Add placeholder steering wheel option for VR driving

runtime/include/runtime_config.h

@@ -76,6 +76,7 @@ struct RuntimeUserConfig {
     std::optional<float> vrCockpitUnitsPerMeter;
     std::optional<bool> vrSteeringWheel;
     std::optional<bool> vrNativeSteeringWheel;
+    std::optional<bool> vrPlaceholderSteeringWheel;
     std::optional<bool> vrObjectCulling;
     std::optional<bool> vrHandSteering;
     std::optional<std::string> vrCockpitItemHand;
@@ -231,13 +232,17 @@ inline constexpr float kVrCockpitUnitsPerMeterDefault = 100.0f;
 inline constexpr float kVrCockpitUnitsPerMeterMin = 20.0f;
 inline constexpr float kVrCockpitUnitsPerMeterMax = 400.0f;
 // The vehicle's steering wheel or handlebar turns with the steering; the
-// vehicle's own model is animated unless native_steering_wheel is off, which
-// draws a separate VR wheel instead. Hand steering (grabbing that wheel with
-// the tracked controllers, by heurazy) comes with it: the stick still steers
-// until a grip actually takes hold of the wheel. Both launchers register
-// hand_steering with this same default.
+// vehicle's own model is animated unless native_steering_wheel is off.
+// placeholder_steering_wheel draws a separate VR wheel or handlebar whenever
+// the vehicle's own is not the one turning (native_steering_wheel off, or a
+// draw that does not take the animated copy); off, the vehicle's own is all
+// there is. Hand steering (grabbing that wheel with the tracked controllers,
+// by heurazy) comes with it: the stick still steers until a grip actually
+// takes hold of the wheel. Both launchers register hand_steering with this
+// same default.
 inline constexpr bool kVrSteeringWheelDefault = true;
 inline constexpr bool kVrNativeSteeringWheelDefault = true;
+inline constexpr bool kVrPlaceholderSteeringWheelDefault = false;
 inline constexpr bool kVrHandSteeringDefault = true;
 inline constexpr const char* kVrCockpitItemHandDefault = "left";
 // A quick swing of the item hand forward or back throws the item that way.
@@ -594,9 +599,11 @@ inline void EnsureConfigFile() {
               "first_person_rotation = \"yaw_pitch\"\n"
               "# In the cockpit the vehicle's steering wheel or handlebar turns\n"
               "# with the steering. native_steering_wheel animates the vehicle's\n"
-              "# own model; false draws a separate VR wheel instead.\n"
+              "# own model. placeholder_steering_wheel draws a separate VR wheel\n"
+              "# or handlebar whenever the vehicle's own is not the one turning.\n"
               "steering_wheel = true\n"
               "native_steering_wheel = true\n"
+              "placeholder_steering_wheel = false\n"
               "# The game hides karts and objects its own camera cannot see.\n"
               "# object_culling = false draws them anyway, so a head turn or a\n"
               "# look over the shoulder shows them; it costs GPU time.\n"
@@ -887,6 +894,7 @@ inline RuntimeUserConfig ParseConfigDocument(const toml::value& document) {
         readRangedFloat("cockpit_units_per_meter", kVrCockpitUnitsPerMeterMin, kVrCockpitUnitsPerMeterMax);
     config.vrSteeringWheel = FindConfigValue<bool>(document, "vr", "steering_wheel");
     config.vrNativeSteeringWheel = FindConfigValue<bool>(document, "vr", "native_steering_wheel");
+    config.vrPlaceholderSteeringWheel = FindConfigValue<bool>(document, "vr", "placeholder_steering_wheel");
     config.vrObjectCulling = FindConfigValue<bool>(document, "vr", "object_culling");
     config.vrHandSteering = FindConfigValue<bool>(document, "vr", "hand_steering");
     config.vrCockpitItemHand = FindConfigValue<std::string>(document, "vr", "cockpit_item_hand");
@@ -1283,6 +1291,11 @@ inline bool SetVrNativeSteeringWheel(bool value) {
     return WriteSetting("vr", "native_steering_wheel", value ? "true" : "false");
 }
 
