First pass for getting things ready for grid snap button (#1118)

* first pass of change to simplify snapping for snap-to-grid button and fix snapping bug caused by non-uniform scale

Code/Framework/AzManipulatorTestFramework/Include/AzManipulatorTestFramework/AzManipulatorTestFrameworkUtils.h

@@ -12,17 +12,22 @@
 
 #pragma once
 
-#include <AzToolsFramework/Manipulators/ManipulatorManager.h>
-#include <AzToolsFramework/Manipulators/ManipulatorBus.h>
 #include <AzToolsFramework/Manipulators/LinearManipulator.h>
+#include <AzToolsFramework/Manipulators/ManipulatorBus.h>
+#include <AzToolsFramework/Manipulators/ManipulatorManager.h>
+#include <AzToolsFramework/Manipulators/PlanarManipulator.h>
 
 namespace AzManipulatorTestFramework
 {
-    //! Create a linear manipulator with a unit sphere bounds.
+    //! Create a linear manipulator with a unit sphere bound.
     AZStd::shared_ptr<AzToolsFramework::LinearManipulator> CreateLinearManipulator(
-        const AzToolsFramework::ManipulatorManagerId manipulatorManagerId,
-        const AZ::Vector3& position = AZ::Vector3::CreateZero(),
-        const float radius = 1.0f);
+        const AzToolsFramework::ManipulatorManagerId manipulatorManagerId, const AZ::Vector3& position = AZ::Vector3::CreateZero(),
+        float radius = 1.0f);
+
+    //! Create a planar manipulator with a unit sphere bound.
+    AZStd::shared_ptr<AzToolsFramework::PlanarManipulator> CreatePlanarManipulator(
+        const AzToolsFramework::ManipulatorManagerId manipulatorManagerId, const AZ::Vector3& position = AZ::Vector3::CreateZero(),
+        float radius = 1.0f);
 
     //! Create a mouse pick from the specified ray and screen point.
     AzToolsFramework::ViewportInteraction::MousePick CreateMousePick(
@@ -34,14 +39,12 @@ namespace AzManipulatorTestFramework
 
     //! Create a mouse interaction from the specified pick, buttons, interaction id and keyboard modifiers.
     AzToolsFramework::ViewportInteraction::MouseInteraction CreateMouseInteraction(
-        const AzToolsFramework::ViewportInteraction::MousePick& mousePick,
-        AzToolsFramework::ViewportInteraction::MouseButtons buttons,
+        const AzToolsFramework::ViewportInteraction::MousePick& mousePick, AzToolsFramework::ViewportInteraction::MouseButtons buttons,
         AzToolsFramework::ViewportInteraction::InteractionId interactionId,
         AzToolsFramework::ViewportInteraction::KeyboardModifiers modifiers);
 
     //! Create a mouse buttons from the specified mouse button.
-    AzToolsFramework::ViewportInteraction::MouseButtons CreateMouseButtons(
-        AzToolsFramework::ViewportInteraction::MouseButton button);
+    AzToolsFramework::ViewportInteraction::MouseButtons CreateMouseButtons(AzToolsFramework::ViewportInteraction::MouseButton button);
 
     //! Create a mouse interaction event from the specified interaction and event.
     AzToolsFramework::ViewportInteraction::MouseInteractionEvent CreateMouseInteractionEvent(
@@ -61,5 +64,5 @@ namespace AzManipulatorTestFramework
     AzFramework::ScreenPoint GetCameraStateViewportCenter(const AzFramework::CameraState& cameraState);
 
     //! Default viewport size (1080p) in 16:9 aspect ratio.
-    const auto DefaultViewportSize = AZ::Vector2(1920.0f, 1080.0f);
+    inline const auto DefaultViewportSize = AZ::Vector2(1920.0f, 1080.0f);
 } // namespace AzManipulatorTestFramework

Code/Framework/AzManipulatorTestFramework/Source/AzManipulatorTestFrameworkUtils.cpp

@@ -14,7 +14,6 @@
 #include <AzFramework/Viewport/ViewportScreen.h>
 #include <AzManipulatorTestFramework/AzManipulatorTestFrameworkUtils.h>
 #include <AzToolsFramework/ViewportSelection/EditorInteractionSystemViewportSelectionRequestBus.h>
-#include <AzToolsFramework/ViewportSelection/EditorInteractionSystemViewportSelectionRequestBus.h>
 #include <AzToolsFramework/ViewportSelection/EditorTransformComponentSelectionRequestBus.h>
 
 namespace AzManipulatorTestFramework
@@ -28,22 +27,21 @@ namespace AzManipulatorTestFramework
     using MouseEvent = AzToolsFramework::ViewportInteraction::MouseEvent;
     using MousePick = AzToolsFramework::ViewportInteraction::MousePick;
 
-    AZStd::shared_ptr<AzToolsFramework::LinearManipulator> CreateLinearManipulator(
-        const AzToolsFramework::ManipulatorManagerId manipulatorManagerId,
-        const AZ::Vector3& position,
-        const float radius)
+    // create a default sphere view for a manipulator for simple intersection
+    template<typename Manipulator>
+    void SetupManipulatorView(
+        AZStd::shared_ptr<Manipulator> manipulator, const AzToolsFramework::ManipulatorManagerId manipulatorManagerId,
+        const AZ::Vector3& position, const float radius)
     {
-        auto manipulator = AzToolsFramework::LinearManipulator::MakeShared(AZ::Transform::CreateIdentity());
-        manipulator->SetLocalPosition(position);
-
         // unit sphere view
         auto sphereView = AzToolsFramework::CreateManipulatorViewSphere(
             AZ::Colors::Red, radius,
-            [](const MouseInteraction& /*mouseInteraction*/, const bool /*mouseOver*/,
-                const AZ::Color& defaultColor)
-        {
-            return defaultColor;
-        }, true);
+            []([[maybe_unused]] const MouseInteraction& mouseInteraction, [[maybe_unused]] const bool mouseOver,
+               const AZ::Color& defaultColor)
+            {
+                return defaultColor;
+            },
+            true);
 
         // unit sphere bound
         AzToolsFramework::Picking::BoundShapeSphere sphereBound;
@@ -62,6 +60,26 @@ namespace AzManipulatorTestFramework
         // this would occur internally when the manipulator is drawn but we must do manually here to ensure that the
         // bounds will always be valid upon instantiation
         view->RefreshBound(manipulatorManagerId, manipulator->GetManipulatorId(), sphereBound);
+    }
+
+    AZStd::shared_ptr<AzToolsFramework::LinearManipulator> CreateLinearManipulator(
+        const AzToolsFramework::ManipulatorManagerId manipulatorManagerId, const AZ::Vector3& position, const float radius)
+    {
+        auto manipulator = AzToolsFramework::LinearManipulator::MakeShared(AZ::Transform::CreateIdentity());
+        manipulator->SetLocalPosition(position);
+
+        SetupManipulatorView(manipulator, manipulatorManagerId, position, radius);
+
+        return manipulator;
+    }
+
+    AZStd::shared_ptr<AzToolsFramework::PlanarManipulator> CreatePlanarManipulator(
+        const AzToolsFramework::ManipulatorManagerId manipulatorManagerId, const AZ::Vector3& position, const float radius)
+    {
+        auto manipulator = AzToolsFramework::PlanarManipulator::MakeShared(AZ::Transform::CreateIdentity());
+        manipulator->SetLocalPosition(position);
+
+        SetupManipulatorView(manipulator, manipulatorManagerId, position, radius);
 
         return manipulator;
     }
@@ -104,8 +122,7 @@ namespace AzManipulatorTestFramework
         return buttons;
     }
 
-    MouseInteractionEvent CreateMouseInteractionEvent(
-        const MouseInteraction& mouseInteraction, MouseEvent event)
+    MouseInteractionEvent CreateMouseInteractionEvent(const MouseInteraction& mouseInteraction, MouseEvent event)
     {
         return MouseInteractionEvent(mouseInteraction, event);
     }
@@ -114,8 +131,7 @@ namespace AzManipulatorTestFramework
     {
         AzToolsFramework::EditorInteractionSystemViewportSelectionRequestBus::Event(
             AzToolsFramework::GetEntityContextId(),
-            &AzToolsFramework::ViewportInteraction::InternalMouseViewportRequests::InternalHandleAllMouseInteractions,
-            event);
+            &AzToolsFramework::ViewportInteraction::InternalMouseViewportRequests::InternalHandleAllMouseInteractions, event);
     }
 
     AzFramework::CameraState SetCameraStatePosition(const AZ::Vector3& position, AzFramework::CameraState& cameraState)
@@ -133,9 +149,7 @@ namespace AzManipulatorTestFramework
 
