Multi-stop gradients (#219)

CMakeLists.txt

@@ -45,6 +45,7 @@ set(GUIFILES
   gui/timesequencepropertieswindow.cpp
   gui/visualizationwindow.cpp
   gui/components/colorselectwidget.cpp
+  gui/components/colorsequencewidget.cpp
   gui/components/durationinput.cpp
   gui/components/foldercombo.cpp
   gui/components/objectlist.cpp

gui/components/colorsequencewidget.cpp

@@ -0,0 +1,37 @@
+#include "colorsequencewidget.h"
+
+#include "../gradientwindow.h"
+
+#include <glibmm/main.h>
+#include <gtkmm/main.h>
+
+void ColorSequenceWidget::onGradient()
+{
+	if(!_allEqual.get_active() && _widgets.size() > 2)
+	{
+		GradientWindow window(_widgets.size());
+		window.set_modal(true);
+		Gtk::Main::run(window);
+
+		if(window.Result())
+		{
+			std::vector<Color> colors = window.GetColors();
+			_widgets.front()->SetColor(colors.front());
+			_widgets.back()->SetColor(colors.back());
+
+			for(size_t i=1; i<_widgets.size()-1; ++i)
+			{
+				double floatIndex = double(i) * (colors.size() - 1) / (_widgets.size() - 1);
+				Color leftColor = colors[floor(floatIndex)];
+				Color rightColor = colors[floor(floatIndex)+1];
+				double balance = floatIndex - floor(floatIndex);
+				unsigned
+					red = (rightColor.Red() * balance + leftColor.Red() * (1.0 - balance)),
+					green = (rightColor.Green() * balance + leftColor.Green() * (1.0 - balance)),
+					blue = (rightColor.Blue() * balance + leftColor.Blue() * (1.0 - balance));
+				_widgets[i]->SetColor(Color(red, green, blue));
+			}
+		}
+	}
+}
+

gui/components/colorsequencewidget.h

@@ -16,7 +16,7 @@
 class ColorSequenceWidget : public Gtk::VBox
 {
 public:
-	ColorSequenceWidget(Gtk::Window* parent) :
+	ColorSequenceWidget(Gtk::Window* parent, bool showGradientButton = true) :
 		_frame("Colors"),
 		_allEqual("Use one color for all"),
 		_plusButton("+"),
@@ -33,9 +33,12 @@ class ColorSequenceWidget : public Gtk::VBox
 		_minButton.signal_clicked().connect(sigc::mem_fun(*this, &ColorSequenceWidget::onDecreaseColors));
 		_buttonBox.pack_start(_minButton);
 
-		_gradientButton.set_sensitive(false);
-		_gradientButton.signal_clicked().connect(sigc::mem_fun(*this, &ColorSequenceWidget::onGradient));
-		_buttonBox.pack_start(_gradientButton);
+		if(showGradientButton)
+		{
+			_gradientButton.set_sensitive(false);
+			_gradientButton.signal_clicked().connect(sigc::mem_fun(*this, &ColorSequenceWidget::onGradient));
+			_buttonBox.pack_start(_gradientButton);
+		}
 
 		_plusButton.signal_clicked().connect(sigc::mem_fun(*this, &ColorSequenceWidget::onIncreaseColors));
 		_buttonBox.pack_start(_plusButton);
@@ -153,25 +156,9 @@ class ColorSequenceWidget : public Gtk::VBox
 			queue_resize();
 		}
 	}
-	void onGradient()
-	{
-		if(!_allEqual.get_active() && _widgets.size() > 2)
-		{
-			Color frontColor = _widgets.front()->GetColor();
-			Color backColor = _widgets.back()->GetColor();
-			for(size_t i=1; i+1<_widgets.size(); ++i)
-			{
-				unsigned
-					red = (backColor.Red() * i +
-						frontColor.Red() * (_widgets.size() - 1 - i)) / (_widgets.size() - 1),
-					green = (backColor.Green() * i +
-						frontColor.Green() * (_widgets.size() - 1 - i)) / (_widgets.size() - 1),
-					blue = (backColor.Blue() * i +
-						frontColor.Blue() * (_widgets.size() - 1 - i)) / (_widgets.size() - 1);
-				_widgets[i]->SetColor(Color(red, green, blue));
-			}
-		}
-	}
+
+	void onGradient();
+
 	void onFirstColorChange()
 	{
 		if(_allEqual.get_active())

gui/gradientwindow.h

@@ -0,0 +1,43 @@
+#include "components/colorsequencewidget.h"
+
+#include <gtkmm/window.h>
+
+class GradientWindow : public Gtk::Window
+{
+public:
+	GradientWindow(size_t maxCount) :
+		_colorSequence(this, false),
+		_cancelButton("Cancel"),
+		_okayButton("Okay"),
+		_result(false)
+	{
+		set_size_request(250, 300);
+		_colorSequence.SetMinCount(2);
+		_colorSequence.SetMaxCount(maxCount);
+		_box.pack_start(_colorSequence);
+
+		_cancelButton.signal_clicked().connect([&] { hide(); });
+		_buttonBox.pack_start(_cancelButton);
+		_okayButton.signal_clicked().connect([&] { _result = true; hide(); });
+		_buttonBox.pack_start(_okayButton);
+
+		_box.pack_start(_buttonBox);
+
+		add(_box);
+		show_all_children();
+	}
+
+	bool Result() const { return _result; }
+
+	std::vector<Color> GetColors() const
+	{
+		return _colorSequence.GetColors();
+	}
+
+private:
+	Gtk::VBox _box;
+	ColorSequenceWidget _colorSequence;
+	Gtk::ButtonBox _buttonBox;
+	Gtk::Button _cancelButton, _okayButton;
+	bool _result;
+};