fix: fixed a bug that would crash physics when rope joint lengths were below constraint tolerance, closes #1414

AlmasB · AlmasB · commit 73cf5645cd9d · 2025-04-28T20:57:46.000+01:00
diff --git a/fxgl-entity/src/main/java/com/almasb/fxgl/physics/box2d/dynamics/joints/RopeJoint.java b/fxgl-entity/src/main/java/com/almasb/fxgl/physics/box2d/dynamics/joints/RopeJoint.java
@@ -96,6 +96,9 @@ public void initVelocityConstraints(final SolverData data) {
             m_state = LimitState.INACTIVE;
         }
 
+        pool.pushRot(2);
+        pool.pushVec2(1);
+
         if (m_length > JBoxSettings.linearSlop) {
             m_u.mulLocal(1.0f / m_length);
         } else {
@@ -129,9 +132,6 @@ public void initVelocityConstraints(final SolverData data) {
             m_impulse = 0.0f;
         }
 
-        pool.pushRot(2);
-        pool.pushVec2(1);
-
         data.velocities[m_indexA].w = wA;
         data.velocities[m_indexB].w = wB;
     }

Original file line number	Diff line number	Diff line change
`@@ -96,6 +96,9 @@ public void initVelocityConstraints(final SolverData data) {`
`96`	`96`	`m_state = LimitState.INACTIVE;`
`97`	`97`	`}`
`98`	`98`
	`99`	`+ pool.pushRot(2);`
	`100`	`+ pool.pushVec2(1);`
	`101`	`+`
`99`	`102`	`if (m_length > JBoxSettings.linearSlop) {`
`100`	`103`	`m_u.mulLocal(1.0f / m_length);`
`101`	`104`	`} else {`
`@@ -129,9 +132,6 @@ public void initVelocityConstraints(final SolverData data) {`
`129`	`132`	`m_impulse = 0.0f;`
`130`	`133`	`}`
`131`	`134`
`132`		`- pool.pushRot(2);`
`133`		`- pool.pushVec2(1);`
`134`		`-`
`135`	`135`	`data.velocities[m_indexA].w = wA;`
`136`	`136`	`data.velocities[m_indexB].w = wB;`
`137`	`137`	`}`