I’m implementing some range sliders as Sliders of style TwoValueVertical in JUCE (v. 1.46). Their values are upside-down with respect to their one-valued counterparts. It seems that changing the relevant lines in Slider::getLinearSliderPos,
if (style == LinearVertical || style == IncDecButtons)
sliderPosProportional = 1.0 - sliderPosProportional;
to ask if a slider isVertical(), could fix this. As always, there may be a good reason for the existing behavior that I’m missing, or the change may simply break existing apps by now, in which case I hope there can be an option to invert them.