Mirror the color wheel innards

To make the color wheel look like it does in most other software,
ascending least saturated to most saturated, instead of the other way
round. The descending variant can be toggled in the preferences.

ChangeLog

@@ -21,6 +21,7 @@ Unreleased Version 2.2.0-pre
  * Feature: Make canvas rendering and preview painting asynchronous. This should make the UI much more responsive when e.g. changing layer visibility or transforming a large selection.
  * Fix: Properly handle canvas resizes while transforming a selection, it now no longer causes the source of the transform to get offset.
  * Fix: Show the current color properly on program startup.
+ * Feature: Make the color wheel innards go from least to most saturated, putting it in line with how most other software presents it. This can be toggled in the preferences.
 
 2023-07-31 Version 2.2.0-beta.6
  * Fix: Don't forget account password when entering a wrong session password.

src/desktop/dialogs/settingsdialog/tools.cpp

@@ -116,6 +116,14 @@ void Tools::initColorWheel(desktop::settings::Settings &settings, utils::SanerFo
 
 	form->addSpacer();
 
+	auto *mirror = form->addRadioGroup(tr("Direction:"), false, {
+		{ tr("Ascending"), true },
+		{ tr("Descending"), false }
+	});
+	settings.bindColorWheelMirror(mirror);
+
+	form->addSpacer();
+
 	auto *space = form->addRadioGroup(tr("Color space:"), false, {
 		{ tr("HSV (Hue–Saturation–Value)"),
 			color_widgets::ColorWheel::ColorSpaceEnum::ColorHSV },
@@ -130,6 +138,7 @@ void Tools::initColorWheel(desktop::settings::Settings &settings, utils::SanerFo
 	preview->setMinimumWidth(150);
 	settings.bindColorWheelShape(preview, &color_widgets::ColorWheel::setSelectorShape);
 	settings.bindColorWheelAngle(preview, &color_widgets::ColorWheel::setRotatingSelector);
+	settings.bindColorWheelMirror(preview, &color_widgets::ColorWheel::setMirroredSelector);
 	settings.bindColorWheelSpace(preview, &color_widgets::ColorWheel::setColorSpace);
 	form->addAside(preview, startRow);
 }

src/desktop/docks/colorspinner.cpp

@@ -46,6 +46,7 @@ ColorSpinnerDock::ColorSpinnerDock(const QString& title, QWidget *parent)
 	settings.bindColorWheelShape(d->colorwheel, &color_widgets::ColorWheel::setSelectorShape, &color_widgets::ColorWheel::selectorShapeChanged);
 	settings.bindColorWheelAngleAs<bool>(d->colorwheel, &color_widgets::ColorWheel::setRotatingSelector, &color_widgets::ColorWheel::rotatingSelectorChanged);
 	settings.bindColorWheelSpace(d->colorwheel, &color_widgets::ColorWheel::setColorSpace, &color_widgets::ColorWheel::colorSpaceChanged);
+	settings.bindColorWheelMirror(d->colorwheel, &color_widgets::ColorWheel::setMirroredSelector, &color_widgets::ColorWheel::mirroredSelectorChanged);
 }
 
 ColorSpinnerDock::~ColorSpinnerDock()

src/desktop/settings_table.h

@@ -21,6 +21,7 @@ SETTING(brushOutlineWidth         , BrushOutlineWidth         , "settings/brusho
 SETTING(canvasScrollBars          , CanvasScrollBars          , "settings/canvasscrollbars"             , true)
 SETTING(canvasShortcuts           , CanvasShortcuts           , "settings/canvasshortcuts2"             , QVariantMap())
 SETTING(colorWheelAngle           , ColorWheelAngle           , "settings/colorwheel/rotate"            , color_widgets::ColorWheel::AngleEnum::AngleRotating)
+SETTING(colorWheelMirror          , ColorWheelMirror          , "settings/colorwheel/mirror"            , true)
 SETTING(colorWheelShape           , ColorWheelShape           , "settings/colorwheel/shape"             , color_widgets::ColorWheel::ShapeEnum::ShapeTriangle)
 SETTING(colorWheelSpace           , ColorWheelSpace           , "settings/colorwheel/space"             , color_widgets::ColorWheel::ColorSpaceEnum::ColorHSV)
 SETTING(compactChat               , CompactChat               , "history/compactchat"                   , false)