     AzFramework::ScreenPoint GetCameraStateViewportCenter(const AzFramework::CameraState& cameraState)
     {
-        return {
-            aznumeric_cast<int>(cameraState.m_viewportSize.GetX() / 2.f),
-            aznumeric_cast<int>(cameraState.m_viewportSize.GetY() / 2.f)
-        };
+        return { aznumeric_cast<int>(cameraState.m_viewportSize.GetX() / 2.f),
+                 aznumeric_cast<int>(cameraState.m_viewportSize.GetY() / 2.f) };
     }
-} // namespace UnitTest
+} // namespace AzManipulatorTestFramework

Code/Framework/AzManipulatorTestFramework/Tests/GridSnappingTest.cpp

@@ -10,52 +10,55 @@
  *
  */
 
+#include "AzManipulatorTestFrameworkTestFixtures.h"
+
 #include <AzCore/std/smart_ptr/unique_ptr.h>
 #include <AzFramework/Viewport/ViewportScreen.h>
 #include <AzManipulatorTestFramework/AzManipulatorTestFramework.h>
-#include "AzManipulatorTestFrameworkTestFixtures.h"
-#include <AzManipulatorTestFramework/DirectManipulatorViewportInteraction.h>
-#include <AzManipulatorTestFramework/IndirectManipulatorViewportInteraction.h>
-#include <AzManipulatorTestFramework/ImmediateModeActionDispatcher.h>
 #include <AzManipulatorTestFramework/AzManipulatorTestFrameworkUtils.h>
+#include <AzManipulatorTestFramework/DirectManipulatorViewportInteraction.h>
+#include <AzManipulatorTestFramework/ImmediateModeActionDispatcher.h>
+#include <AzManipulatorTestFramework/IndirectManipulatorViewportInteraction.h>
+#include <AzToolsFramework/Manipulators/LinearManipulator.h>
+#include <AzToolsFramework/Manipulators/PlanarManipulator.h>
 #include <AzToolsFramework/ViewportSelection/EditorSelectionUtil.h>
+#include <AZTestShared/Math/MathTestHelpers.h>
 
 namespace UnitTest
 {
-    class GridSnappingFixture
-        : public ToolsApplicationFixture
+    class GridSnappingFixture : public ToolsApplicationFixture
     {
     public:
         GridSnappingFixture()
             : m_viewportManipulatorInteraction(AZStd::make_unique<AzManipulatorTestFramework::DirectCallManipulatorViewportInteraction>())
-            , m_actionDispatcher(AZStd::make_unique<AzManipulatorTestFramework::ImmediateModeActionDispatcher>(*m_viewportManipulatorInteraction))
-            , m_linearManipulator(
-                AzManipulatorTestFramework::CreateLinearManipulator(
-                    m_viewportManipulatorInteraction->GetManipulatorManager().GetId(),
-                    /*position=*/AZ::Vector3(0.0f, 50.0f, 0.0f),
-                    /*radius=*/m_boundsRadius))
-        {}
+            , m_actionDispatcher(
+                  AZStd::make_unique<AzManipulatorTestFramework::ImmediateModeActionDispatcher>(*m_viewportManipulatorInteraction))
+        {
+        }
 
     protected:
         void SetUpEditorFixtureImpl() override
         {
-            m_cameraState = AzFramework::CreateIdentityDefaultCamera(
-                AZ::Vector3::CreateZero(), AzManipulatorTestFramework::DefaultViewportSize);
+            m_cameraState =
+                AzFramework::CreateIdentityDefaultCamera(AZ::Vector3::CreateZero(), AzManipulatorTestFramework::DefaultViewportSize);
         }
 
     public:
-
         const float m_boundsRadius = 1.0f;
         AZStd::unique_ptr<AzManipulatorTestFramework::ManipulatorViewportInteraction> m_viewportManipulatorInteraction;
         AZStd::unique_ptr<AzManipulatorTestFramework::ImmediateModeActionDispatcher> m_actionDispatcher;
-        AZStd::shared_ptr<AzToolsFramework::LinearManipulator> m_linearManipulator;
         AzFramework::CameraState m_cameraState;
     };
 
     TEST_F(GridSnappingFixture, MouseDownWithSnappingEnabledSnapsToClosestGridSize)
     {
+        AZStd::shared_ptr<AzToolsFramework::LinearManipulator> linearManipulator(AzManipulatorTestFramework::CreateLinearManipulator(
+            m_viewportManipulatorInteraction->GetManipulatorManager().GetId(),
+            /*position=*/AZ::Vector3(0.0f, 50.0f, 0.0f),
+            /*radius=*/m_boundsRadius));
+
         // the initial starting position of the manipulator (in front of the camera)
-        const auto initialPositionWorld = m_linearManipulator->GetLocalPosition();
+        const auto initialPositionWorld = linearManipulator->GetLocalPosition();
         // where the manipulator should end up (in front and to the left of the camera)
         const auto finalPositionWorld = AZ::Vector3(-10.0f, 50.0f, 0.0f);
         // perspective scale factor for manipulator distance to camera
@@ -66,21 +69,18 @@ namespace UnitTest
         // adjusted final world position taking into account the manipulator position relative to the camera
         const auto finalPositionWorldAdjusted = finalPositionWorld - (vectorToInitialPositionWorld * scaledRadiusBound);
         // calculate the position in screen space of the initial position of the manipulator
-        const auto initialPositionScreen =
-            AzFramework::WorldToScreen(initialPositionWorld, m_cameraState);
+        const auto initialPositionScreen = AzFramework::WorldToScreen(initialPositionWorld, m_cameraState);
         // calculate the position in screen space of the final position of the manipulator
         const auto finalPositionScreen = AzFramework::WorldToScreen(finalPositionWorldAdjusted, m_cameraState);
 
         // callback to update the manipulator's current position
-        m_linearManipulator->InstallMouseMoveCallback(
-            [this](const AzToolsFramework::LinearManipulator::Action& action)
-        {
-            auto pos = action.LocalPosition();
-            m_linearManipulator->SetLocalPosition(pos);
-        });
+        linearManipulator->InstallMouseMoveCallback(
+            [this, linearManipulator](const AzToolsFramework::LinearManipulator::Action& action)
+            {
+                linearManipulator->SetLocalPosition(action.LocalPosition());
+            });
 
-        m_actionDispatcher
-            ->EnableSnapToGrid()
+        m_actionDispatcher->EnableSnapToGrid()
             ->GridSize(5.0f)
             ->CameraState(m_cameraState)
             ->MousePosition(initialPositionScreen)
@@ -89,7 +89,67 @@ namespace UnitTest
             ->MousePosition(finalPositionScreen)
             ->MouseLButtonUp()
             ->ExpectManipulatorNotBeingInteracted()
-            ->ExpectTrue(m_linearManipulator->GetLocalPosition().IsClose(finalPositionWorld, 0.01f))
-            ;
+            ->ExpectTrue(linearManipulator->GetLocalPosition().IsClose(finalPositionWorld, 0.01f));
+    }
+
+    template<typename Manipulator>
+    void ValidateManipulatorSnappingBehavior(
+        AZStd::shared_ptr<Manipulator> manipulator, AzManipulatorTestFramework::ImmediateModeActionDispatcher* actionDispatcher,
+        const AzFramework::CameraState& cameraState)
+    {
+        manipulator->SetLocalOrientation(AZ::Quaternion::CreateFromEulerAnglesDegrees(AZ::Vector3(180.0f, 0.0f, 135.0f)));
+
+        // the initial starting position of the manipulator (in front of the camera)
+        const auto initialPositionWorld = manipulator->GetLocalPosition() + AZ::Vector3::CreateAxisX(0.15f);
+        // where the manipulator should end up (unmoved)
+        const auto finalPositionWorld = manipulator->GetLocalPosition();
+        // where we should move the mouse to
+        const auto attemptPositionWorld = manipulator->GetLocalPosition() + AZ::Vector3::CreateAxisX(0.35f);
+        // calculate the position in screen space of the initial position of the manipulator
+        const auto initialPositionScreen = AzFramework::WorldToScreen(initialPositionWorld, cameraState);
+        // calculate the position in screen space of the final position of the manipulator
+        const auto attemptPositionScreen = AzFramework::WorldToScreen(attemptPositionWorld, cameraState);
+
+        // callback to update the manipulator's current position
+        manipulator->InstallMouseMoveCallback(
+            [manipulator](const typename Manipulator::Action& action)
+            {
+                manipulator->SetLocalPosition(action.LocalPosition());
+            });
+
+        actionDispatcher->EnableSnapToGrid()
+            ->GridSize(1.0f)
+            ->CameraState(cameraState)
+            ->MousePosition(initialPositionScreen)
+            ->MouseLButtonDown()
+            ->ExpectManipulatorBeingInteracted()
+            ->MousePosition(attemptPositionScreen)
+            ->MouseLButtonUp()
+            ->ExpectManipulatorNotBeingInteracted()
+            ->ExpectThat(manipulator->GetLocalPosition(), IsCloseTolerance(finalPositionWorld, 0.01f));
+    }
+
+    TEST_F(GridSnappingFixture, MouseDownAndMoveLinearManipulatorDoesNotSnapWithMovementSmallerThanHalfGridSize)
+    {
+        AZStd::shared_ptr<AzToolsFramework::LinearManipulator> linearManipulator(AzManipulatorTestFramework::CreateLinearManipulator(
+            m_viewportManipulatorInteraction->GetManipulatorManager().GetId(),
+            /*position=*/AZ::Vector3(0.0f, 10.0f, 0.0f),
+            /*radius=*/m_boundsRadius));
+
+        linearManipulator->SetAxis(AZ::Vector3::CreateAxisY());
+
+        ValidateManipulatorSnappingBehavior(linearManipulator, m_actionDispatcher.get(), m_cameraState);
+    }
+
+    TEST_F(GridSnappingFixture, MouseDownAndMovePlanarManipulatorDoesNotSnapWithMovementSmallerThanHalfGridSize)
+    {
+        AZStd::shared_ptr<AzToolsFramework::PlanarManipulator> planarManipulator(AzManipulatorTestFramework::CreatePlanarManipulator(
+            m_viewportManipulatorInteraction->GetManipulatorManager().GetId(),
+            /*position=*/AZ::Vector3(0.0f, 10.0f, 0.0f),
+            /*radius=*/m_boundsRadius));
+
+        planarManipulator->SetAxes(AZ::Vector3::CreateAxisY(), AZ::Vector3::CreateAxisZ());
+
+        ValidateManipulatorSnappingBehavior(planarManipulator, m_actionDispatcher.get(), m_cameraState);
     }
 } // namespace UnitTest

