Add ui::checkbox interface & default implementation

libs/ui/include/psemek/ui/checkbox.hpp

@@ -0,0 +1,45 @@
+#pragma once
+
+#include <psemek/ui/element.hpp>
+
+#include <functional>
+
+namespace psemek::ui
+{
+
+	struct checkbox
+		: element
+	{
+		bool on_event(mouse_move const & e) override;
+		bool on_event(mouse_click const & e) override;
+
+		bool value() const { return value_; }
+		void set_value(bool value) { value_ = value; }
+
+		using on_value_changed_callback = std::function<void(bool)>;
+
+		void on_value_changed(on_value_changed_callback callback)
+		{
+			callback_ = std::move(callback);
+		}
+
+	protected:
+		enum class state_t
+		{
+			normal,
+			mouseover,
+			mousedown,
+		};
+
+		virtual state_t state() const { return state_; }
+
+		virtual void on_state_changed(state_t old);
+
+	private:
+		state_t state_ = state_t::normal;
+		bool value_ = false;
+
+		on_value_changed_callback callback_;
+	};
+
+}

libs/ui/include/psemek/ui/default_element_factory.hpp

@@ -17,6 +17,7 @@ namespace psemek::ui
 		using element_factory::make_button;
 		std::shared_ptr<frame> make_frame() override;
 		std::shared_ptr<window> make_window(std::string caption) override;
+		std::shared_ptr<checkbox> make_checkbox(bool value) override;
 		std::shared_ptr<slider> make_slider() override;
 		std::shared_ptr<spinbox> make_spinbox() override;
 

libs/ui/include/psemek/ui/element_factory.hpp

@@ -9,6 +9,7 @@
 #include <psemek/ui/grid_layout.hpp>
 #include <psemek/ui/image_view.hpp>
 #include <psemek/ui/rich_image_view.hpp>
+#include <psemek/ui/checkbox.hpp>
 #include <psemek/ui/slider.hpp>
 #include <psemek/ui/spinbox.hpp>
 
@@ -29,6 +30,7 @@ namespace psemek::ui
 		virtual std::shared_ptr<grid_layout> make_grid_layout();
 		virtual std::shared_ptr<image_view> make_image_view(std::shared_ptr<gfx::texture_2d> image);
 		virtual std::shared_ptr<rich_image_view> make_rich_image_view(std::shared_ptr<gfx::texture_2d> image);
+		virtual std::shared_ptr<checkbox> make_checkbox(bool value);
 		virtual std::shared_ptr<slider> make_slider();
 		virtual std::shared_ptr<spinbox> make_spinbox();
 

libs/ui/source/checkbox.cpp

@@ -0,0 +1,71 @@
+#include <psemek/ui/checkbox.hpp>
+
+namespace psemek::ui
+{
+
+	bool checkbox::on_event(mouse_move const & e)
+	{
+		bool const over = shape().contains(geom::cast<float>(e.position));
+
+		switch (state_) {
+		case state_t::normal:
+			if (over)
+			{
+				state_ = state_t::mouseover;
+				on_state_changed(state_t::normal);
+			}
+			break;
+		case state_t::mouseover:
+		case state_t::mousedown:
+			if (!over)
+			{
+				auto old = state_;
+				state_ = state_t::normal;
+				on_state_changed(old);
+			}
+			break;
+		}
+
+		return false;
+	}
+
+	bool checkbox::on_event(mouse_click const & e)
+	{
+		if (e.button != mouse_button::left) return false;
+
+		switch (state_) {
+		case state_t::normal:
+			break;
+		case state_t::mouseover:
+			if (e.down)
+			{
+				state_ = state_t::mousedown;
+				value_ = !value_;
+				if (callback_)
+					post([cb = callback_, v = value_]{ cb(v); });
+				on_state_changed(state_t::mouseover);
+				return true;
+			}
+			break;
+		case state_t::mousedown:
+			if (!e.down)
+			{
+				state_ = state_t::mouseover;
+				on_state_changed(state_t::mousedown);
+				return true;
+			}
+			break;
+		}
+
+		return false;
+	}
+
+	void checkbox::on_state_changed(state_t old)
+	{
+		if (state() == state_t::mousedown || old == state_t::mousedown)
+		{
+			post_reshape();
+		}
+	}
+
+}

libs/ui/source/default_element_factory.cpp

@@ -360,6 +360,84 @@ namespace psemek::ui
 			element * children_[3];
 		};
 
