ConstVehicleConstraint: add the getWheelPositionAndRotation() method

Author: stephengold

src/main/java/com/github/stephengold/joltjni/VehicleConstraint.java

@@ -24,6 +24,7 @@ of this software and associated documentation files (the "Software"), to deal
 import com.github.stephengold.joltjni.readonly.ConstVehicleConstraint;
 import com.github.stephengold.joltjni.readonly.ConstVehicleConstraintSettings;
 import com.github.stephengold.joltjni.readonly.Vec3Arg;
+import java.nio.DoubleBuffer;
 import java.nio.FloatBuffer;
 
 /**
@@ -401,6 +402,33 @@ public RMat44 getWheelWorldTransform(
         return result;
     }
 
+    /**
+     * Copy the world transform of the specified wheel. The constraint is
+     * unaffected.
+     *
+     * @param wheelIndex the index of the wheel to query (≥0)
+     * @param right the wheel's axis of rotation (a unit vector in the wheel's
+     * model space)
+     * @param up the "up" direction (a unit vector in the wheel's model space)
+     * @param storePosition storage for the translation component (not null,
+     * modified)
+     * @param storeRotation storage for the rotation component (not null,
+     * modified)
+     */
+    @Override
+    public void getWheelPositionAndRotation(int wheelIndex, Vec3Arg right,
+            Vec3Arg up, RVec3 storePosition, Quat storeRotation) {
+        long constraintVa = va();
+        DoubleBuffer storeDoubles = Temporaries.doubleBuffer1.get();
+        FloatBuffer storeFloats = Temporaries.floatBuffer1.get();
+        right.copyTo(storeFloats);
+        up.copyTo(storeFloats, 3);
+        getWheelWorldTransformComponents(
+                constraintVa, wheelIndex, storeDoubles, storeFloats);
+        storePosition.set(storeDoubles);
+        storeRotation.set(storeFloats);
+    }
+
     /**
      * Copy the "up" direction based on gravity. The constraint is unaffected.
      *
@@ -506,6 +534,9 @@ native static void getWheelLocalBasis(
     native static long getWheelWorldTransform(long constraintVa, int wheelIndex,
             float rx, float ry, float rz, float ux, float uy, float uz);
 
+    native static void getWheelWorldTransformComponents(long constraintVa,
+            int wheelIndex, DoubleBuffer storeDoubles, FloatBuffer storeFloats);
+
     native static void getWorldUp(long constraintVa, FloatBuffer storeFloats);
 
     native static boolean isGravityOverridden(long constraintVa);

src/main/java/com/github/stephengold/joltjni/VehicleConstraintRef.java

@@ -26,6 +26,7 @@ of this software and associated documentation files (the "Software"), to deal
 import com.github.stephengold.joltjni.readonly.ConstVehicleConstraint;
 import com.github.stephengold.joltjni.readonly.Vec3Arg;
 import com.github.stephengold.joltjni.template.Ref;
+import java.nio.DoubleBuffer;
 import java.nio.FloatBuffer;
 
 /**
@@ -378,6 +379,33 @@ public RMat44 getWheelWorldTransform(
         return result;
     }
 
+    /**
+     * Copy the world transform of the specified wheel. The constraint is
+     * unaffected.
+     *
+     * @param wheelIndex the index of the wheel to query (≥0)
+     * @param right the wheel's axis of rotation (a unit vector in the wheel's
+     * model space)
+     * @param up the "up" direction (a unit vector in the wheel's model space)
+     * @param storePosition storage for the translation component (not null,
+     * modified)
+     * @param storeRotation storage for the rotation component (not null,
+     * modified)
+     */
+    @Override
+    public void getWheelPositionAndRotation(int wheelIndex, Vec3Arg right,
+            Vec3Arg up, RVec3 storePosition, Quat storeRotation) {
+        long constraintVa = targetVa();
+        DoubleBuffer storeDoubles = Temporaries.doubleBuffer1.get();
+        FloatBuffer storeFloats = Temporaries.floatBuffer1.get();
+        right.copyTo(storeFloats);
+        up.copyTo(storeFloats, 3);
+        VehicleConstraint.getWheelWorldTransformComponents(
+                constraintVa, wheelIndex, storeDoubles, storeFloats);
+        storePosition.set(storeDoubles);
+        storeRotation.set(storeFloats);
+    }
+
     /**
      * Copy the "up" direction based on gravity. The constraint is unaffected.
      *

src/main/java/com/github/stephengold/joltjni/readonly/ConstVehicleConstraint.java