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/BaseManipulator.cpp

@@ -433,6 +433,11 @@ namespace AzToolsFramework
         return m_manipulatorSpaceWithLocalTransform.GetSpace();
     }
 
+    const AZ::Vector3& Manipulators::GetNonUniformScale() const
+    {
+        return m_manipulatorSpaceWithLocalTransform.GetNonUniformScale();
+    }
+
     void Manipulators::SetSpace(const AZ::Transform& worldFromLocal)
     {
         m_manipulatorSpaceWithLocalTransform.SetSpace(worldFromLocal);

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/EditorVertexSelection.cpp

@@ -192,8 +192,7 @@ namespace AzToolsFramework
     /// for each vertex associated with the translation manipulator to use with offset calculations when updating.
     template<typename Vertex>
     void InitializeVertexLookup(
-        IndexedTranslationManipulator<Vertex>& translationManipulator,
-        const AZ::EntityId entityId, const AZ::Vector3& snapOffset)
+        IndexedTranslationManipulator<Vertex>& translationManipulator, const AZ::EntityId entityId)
     {
         AZ_PROFILE_FUNCTION(AZ::Debug::ProfileCategory::AzToolsFramework);
 
@@ -202,7 +201,7 @@ namespace AzToolsFramework
         AZ::FixedVerticesRequestBus<Vertex>::Bind(fixedVertices, entityId);
 
         translationManipulator.Process(
-            [snapOffset, fixedVertices]
+            [fixedVertices]
             (typename IndexedTranslationManipulator<Vertex>::VertexLookup& vertexLookup)
         {
             Vertex vertex;
@@ -213,7 +212,7 @@ namespace AzToolsFramework
 
             if (found)
             {
-                vertexLookup.m_start = vertex + AZ::AdaptVertexIn<Vertex>(snapOffset);
+                vertexLookup.m_start = vertex;
                 vertexLookup.m_offset = Vertex::CreateZero();
             }
         });
@@ -250,10 +249,10 @@ namespace AzToolsFramework
 
         // linear manipulator callbacks
         m_translationManipulator->m_manipulator.InstallLinearManipulatorMouseDownCallback(
-            [this](const LinearManipulator::Action& action)
+            [this]([[maybe_unused]] const LinearManipulator::Action& action)
         {
             BeginBatchMovement();
-            InitializeVertexLookup(*m_translationManipulator, GetEntityId(), action.m_start.m_positionSnapOffset);
+            InitializeVertexLookup(*m_translationManipulator, GetEntityId());
         });
 
         m_translationManipulator->m_manipulator.InstallLinearManipulatorMouseMoveCallback(
@@ -264,17 +263,17 @@ namespace AzToolsFramework
         });
 
         m_translationManipulator->m_manipulator.InstallLinearManipulatorMouseUpCallback(
-            [this](const LinearManipulator::Action& /*action*/)
+            [this]([[maybe_unused]] const LinearManipulator::Action& action)
         {
             EndBatchMovement();
         });
 
         // planar manipulator callbacks
         m_translationManipulator->m_manipulator.InstallPlanarManipulatorMouseDownCallback(
-            [this](const PlanarManipulator::Action& action)
+            [this]([[maybe_unused]] const PlanarManipulator::Action& action)
         {
             BeginBatchMovement();
-            InitializeVertexLookup(*m_translationManipulator, GetEntityId(), action.m_start.m_snapOffset);
+            InitializeVertexLookup(*m_translationManipulator, GetEntityId());
         });
 
         m_translationManipulator->m_manipulator.InstallPlanarManipulatorMouseMoveCallback(
@@ -285,17 +284,17 @@ namespace AzToolsFramework
         });
 
         m_translationManipulator->m_manipulator.InstallPlanarManipulatorMouseUpCallback(
-            [this](const PlanarManipulator::Action& /*action*/)
+            [this]([[maybe_unused]] const PlanarManipulator::Action& action)
         {
             EndBatchMovement();
         });
 
         // surface manipulator callbacks
         m_translationManipulator->m_manipulator.InstallSurfaceManipulatorMouseDownCallback(
-            [this](const SurfaceManipulator::Action& action)
+            [this]([[maybe_unused]] const SurfaceManipulator::Action& action)
         {
             BeginBatchMovement();
-            InitializeVertexLookup(*m_translationManipulator, GetEntityId(), action.m_start.m_snapOffset);
+            InitializeVertexLookup(*m_translationManipulator, GetEntityId());
         });
 
         m_translationManipulator->m_manipulator.InstallSurfaceManipulatorMouseMoveCallback(
@@ -306,7 +305,7 @@ namespace AzToolsFramework
         });
 
         m_translationManipulator->m_manipulator.InstallSurfaceManipulatorMouseUpCallback(
-            [this](const SurfaceManipulator::Action& /*action*/)
+            [this]([[maybe_unused]] const SurfaceManipulator::Action& action)
         {
             EndBatchMovement();
         });
@@ -893,7 +892,7 @@ namespace AzToolsFramework
         {
             BeginBatchMovement();
 
-            InitializeVertexLookup(*m_translationManipulator, GetEntityId(), AZ::Vector3::CreateZero());
+            InitializeVertexLookup(*m_translationManipulator, GetEntityId());
             // note: AdaptVertexIn/Out is to ensure we clamp the vertex local Z position to 0 if
             // dealing with Vector2s when setting the position of the manipulator.
             const AZ::Vector3 localOffset =

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/LinearManipulator.cpp

@@ -23,8 +23,8 @@ namespace AzToolsFramework
 {
     LinearManipulator::Starter CalculateLinearManipulationDataStart(
         const LinearManipulator::Fixed& fixed, const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale,
-        const AZ::Transform& localTransform, const GridSnapAction& gridSnapAction, const ViewportInteraction::MouseInteraction& interaction,
-        const float intersectionDistance, const AzFramework::CameraState& cameraState)
+        const AZ::Transform& localTransform, const ViewportInteraction::MouseInteraction& interaction, const float intersectionDistance,
+        const AzFramework::CameraState& cameraState)
     {
         const ManipulatorInteraction manipulatorInteraction =
             BuildManipulatorInteraction(
@@ -50,28 +50,9 @@ namespace AzToolsFramework
             manipulatorInteraction.m_localRayOrigin, manipulatorInteraction.m_localRayDirection,
             localIntersectionPoint, startTransition.m_localNormal, start.m_localHitPosition);
 