+		struct checkbox_impl
+			: checkbox
+		{
+			struct shape const & shape() const override
+			{
+				return shape_;
+			}
+
+			void reshape(geom::box<float, 2> const & bbox) override
+			{
+				shape_.box = geom::expand(geom::box<float, 2>::singleton(bbox.center()), size() / 2.f);
+			}
+
+			void draw(painter & p) const override
+			{
+				auto st = merged_style();
+				if (!st) return;
+
+				geom::box<float, 2> boxes[5];
+
+				boxes[0] = {{shape_.box[0], {shape_.box[1].min, shape_.box[1].min + outer_width()}}};
+				boxes[1] = {{shape_.box[0], {shape_.box[1].max - outer_width(), shape_.box[1].max}}};
+				boxes[2] = {{{shape_.box[0].min, shape_.box[0].min + outer_width()}, {shape_.box[1].min + outer_width(), shape_.box[1].max - outer_width()}}};
+				boxes[3] = {{{shape_.box[0].max - outer_width(), shape_.box[0].max}, {shape_.box[1].min + outer_width(), shape_.box[1].max - outer_width()}}};
+				boxes[4] = geom::shrink(shape_.box, 0.f + outer_width() + outer_margin());
+
+				int const box_count = value() ? 5 : 4;
+
+				if (st->shadow_offset != geom::vector{0, 0})
+				{
+					auto const offset = geom::cast<float>(*st->shadow_offset);
+					for (int b = 0; b < box_count; ++b)
+						p.draw_rect(boxes[b] + offset, *st->shadow_color);
+				}
+
+				auto offset = geom::vector{0.f, 0.f};
+				if (state() == state_t::mousedown)
+					offset = geom::cast<float>(*st->action_offset);
+
+				gfx::color_rgba color = *st->fg_color;
+				if (state() == state_t::mouseover)
+					color = *st->highlight_color;
+				else if (state() == state_t::mousedown)
+					color = *st->action_color;
+
+				for (int b = 0; b < box_count; ++b)
+					p.draw_rect(boxes[b] + offset, color);
+			}
+
+			geom::box<float, 2> size_constraints() const override
+			{
+				auto sc = element::size_constraints();
+
+				sc[0] &= geom::interval<float>{size(), std::numeric_limits<float>::infinity()};
+				sc[1] &= geom::interval<float>{size(), std::numeric_limits<float>::infinity()};
+
+				return sc;
+			}
+
+		private:
+			box_shape shape_;
+
+			int size() const
+			{
+				return *merged_style()->ref_height;
+			}
+
+			int outer_width() const
+			{
+				return *merged_style()->ref_height / 8;
+			}
+
+			int outer_margin() const
+			{
+				return *merged_style()->ref_height / 8;
+			}
+		};
+
 		struct slider_impl
 			: slider
 		{
@@ -627,6 +705,13 @@ namespace psemek::ui
 		return std::make_shared<spinbox_impl>();
 	}
 
+	std::shared_ptr<checkbox> default_element_factory::make_checkbox(bool value)
+	{
+		auto c = std::make_shared<checkbox_impl>();
+		c->set_value(value);
+		return c;
+	}
+
 	std::shared_ptr<slider> default_element_factory::make_slider()
 	{
 		return std::make_shared<slider_impl>();

libs/ui/source/element_factory.cpp

@@ -73,6 +73,11 @@ namespace psemek::ui
 		return i;
 	}
 
+	std::shared_ptr<checkbox> element_factory::make_checkbox(bool)
+	{
+		return nullptr;
+	}
+
 	std::shared_ptr<slider> element_factory::make_slider() { return nullptr; }
 
 	std::shared_ptr<spinbox> element_factory::make_spinbox() { return nullptr; }