1 files changed, 100 insertions, 0 deletions
diff --git a/src/Fl_Valuator.cxx b/src/Fl_Valuator.cxx
new file mode 100644
index 000000000..a39513c37
--- /dev/null
+++ b/src/Fl_Valuator.cxx
@@ -0,0 +1,100 @@
+// Fl_Valuator.C
+
+// Base class for sliders and all other one-value "knobs"
+
+#include <FL/Fl.H>
+#include <FL/Fl_Valuator.H>
+#include <FL/math.h>
+#include <stdio.h>
+
+Fl_Valuator::Fl_Valuator(int X, int Y, int W, int H, const char* L)
+  : Fl_Widget(X,Y,W,H,L) {
+  align(FL_ALIGN_BOTTOM);
+  when(FL_WHEN_CHANGED);
+  value_ = 0;
+  min = 0;
+  max = 1;
+  A = 0.0;
+  B = 1;
+}
+
+const double epsilon = 1e-12 ;
+
+void Fl_Valuator::step(double s) {
+  if (s < 0) s = -s;
+  A = rint(s);
+  B = 1;
+  while (fabs(s-A/B) > epsilon) {B *= 10; A = rint(s*B);}
+}
+
+void Fl_Valuator::precision(int p) {
+  A = 1.0;
+  for (B = 1; p--;) B *= 10;
+}
+
+void Fl_Valuator::value_damage() {damage(2);} // by default do partial-redraw
+
+int Fl_Valuator::value(double v) {
+  clear_changed();
+  if (v == value_) return 0;
+  value_ = v;
+  value_damage();
+  return 1;
+}
+
+double Fl_Valuator::softclamp(double v) {
+  int which = (min<=max);
+  double p = previous_value_;
+  if ((v<min)==which && p!=min && (p<min)!=which) return min;
+  else if ((v>max)==which && p!=max && (p>max)!=which) return max;
+  else return v;
+}
+
+// inline void Fl_Valuator::handle_push() {previous_value_ = value_;}
+
+void Fl_Valuator::handle_drag(double v) {
+  if (v != value_) {
+    value_ = v;
+    value_damage();
+    if (when() & FL_WHEN_CHANGED) do_callback();
+    else set_changed();
+  }
+}
+
+void Fl_Valuator::handle_release() {
+  if (when()&FL_WHEN_RELEASE) {
+    // insure changed() is off even if no callback is done.  It may have
+    // been turned on by the drag, and then the slider returned to it's
+    // initial position:
+    clear_changed();
+    // now do the callback only if slider in new position or always is on:
+    if (value_ != previous_value_ || when() & FL_WHEN_NOT_CHANGED)
+      do_callback();
+  }
+}
+
+double Fl_Valuator::round(double v) {
+  if (A) return rint(v*B/A)*A/B;
+  else return v;
+}
+
+double Fl_Valuator::clamp(double v) {
+  if ((v<min)==(min<=max)) return min;
+  else if ((v>max)==(min<=max)) return max;
+  else return v;
+}
+
+double Fl_Valuator::increment(double v, int n) {
+  if (!A) return v+n*(max-min)/100;
+  if (min > max) n = -n;
+  return (rint(v*B/A)+n)*A/B;
+}
+
+int Fl_Valuator::format(char* buffer) {
+  double v = value();
+  if (!A || B==1) return sprintf(buffer, "%g", v);
+  int i, x;
+  for (x = 10, i = 2; x < B; x *= 10) i++;
+  if (x == B) i--;
+  return sprintf(buffer, "%.*f", i, v);
+}