-        const float gridSize = gridSnapAction.m_gridSnapParams.m_gridSize;
-        const bool snapping = gridSnapAction.m_gridSnapParams.m_gridSnap;
-        const float scaleRecip = manipulatorInteraction.m_scaleReciprocal;
-
-        // calculate position amount to snap, to align with grid
-        const AZ::Vector3 positionSnapOffset = snapping && !gridSnapAction.m_localSnapping
-            ? CalculateSnappedOffset(localTransform.GetTranslation(), axis, gridSize * scaleRecip)
-            : AZ::Vector3::CreateZero();
-
-        const AZ::Vector3 localScale = AZ::Vector3(localTransform.GetUniformScale());
-        const AZ::Quaternion localRotation = QuaternionFromTransformNoScaling(localTransform);
-        // calculate scale amount to snap, to align to round scale value
-        const AZ::Vector3 scaleSnapOffset = snapping && !gridSnapAction.m_localSnapping
-            ? localRotation.GetInverseFull().TransformVector(CalculateSnappedOffset(
-                localRotation.TransformVector(localScale), axis, gridSize * scaleRecip))
-            : AZ::Vector3::CreateZero();
-
         start.m_screenPosition = interaction.m_mousePick.m_screenCoordinates;
-        start.m_positionSnapOffset = positionSnapOffset;
-        start.m_scaleSnapOffset = scaleSnapOffset;
-        start.m_localPosition = localTransform.GetTranslation() + positionSnapOffset;
-        start.m_localScale = localScale + scaleSnapOffset;
+        start.m_localPosition = localTransform.GetTranslation();
+        start.m_localScale = AZ::Vector3(localTransform.GetUniformScale());;
         start.m_localAxis = axis;
         // sign to determine which side of the linear axis we pressed
         // (useful to know when the visual axis flips to face the camera)
@@ -87,7 +68,7 @@ namespace AzToolsFramework
     LinearManipulator::Action CalculateLinearManipulationDataAction(
         const LinearManipulator::Fixed& fixed, const LinearManipulator::Starter& starter,
         const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale, const AZ::Transform& localTransform,
-        const GridSnapAction& gridSnapAction, const ViewportInteraction::MouseInteraction& interaction)
+        const GridSnapParameters& gridSnapParams, const ViewportInteraction::MouseInteraction& interaction)
     {
         const ManipulatorInteraction manipulatorInteraction =
             BuildManipulatorInteraction(
@@ -108,31 +89,34 @@ namespace AzToolsFramework
             GetCameraState(interaction.m_interactionId.m_viewportId));
 
         const AZ::Vector3 axis = TransformDirectionNoScaling(localTransform, fixed.m_axis);
-        // The local positions have been transformed to the reference frame of the object being manipulated. But they appear in the world
-        // with non-uniform scale applied, and the object being manipulated will want to work with unscaled deltas, so we need to divide by
-        // the non-uniform scale here.
+        // the local positions have been transformed to the reference frame of the object being manipulated, but they appear in the world
+        // with non-uniform scale applied, the object being manipulated will want to work with unscaled deltas, so we need to divide by
+        // the non-uniform scale here
         const AZ::Vector3 hitDelta = (localHitPosition - start.m_localHitPosition) / nonUniformScale;
         const AZ::Vector3 unsnappedOffset = axis * axis.Dot(hitDelta);
 
-        const float scaleRecip = manipulatorInteraction.m_scaleReciprocal * axis.Dot(manipulatorInteraction.m_nonUniformScaleReciprocal);
-        const float gridSize = gridSnapAction.m_gridSnapParams.m_gridSize;
-        const bool snapping = gridSnapAction.m_gridSnapParams.m_gridSnap;
+        const float scaleRecip =
+            manipulatorInteraction.m_scaleReciprocal * fixed.m_axis.Dot(manipulatorInteraction.m_nonUniformScaleReciprocal);
+        const float gridSize = gridSnapParams.m_gridSize;
+        const bool snapping = gridSnapParams.m_gridSnap;
 
         LinearManipulator::Action action;
         action.m_fixed = fixed;
         action.m_start = start;
         action.m_current.m_localPositionOffset = snapping
-            ? unsnappedOffset + CalculateSnappedOffset(unsnappedOffset, axis, gridSize * scaleRecip)
+            ? CalculateSnappedAmount(unsnappedOffset, axis, gridSize * scaleRecip)
             : unsnappedOffset;
         action.m_current.m_screenPosition = interaction.m_mousePick.m_screenCoordinates;
         action.m_viewportId = interaction.m_interactionId.m_viewportId;
 
         const AZ::Quaternion localRotation = QuaternionFromTransformNoScaling(localTransform);
-        const AZ::Vector3 scaledUnsnappedOffset = unsnappedOffset * startTransition.m_screenToWorldScale * NonUniformScaleReciprocal(nonUniformScale);
+        const AZ::Vector3 scaledUnsnappedOffset =
+            unsnappedOffset * startTransition.m_screenToWorldScale * NonUniformScaleReciprocal(nonUniformScale);
+
         // how much to adjust the scale based on movement
         const AZ::Quaternion invLocalRotation = localRotation.GetInverseFull();
         action.m_current.m_localScaleOffset = snapping
-            ? invLocalRotation.TransformVector((scaledUnsnappedOffset + CalculateSnappedOffset(scaledUnsnappedOffset, axis, gridSize * scaleRecip)))
+            ? invLocalRotation.TransformVector(CalculateSnappedAmount(scaledUnsnappedOffset, axis, gridSize * scaleRecip))
             : invLocalRotation.TransformVector(scaledUnsnappedOffset);
 
         // record what modifier keys are held during this action
@@ -171,19 +155,18 @@ namespace AzToolsFramework
         const ViewportInteraction::MouseInteraction& interaction, const float rayIntersectionDistance)
     {
         const AZ::Transform worldFromLocalUniformScale = TransformUniformScale(GetSpace());
-        const GridSnapParameters gridSnapParams = GridSnapSettings(interaction.m_interactionId.m_viewportId);
 
         // note: m_localTransform must not be made uniform as it may contain a local scale we want to snap
         m_starter = CalculateLinearManipulationDataStart(
-            m_fixed, worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(),
-            GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()), interaction, rayIntersectionDistance,
+            m_fixed, worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(), interaction, rayIntersectionDistance,
             GetCameraState(interaction.m_interactionId.m_viewportId));
 
         if (m_onLeftMouseDownCallback)
         {
+            const GridSnapParameters gridSnapParams = GridSnapSettings(interaction.m_interactionId.m_viewportId);
+
             m_onLeftMouseDownCallback(CalculateLinearManipulationDataAction(
-                m_fixed, m_starter, worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(),
-                GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()), interaction));
+                m_fixed, m_starter, worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(), gridSnapParams, interaction));
         }
     }
 
@@ -195,8 +178,8 @@ namespace AzToolsFramework
 
             // note: m_localTransform must not be made uniform as it may contain a local scale we want to snap
             m_onMouseMoveCallback(CalculateLinearManipulationDataAction(
-                m_fixed, m_starter, TransformUniformScale(GetSpace()), GetNonUniformScale(), GetLocalTransform(),
-                GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()), interaction));
+                m_fixed, m_starter, TransformUniformScale(GetSpace()), GetNonUniformScale(), GetLocalTransform(), gridSnapParams,
+                interaction));
         }
     }
 
@@ -208,8 +191,7 @@ namespace AzToolsFramework
 
             // note: m_localTransform must not be made uniform as it may contain a local scale we want to snap
             m_onLeftMouseUpCallback(CalculateLinearManipulationDataAction(
-                m_fixed, m_starter, TransformUniformScale(GetSpace()), GetNonUniformScale(), GetLocalTransform(),
-                GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()), interaction));
+                m_fixed, m_starter, TransformUniformScale(GetSpace()), GetNonUniformScale(), GetLocalTransform(), gridSnapParams, interaction));
         }
     }
 
@@ -232,8 +214,8 @@ namespace AzToolsFramework
                     GridSnapSettings(mouseInteraction.m_interactionId.m_viewportId);
 
                 const auto action = CalculateLinearManipulationDataAction(
-                    m_fixed, m_starter, TransformUniformScale(GetSpace()), GetNonUniformScale(), GetLocalTransform(),
-                    GridSnapAction(gridSnapParams, mouseInteraction.m_keyboardModifiers.Alt()), mouseInteraction);
+                    m_fixed, m_starter, TransformUniformScale(GetSpace()), GetNonUniformScale(), GetLocalTransform(), gridSnapParams,
+                    mouseInteraction);
 
                 // display the exact hit (ray intersection) of the mouse pick on the manipulator
                 DrawTransformAxes(