+inline bool SetVrPlaceholderSteeringWheel(bool value) {
+    Mutable().vrPlaceholderSteeringWheel = value;
+    return WriteSetting("vr", "placeholder_steering_wheel", value ? "true" : "false");
+}
+
 inline bool SetVrObjectCulling(bool value) {
     Mutable().vrObjectCulling = value;
     return WriteSetting("vr", "object_culling", value ? "true" : "false");
@@ -1787,6 +1800,10 @@ inline bool VrNativeSteeringWheel(bool fallback = kVrNativeSteeringWheelDefault)
     return Get().vrNativeSteeringWheel.value_or(fallback);
 }
 
+inline bool VrPlaceholderSteeringWheel(bool fallback = kVrPlaceholderSteeringWheelDefault) {
+    return Get().vrPlaceholderSteeringWheel.value_or(fallback);
+}
+
 inline bool VrObjectCulling(bool fallback = kVrObjectCullingDefault) {
     return Get().vrObjectCulling.value_or(fallback);
 }

runtime/include/vr/openxr_driving.h

@@ -91,6 +91,15 @@ inline float MaxWheelAngle(bool bike, const WheelTuning& tuning) noexcept {
     return clamped * 0.01745329252f;
 }
 
+// Whether the overlay draws a separate VR wheel or handlebar: only when
+// placeholder_steering_wheel asks for one and the vehicle's own is not the one
+// turning. Without it the hands reach for the vehicle's own wherever its
+// geometry is known, turning or not.
+inline bool DrawsPlaceholderControl(bool steering_wheel, bool native_steering_wheel, bool native_mesh_prepared,
+                                    bool placeholder) noexcept {
+    return placeholder && steering_wheel && !(native_steering_wheel && native_mesh_prepared);
+}
+
 // Grips only grab. As a Wii Remote they press nothing at all (C, the game's
 // look-behind, is right B); as a gamepad they are the shoulders, so a holding
 // hand's squeeze is released for the game. The wheel replaces the left stick's

