Properly account for margins in sliders

[libs/gltk.git] / source / slider.cpp

diff --git a/source/slider.cpp b/source/slider.cpp
index 15621db5b9b06e8035523cf2a479d3549ab7e587..1e763c639bf5309fba69d3a3ce3e680aba97eff1 100644 (file)
--- a/source/slider.cpp
+++ b/source/slider.cpp
@@ -10,6 +10,7 @@ Slider::Slider():
        step(0.1),
        dragging(false),
        drag_area_size(0),
+       drag_area_offset(0),
        slider_size(1)
 { }
 
@@ -49,13 +50,17 @@ void Slider::set_step(double s)
 
 void Slider::click(int p)
 {
-       int sp = static_cast<int>(drag_area_size*(value-min)/(max-min));
+       p -= drag_area_offset;
+       if(p<0 || p>=static_cast<int>(drag_area_size))
+               return;
+
+       int sp = static_cast<int>((drag_area_size-slider_size)*(value-min)/(max-min));
        if(p<sp)
                set_value(value-step*10);
        else if(p>=static_cast<int>(sp+slider_size))
                set_value(value+step*10);
        else
-               start_drag(p);
+               start_drag(drag_area_offset+p);
 }
 
 void Slider::start_drag(int p)
@@ -69,7 +74,7 @@ void Slider::start_drag(int p)
 void Slider::drag(int p)
 {
        if(max>min)
-               set_value(drag_start_value+(p-drag_start_pos)*(max-min)/drag_area_size);
+               set_value(drag_start_value+(p-drag_start_pos)*(max-min)/(drag_area_size-slider_size));
 }
 
 void Slider::end_drag()