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/LinearManipulator.h

@@ -20,7 +20,7 @@
 
 namespace AzToolsFramework
 {
-    struct GridSnapAction;
+    struct GridSnapParameters;
 
     /// LinearManipulator serves as a visual tool for users to modify values
     /// in one dimension on an axis defined in 3D space.
@@ -68,8 +68,6 @@ namespace AzToolsFramework
             AZ::Vector3 m_localScale; ///< The current scale of the manipulator in local space.
             AZ::Vector3 m_localHitPosition; ///< The intersection point in local space between the ray and the manipulator when the mouse down event happens.
             AZ::Vector3 m_localAxis; ///< The axis in the local space of the manipulator itself.
-            AZ::Vector3 m_positionSnapOffset; ///< The snap offset amount to ensure manipulator is aligned to the grid.
-            AZ::Vector3 m_scaleSnapOffset; ///< The snap offset amount to ensure manipulator is aligned to round scale increments.
             float m_sign; ///< Used to determine which side of the axis we clicked on in case it's flipped to face the camera.
             AzFramework::ScreenPoint m_screenPosition; ///< The initial position in screen space of the manipulator.
         };
@@ -91,7 +89,7 @@ namespace AzToolsFramework
             ViewportInteraction::KeyboardModifiers m_modifiers;
             int m_viewportId; ///< The id of the viewport this manipulator is being used in.
             AZ::Vector3 LocalScale() const { return m_start.m_localScale + m_current.m_localScaleOffset; }
-            AZ::Vector3 LocalScaleOffset() const { return m_start.m_scaleSnapOffset + m_current.m_localScaleOffset; }
+            AZ::Vector3 LocalScaleOffset() const { return m_current.m_localScaleOffset; }
             AZ::Vector3 LocalPosition() const { return m_start.m_localPosition + m_current.m_localPositionOffset; }
             AZ::Vector3 LocalPositionOffset() const { return m_current.m_localPositionOffset; }
             AZ::Vector2 ScreenOffset() const
@@ -162,11 +160,11 @@ namespace AzToolsFramework
 
     LinearManipulator::Starter CalculateLinearManipulationDataStart(
         const LinearManipulator::Fixed& fixed, const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale,
-        const AZ::Transform& localTransform, const GridSnapAction& gridSnapAction, const ViewportInteraction::MouseInteraction& interaction,
-        float intersectionDistance, const AzFramework::CameraState& cameraState);
+        const AZ::Transform& localTransform, const ViewportInteraction::MouseInteraction& interaction, float intersectionDistance,
+        const AzFramework::CameraState& cameraState);
 
     LinearManipulator::Action CalculateLinearManipulationDataAction(
         const LinearManipulator::Fixed& fixed, const LinearManipulator::Starter& starter,
         const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale, const AZ::Transform& localTransform,
-        const GridSnapAction& gridSnapAction, const ViewportInteraction::MouseInteraction& interaction);
+        const GridSnapParameters& gridSnapParams, const ViewportInteraction::MouseInteraction& interaction);
 } // namespace AzToolsFramework

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/ManipulatorSnapping.cpp

@@ -42,12 +42,6 @@ namespace AzToolsFramework
     {
     }
 
-    GridSnapAction::GridSnapAction(const GridSnapParameters& gridSnapParameters, const bool localSnapping)
-        : m_gridSnapParams(gridSnapParameters)
-        , m_localSnapping(localSnapping)
-    {
-    }
-
     ManipulatorInteraction BuildManipulatorInteraction(
         const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale,
         const AZ::Vector3& worldRayOrigin, const AZ::Vector3& worldRayDirection)
@@ -57,19 +51,39 @@ namespace AzToolsFramework
 
         return {localFromWorldUniform.TransformPoint(worldRayOrigin),
                 TransformDirectionNoScaling(localFromWorldUniform, worldRayDirection),
-                ScaleReciprocal(worldFromLocalUniform),
-                NonUniformScaleReciprocal(nonUniformScale)};
+                NonUniformScaleReciprocal(nonUniformScale),
+                ScaleReciprocal(worldFromLocalUniform)};
     }
 
-    AZ::Vector3 CalculateSnappedOffset(
-        const AZ::Vector3& unsnappedPosition, const AZ::Vector3& axis, const float size)
+    struct SnapAdjustment
+    {
+        float m_existingSnapDistance; //!< How far to snap up or down to align to the grid.
+        float m_nextSnapDistance; //!< The snap increment (will return full signed value (grid size) when distance
+                                  //!< moved is greater than half of the grid size in either direction).
+    };
+
+    static SnapAdjustment CalculateSnapDistance(const AZ::Vector3& unsnappedPosition, const AZ::Vector3& axis, const float size)
     {
         // calculate total distance along axis
         const float axisDistance = axis.Dot(unsnappedPosition);
         // round to nearest step size
         const float snappedAxisDistance = floorf((axisDistance / size) + 0.5f) * size;
+
+        return { axisDistance, snappedAxisDistance };
+    }
+
+    AZ::Vector3 CalculateSnappedOffset(const AZ::Vector3& unsnappedPosition, const AZ::Vector3& axis, const float size)
+    {
+        const auto snapAdjustment = CalculateSnapDistance(unsnappedPosition, axis, size);
         // return offset along axis to snap to step size
-        return axis * (snappedAxisDistance - axisDistance);
+        return axis * (snapAdjustment.m_nextSnapDistance - snapAdjustment.m_existingSnapDistance);
+    }
+
+    AZ::Vector3 CalculateSnappedAmount(const AZ::Vector3& unsnappedPosition, const AZ::Vector3& axis, const float size)
+    {
+        const auto snapAdjustment = CalculateSnapDistance(unsnappedPosition, axis, size);
+        // return offset along axis to snap to step size
+        return axis * snapAdjustment.m_nextSnapDistance;
     }
 
     AZ::Vector3 CalculateSnappedTerrainPosition(

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/ManipulatorSnapping.h

@@ -31,24 +31,15 @@ namespace AzToolsFramework
         float m_gridSize;
     };
 
-    /// Structure to encapsulate the current grid snapping state.
-    struct GridSnapAction
-    {
-        GridSnapAction(const GridSnapParameters& gridSnapParameters, bool localSnapping);
-
-        GridSnapParameters m_gridSnapParams;
-        bool m_localSnapping;
-    };
-
     /// Structure to hold transformed incoming viewport interaction from world space to manipulator space.
     struct ManipulatorInteraction
     {
         AZ::Vector3 m_localRayOrigin; ///< The ray origin (start) in the reference from of the manipulator.
         AZ::Vector3 m_localRayDirection; ///< The ray direction in the reference from of the manipulator.
-        float m_scaleReciprocal; ///< The scale reciprocal (1.0 / scale) of the transform used to move the
-                                 ///< ray from world space to local space.
         AZ::Vector3 m_nonUniformScaleReciprocal; ///< Handles inverting any non-uniform scale which was applied
                                                  ///< separately from the transform.
+        float m_scaleReciprocal; ///< The scale reciprocal (1.0 / scale) of the transform used to move the
+                                 ///< ray from world space to local space.
     };
 
     /// Build a ManipulatorInteraction structure from the incoming viewport interaction.
@@ -56,11 +47,16 @@ namespace AzToolsFramework
         const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale,
         const AZ::Vector3& worldRayOrigin, const AZ::Vector3& worldRayDirection);
 
-    /// Calculate the offset along an axis to adjust a position
-    /// to stay snapped to a given grid size.
+    /// Calculate the offset along an axis to adjust a position to stay snapped to a given grid size.
+    /// @note This is snap up or down to the nearest grid segment (e.g. 0.2 snaps to 0.0 -> delta 0.2,
+    /// 0.7 snaps to 1.0 -> delta 0.3).
     AZ::Vector3 CalculateSnappedOffset(
         const AZ::Vector3& unsnappedPosition, const AZ::Vector3& axis, float size);
 
+    /// Return the amount to snap from the starting position given the current grid size.
+    /// @note A movement of more than half size (in either direction) will cause a snap by size.
+    AZ::Vector3 CalculateSnappedAmount(const AZ::Vector3& unsnappedPosition, const AZ::Vector3& axis, float size);
+
     /// For a given point on the terrain, calculate the closest xy position snapped to the grid
     /// (z position is aligned to terrain height, not snapped to z grid)
     AZ::Vector3 CalculateSnappedTerrainPosition(

