When clicking the value slider bar, the knob was not positioned as
close to the mouse as expected. When moving the mouse right, the knob
would lag a bit behind, and the cursor would eventually be outside the
knob.
The bug was due to knob_rect() taking knob_thickness into account to
prevent the knob from protruding outside the bar. The value_at(pos)
calculated the relative position based on the entire width of the bar.
This discrepancy is fixed by taking knob_thickness into account in
value_at(position).
When dragging value slider left, the handle would snap to lower value
with the slightest move of the mouse. When dragging to the right
however, it would take a lot more movement to cause a change in value.
This asymmetry made it feel awkward to drag the mouse around. It was
caused by always rounding down using a cast to int. By rounding to the
nearest integer first, we ensure symmetric behavior.
We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
This patch fixes a value glitch when changing the slider value via
dragging the knob with the mouse and having a min value smaller than 0.
Before this patch it was not possible to drag the value below 0 and it
just snapped to the configured min value if the mouse was at the most
left position. Now the value is calculated from the value range and
mouse position within the widget.
This is a helpful option to prevent unwanted side effects, distinguish
between user and programmatic input, etc. Sliders and SpinBoxes were
implementing it idiosyncratically, so let's generalize the API and
give Buttons and TextEditors the same ability.
ValueSlider is a more generalized version of OpacitySlider when we need
a slider with values displayed. It will always show the current value
with a user defined suffix.