runtime/src/settings_overlay.cpp

@@ -168,6 +168,7 @@ int g_vrFirstPersonSeat = RuntimeConfigFile::VrFirstPersonSeat() == "custom" ? 1
 float g_vrCockpitUnitsPerMeter = RuntimeConfigFile::VrCockpitUnitsPerMeter();
 bool g_vrSteeringWheel = RuntimeConfigFile::VrSteeringWheel();
 bool g_vrNativeSteeringWheel = RuntimeConfigFile::VrNativeSteeringWheel();
+bool g_vrPlaceholderSteeringWheel = RuntimeConfigFile::VrPlaceholderSteeringWheel();
 bool g_vrObjectCulling = RuntimeConfigFile::VrObjectCulling();
 bool g_vrHandSteering = RuntimeConfigFile::VrHandSteering();
 constexpr std::array<const char*, 3> kVrCockpitItemHands{"Left", "Right", "Off"};
@@ -1214,9 +1215,15 @@ void DrawVrSteeringWheelSettings() {
         mkw::vr::MkwVRFirstPersonApplyConfiguredSettings();
     }
     if (ImGui::IsItemHovered()) {
-        ImGui::SetTooltip("Turns the wheel or handlebar of the vehicle's own model. Off draws a "
-                          "separate VR wheel instead, which is also what appears when a vehicle's "
-                          "own wheel cannot be animated.");
+        ImGui::SetTooltip("Turns the wheel or handlebar of the vehicle's own model.");
+    }
+    if (ImGui::Checkbox("Placeholder wheel or handlebar", &g_vrPlaceholderSteeringWheel)) {
+        RuntimeConfigFile::SetVrPlaceholderSteeringWheel(g_vrPlaceholderSteeringWheel);
+    }
+    if (ImGui::IsItemHovered()) {
+        ImGui::SetTooltip("Draws a separate VR wheel (karts) or handlebar (bikes) whenever the "
+                          "vehicle's own is not the one turning: with the option above off, or while "
+                          "the game's draws do not take its animation, as in the race's opening pan.");
     }
     ImGui::EndDisabled();
     if (ImGui::Checkbox("Hand steering (by heurazy)", &g_vrHandSteering)) {
@@ -1317,7 +1324,8 @@ void DrawVrSteeringWheelSettings() {
                             anchor.bike ? "handlebar" : "wheel",
                             !anchor.native_wheel.valid ? "grips not found"
                             : anchor.native_mesh_prepared ? "vehicle's own"
-                                                          : "VR wheel",
+                            : g_vrSteeringWheel && g_vrPlaceholderSteeringWheel ? "placeholder"
+                                                                                : "vehicle's own, not animated",
                             anchor.units_per_meter, GxNativeWheel::LastDrawCount());
     }
 }
@@ -1769,6 +1777,7 @@ void DrawVrCameraSettings() {
         g_vrCockpitUnitsPerMeter = RuntimeConfigFile::kVrCockpitUnitsPerMeterDefault;
         g_vrSteeringWheel = RuntimeConfigFile::kVrSteeringWheelDefault;
         g_vrNativeSteeringWheel = RuntimeConfigFile::kVrNativeSteeringWheelDefault;
+        g_vrPlaceholderSteeringWheel = RuntimeConfigFile::kVrPlaceholderSteeringWheelDefault;
         g_vrHandSteering = RuntimeConfigFile::kVrHandSteeringDefault;
         g_vrCockpitItemHand = 0;
         g_vrCockpitItemThrow = RuntimeConfigFile::kVrCockpitItemThrowDefault;
@@ -1776,6 +1785,7 @@ void DrawVrCameraSettings() {
         RuntimeConfigFile::SetVrCockpitUnitsPerMeter(g_vrCockpitUnitsPerMeter);
         RuntimeConfigFile::SetVrSteeringWheel(g_vrSteeringWheel);
         RuntimeConfigFile::SetVrNativeSteeringWheel(g_vrNativeSteeringWheel);
+        RuntimeConfigFile::SetVrPlaceholderSteeringWheel(g_vrPlaceholderSteeringWheel);
         RuntimeConfigFile::SetVrHandSteering(g_vrHandSteering);
         RuntimeConfigFile::SetVrCockpitItemHand(RuntimeConfigFile::kVrCockpitItemHandDefault);
         RuntimeConfigFile::SetVrCockpitItemThrow(g_vrCockpitItemThrow);

runtime/src/vr/mkw_vr_first_person.cpp

@@ -1176,9 +1176,10 @@ bool ComputeCockpitAnchorLocked(const Mtx34& view_from_world, const KartPoseRead
     return true;
 }
 
-// After the frame's draws: drop the wheel copies, and let the VR wheel stand
-// in while no draw takes them (the race's opening pan, for one). Copies keep
-// being published, so the vehicle's own wheel returns as soon as they match.
+// After the frame's draws: drop the wheel copies, and let the placeholder VR
+// wheel stand in (when enabled) while no draw takes them (the race's opening
+// pan, for one). Copies keep being published, so the vehicle's own wheel
+// returns as soon as they match.
 void FinishNativeWheelFrameLocked() noexcept {
     if (!g_state.wheel_arrays_posted) {
         return;
@@ -1206,8 +1207,11 @@ void FinishNativeWheelFrameLocked() noexcept {
             ++g_state.native_wheel_switch_logs;
             RT_LOG(RT_TAG_RUNTIME) << "[mkw-vr] native steering wheel: no draw took the animated copy of vehicle 0x"
                                    << std::hex << g_state.cockpit.body << std::dec << " in "
-                                   << kNativeWheelUnmatchedFrames
-                                   << " frames; drawing the VR steering wheel until one does" << std::endl;
+                                   << kNativeWheelUnmatchedFrames << " frames; "
+                                   << (RuntimeConfigFile::VrPlaceholderSteeringWheel()
+                                           ? "drawing the placeholder VR wheel until one does"
+                                           : "the vehicle's own is drawn as the game poses it until one does")
+                                   << std::endl;
         }
     }
 }