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/MultiLinearManipulator.cpp

@@ -59,17 +59,16 @@ namespace AzToolsFramework
         const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale, const AZ::Transform& localTransform,
         const ViewportInteraction::MouseInteraction& interaction,
         const AZStd::vector<LinearManipulator::Fixed>& fixedAxes,
-        const AZStd::vector<LinearManipulator::Starter>& starterStates, const GridSnapAction& gridSnapAction)
+        const AZStd::vector<LinearManipulator::Starter>& starterStates, const GridSnapParameters& gridSnapParams)
     {
         MultiLinearManipulator::Action action;
         action.m_viewportId = interaction.m_interactionId.m_viewportId;
         // build up action state for each axis
         for (size_t fixedIndex = 0; fixedIndex < fixedAxes.size(); ++fixedIndex)
         {
-            action.m_actions.push_back(
-                CalculateLinearManipulationDataAction(
-                    fixedAxes[fixedIndex], starterStates[fixedIndex], worldFromLocal, nonUniformScale, localTransform,
-                    gridSnapAction, interaction));
+            action.m_actions.push_back(CalculateLinearManipulationDataAction(
+                fixedAxes[fixedIndex], starterStates[fixedIndex], worldFromLocal, nonUniformScale, localTransform, gridSnapParams,
+                interaction));
         }
 
         return action;
@@ -79,8 +78,6 @@ namespace AzToolsFramework
         const ViewportInteraction::MouseInteraction& interaction, const float rayIntersectionDistance)
     {
         const AZ::Transform worldFromLocalUniformScale = TransformUniformScale(GetSpace());
-
-        const GridSnapParameters gridSnapParams = GridSnapSettings(interaction.m_interactionId.m_viewportId);
         const AzFramework::CameraState cameraState = GetCameraState(interaction.m_interactionId.m_viewportId);
 
         // build up initial start state for each axis
@@ -88,20 +85,19 @@ namespace AzToolsFramework
         {
             // note: m_localTransform must not be made uniform as it may contain a local scale we want to snap
             const auto linearStart = CalculateLinearManipulationDataStart(
-                fixed, worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(),
-                GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()), interaction,
-                rayIntersectionDistance, cameraState);
+                fixed, worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(), interaction, rayIntersectionDistance,
+                cameraState);
 
             m_starters.push_back(linearStart);
         }
 
         if (m_onLeftMouseDownCallback)
         {
-            const GridSnapAction gridSnapAction = GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt());
+            const GridSnapParameters gridSnapParams = GridSnapSettings(interaction.m_interactionId.m_viewportId);
             // pass action containing all linear actions for each axis to handler
             m_onLeftMouseDownCallback(BuildMultiLinearManipulatorAction(
                 worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(),
-                interaction, m_fixedAxes, m_starters, gridSnapAction));
+                interaction, m_fixedAxes, m_starters, gridSnapParams));
         }
     }
 
@@ -111,11 +107,9 @@ namespace AzToolsFramework
         {
             const AZ::Transform worldFromLocalUniformScale = TransformUniformScale(GetSpace());
             const GridSnapParameters gridSnapParams = GridSnapSettings(interaction.m_interactionId.m_viewportId);
-            const GridSnapAction gridSnapAction = GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt());
-
             m_onMouseMoveCallback(BuildMultiLinearManipulatorAction(
                 worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(),
-                interaction, m_fixedAxes, m_starters, gridSnapAction));
+                interaction, m_fixedAxes, m_starters, gridSnapParams));
         }
     }
 
@@ -125,11 +119,9 @@ namespace AzToolsFramework
         {
             const AZ::Transform worldFromLocalUniformScale = TransformUniformScale(GetSpace());
             const GridSnapParameters gridSnapParams = GridSnapSettings(interaction.m_interactionId.m_viewportId);
-            const GridSnapAction gridSnapAction = GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt());
-
             m_onLeftMouseUpCallback(BuildMultiLinearManipulatorAction(
                 worldFromLocalUniformScale, GetNonUniformScale(), GetLocalTransform(),
-                interaction, m_fixedAxes, m_starters, gridSnapAction));
+                interaction, m_fixedAxes, m_starters, gridSnapParams));
 
             m_starters.clear();
         }

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/MultiLinearManipulator.h

@@ -20,8 +20,6 @@
 
 namespace AzToolsFramework
 {
-    struct GridSnapAction;
-
     //! MultiLinearManipulator serves as a visual tool for users to modify values
     //! in one or more dimensions on axes defined in 3D space.
     class MultiLinearManipulator

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/PlanarManipulator.cpp

@@ -22,8 +22,7 @@
 namespace AzToolsFramework
 {
     PlanarManipulator::StartInternal PlanarManipulator::CalculateManipulationDataStart(
-        const Fixed& fixed, const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale,
-        const AZ::Transform& localTransform, const GridSnapAction& gridSnapAction,
+        const Fixed& fixed, const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale, const AZ::Transform& localTransform,
         const ViewportInteraction::MouseInteraction& interaction, const float intersectionDistance)
     {
         const ManipulatorInteraction manipulatorInteraction =
@@ -31,8 +30,6 @@ namespace AzToolsFramework
                 worldFromLocal, nonUniformScale, interaction.m_mousePick.m_rayOrigin, interaction.m_mousePick.m_rayDirection);
 
         const AZ::Vector3 normal = TransformDirectionNoScaling(localTransform, fixed.m_normal);
-        const AZ::Vector3 axis1 = TransformDirectionNoScaling(localTransform, fixed.m_axis1);
-        const AZ::Vector3 axis2 = TransformDirectionNoScaling(localTransform, fixed.m_axis2);
 
         // initial intersect point
         const AZ::Vector3 localIntersectionPoint =
@@ -43,25 +40,14 @@ namespace AzToolsFramework
             manipulatorInteraction.m_localRayOrigin, manipulatorInteraction.m_localRayDirection,
             localIntersectionPoint, normal, startInternal.m_localHitPosition);
 
-        const float scaleRecip = manipulatorInteraction.m_scaleReciprocal;
-        const float gridSize = gridSnapAction.m_gridSnapParams.m_gridSize;
-        const bool snapping = gridSnapAction.m_gridSnapParams.m_gridSnap;
-
-        // calculate amount to snap to align with grid
-        const AZ::Vector3 snapOffset = snapping && !gridSnapAction.m_localSnapping
-            ? CalculateSnappedOffset(localTransform.GetTranslation(), axis1, gridSize * scaleRecip) +
-              CalculateSnappedOffset(localTransform.GetTranslation(), axis2, gridSize * scaleRecip)
-            : AZ::Vector3::CreateZero();
-
-        startInternal.m_snapOffset = snapOffset;
-        startInternal.m_localPosition = localTransform.GetTranslation() + snapOffset;
+        startInternal.m_localPosition = localTransform.GetTranslation();
 
         return startInternal;
     }
 
     PlanarManipulator::Action PlanarManipulator::CalculateManipulationDataAction(
-        const Fixed& fixed, const StartInternal& startInternal, const AZ::Transform& worldFromLocal,
-        const AZ::Vector3& nonUniformScale, const AZ::Transform& localTransform, const GridSnapAction& gridSnapAction,
+        const Fixed& fixed, const StartInternal& startInternal, const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale,
+        const AZ::Transform& localTransform, const GridSnapParameters& gridSnapParams,
         const ViewportInteraction::MouseInteraction& interaction)
     {
         const ManipulatorInteraction manipulatorInteraction =
@@ -88,20 +74,18 @@ namespace AzToolsFramework
         const AZ::Vector3 hitDelta = (localHitPosition - startInternal.m_localHitPosition) / nonUniformScale;
         const AZ::Vector3 unsnappedOffset = axis1.Dot(hitDelta) * axis1 + axis2.Dot(hitDelta) * axis2;
 
-        const float scaleRecip = manipulatorInteraction.m_scaleReciprocal;
         const AZ::Vector3 nonUniformScaleRecip = manipulatorInteraction.m_nonUniformScaleReciprocal;
-        const float gridSize = gridSnapAction.m_gridSnapParams.m_gridSize;
-        const bool snapping = gridSnapAction.m_gridSnapParams.m_gridSnap;
+        const float scaleRecip = manipulatorInteraction.m_scaleReciprocal;
+        const float gridSize = gridSnapParams.m_gridSize;
+        const bool snapping = gridSnapParams.m_gridSnap;
 
