Issue #123: implement turntable mouse navigation

src/confscreen.cpp

@@ -84,6 +84,23 @@ void TextWindow::ScreenChangeBackFaces(int link, uint32_t v) {
     InvalidateGraphics();
 }
 
+void TextWindow::ScreenChangeTurntableNav(int link, uint32_t v) {
+    SS.turntableNav = !SS.turntableNav;
+
+    // if turntable nav is being toggled to ON, align view so Z is vertical
+    if(SS.turntableNav) {
+        SS.GW.AnimateOnto(
+            Quaternion::From(
+                Vector::From(1,0,0),
+                Vector::From(0,1,0)
+            ),
+            SS.GW.offset
+        );
+    }
+
+    InvalidateGraphics(); // not sure if this is needed after the AnimateOnto, but hey
+}
+
 void TextWindow::ScreenChangeCheckClosedContour(int link, uint32_t v) {
     SS.checkClosedContour = !SS.checkClosedContour;
     InvalidateGraphics();
@@ -297,6 +314,9 @@ void TextWindow::ShowConfiguration() {
     Printf(false, "  %Fd%f%Ll%s  check sketch for closed contour%E",
         &ScreenChangeCheckClosedContour,
         SS.checkClosedContour ? CHECK_TRUE : CHECK_FALSE);
+    Printf(false, "  %Fd%f%Ll%s  use turntable mouse navigation%E",
+        &ScreenChangeTurntableNav,
+        SS.turntableNav ? CHECK_TRUE : CHECK_FALSE);
 
     Printf(false, "");
     Printf(false, "%Ft autosave interval (in minutes)%E");

src/mouse.cpp

@@ -129,8 +129,16 @@ void GraphicsWindow::MouseMoved(double x, double y, bool leftDown,
 
         if(!(shiftDown || ctrlDown)) {
             double s = 0.3*(PI/180)*scale; // degrees per pixel
-            projRight = orig.projRight.RotatedAbout(orig.projUp, -s*dx);
-            projUp = orig.projUp.RotatedAbout(orig.projRight, s*dy);
+            if(SS.turntableNav) {
+                projRight = orig.projRight.RotatedAbout(Vector::From(0, 1, 0), -s*dx);
+                projUp = orig.projUp.RotatedAbout( // lock the Z to vertical
+                    Vector::From(orig.projRight.x, orig.projRight.y, 0),
+                    s*dy
+                );
+            } else {
+                projRight = orig.projRight.RotatedAbout(orig.projUp, -s*dx);
+                projUp = orig.projUp.RotatedAbout(orig.projRight, s*dy);
+            }
 
             NormalizeProjectionVectors();
         } else if(ctrlDown) {

src/solvespace.cpp

@@ -70,6 +70,8 @@ void SolveSpaceUI::Init() {
     drawBackFaces = CnfThawBool(true, "DrawBackFaces");
     // Check that contours are closed and not self-intersecting
     checkClosedContour = CnfThawBool(true, "CheckClosedContour");
+    // Use turntable mouse navigation
+    turntableNav = CnfThawBool(false, "TurntableNav");
     // Export shaded triangles in a 2d view
     exportShadedTriangles = CnfThawBool(true, "ExportShadedTriangles");
     // Export pwl curves (instead of exact) always
@@ -188,6 +190,8 @@ void SolveSpaceUI::Exit() {
     CnfFreezeBool(drawBackFaces, "DrawBackFaces");
     // Check that contours are closed and not self-intersecting
     CnfFreezeBool(checkClosedContour, "CheckClosedContour");
+    // Use turntable mouse navigation
+    CnfFreezeBool(turntableNav, "TurntableNav");
     // Export shaded triangles in a 2d view
     CnfFreezeBool(exportShadedTriangles, "ExportShadedTriangles");
     // Export pwl curves (instead of exact) always

src/solvespace.h

@@ -463,7 +463,7 @@ class StepFileWriter {
 public:
     void ExportSurfacesTo(const std::string &filename);
     void WriteHeader();
-	void WriteProductHeader();
+    void WriteProductHeader();
     int ExportCurve(SBezier *sb);
     int ExportCurveLoop(SBezierLoop *loop, bool inner);
     void ExportSurface(SSurface *ss, SBezierList *sbl);
@@ -723,6 +723,7 @@ class SolveSpaceUI {
     bool     fixExportColors;
     bool     drawBackFaces;
     bool     checkClosedContour;
+    bool     turntableNav;
     bool     showToolbar;
     RgbaColor backgroundColor;
     bool     exportShadedTriangles;
@@ -804,7 +805,7 @@ class SolveSpaceUI {
         Style        s;
     } sv;
     static void MenuFile(Command id);
-	bool Autosave();
+    bool Autosave();
     void RemoveAutosave();
     bool GetFilenameAndSave(bool saveAs);
     bool OkayToStartNewFile();

src/ui.h

@@ -410,6 +410,7 @@ class TextWindow {
     static void ScreenChangeFixExportColors(int link, uint32_t v);
     static void ScreenChangeBackFaces(int link, uint32_t v);
     static void ScreenChangeCheckClosedContour(int link, uint32_t v);
+    static void ScreenChangeTurntableNav(int link, uint32_t v);
     static void ScreenChangePwlCurves(int link, uint32_t v);
     static void ScreenChangeCanvasSizeAuto(int link, uint32_t v);
     static void ScreenChangeCanvasSize(int link, uint32_t v);