Prevent the camera from easily being set to an invalid orientation (#6203)

* add temporary debug logging

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

* improvement for box select sometimes getting stuck on

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

* add temporary debug logging

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

* improvement for box select sometimes getting stuck on

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

* remove temporary logging

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

* fixes for camera pitch issues

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

* missed file with camera pitch fixes

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

* remove debug logs

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

* add some tests for new pitch constraint updates

Signed-off-by: Tom Hulton-Harrop <82228511+hultonha@users.noreply.github.com>

Code/Framework/AzFramework/AzFramework/Viewport/CameraInput.cpp

@@ -335,10 +335,13 @@ namespace AzFramework
         Camera nextCamera = targetCamera;
 
         const float rotateSpeed = m_rotateSpeedFn();
-        nextCamera.m_pitch -= float(cursorDelta.m_y) * rotateSpeed * Invert(m_invertPitchFn());
-        nextCamera.m_yaw -= float(cursorDelta.m_x) * rotateSpeed * Invert(m_invertYawFn());
+        const float deltaPitch = aznumeric_cast<float>(cursorDelta.m_y) * rotateSpeed * Invert(m_invertPitchFn());
+        const float deltaYaw = aznumeric_cast<float>(cursorDelta.m_x) * rotateSpeed * Invert(m_invertYawFn());
 
+        nextCamera.m_pitch -= deltaPitch;
+        nextCamera.m_yaw -= deltaYaw;
         nextCamera.m_yaw = WrapYawRotation(nextCamera.m_yaw);
+
         if (m_constrainPitch())
         {
             nextCamera.m_pitch = ClampPitchRotation(nextCamera.m_pitch);

Code/Framework/AzFramework/AzFramework/Viewport/CameraInput.h

@@ -25,6 +25,9 @@ namespace AzFramework
 
     struct WindowSize;
 
+    //! Tolerance to use when limiting pitch to avoid reaching +/-Pi/2 exactly.
+    constexpr float CameraPitchTolerance = 1.0e-4f;
+
     //! Returns Euler angles (pitch, roll, yaw) for the incoming orientation.
     //! @note Order of rotation is Z, Y, X.
     AZ::Vector3 EulerAngles(const AZ::Matrix3x3& orientation);
@@ -318,11 +321,26 @@ namespace AzFramework
         return m_handlingEvents;
     }
 
-    //! Clamps pitch to be +/-90 degrees (-Pi/2, Pi/2).
+    //! Returns min/max values for camera pitch (in radians).
+    inline AZStd::tuple<float, float> CameraPitchMinMaxRadians()
+    {
+        return { -AZ::Constants::HalfPi, AZ::Constants::HalfPi };
+    }
+
+    //! Returns min/max values for camera pitch (in radians) including a small tolerance at each
+    //! extreme (looking directly up or down) to avoid floating point accuracy issues.
+    inline AZStd::tuple<float, float> CameraPitchMinMaxRadiansWithTolerance()
+    {
+        const auto [pitchMinRadians, pitchMaxRadians] = CameraPitchMinMaxRadians();
+        return { pitchMinRadians + CameraPitchTolerance, pitchMaxRadians - CameraPitchTolerance };
+    }
+
+    //! Clamps pitch to be +/-90 degrees (-Pi/2, Pi/2) with a minor tolerance at each extreme.
     //! @param pitch Pitch angle in radians.
     inline float ClampPitchRotation(const float pitch)
     {
-        return AZ::GetClamp(pitch, -AZ::Constants::HalfPi, AZ::Constants::HalfPi);
+        const auto [pitchMin, pitchMax] = CameraPitchMinMaxRadiansWithTolerance();
+        return AZ::GetClamp(pitch, pitchMin, pitchMax);
     }
 
     //! Ensures yaw wraps between 0 and 360 degrees (0, 2Pi).

Code/Framework/AzFramework/Tests/CameraInputTests.cpp

@@ -322,6 +322,17 @@ namespace UnitTest
         EXPECT_THAT(m_camera.m_offset, IsClose(AZ::Vector3::CreateZero()));
     }
 
+    TEST(CameraInput, CameraPitchIsClampedWithExpectedTolerance)
+    {
+        const auto [expectedMinPitch, expectedMaxPitch] = AzFramework::CameraPitchMinMaxRadiansWithTolerance();
+        const float minPitch = AzFramework::ClampPitchRotation(-AZ::Constants::HalfPi);
+        const float maxPitch = AzFramework::ClampPitchRotation(AZ::Constants::HalfPi);
+
+        using ::testing::FloatNear;
+        EXPECT_THAT(minPitch, FloatNear(expectedMinPitch, AzFramework::CameraPitchTolerance));
+        EXPECT_THAT(maxPitch, FloatNear(expectedMaxPitch, AzFramework::CameraPitchTolerance));
+    }
+
     TEST_F(CameraInputFixture, OrbitRotateCameraInputRotatesPitchOffsetByNinetyDegreesWithRequiredPixelDelta)
     {
         const auto cameraStartingPosition = AZ::Vector3::CreateAxisY(-20.0f);

Code/Framework/AzToolsFramework/AzToolsFramework/ViewportSelection/EditorBoxSelect.cpp

@@ -64,7 +64,8 @@ namespace AzToolsFramework
                 }
             }
 
-            if (clickOutcome == AzFramework::ClickDetector::ClickOutcome::Release)
+            if (clickOutcome == AzFramework::ClickDetector::ClickOutcome::Release ||
+                clickOutcome == AzFramework::ClickDetector::ClickOutcome::Click)
             {
                 if (m_leftMouseUp)
                 {