2d physics on WASM platform

Author: fabmax

kool-demo/src/wasmJsMain/kotlin/Main.kt

@@ -1,12 +1,14 @@
 import de.fabmax.kool.KoolApplication
 import de.fabmax.kool.KoolConfigWasm
 import de.fabmax.kool.demo.demo
+import de.fabmax.kool.physics2d.Physics2d
 
 fun main() = KoolApplication(
     KoolConfigWasm(
         isGlobalKeyEventGrabbing = true,
         deviceScaleLimit = 1.5,
     )
 ) {
+    Physics2d.loadPhysics2d()
     demo(null, ctx)
 }

kool-physics-2d/src/jsMain/kotlin/box2d/Box2dWasmLoader.kt

@@ -4,25 +4,27 @@
 
 package box2d
 
-import kotlinx.coroutines.asDeferred             
+import kotlinx.coroutines.await
 import kotlin.js.Promise
 
 @JsModule("kool-box2d-wasm")
 private external val Box2D: () -> Promise<dynamic>
 
-object Box2dWasmLoader {
-    @JsName("box2dWasm")
-    internal var box2dWasm: dynamic = null
+internal actual object Box2dWasmLoader {
+    private lateinit var box2dWasmModule: JsAny
+    internal actual val box2dWasm: JsAny get() = box2dWasmModule
     private val box2dWasmPromise = Box2D()
-    internal var box2dWasmDeferred = box2dWasmPromise.asDeferred()
+    private var isLoaded: Boolean = false
 
-    val isLoaded: Boolean get() = box2dWasmDeferred.isCompleted
-
-    suspend fun loadModule() {
+    actual suspend fun loadModule() {
         if (!isLoaded) {
-            box2dWasmPromise.then { module: dynamic -> box2dWasm = module }
+            box2dWasmPromise.then<JsAny> { module ->
+                box2dWasmModule = module
+                module
+            }
         }
-        box2dWasmDeferred.await()
+        box2dWasmPromise.await<JsAny>()
+        isLoaded = true
     }
 
     fun checkIsLoaded() {
@@ -31,7 +33,9 @@ object Box2dWasmLoader {
         }
     }
 
-    fun destroy(nativeObject: Any) {
-        box2dWasm.destroy(nativeObject)
+    actual fun destroy(nativeObject: JsAny) {
+        destroyJsNativeAny(box2dWasm, nativeObject)
     }
-}
+}
+
+private fun destroyJsNativeAny(module: JsAny, obj: JsAny): Unit = js("module.destroy(obj)")

kool-physics-2d/src/jsMain/kotlin/box2d/prototypes/Prototypes.kt

@@ -0,0 +1,37 @@
+package box2d
+
+import kotlinx.coroutines.await
+import kotlin.js.Promise
+
+@JsModule("kool-box2d-wasm")
+private external val Box2D: () -> Promise<JsAny>
+
+internal actual object Box2dWasmLoader {
+    private var box2dWasmModule: JsAny? = null
+    internal actual val box2dWasm: JsAny get() = requireNotNull(box2dWasmModule) { "Module 'kool-box2d-wasm' is not loaded" }
+    private val box2dWasmPromise = Box2D()
+    private var isLoaded: Boolean = false
+
+    actual suspend fun loadModule() {
+        if (!isLoaded) {
+            box2dWasmPromise.then<JsAny> { module ->
+                box2dWasmModule = module
+                module
+            }
+        }
+        box2dWasmPromise.await<JsAny>()
+        isLoaded = true
+    }
+
+    fun checkIsLoaded() {
+        if (!isLoaded) {
+            throw IllegalStateException("Module 'kool-box2d-wasm' is not loaded. Call loadModule() first and wait for loading to be finished.")
+        }
+    }
+
+    actual fun destroy(nativeObject: JsAny) {
+        destroyJsNativeAny(box2dWasm, nativeObject)
+    }
+}
+
+private fun destroyJsNativeAny(module: JsAny, obj: JsAny): Unit = js("module.destroy(obj)")