         Action action;
         action.m_fixed = fixed;
         action.m_start.m_localPosition = startInternal.m_localPosition;
-        action.m_start.m_snapOffset = startInternal.m_snapOffset;
         action.m_start.m_localHitPosition = startInternal.m_localHitPosition;
         action.m_current.m_localOffset = snapping
-            ? unsnappedOffset +
-                CalculateSnappedOffset(unsnappedOffset, axis1, gridSize * scaleRecip * nonUniformScaleRecip.Dot(axis1)) +
-                CalculateSnappedOffset(unsnappedOffset, axis2, gridSize * scaleRecip * nonUniformScaleRecip.Dot(axis2))
+            ? CalculateSnappedAmount(unsnappedOffset, axis1, gridSize * scaleRecip * nonUniformScaleRecip.Dot(fixed.m_axis1)) +
+                CalculateSnappedAmount(unsnappedOffset, axis2, gridSize * scaleRecip * nonUniformScaleRecip.Dot(fixed.m_axis2))
             : unsnappedOffset;
 
         // record what modifier keys are held during this action
@@ -141,18 +125,17 @@ namespace AzToolsFramework
     {
         const AZ::Transform worldFromLocalUniformScale = TransformUniformScale(GetSpace());
 
-        const GridSnapParameters gridSnapParams = GridSnapSettings(interaction.m_interactionId.m_viewportId);
-
         m_startInternal = CalculateManipulationDataStart(
             m_fixed, worldFromLocalUniformScale, GetNonUniformScale(), TransformNormalizedScale(GetLocalTransform()),
-            GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()),
             interaction, rayIntersectionDistance);
 
         if (m_onLeftMouseDownCallback)
         {
+            const GridSnapParameters gridSnapParams = GridSnapSettings(interaction.m_interactionId.m_viewportId);
+
             m_onLeftMouseDownCallback(CalculateManipulationDataAction(
                 m_fixed, m_startInternal, worldFromLocalUniformScale, GetNonUniformScale(), TransformNormalizedScale(GetLocalTransform()),
-                GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()), interaction));
+                gridSnapParams, interaction));
         }
     }
 
@@ -164,8 +147,7 @@ namespace AzToolsFramework
 
             m_onMouseMoveCallback(CalculateManipulationDataAction(
                 m_fixed, m_startInternal, TransformUniformScale(GetSpace()), GetNonUniformScale(),
-                TransformNormalizedScale(GetLocalTransform()),
-                GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()), interaction));
+                TransformNormalizedScale(GetLocalTransform()), gridSnapParams, interaction));
         }
     }
 
@@ -177,8 +159,7 @@ namespace AzToolsFramework
 
             m_onLeftMouseUpCallback(CalculateManipulationDataAction(
                 m_fixed, m_startInternal, TransformUniformScale(GetSpace()), GetNonUniformScale(),
-                TransformNormalizedScale(GetLocalTransform()),
-                GridSnapAction(gridSnapParams, interaction.m_keyboardModifiers.Alt()), interaction));
+                TransformNormalizedScale(GetLocalTransform()), gridSnapParams, interaction));
         }
     }
 
@@ -195,8 +176,7 @@ namespace AzToolsFramework
                 const GridSnapParameters gridSnapParams = GridSnapSettings(mouseInteraction.m_interactionId.m_viewportId);
                 const auto action = CalculateManipulationDataAction(
                     m_fixed, m_startInternal, TransformUniformScale(GetSpace()), GetNonUniformScale(),
-                    TransformNormalizedScale(GetLocalTransform()),
-                    GridSnapAction(gridSnapParams, mouseInteraction.m_keyboardModifiers.Alt()), mouseInteraction);
+                    TransformNormalizedScale(GetLocalTransform()), gridSnapParams, mouseInteraction);
 
                 // display the exact hit (ray intersection) of the mouse pick on the manipulator
                 DrawTransformAxes(

Code/Framework/AzToolsFramework/AzToolsFramework/Manipulators/PlanarManipulator.h

@@ -21,7 +21,7 @@
 namespace AzToolsFramework
 {
     class ManipulatorView;
-    struct GridSnapAction;
+    struct GridSnapParameters;
 
     /// PlanarManipulator serves as a visual tool for users to modify values
     /// in two dimension in a plane defined two non-collinear axes in 3D space.
@@ -58,7 +58,6 @@ namespace AzToolsFramework
         {
             AZ::Vector3 m_localPosition; ///< The current position of the manipulator in local space.
             AZ::Vector3 m_localHitPosition; ///< The intersection point in local space between the ray and the manipulator when the mouse down event happens.
-            AZ::Vector3 m_snapOffset; ///< The snap offset amount to ensure manipulator is aligned to the grid.
         };
 
         /// The state of the manipulator during an interaction.
@@ -120,7 +119,6 @@ namespace AzToolsFramework
         {
             AZ::Vector3 m_localPosition; ///< The starting position of the manipulator in local space.
             AZ::Vector3 m_localHitPosition; ///< The intersection point in world space between the ray and the manipulator when the mouse down event happens.
-            AZ::Vector3 m_snapOffset; ///< The snap offset amount to ensure manipulator is aligned to the grid.
         };
 
         Fixed m_fixed;
@@ -134,12 +132,11 @@ namespace AzToolsFramework
 
         static StartInternal CalculateManipulationDataStart(
             const Fixed& fixed, const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale,
-            const AZ::Transform& localTransform, const GridSnapAction& gridSnapAction,
-            const ViewportInteraction::MouseInteraction& interaction, float intersectionDistance);
+            const AZ::Transform& localTransform, const ViewportInteraction::MouseInteraction& interaction, float intersectionDistance);
 
         static Action CalculateManipulationDataAction(
-            const Fixed& fixed, const StartInternal& startInternal, const AZ::Transform& worldFromLocal,
-            const AZ::Vector3& nonUniformScale, const AZ::Transform& localTransform,
-            const GridSnapAction& gridSnapAction, const ViewportInteraction::MouseInteraction& interaction);
+            const Fixed& fixed, const StartInternal& startInternal, const AZ::Transform& worldFromLocal, const AZ::Vector3& nonUniformScale,
+            const AZ::Transform& localTransform, const GridSnapParameters& gridSnapParams,
+            const ViewportInteraction::MouseInteraction& interaction);
     };
 } // namespace AzToolsFramework

Code/Framework/AzToolsFramework/AzToolsFramework/ToolsComponents/EditorNonUniformScaleComponentMode.cpp

@@ -37,13 +37,13 @@ namespace AzToolsFramework
                 axisLength, AzFramework::ViewportColors::XAxisColor, AzFramework::ViewportColors::YAxisColor,
                 AzFramework::ViewportColors::ZAxisColor);
 
-            auto mouseDownCallback = [this](const LinearManipulator::Action& action) {
+            auto mouseDownCallback = [this]([[maybe_unused]] const LinearManipulator::Action& action)
+            {
                 AZ::Vector3 nonUniformScale = AZ::Vector3::CreateOne();
-
                 AZ::NonUniformScaleRequestBus::EventResult(
                     nonUniformScale, m_entityComponentIdPair.GetEntityId(), &AZ::NonUniformScaleRequests::GetScale);
 
-                m_initialScale = nonUniformScale + action.m_start.m_scaleSnapOffset;
+                m_initialScale = nonUniformScale;
 
                 AZ::NonUniformScaleRequestBus::Event(
                     m_entityComponentIdPair.GetEntityId(), &AZ::NonUniformScaleRequests::SetScale, m_initialScale);
@@ -51,29 +51,37 @@ namespace AzToolsFramework
 
             m_manipulators->InstallAxisLeftMouseDownCallback(mouseDownCallback);
 
-            m_manipulators->InstallAxisMouseMoveCallback([this](const LinearManipulator::Action& action) {
-                const AZ::Vector3 scaleMultiplier =
-                    (AZ::Vector3::CreateOne() + ((action.LocalScaleOffset() * action.m_start.m_sign) / m_initialScale));
+            m_manipulators->InstallAxisMouseMoveCallback(
+                [this](const LinearManipulator::Action& action)
+                {
+                    const AZ::Vector3 scaleMultiplier =
+                        (AZ::Vector3::CreateOne() + ((action.LocalScaleOffset() * action.m_start.m_sign) / m_initialScale));
 
-                AZ::NonUniformScaleRequestBus::Event(
-                    m_entityComponentIdPair.GetEntityId(), &AZ::NonUniformScaleRequests::SetScale,
-                    (scaleMultiplier * m_initialScale).GetClamp(AZ::Vector3(AZ::MinTransformScale), AZ::Vector3(AZ::MaxTransformScale)));
-            });
+                    AZ::NonUniformScaleRequestBus::Event(
+                        m_entityComponentIdPair.GetEntityId(), &AZ::NonUniformScaleRequests::SetScale,
+                        (scaleMultiplier * m_initialScale)
+                            .GetClamp(AZ::Vector3(AZ::MinTransformScale), AZ::Vector3(AZ::MaxTransformScale)));
+                });
 
             m_manipulators->InstallUniformLeftMouseDownCallback(mouseDownCallback);
 
