Changed GetMilliseconds() to return a 64-bit value

This function previously returned an int32_t. Presuming that it measures
the length of time since the application was started, the 32-bit type would
cause the returned value to wrap from 2^31-1 to -2^31 after a little less
than twenty-five days.

generate.cpp

@@ -179,13 +179,13 @@ void SolveSpace::GenerateAll(int first, int last, bool andFindFree) {
     SK.param.MoveSelfInto(&prev);
     SK.entity.Clear();
 
-    int32_t inTime = GetMilliseconds();
+    int64_t inTime = GetMilliseconds();
 
     bool displayedStatusMessage = false;
     for(i = 0; i < SK.group.n; i++) {
         Group *g = &(SK.group.elem[i]);
 
-        int32_t now = GetMilliseconds();
+        int64_t now = GetMilliseconds();
         // Display the status message if we've taken more than 400 ms, or
         // if we've taken 200 ms but we're not even halfway done, or if
         // we've already started displaying the status message.

graphicswin.cpp

@@ -263,7 +263,7 @@ void GraphicsWindow::AnimateOnto(Quaternion quatf, Vector offsetf) {
     // long translations (as measured in pixels) if the user zooms out, moves,
     // and then zooms in again.
     if(dt > 2000) dt = 2000;
-    int32_t tn, t0 = GetMilliseconds();
+    int64_t tn, t0 = GetMilliseconds();
     double s = 0;
     Quaternion dq = quatf.Times(quat0.Inverse());
     do {

mouse.cpp

@@ -1291,7 +1291,7 @@ void GraphicsWindow::SpaceNavigatorMoved(double tx, double ty, double tz,
         // If we go five seconds without SpaceNavigator input, or if we've
         // switched groups, then consider that a new action and save an undo
         // point.
-        int32_t now = GetMilliseconds();
+        int64_t now = GetMilliseconds();
         if(now - lastSpaceNavigatorTime > 5000 ||
            lastSpaceNavigatorGroup.v != g->h.v)
         {

solvespace.h

@@ -208,7 +208,7 @@ void ToggleFullScreen(void);
 bool FullScreenIsActive(void);
 void GetGraphicsWindowSize(int *w, int *h);
 void GetTextWindowSize(int *w, int *h);
-int32_t GetMilliseconds(void);
+int64_t GetMilliseconds(void);
 int64_t GetUnixTime(void);
 
 void dbp(const char *str, ...);

srf/triangulate.cpp

@@ -11,7 +11,7 @@
 void SPolygon::UvTriangulateInto(SMesh *m, SSurface *srf) {
     if(l.n <= 0) return;
 
-    int32_t in = GetMilliseconds();
+    //int64_t in = GetMilliseconds();
 
     normal = Vector::From(0, 0, 1);
 
@@ -67,7 +67,7 @@ void SPolygon::UvTriangulateInto(SMesh *m, SSurface *srf) {
             }
         }
 
-//        dbp("finished finding holes: %d ms", GetMilliseconds() - in);
+//        dbp("finished finding holes: %d ms", (int)(GetMilliseconds() - in));
         for(;;) {
             double xmin = 1e10;
             SContour *scmin = NULL;
@@ -86,13 +86,13 @@ void SPolygon::UvTriangulateInto(SMesh *m, SSurface *srf) {
                 dbp("couldn't merge our hole");
                 return;
             }
-//            dbp("   bridged to contour: %d ms", GetMilliseconds() - in);
+//            dbp("   bridged to contour: %d ms", (int)(GetMilliseconds() - in));
             scmin->tag = 3;
         }
-//        dbp("finished merging holes: %d ms", GetMilliseconds() - in);
+//        dbp("finished merging holes: %d ms", (int)(GetMilliseconds() - in));
 
         merged.UvTriangulateInto(m, srf);
-//        dbp("finished ear clippping: %d ms", GetMilliseconds() - in);
+//        dbp("finished ear clippping: %d ms", (int)(GetMilliseconds() - in));
         merged.l.Clear();
         el.Clear();
         vl.Clear();

ui.h

@@ -636,7 +636,7 @@ public:
         CMNU_FIRST_STYLE      = 0x40000000
     };
     void ContextMenuListStyles(void);
-    int32_t contextMenuCancelTime;
+    int64_t contextMenuCancelTime;
 
     // The toolbar, in toolbar.cpp
     bool ToolbarDrawOrHitTest(int x, int y, bool paint, int *menuHit);
@@ -683,7 +683,7 @@ public:
     bool KeyDown(int c);
     void EditControlDone(const char *s);
 
-    int32_t lastSpaceNavigatorTime;
+    int64_t lastSpaceNavigatorTime;
     hGroup lastSpaceNavigatorGroup;
     void SpaceNavigatorMoved(double tx, double ty, double tz,
                              double rx, double ry, double rz, bool shiftDown);

win32/w32main.cpp

@@ -660,13 +660,13 @@ bool FullScreenIsActive(void)
     return false;
 }
 
-int32_t GetMilliseconds(void)
+int64_t GetMilliseconds(void)
 {
     LARGE_INTEGER t, f;
     QueryPerformanceCounter(&t);
     QueryPerformanceFrequency(&f);
     LONGLONG d = t.QuadPart/(f.QuadPart/1000);
-    return (int32_t)d;
+    return (int64_t)d;
 }
 
 int64_t GetUnixTime(void)