP_ADJUSTMENT, Math.max(-TIMESTEP_ADJUSTMENT, diffDeltaT))
+        lastDeltaT = Math.min(MAX_SIMULATION_PERIOD, Math.max(MIN_SIMULATION_PERIOD, lastDeltaT))
+
+        let substeps = Math.max(1, Math.floor((lastDeltaT / STANDARD_SIMULATION_PERIOD) * STANDARD_SUB_STEPS))
+        substeps = Math.min(MAX_SUBSTEPS, Math.max(MIN_SUBSTEPS, substeps))
+
+        console.log(`DeltaT: ${lastDeltaT.toFixed(5)}, Substeps: ${substeps}`)
+
+        this._joltInterface.Step(lastDeltaT, substeps)
     }
 
     public Destroy(): void {

fission/src/systems/simulation/driver/HingeDriver.ts

@@ -1,6 +1,6 @@
 import Jolt from "@barclah/jolt-physics"
 import Driver, { DriverControlMode } from "./Driver"
-import { SIMULATION_PERIOD } from "@/systems/physics/PhysicsSystem"
+import { GetLastDeltaT } from "@/systems/physics/PhysicsSystem"
 import JOLT from "@/util/loading/JoltSyncLoader"
 
 class HingeDriver extends Driver {
@@ -61,7 +61,7 @@ class HingeDriver extends Driver {
         const springSettings = motorSettings.mSpringSettings
 
         // These values were selected based on the suggestions of the documentation for stiff control.
-        springSettings.mFrequency = 20 * (1.0 / SIMULATION_PERIOD)
+        springSettings.mFrequency = 20 * (1.0 / GetLastDeltaT())
         springSettings.mDamping = 0.995
 
         motorSettings.mSpringSettings = springSettings

fission/src/systems/simulation/driver/SliderDriver.ts

@@ -1,6 +1,6 @@
 import Jolt from "@barclah/jolt-physics"
 import Driver, { DriverControlMode } from "./Driver"
-import { SIMULATION_PERIOD } from "@/systems/physics/PhysicsSystem"
+import { GetLastDeltaT } from "@/systems/physics/PhysicsSystem"
 import JOLT from "@/util/loading/JoltSyncLoader"
 
 class SliderDriver extends Driver {
@@ -62,7 +62,7 @@ class SliderDriver extends Driver {
 
         const motorSettings = this._constraint.GetMotorSettings()
         const springSettings = motorSettings.mSpringSettings
-        springSettings.mFrequency = 20 * (1.0 / SIMULATION_PERIOD)
+        springSettings.mFrequency = 20 * (1.0 / GetLastDeltaT())
         springSettings.mDamping = 0.999
 
         motorSettings.mSpringSettings = springSettings

fission/src/ui/modals/mirabuf/ImportMirabufModal.tsx

@@ -33,13 +33,15 @@ const ImportMirabufModal: React.FC<ModalPropsImpl> = ({ modalId }) => {
     const [selectedFolder, setSelectedFolder] = useState<Folder | undefined>(undefined)
 
     const [hubs, setHubs] = useState<Hub[] | undefined>(undefined)
+    // prettier-ignore
     useEffect(() => {
         (async () => {
             setHubs(await getHubs())
         })()
     }, [])
 
     const [projects, setProjects] = useState<Project[] | undefined>(undefined)
+    // prettier-ignore
     useEffect(() => {
         (async () => {
             if (selectedHub) {
@@ -49,6 +51,7 @@ const ImportMirabufModal: React.FC<ModalPropsImpl> = ({ modalId }) => {
     }, [selectedHub])
 
     const [folderData, setFolderData] = useState<Data[] | undefined>(undefined)
+    // prettier-ignore
     useEffect(() => {
         (async () => {
             if (selectedProject) {

fission/src/ui/modals/spawning/SpawningModals.tsx

@@ -37,6 +37,7 @@ export const AddRobotsModal: React.FC<ModalPropsImpl> = ({ modalId }) => {
 
     const [remoteRobots, setRemoteRobots] = useState<MirabufEntry[] | null>(null)
 
+    // prettier-ignore
     useEffect(() => {
         (async () => {
             fetch("/api/mira/manifest.json")
@@ -95,6 +96,7 @@ export const AddFieldsModal: React.FC<ModalPropsImpl> = ({ modalId }) => {
 
     const [remoteFields, setRemoteFields] = useState<MirabufEntry[] | null>(null)
 
+    // prettier-ignore
     useEffect(() => {
         (async () => {
             fetch("/api/mira/manifest.json")

fission/src/util/dom.ts

@@ -23,6 +23,7 @@ export const mousePosition = (x: number, y: number) => {
     el?.dispatchEvent(event)
 }
 
+// prettier-ignore
 export const addGlobalFunc = <T>(name: string, func: (...args: any[]) => T) => {
     (window as any)[name] = func
 }