runtime/src/vr/openxr_input.cpp

@@ -1408,6 +1408,7 @@ void OpenXRInput::UpdateDriving(XrTime display_time, const driving::SeatFrame& s
     const bool hand_steering = RuntimeConfigFile::VrHandSteering();
     const bool steering_wheel = RuntimeConfigFile::VrSteeringWheel();
     const bool native_steering_wheel = RuntimeConfigFile::VrNativeSteeringWheel();
+    const bool placeholder_steering_wheel = RuntimeConfigFile::VrPlaceholderSteeringWheel();
     const float dt = m_wheel_time != 0 && display_time > m_wheel_time
                          ? static_cast<float>(display_time - m_wheel_time) * 1.0e-9f
                          : 1.0f / 90.0f;
@@ -1417,10 +1418,10 @@ void OpenXRInput::UpdateDriving(XrTime display_time, const driving::SeatFrame& s
     snapshot.cockpit_active = true;
     snapshot.hand_steering = hand_steering;
     snapshot.bike = anchor.bike;
-    // The vehicle's own control is the one turning (or none is shown at all),
-    // so the overlay adds no separate wheel.
-    snapshot.synthetic_control =
-        steering_wheel && !(native_steering_wheel && anchor.native_mesh_prepared);
+    // A separate wheel only when asked for and the vehicle's own is not the one
+    // turning.
+    snapshot.synthetic_control = driving::DrawsPlaceholderControl(
+        steering_wheel, native_steering_wheel, anchor.native_mesh_prepared, placeholder_steering_wheel);
 
     // Which control the hands reach for: the vehicle's own wherever its
     // geometry is known and no separate wheel is drawn, a handlebar always

runtime/tests/vr_config_tests.cpp

@@ -26,6 +26,11 @@ int main() {
     Require(Parse("[vr]\ncockpit_item_throw = false\n").vrCockpitItemThrow == false);
     Require(Parse("[vr]\ncockpit_item_throw = true\n").vrCockpitItemThrow == true);
     Require(!Parse("[vr]\n").vrCockpitItemThrow.has_value());
+    // [vr] placeholder_steering_wheel: the separate VR wheel or handlebar is opt-in.
+    Require(!RuntimeConfigFile::kVrPlaceholderSteeringWheelDefault);
+    Require(Parse("[vr]\nplaceholder_steering_wheel = true\n").vrPlaceholderSteeringWheel == true);
+    Require(Parse("[vr]\nplaceholder_steering_wheel = false\n").vrPlaceholderSteeringWheel == false);
+    Require(!Parse("[vr]\n").vrPlaceholderSteeringWheel.has_value());
     // [vr] foveation: the Quest's foveated rendering level, index-matched to
     // aurora_set_stereo_foveation.
     for (std::string_view level : RuntimeConfigFile::kVrFoveationLevels) {

runtime/tests/vr_hand_steering_tests.cpp

@@ -108,6 +108,21 @@ void TestSeatFrame() {
     CheckNear(m[11], -1.0f, "lean turns up into forward", 1e-5f);
 }
 
+void TestPlaceholderControl() {
+    // Arguments: steering_wheel, native_steering_wheel, native_mesh_prepared, placeholder.
+    Check(!driving::DrawsPlaceholderControl(true, true, false, false),
+          "no placeholder while the vehicle's own is not animated, unless asked for");
+    Check(!driving::DrawsPlaceholderControl(true, false, false, false),
+          "no placeholder with the vehicle's own wheel off, unless asked for");
+    Check(driving::DrawsPlaceholderControl(true, true, false, true),
+          "the placeholder stands in while the vehicle's own is not animated");
+    Check(driving::DrawsPlaceholderControl(true, false, true, true),
+          "the placeholder replaces the vehicle's own wheel when that is off");
+    Check(!driving::DrawsPlaceholderControl(true, true, true, true),
+          "no placeholder while the vehicle's own is the one turning");
+    Check(!driving::DrawsPlaceholderControl(false, false, false, true), "no wheel turns at all");
+}
+
 } // namespace
 
 int main() {
@@ -115,6 +130,7 @@ int main() {
     TestMaxAngle();
     TestVisual();
     TestSeatFrame();
+    TestPlaceholderControl();
     if (g_failures != 0) {
         std::cerr << g_failures << " check(s) failed\n";
         return 1;