Configurable navigation bindings

src/ifcviewer/AppSettings.cpp

@@ -42,6 +42,7 @@ constexpr const char* kHizResolutionKey = "viewport/hiz_resolution";
 constexpr int kHizResolutionDefault = 256;
 constexpr int kHizResolutionFloor = 64;
 constexpr const char* kHizEnabledKey = "viewport/hiz_enabled";
+constexpr const char* kNavPresetKey = "viewport/nav_preset";
 }
 
 AppSettings& AppSettings::instance() {
@@ -181,6 +182,17 @@ void AppSettings::setHizEnabled(bool value) {
     emit hizEnabledChanged(value);
 }
 
+AppSettings::NavPreset AppSettings::navPreset() const {
+    return nav_preset_;
+}
+
+void AppSettings::setNavPreset(NavPreset value) {
+    if (nav_preset_ == value) return;
+    nav_preset_ = value;
+    persist();
+    emit navPresetChanged(value);
+}
+
 void AppSettings::load() {
     QSettings settings;
     geometry_library_ = settings.value(kGeometryLibraryKey, kGeometryLibraryDefault).toString();
@@ -203,6 +215,17 @@ void AppSettings::load() {
     hiz_resolution_ = settings.value(kHizResolutionKey, kHizResolutionDefault).toInt();
     if (hiz_resolution_ < kHizResolutionFloor) hiz_resolution_ = kHizResolutionFloor;
     hiz_enabled_ = settings.value(kHizEnabledKey, true).toBool();
+    {
+        const int raw = settings.value(kNavPresetKey,
+                                       static_cast<int>(NavPreset::Blender)).toInt();
+        // Clamp to known values so a stale config doesn't drop us into
+        // an undefined preset slot.
+        if (raw < 0 || raw > static_cast<int>(NavPreset::Revit)) {
+            nav_preset_ = NavPreset::Blender;
+        } else {
+            nav_preset_ = static_cast<NavPreset>(raw);
+        }
+    }
 }
 
 void AppSettings::persist() {
@@ -218,4 +241,5 @@ void AppSettings::persist() {
     settings.setValue(kLod1PixelThresholdKey, lod1_pixel_threshold_);
     settings.setValue(kHizResolutionKey, hiz_resolution_);
     settings.setValue(kHizEnabledKey, hiz_enabled_);
+    settings.setValue(kNavPresetKey, static_cast<int>(nav_preset_));
 }

src/ifcviewer/AppSettings.h

@@ -29,6 +29,21 @@
 class AppSettings : public QObject {
     Q_OBJECT
 public:
+    // Navigation preset.  Selects which mouse button (+ optional Shift)
+    // drives orbit and pan.  Selection is unaffected and stays on LMB
+    // for every preset — these three intentionally don't take LMB so
+    // click + box-select remain available without modifier gymnastics.
+    //
+    //   Blender   — Orbit MMB,        Pan Shift+MMB   (current default)
+    //   Rhino     — Orbit RMB,        Pan Shift+RMB
+    //   Revit     — Orbit Shift+MMB,  Pan MMB
+    enum class NavPreset {
+        Blender = 0,
+        Rhino   = 1,
+        Revit   = 2,
+    };
+    Q_ENUM(NavPreset)
+
     static AppSettings& instance();
 
     QString geometryLibrary() const;
@@ -89,6 +104,10 @@ public:
     bool hizEnabled() const;
     void setHizEnabled(bool value);
 
+    // Navigation preset (see NavPreset enum above).
+    NavPreset navPreset() const;
+    void setNavPreset(NavPreset value);
+
 signals:
     void geometryLibraryChanged(const QString& value);
     void showStatsChanged(bool value);
@@ -101,6 +120,7 @@ signals:
     void lod1PixelThresholdChanged(double value);
     void hizResolutionChanged(int value);
     void hizEnabledChanged(bool value);
+    void navPresetChanged(NavPreset value);
 
 private:
     AppSettings();
@@ -118,6 +138,7 @@ private:
     double lod1_pixel_threshold_ = 30.0;
     int hiz_resolution_ = 256;
     bool hiz_enabled_ = true;
+    NavPreset nav_preset_ = NavPreset::Blender;
 };
 
 #endif // APPSETTINGS_H

src/ifcviewer/ViewportWindow.cpp

@@ -3572,9 +3572,17 @@ void ViewportWindow::handleMousePress(QMouseEvent* e) {
     box_select_armed_       = false;
     box_select_active_      = false;
     press_pick_id_          = 0;
-    if (e->button() == Qt::MiddleButton) {
-        setPivotIndicatorVisible(true);
-        requestUpdate();
+    // Show the pivot indicator while the user holds the navigation
+    // button(s) for the active preset — Blender uses MMB for both
+    // orbit + pan, Revit too (with Shift swapping the role), Rhino
+    // uses RMB.  Either way, the press of that button is what the
+    // user means as "I'm about to navigate".
+    {
+        const NavBindings nb = currentNavBindings();
+        if (e->button() == nb.orbit_button || e->button() == nb.pan_button) {
+            setPivotIndicatorVisible(true);
+            requestUpdate();
+        }
     }
     if (section_tool_active_ && e->button() == Qt::LeftButton) {
         // First try to grab an existing plane's arrow gizmo.
@@ -3684,7 +3692,9 @@ void ViewportWindow::handleMouseRelease(QMouseEvent* e) {
         press_pick_id_     = 0;
     }
 