@@ -21,7 +21,9 @@ of this software and associated documentation files (the "Software"), to deal
  */
 package com.github.stephengold.joltjni.readonly;
 
+import com.github.stephengold.joltjni.Quat;
 import com.github.stephengold.joltjni.RMat44;
+import com.github.stephengold.joltjni.RVec3;
 import com.github.stephengold.joltjni.Vec3;
 import com.github.stephengold.joltjni.Wheel;
 
@@ -124,6 +126,22 @@ void getWheelLocalBasis(
     RMat44 getWheelWorldTransform(
             int wheelIndex, Vec3Arg right, Vec3Arg up);
 
+    /**
+     * Copy the world transform of the specified wheel. The constraint is
+     * unaffected.
+     *
+     * @param wheelIndex the index of the wheel to query (≥0)
+     * @param right the wheel's axis of rotation (a unit vector in the wheel's
+     * model space)
+     * @param up the "up" direction (a unit vector in the wheel's model space)
+     * @param storePosition storage for the translation component (not null,
+     * modified)
+     * @param storeRotation storage for the rotation component (not null,
+     * modified)
+     */
+    void getWheelPositionAndRotation(int wheelIndex, Vec3Arg right,
+            Vec3Arg up, RVec3 storePosition, Quat storeRotation);
+
     /**
      * Copy the "up" direction based on gravity. The constraint is unaffected.
      *

src/main/native/glue/v/VehicleConstraint.cpp

@@ -297,6 +297,35 @@ JNIEXPORT jlong JNICALL Java_com_github_stephengold_joltjni_VehicleConstraint_ge
     return reinterpret_cast<jlong> (pResult);
 }
 
+/*
+ * Class:     com_github_stephengold_joltjni_VehicleConstraint
+ * Method:    getWheelWorldTransformComponents
+ * Signature: (JILjava/nio/DoubleBuffer;Ljava/nio/FloatBuffer;)V
+ */
+JNIEXPORT void JNICALL Java_com_github_stephengold_joltjni_VehicleConstraint_getWheelWorldTransformComponents
+  (JNIEnv *pEnv, jclass, jlong constraintVa, jint wheelIndex,
+  jobject storeDoubles, jobject storeFloats) {
+    const VehicleConstraint * const pConstraint
+            = reinterpret_cast<VehicleConstraint *> (constraintVa);
+    DIRECT_DOUBLE_BUFFER(pEnv, storeDoubles, pDoubles, capacityDoubles);
+    JPH_ASSERT(capacityDoubles >= 3);
+    DIRECT_FLOAT_BUFFER(pEnv, storeFloats, pFloats, capacityFloats);
+    JPH_ASSERT(capacityFloats >= 6);
+    const Vec3 right(pFloats[0], pFloats[1], pFloats[2]);
+    const Vec3 up(pFloats[3], pFloats[4], pFloats[5]);
+    const RMat44 matrix
+            = pConstraint->GetWheelWorldTransform(wheelIndex, right, up);
+    const RVec3 position = matrix.GetTranslation();
+    pDoubles[0] = position.GetX();
+    pDoubles[1] = position.GetY();
+    pDoubles[2] = position.GetZ();
+    const Quat rotation = matrix.GetQuaternion();
+    pFloats[0] rotation.GetX();
+    pFloats[1] rotation.GetY();
+    pFloats[2] rotation.GetZ();
+    pFloats[3] rotation.GetW();
+}
+
 /*
  * Class:     com_github_stephengold_joltjni_VehicleConstraint
  * Method:    getWorldUp