Allow to drag mouse outside color wheel to select colors at the circumference

src/app/ui/color_selector.cpp

@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2018-2020  Igara Studio S.A.
+// Copyright (C) 2018-2021  Igara Studio S.A.
 // Copyright (C) 2016-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -226,8 +226,6 @@ ColorSelector::ColorSelector()
   : Widget(kGenericWidget)
   , m_paintFlags(AllAreasFlag)
   , m_lockColor(false)
-  , m_capturedInBottom(false)
-  , m_capturedInAlpha(false)
   , m_timer(100, this)
 {
   initTheme();
@@ -312,6 +310,9 @@ bool ColorSelector::onProcessMessage(ui::Message* msg)
       if (msg->type() == kMouseDownMessage) {
         m_capturedInBottom = bottomBarBounds().contains(pos);
         m_capturedInAlpha = alphaBarBounds().contains(pos);
+        m_capturedInMain = (hasCapture() &&
+                            !m_capturedInMain &&
+                            !m_capturedInBottom);
       }
 
       app::Color color = getColorByPosition(pos);
@@ -329,6 +330,7 @@ bool ColorSelector::onProcessMessage(ui::Message* msg)
       if (hasCapture()) {
         m_capturedInBottom = false;
         m_capturedInAlpha = false;
+        m_capturedInMain = false;
         releaseMouse();
       }
       return true;

src/app/ui/color_selector.h

@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2018-2020  Igara Studio S.A.
+// Copyright (C) 2018-2021  Igara Studio S.A.
 // Copyright (C) 2016-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -82,6 +82,8 @@ namespace app {
     // m_color.getAlpha() if it's really a color.
     int getCurrentAlphaForNewColor() const;
 
+    bool hasCaptureInMainArea() const { return m_capturedInMain; }
+
     app::Color m_color;
 
     // These flags indicate which areas must be redrawed in the
@@ -108,8 +110,9 @@ namespace app {
     // slider. It's used to avoid swapping in both areas (main color
     // area vs bottom slider) when we drag the mouse above this
     // widget.
-    bool m_capturedInBottom;
-    bool m_capturedInAlpha;
+    bool m_capturedInBottom = false;
+    bool m_capturedInAlpha = false;
+    bool m_capturedInMain = false;
 
     ui::Timer m_timer;
 

src/app/ui/color_wheel.cpp

@@ -74,8 +74,37 @@ app::Color ColorWheel::getMainAreaColor(const int _u, const int umax,
 
   int u = _u - umax/2;
   int v = _v - vmax/2;
+
+  // Pick harmonies
+  if (m_color.getAlpha() > 0) {
+    const gfx::Point pos(_u, _v);
+    int n = getHarmonies();
+    int boxsize = std::min(umax/10, vmax/10);
+
+    for (int i=0; i<n; ++i) {
+      app::Color color = getColorInHarmony(i);
+
+      if (gfx::Rect(umax-(n-i)*boxsize,
+                    vmax-boxsize,
+                    boxsize, boxsize).contains(pos)) {
+        m_harmonyPicked = true;
+
+        color = app::Color::fromHsv(convertHueAngle(int(color.getHsvHue()), 1),
+                                    color.getHsvSaturation(),
+                                    color.getHsvValue(),
+                                    m_color.getAlpha());
+        return color;
+      }
+    }
+  }
+
   double d = std::sqrt(u*u + v*v);
 
+  // When we click the main area we can limit the distance to the
+  // wheel radius to pick colors even outside the wheel radius.
+  if (hasCaptureInMainArea() && d > m_wheelRadius)
+    d = m_wheelRadius;
+
   if (m_colorModel == ColorModel::NORMAL_MAP) {
     double a = std::atan2(-v, u);
     int di = int(128.0 * d / m_wheelRadius);
@@ -138,29 +167,6 @@ app::Color ColorWheel::getMainAreaColor(const int _u, const int umax,
       getCurrentAlphaForNewColor());
   }
 
-  // Pick harmonies
-  if (m_color.getAlpha() > 0) {
-    const gfx::Point pos(_u, _v);
-    int n = getHarmonies();
-    int boxsize = std::min(umax/10, vmax/10);
-
-    for (int i=0; i<n; ++i) {
-      app::Color color = getColorInHarmony(i);
-
-      if (gfx::Rect(umax-(n-i)*boxsize,
-                    vmax-boxsize,
-                    boxsize, boxsize).contains(pos)) {
-        m_harmonyPicked = true;
-
-        color = app::Color::fromHsv(convertHueAngle(int(color.getHsvHue()), 1),
-                                    color.getHsvSaturation(),
-                                    color.getHsvValue(),
-                                    m_color.getAlpha());
-        return color;
-      }
-    }
-  }
-
   return app::Color::fromMask();
 }