feat: add Camera Stiffness and Pivot Height settings for motion comfort

Camera Stiffness (default 20, range 5-100): controls how tightly the
camera follows the player. Higher values = less sway/lag. Users who
experience motion sickness can increase this to reduce floaty camera.

Camera Pivot Height (default 1.8, range 0-3): height of the camera
orbit point above the player's feet. Lower values reduce the
"detached/floating" feel that can cause nausea. Setting to 0 puts the
pivot at foot level (ground-locked camera).

Both settings saved to settings file and applied via sliders in the
Gameplay tab of the Settings window.

src/rendering/camera_controller.cpp

@@ -181,7 +181,7 @@ void CameraController::update(float deltaTime) {
 
             // Pivot point at upper chest/neck
             float mountedOffset = mounted_ ? mountHeightOffset_ : 0.0f;
-            glm::vec3 pivot = targetPos + glm::vec3(0.0f, 0.0f, PIVOT_HEIGHT + mountedOffset);
+            glm::vec3 pivot = targetPos + glm::vec3(0.0f, 0.0f, pivotHeight_ + mountedOffset);
 
             // Camera direction from yaw/pitch
             glm::vec3 camDir = -forward3D;
@@ -201,7 +201,7 @@ void CameraController::update(float deltaTime) {
             if (glm::dot(smoothedCamPos, smoothedCamPos) < 1e-4f) {
                 smoothedCamPos = actualCam;
             }
-            float camLerp = 1.0f - std::exp(-CAM_SMOOTH_SPEED * deltaTime);
+            float camLerp = 1.0f - std::exp(-camSmoothSpeed_ * deltaTime);
             smoothedCamPos += (actualCam - smoothedCamPos) * camLerp;
 
             camera->setPosition(smoothedCamPos);
@@ -1450,7 +1450,7 @@ void CameraController::update(float deltaTime) {
                 if (terrainAtCam) {
                     // Keep pivot high enough so near-hill camera rays don't cut through terrain.
                     constexpr float kMinRayClearance = 2.0f;
-                    float basePivotZ = targetPos.z + PIVOT_HEIGHT + mountedOffset;
+                    float basePivotZ = targetPos.z + pivotHeight_ + mountedOffset;
                     float rayClearance = basePivotZ - *terrainAtCam;
                     if (rayClearance < kMinRayClearance) {
                         desiredLift = std::clamp(kMinRayClearance - rayClearance, 0.0f, 1.4f);
@@ -1468,7 +1468,7 @@ void CameraController::update(float deltaTime) {
             // are not relevant for camera pivoting.
             cachedPivotLift_ = 0.0f;
         }
-        glm::vec3 pivot = targetPos + glm::vec3(0.0f, 0.0f, PIVOT_HEIGHT + mountedOffset + pivotLift);
+        glm::vec3 pivot = targetPos + glm::vec3(0.0f, 0.0f, pivotHeight_ + mountedOffset + pivotLift);
 
         // Camera direction from yaw/pitch (already computed as forward3D)
         glm::vec3 camDir = -forward3D;  // Camera looks at pivot, so it's behind
@@ -1549,7 +1549,7 @@ void CameraController::update(float deltaTime) {
         if (glm::dot(smoothedCamPos, smoothedCamPos) < 1e-4f) {
             smoothedCamPos = actualCam;  // Initialize
         }
-        float camLerp = 1.0f - std::exp(-CAM_SMOOTH_SPEED * deltaTime);
+        float camLerp = 1.0f - std::exp(-camSmoothSpeed_ * deltaTime);
         smoothedCamPos += (actualCam - smoothedCamPos) * camLerp;
 