-    const bool was_navigating = (active_button_ == Qt::MiddleButton);
+    const NavBindings nb = currentNavBindings();
+    const bool was_navigating =
+        (active_button_ == nb.orbit_button || active_button_ == nb.pan_button);
     active_button_ = Qt::NoButton;
     if (was_navigating && pivot_indicator_visible_) {
         setPivotIndicatorVisible(false);
@@ -3749,26 +3759,40 @@ void ViewportWindow::handleMouseMove(QMouseEvent* e) {
 
     QPoint delta = e->pos() - last_mouse_pos_;
     last_mouse_pos_ = e->pos();
-    if (active_button_ == Qt::MiddleButton) {
-        if (e->modifiers() & Qt::ShiftModifier) {
-            const float pan_speed = camera_distance_ * 0.002f;
-            // Derive screen-right and screen-up from the actual camera basis
-            // rather than yaw/pitch alone — the latter assumed up = world +Z,
-            // which breaks at top/bottom views where updateCamera switches
-            // the lookAt up vector to world +Y.
-            const QVector3D forward = (camera_target_ - camera_eye_).normalized();
-            const QVector3D up_ref = (std::abs(camera_pitch_) >= 89.0f)
-                                   ? QVector3D(0, 1, 0)
-                                   : QVector3D(0, 0, 1);
-            const QVector3D right = QVector3D::crossProduct(forward, up_ref).normalized();
-            const QVector3D up    = QVector3D::crossProduct(right, forward).normalized();
-            camera_target_ -= right * delta.x() * pan_speed;
-            camera_target_ += up    * delta.y() * pan_speed;
-        } else {
-            camera_yaw_ -= delta.x() * 0.3f;
-            camera_pitch_ += delta.y() * 0.3f;
-            camera_pitch_ = qBound(-89.0f, camera_pitch_, 89.0f);
-        }
+
+    // Dispatch nav drag against the active preset.  Modifier matching
+    // is exact on the Shift bit only — the only modifier any of our
+    // presets uses — so toggling Shift mid-drag flips between orbit
+    // and pan when both share a button (Blender / Revit).
+    const NavBindings nb = currentNavBindings();
+    const bool shift_now      = (e->modifiers() & Qt::ShiftModifier) != 0;
+    const bool shift_for_pan  = (nb.pan_mods   & Qt::ShiftModifier) != 0;
+    const bool shift_for_orb  = (nb.orbit_mods & Qt::ShiftModifier) != 0;
+    const bool is_pan   = (active_button_ == nb.pan_button)
+                       && (shift_now == shift_for_pan);
+    const bool is_orbit = !is_pan
+                       && (active_button_ == nb.orbit_button)
+                       && (shift_now == shift_for_orb);
+
+    if (is_pan) {
+        const float pan_speed = camera_distance_ * 0.002f;
+        // Derive screen-right and screen-up from the actual camera basis
+        // rather than yaw/pitch alone — the latter assumed up = world +Z,
+        // which breaks at top/bottom views where updateCamera switches
+        // the lookAt up vector to world +Y.
+        const QVector3D forward = (camera_target_ - camera_eye_).normalized();
+        const QVector3D up_ref = (std::abs(camera_pitch_) >= 89.0f)
+                               ? QVector3D(0, 1, 0)
+                               : QVector3D(0, 0, 1);
+        const QVector3D right = QVector3D::crossProduct(forward, up_ref).normalized();
+        const QVector3D up    = QVector3D::crossProduct(right, forward).normalized();
+        camera_target_ -= right * delta.x() * pan_speed;
+        camera_target_ += up    * delta.y() * pan_speed;
+        requestUpdate();
+    } else if (is_orbit) {
+        camera_yaw_ -= delta.x() * 0.3f;
+        camera_pitch_ += delta.y() * 0.3f;
+        camera_pitch_ = qBound(-89.0f, camera_pitch_, 89.0f);
         requestUpdate();
     }
 }
@@ -4249,6 +4273,25 @@ void ViewportWindow::toggleVolumeTool() {
     setToolMode(tool_mode_ == ToolMode::Volume ? ToolMode::None : ToolMode::Volume);
 }
 
+ViewportWindow::NavBindings ViewportWindow::currentNavBindings() const {
+    using NP = AppSettings::NavPreset;
+    switch (AppSettings::instance().navPreset()) {
+    case NP::Rhino:
+        // Orbit RMB,        Pan Shift+RMB.
+        return { Qt::RightButton,  Qt::NoModifier,
+                 Qt::RightButton,  Qt::ShiftModifier };
+    case NP::Revit:
+        // Orbit Shift+MMB,  Pan MMB.
+        return { Qt::MiddleButton, Qt::ShiftModifier,
+                 Qt::MiddleButton, Qt::NoModifier };
+    case NP::Blender:
+    default:
+        // Orbit MMB,        Pan Shift+MMB.
+        return { Qt::MiddleButton, Qt::NoModifier,
+                 Qt::MiddleButton, Qt::ShiftModifier };
+    }
+}
+
 void ViewportWindow::setHighlightTriangles(const std::vector<float>& world_xyz,
                                             float r, float g, float b, float a) {
     if (!gl_initialized_) return;

src/ifcviewer/ViewportWindow.h

@@ -431,6 +431,17 @@ protected:
     bool event(QEvent* event) override;
 
 private:
+    // Resolved mouse-binding for the active AppSettings::NavPreset.
+    // Selection always stays on LMB; only orbit and pan move around
+    // (presets are picked so neither lands on plain LMB).
+    struct NavBindings {
+        Qt::MouseButton       orbit_button;
+        Qt::KeyboardModifiers orbit_mods;
+        Qt::MouseButton       pan_button;
+        Qt::KeyboardModifiers pan_mods;
+    };
+    NavBindings currentNavBindings() const;
+
     enum class PendingOpType {
         UploadMeshChunk,
         UploadInstanceChunk,