Control key modifier enables alternate zoom method.

WickedSmoke · WickedSmoke · commit ed62f12f04e3 · 2025-03-01T20:21:54.000-05:00
NOTE: Currently only works with mouse wheel as key input is routed through
GraphicsWindow::MenuView().
diff --git a/src/graphicswin.cpp b/src/graphicswin.cpp
@@ -724,14 +724,14 @@ double GraphicsWindow::ZoomToFit(const Camera &camera,
 }
 
 
-void GraphicsWindow::ZoomToMouse(double zoomMultiplyer) {
+void GraphicsWindow::ZoomToMouse(double zoomMultiplyer, bool centered) {
     double offsetRight, offsetUp;
     double righti, upi;
 
     // Mouse edit operations currently track the pointer relative to the
-    // initial button press position, so zoomCenterNav is ignored during edits.
-    bool trackPointer = (pending.operation != Pending::NONE) ||
-                        (! SS.zoomCenterNav);
+    // initial button press position, so centered is currently ignored during
+    // edits.
+    bool trackPointer = (pending.operation != Pending::NONE) || (! centered);
 
     if (trackPointer) {
         offsetRight = offset.Dot(projRight);
@@ -771,11 +771,11 @@ void GraphicsWindow::ZoomToMouse(double zoomMultiplyer) {
 void GraphicsWindow::MenuView(Command id) {
     switch(id) {
         case Command::ZOOM_IN:
-            SS.GW.ZoomToMouse(1);
+            SS.GW.ZoomToMouse(1, SS.zoomCenterNav);
             break;
 
         case Command::ZOOM_OUT:
-            SS.GW.ZoomToMouse(-1);
+            SS.GW.ZoomToMouse(-1, SS.zoomCenterNav);
             break;
 
         case Command::ZOOM_TO_FIT:
diff --git a/src/mouse.cpp b/src/mouse.cpp
@@ -915,7 +915,8 @@ bool GraphicsWindow::MouseEvent(Platform::MouseEvent event) {
             break;
 
         case MouseEvent::Type::SCROLL_VERT:
-            this->MouseScroll(event.shiftDown ? event.scrollDelta / 10 : event.scrollDelta);
+            this->MouseScroll(event.shiftDown ? event.scrollDelta / 10 : event.scrollDelta,
+                              event.controlDown);
             break;
 
         case MouseEvent::Type::LEAVE:
@@ -1480,7 +1481,7 @@ void GraphicsWindow::EditControlDone(const std::string &s) {
     }
 }
 
-void GraphicsWindow::MouseScroll(double zoomMultiplyer) {
+void GraphicsWindow::MouseScroll(double zoomMultiplyer, bool alt) {
     // To support smooth scrolling where scroll wheel events come in increments
     // smaller (or larger) than 1 we do:
     //     scale *= exp(ln(1.2) * zoomMultiplyer);
@@ -1491,7 +1492,7 @@ void GraphicsWindow::MouseScroll(double zoomMultiplyer) {
     // while
     //     scale * a * b != scale * (a+b)
     // So this constant is ln(1.2) = 0.1823216 to make the default zoom 1.2x
-    ZoomToMouse(zoomMultiplyer);
+    ZoomToMouse(zoomMultiplyer, alt ? ! SS.zoomCenterNav : SS.zoomCenterNav);
 }
 
 void GraphicsWindow::MouseLeave() {
diff --git a/src/ui.h b/src/ui.h
@@ -629,7 +629,7 @@ class GraphicsWindow {
     void HandlePointForZoomToFit(Vector p, Point2d *pmax, Point2d *pmin,
                                  double *wmin, bool usePerspective,
                                  const Camera &camera);
-    void ZoomToMouse(double delta);
+    void ZoomToMouse(double delta, bool centered);
     void LoopOverPoints(const std::vector<Entity *> &entities,
                         const std::vector<Constraint *> &constraints,
                         const std::vector<hEntity> &faces,
@@ -855,7 +855,7 @@ class GraphicsWindow {
     void MouseLeftDoubleClick(double x, double y);
     void MouseMiddleOrRightDown(double x, double y);
     void MouseRightUp(double x, double y);
-    void MouseScroll(double delta);
+    void MouseScroll(double delta, bool alt);
     void MouseLeave();
     bool KeyboardEvent(Platform::KeyboardEvent event);
     void EditControlDone(const std::string &s);
