spline-widget: simplify/fix drawing logic

The linear things should be drawn in drawFunction() since they
change only when some control point is moved and the spline is
recalculated anyway.

Introduce spline::get_value_no_save to avoid clobbering the
tracked value.

Draw linear helper before the spline to avoid occluding it.

Remove some redundant checks for whether _config exists when all
calling sites ensure it already.

I still need to de-camel-case these two classes.

1 files changed, 4 insertions, 15 deletions

diff --git a/spline-widget/spline-widget.hpp b/spline-widget/spline-widget.hpp
index 477e3ba6..d94d2e8e 100644
--- a/spline-widget/spline-widget.hpp
+++ b/spline-widget/spline-widget.hpp
@@ -39,23 +39,12 @@ public:
     ~spline_widget();
 
     spline* config();
-
     void setConfig(spline* spl);
 
-    QColor colorBezier() const
-    {
-        return spline_color;
-    }
-    void setColorBezier(QColor color)
-    {
-        spline_color = color;
-        update();
-    }
-    void force_redraw()
-    {
-        _background = QPixmap();
-        update();
-    }
+    QColor colorBezier() const;
+    void setColorBezier(QColor color);
+
+    void force_redraw();
     void set_preview_only(bool val);
     bool is_preview_only() const;
     void set_snap(double x, double y) { snap_x = x; snap_y = y; }