Updated Fl_Dial to use atan2() to avoid possible math errors and reduce

code size. git-svn-id: file:///fltk/svn/fltk/trunk@277 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
fltk · Feb 16, 1999 · 18312d3 · 18312d3
1 parent 7b82bc3
commit 18312d3
Showing 1 changed file with 3 additions and 11 deletions.
diff --git a/src/Fl_Dial.cxx b/src/Fl_Dial.cxx
@@ -1,5 +1,5 @@
 //
-// "$Id: Fl_Dial.cxx,v 1.5 1999/01/07 19:17:19 mike Exp $"
+// "$Id: Fl_Dial.cxx,v 1.6 1999/02/16 17:23:55 mike Exp $"
 //
 // Circular dial widget for the Fast Light Tool Kit (FLTK).
 //
@@ -101,15 +101,7 @@ int Fl_Dial::handle(int event, int x, int y, int w, int h) {
     int mx = Fl::event_x()-x-w/2;
     int my = Fl::event_y()-y-h/2;
     if (!mx && !my) return 1;
-    if (abs(mx) > abs(my)) {
-      angle = atan(-(double)my/mx);
-      if (mx>0) angle = 1.25*M_PI - angle;
-      else angle = 0.25*M_PI - angle;
-    } else {
-      angle = atan(-(double)mx/my);
-      if (my<0) angle = 0.75*M_PI + angle;
-      else angle = -0.25*M_PI + angle;
-    }
+    angle = atan2(-my, -mx) + 0.25 * M_PI;
     if (angle<(-0.25*M_PI)) angle += 2.0*M_PI;
     val = minimum() + (maximum()-minimum())*angle/(1.5*M_PI);
     if (fabs(val-value()) < (maximum()-minimum())/2.0)
@@ -134,5 +126,5 @@ Fl_Dial::Fl_Dial(int x, int y, int w, int h, const char* l)
 }
 
 //
-// End of "$Id: Fl_Dial.cxx,v 1.5 1999/01/07 19:17:19 mike Exp $".
+// End of "$Id: Fl_Dial.cxx,v 1.6 1999/02/16 17:23:55 mike Exp $".
 //