-            m_manipulators->InstallUniformMouseMoveCallback([this](const LinearManipulator::Action& action) {
-                const auto sumVectorElements = [](const AZ::Vector3& vec) { return vec.GetX() + vec.GetY() + vec.GetZ(); };
+            m_manipulators->InstallUniformMouseMoveCallback(
+                [this](const LinearManipulator::Action& action)
+                {
+                    const auto sumVectorElements = [](const AZ::Vector3& vec)
+                    {
+                        return vec.GetX() + vec.GetY() + vec.GetZ();
+                    };
 
-                const float minScaleMultiplier = AZ::MinTransformScale / m_initialScale.GetMinElement();
-                const float maxScaleMultiplier = AZ::MaxTransformScale / m_initialScale.GetMaxElement();
-                const float scaleMultiplier = AZ::GetClamp(
-                    1.0f + sumVectorElements(action.m_start.m_sign * action.LocalScaleOffset() / m_initialScale), minScaleMultiplier,
-                    maxScaleMultiplier);
+                    const float minScaleMultiplier = AZ::MinTransformScale / m_initialScale.GetMinElement();
+                    const float maxScaleMultiplier = AZ::MaxTransformScale / m_initialScale.GetMaxElement();
+                    const float scaleMultiplier = AZ::GetClamp(
+                        1.0f + sumVectorElements(action.m_start.m_sign * action.LocalScaleOffset() / m_initialScale), minScaleMultiplier,
+                        maxScaleMultiplier);
 
-                AZ::NonUniformScaleRequestBus::Event(
-                    m_entityComponentIdPair.GetEntityId(), &AZ::NonUniformScaleRequests::SetScale, scaleMultiplier * m_initialScale);
-            });
+                    AZ::NonUniformScaleRequestBus::Event(
+                        m_entityComponentIdPair.GetEntityId(), &AZ::NonUniformScaleRequests::SetScale, scaleMultiplier * m_initialScale);
+                });
         }
 
         NonUniformScaleComponentMode::~NonUniformScaleComponentMode()

Code/Framework/AzToolsFramework/AzToolsFramework/ViewportSelection/EditorTransformComponentSelection.cpp

@@ -423,15 +423,14 @@ namespace AzToolsFramework
         }
     }
 
-    static void InitializeTranslationLookup(
-        EntityIdManipulators& entityIdManipulators, const AZ::Vector3& snapOffset)
+    static void InitializeTranslationLookup(EntityIdManipulators& entityIdManipulators)
     {
         AZ_PROFILE_FUNCTION(AZ::Debug::ProfileCategory::AzToolsFramework);
 
         for (auto& entityIdLookup : entityIdManipulators.m_lookups)
         {
             entityIdLookup.second.m_initial =
-                AZ::Transform::CreateTranslation(GetWorldTranslation(entityIdLookup.first) + snapOffset);
+                AZ::Transform::CreateTranslation(GetWorldTranslation(entityIdLookup.first));
         }
     }
 
@@ -820,7 +819,7 @@ namespace AzToolsFramework
             // moving with ctrl - setting override
             pivotOverrideFrame.m_translationOverride =
                 entityIdManipulators.m_manipulators->GetLocalTransform().GetTranslation();
-            InitializeTranslationLookup(entityIdManipulators, -action.LocalPositionOffset());
+            InitializeTranslationLookup(entityIdManipulators);
         }
         else
         {
@@ -1277,12 +1276,12 @@ namespace AzToolsFramework
 
         // linear
         translationManipulators->InstallLinearManipulatorMouseDownCallback(
-            [this, manipulatorEntityIds](const LinearManipulator::Action& action) mutable
+            [this, manipulatorEntityIds]([[maybe_unused]] const LinearManipulator::Action& action) mutable
         {
             // important to sort entityIds based on hierarchy order when updating transforms
             BuildSortedEntityIdVectorFromEntityIdMap(m_entityIdManipulators.m_lookups, manipulatorEntityIds->m_entityIds);
 
-            InitializeTranslationLookup(m_entityIdManipulators, action.m_start.m_positionSnapOffset);
+            InitializeTranslationLookup(m_entityIdManipulators);
 
             m_axisPreview.m_translation = m_entityIdManipulators.m_manipulators->GetLocalTransform().GetTranslation();
             m_axisPreview.m_orientation = QuaternionFromTransformNoScaling(
@@ -1302,19 +1301,19 @@ namespace AzToolsFramework
         });
 
         translationManipulators->InstallLinearManipulatorMouseUpCallback(
-            [this](const LinearManipulator::Action& /*action*/) mutable
+            [this]([[maybe_unused]] const LinearManipulator::Action& action) mutable
         {
             EndRecordManipulatorCommand();
         });
 
         // planar
         translationManipulators->InstallPlanarManipulatorMouseDownCallback(
-            [this, manipulatorEntityIds](const PlanarManipulator::Action& action)
+            [this, manipulatorEntityIds]([[maybe_unused]] const PlanarManipulator::Action& action)
         {
             // important to sort entityIds based on hierarchy order when updating transforms
             BuildSortedEntityIdVectorFromEntityIdMap(m_entityIdManipulators.m_lookups, manipulatorEntityIds->m_entityIds);
 
-            InitializeTranslationLookup(m_entityIdManipulators, action.m_start.m_snapOffset);
+            InitializeTranslationLookup(m_entityIdManipulators);
 
             m_axisPreview.m_translation = m_entityIdManipulators.m_manipulators->GetLocalTransform().GetTranslation();
             m_axisPreview.m_orientation = QuaternionFromTransformNoScaling(
@@ -1340,11 +1339,11 @@ namespace AzToolsFramework
 
         // surface
         translationManipulators->InstallSurfaceManipulatorMouseDownCallback(
-            [this, manipulatorEntityIds](const SurfaceManipulator::Action& action)
+            [this, manipulatorEntityIds]([[maybe_unused]] const SurfaceManipulator::Action& action)
         {
             BuildSortedEntityIdVectorFromEntityIdMap(m_entityIdManipulators.m_lookups, manipulatorEntityIds->m_entityIds);
 
-            InitializeTranslationLookup(m_entityIdManipulators, action.m_start.m_snapOffset);
+            InitializeTranslationLookup(m_entityIdManipulators);
 
             m_axisPreview.m_translation = m_entityIdManipulators.m_manipulators->GetLocalTransform().GetTranslation();
             m_axisPreview.m_orientation = QuaternionFromTransformNoScaling(
@@ -3326,26 +3325,16 @@ namespace AzToolsFramework
     }
 
     static void DrawManipulatorGrid(
-        AzFramework::DebugDisplayRequests& debugDisplay, const EntityIdManipulators& entityIdManipulators,
-        const float gridSize, const float localSnapping)
+        AzFramework::DebugDisplayRequests& debugDisplay, const EntityIdManipulators& entityIdManipulators, const float gridSize)
     {
         const AZ::Matrix3x3 orientation =
             AZ::Matrix3x3::CreateFromTransform(entityIdManipulators.m_manipulators->GetLocalTransform());
 
-        const AZ::Vector3 unsnappedTranslation =
+        const AZ::Vector3 translation =
             entityIdManipulators.m_manipulators->GetLocalTransform().GetTranslation();
 
-        // calculate the offset to snap by to align the manipulator to the grid
-        // note: only perform this if we are not snapping in local space
-        const AZ::Vector3 snappedOffset = !localSnapping
-            ? CalculateSnappedOffset(unsnappedTranslation, orientation.GetBasisX(), gridSize) +
-              CalculateSnappedOffset(unsnappedTranslation, orientation.GetBasisY(), gridSize)
-            : AZ::Vector3::CreateZero();
-
-        const AZ::Vector3 snappedTranslation = unsnappedTranslation + snappedOffset;
-
         DrawSnappingGrid(
-            debugDisplay, AZ::Transform::CreateFromMatrix3x3AndTranslation(orientation, snappedTranslation),
+            debugDisplay, AZ::Transform::CreateFromMatrix3x3AndTranslation(orientation, translation),
             gridSize);
     }
 
@@ -3484,7 +3473,7 @@ namespace AzToolsFramework
                 const GridSnapParameters gridSnapParams = GridSnapSettings(viewportInfo.m_viewportId);
                 if (gridSnapParams.m_gridSnap && m_entityIdManipulators.m_manipulators)
                 {
-                    DrawManipulatorGrid(debugDisplay, m_entityIdManipulators, gridSnapParams.m_gridSize, modifiers.Alt());
+                    DrawManipulatorGrid(debugDisplay, m_entityIdManipulators, gridSnapParams.m_gridSize);
                 }
             }
         }