fix(physics): reset velocity on move + update property so that joints break

core/src/objects/part.cpp

@@ -90,6 +90,11 @@ Part::Part(PartConstructParams params): Instance(&TYPE), cframe(Data::CFrame::Fr
                 .codec = cframeRotationCodec(),
                 .updateCallback = memberFunctionOf(&Part::onUpdated, this),
                 .flags = PropertyFlags::PROP_NOSAVE
+            }}, { "Velocity", {
+                .backingField = &velocity,
+                .type = &Vector3::TYPE,
+                .codec = fieldCodecOf<Data::Vector3>(),
+                .updateCallback = memberFunctionOf(&Part::onUpdated, this),
             }}, { "CFrame", {
                 .backingField = &cframe,
                 .type = &Data::CFrame::TYPE,
@@ -180,6 +185,10 @@ void Part::OnAncestryChanged(std::optional<std::shared_ptr<Instance>> child, std
 }
 
 void Part::onUpdated(std::string property) {
+    // Reset velocity
+    if (property != "Velocity")
+        velocity = Data::Vector3::ZERO;
+
     if (workspace())
         workspace().value()->SyncPartPhysics(std::dynamic_pointer_cast<Part>(this->shared_from_this()));
 

core/src/objects/part.h

@@ -43,6 +43,7 @@ protected:
 public:
     const static InstanceType TYPE;
 
+    Data::Vector3 velocity;
     Data::CFrame cframe;
     glm::vec3 size;
     Data::Color3 color;

core/src/objects/workspace.cpp

@@ -94,6 +94,7 @@ void Workspace::SyncPartPhysics(std::shared_ptr<Part> part) {
     part->rigidBody->updateMassFromColliders();
     part->rigidBody->updateLocalInertiaTensorFromColliders();
 
+    part->rigidBody->setLinearVelocity(part->velocity);
     // part->rigidBody->setMass(density * part->size.x * part->size.y * part->size.z);
 
     part->rigidBody->setUserData(&*part);
@@ -111,6 +112,7 @@ void Workspace::PhysicsStep(float deltaTime) {
         std::shared_ptr<Part> part = std::dynamic_pointer_cast<Part>(obj);
         const rp::Transform& transform = part->rigidBody->getTransform();
         part->cframe = Data::CFrame(transform);
+        part->velocity = part->rigidBody->getLinearVelocity();
     }
 }
 

editor/mainglwidget.cpp

@@ -157,6 +157,7 @@ void MainGLWidget::handleObjectDrag(QMouseEvent* evt) {
 
 
     gWorkspace()->SyncPartPhysics(draggingObject.lock());
+    draggingObject.lock()->UpdateProperty("Position");
     sendPropertyUpdatedSignal(draggingObject.lock(), "Position", draggingObject.lock()->position());
 }
 
@@ -244,6 +245,8 @@ void MainGLWidget::handleLinearTransform(QMouseEvent* evt) {
         playSound("./assets/excluded/switch.wav");
 
     gWorkspace()->SyncPartPhysics(part);
+    part->UpdateProperty("Position");
+    part->UpdateProperty("Size");
     sendPropertyUpdatedSignal(part, "Position", part->position());
     sendPropertyUpdatedSignal(part, "Size", Data::Vector3(part->size));
 }
@@ -287,6 +290,7 @@ void MainGLWidget::handleRotationalTransform(QMouseEvent* evt) {
     part->cframe = initialFrame * Data::CFrame::FromEulerAnglesXYZ(-angles);
 
     gWorkspace()->SyncPartPhysics(part);
+    part->UpdateProperty("Rotation");
     sendPropertyUpdatedSignal(part, "Rotation", part->cframe.ToEulerAnglesXYZ());
 }
 

editor/mainwindow.cpp

@@ -178,6 +178,8 @@ MainWindow::MainWindow(QWidget *parent)
 
     // gWorkspace()->AddChild(snap);
     gDataModel->GetService<JointsService>()->AddChild(snap);
+    snap->UpdateProperty("Part0");
+    snap->UpdateProperty("Part1");
 }
 
 void MainWindow::closeEvent(QCloseEvent* evt) {