         // ===== Final floor clearance check =====
@@ -2090,7 +2090,7 @@ void CameraController::reset() {
             currentDistance = userTargetDistance;
             collisionDistance = currentDistance;
             float mountedOffset = mounted_ ? mountHeightOffset_ : 0.0f;
-            glm::vec3 pivot = spawnPos + glm::vec3(0.0f, 0.0f, PIVOT_HEIGHT + mountedOffset);
+            glm::vec3 pivot = spawnPos + glm::vec3(0.0f, 0.0f, pivotHeight_ + mountedOffset);
             glm::vec3 camDir = -forward3D;
             glm::vec3 camPos = pivot + camDir * currentDistance;
             smoothedCamPos = camPos;
@@ -2232,7 +2232,7 @@ void CameraController::reset() {
         collisionDistance = currentDistance;
 
         float mountedOffset = mounted_ ? mountHeightOffset_ : 0.0f;
-        glm::vec3 pivot = spawnPos + glm::vec3(0.0f, 0.0f, PIVOT_HEIGHT + mountedOffset);
+        glm::vec3 pivot = spawnPos + glm::vec3(0.0f, 0.0f, pivotHeight_ + mountedOffset);
         glm::vec3 camDir = -forward3D;
         glm::vec3 camPos = pivot + camDir * currentDistance;
         smoothedCamPos = camPos;
@@ -2271,7 +2271,7 @@ void CameraController::teleportTo(const glm::vec3& pos) {
         camera->setRotation(yaw, pitch);
         glm::vec3 forward3D = camera->getForward();
         float mountedOffset = mounted_ ? mountHeightOffset_ : 0.0f;
-        glm::vec3 pivot = pos + glm::vec3(0.0f, 0.0f, PIVOT_HEIGHT + mountedOffset);
+        glm::vec3 pivot = pos + glm::vec3(0.0f, 0.0f, pivotHeight_ + mountedOffset);
         glm::vec3 camDir = -forward3D;
         glm::vec3 camPos = pivot + camDir * currentDistance;
         smoothedCamPos = camPos;

src/ui/game_screen.cpp

@@ -18447,6 +18447,24 @@ if (ImGui::Checkbox("Extended Camera Zoom", &pendingExtendedZoom)) {
     }
     saveSettings();
 }
+if (ImGui::SliderFloat("Camera Stiffness", &pendingCameraStiffness, 5.0f, 100.0f, "%.0f")) {
+    if (renderer) {
+        if (auto* cameraController = renderer->getCameraController()) {
+            cameraController->setCameraSmoothSpeed(pendingCameraStiffness);
+        }
+    }
+    saveSettings();
+}
+ImGui::SetItemTooltip("Higher = tighter camera with less sway. Default: 20");
+if (ImGui::SliderFloat("Camera Pivot Height", &pendingPivotHeight, 0.0f, 3.0f, "%.1f")) {
+    if (renderer) {
+        if (auto* cameraController = renderer->getCameraController()) {
+            cameraController->setPivotHeight(pendingPivotHeight);
+        }
+    }
+    saveSettings();
+}
+ImGui::SetItemTooltip("Height of camera orbit point above feet. Lower = less detached feel. Default: 1.8");
 if (ImGui::IsItemHovered())
     ImGui::SetTooltip("Allow the camera to zoom out further than normal");
 
@@ -21294,6 +21312,8 @@ void GameScreen::saveSettings() {
     out << "mouse_sensitivity=" << pendingMouseSensitivity << "\n";
     out << "invert_mouse=" << (pendingInvertMouse ? 1 : 0) << "\n";
     out << "extended_zoom=" << (pendingExtendedZoom ? 1 : 0) << "\n";
+    out << "camera_stiffness=" << pendingCameraStiffness << "\n";
+    out << "camera_pivot_height=" << pendingPivotHeight << "\n";
     out << "fov=" << pendingFov << "\n";
 
     // Quest tracker position/size
@@ -21452,6 +21472,8 @@ void GameScreen::loadSettings() {
             else if (key == "mouse_sensitivity") pendingMouseSensitivity = std::clamp(std::stof(val), 0.05f, 1.0f);
             else if (key == "invert_mouse") pendingInvertMouse = (std::stoi(val) != 0);
             else if (key == "extended_zoom") pendingExtendedZoom = (std::stoi(val) != 0);
+            else if (key == "camera_stiffness") pendingCameraStiffness = std::clamp(std::stof(val), 5.0f, 100.0f);
+            else if (key == "camera_pivot_height") pendingPivotHeight = std::clamp(std::stof(val), 0.0f, 3.0f);
             else if (key == "fov") {
                 pendingFov = std::clamp(std::stof(val), 45.0f, 110.0f);
                 if (auto* renderer = core::Application::getInstance().getRenderer()) {