LibGUI: Support different button styles.

I want to try an MS Office 97 "CoolBar" inspired look for my toolbars.
This is only the painting support, we still need hover events to implement
the actual effect.

LibGUI/GButton.cpp

@@ -26,7 +26,7 @@ void GButton::paint_event(GPaintEvent&)
 {
     Painter painter(*this);
 
-    GStyle::the().paint_button(painter, rect(), m_being_pressed);
+    GStyle::the().paint_button(painter, rect(), m_button_style, m_being_pressed, m_hovered);
 
     if (!caption().is_empty() || m_icon) {
         auto content_rect = rect();

LibGUI/GButton.h

@@ -1,6 +1,7 @@
 #pragma once
 
-#include "GWidget.h"
+#include <LibGUI/GWidget.h>
+#include <LibGUI/GStyle.h>
 #include <AK/AKString.h>
 #include <AK/Function.h>
 #include <SharedGraphics/GraphicsBitmap.h>
@@ -19,6 +20,9 @@ public:
 
     Function<void(GButton&)> on_click;
 
+    void set_button_style(GButtonStyle style) { m_button_style = style; }
+    GButtonStyle button_style() const { return m_button_style; }
+
 private:
     virtual void paint_event(GPaintEvent&) override;
     virtual void mousedown_event(GMouseEvent&) override;
@@ -29,7 +33,9 @@ private:
 
     String m_caption;
     RetainPtr<GraphicsBitmap> m_icon;
+    GButtonStyle m_button_style { GButtonStyle::Normal };
     bool m_being_pressed { false };
     bool m_tracking_cursor { false };
+    bool m_hovered { false };
 };
 

LibGUI/GScrollBar.cpp

@@ -187,14 +187,14 @@ void GScrollBar::paint_event(GPaintEvent&)
 
     painter.fill_rect(rect(), Color(164, 164, 164));
 
-    GStyle::the().paint_button(painter, up_button_rect(), false);
+    GStyle::the().paint_button(painter, up_button_rect(), GButtonStyle::Normal, false);
     painter.draw_bitmap(up_button_rect().location().translated(3, 3), orientation() == Orientation::Vertical ? *s_up_arrow_bitmap : *s_left_arrow_bitmap, has_scrubber() ? Color::Black : Color::MidGray);
 
-    GStyle::the().paint_button(painter, down_button_rect(), false);
+    GStyle::the().paint_button(painter, down_button_rect(), GButtonStyle::Normal, false);
     painter.draw_bitmap(down_button_rect().location().translated(3, 3), orientation() == Orientation::Vertical ? *s_down_arrow_bitmap : *s_right_arrow_bitmap, has_scrubber() ? Color::Black : Color::MidGray);
 
     if (has_scrubber())
-        GStyle::the().paint_button(painter, scrubber_rect(), false);
+        GStyle::the().paint_button(painter, scrubber_rect(), GButtonStyle::Normal, false);
 }
 
 void GScrollBar::mousedown_event(GMouseEvent& event)

LibGUI/GStyle.cpp

@@ -14,12 +14,14 @@ GStyle::GStyle()
 {
 }
 
-void GStyle::paint_button(Painter& painter, const Rect& rect, bool pressed)
+void GStyle::paint_button(Painter& painter, const Rect& rect, GButtonStyle button_style, bool pressed, bool hovered)
 {
     Color button_color = Color::LightGray;
     Color highlight_color = Color::White;
     Color shadow_color = Color(96, 96, 96);
-    painter.draw_rect(rect, Color::Black, true);
+
+    if (button_style == GButtonStyle::Normal)
+        painter.draw_rect(rect, Color::Black, true);
 
     painter.translate(rect.location());
 
@@ -30,22 +32,22 @@ void GStyle::paint_button(Painter& painter, const Rect& rect, bool pressed)
         // Sunken shadow
         painter.draw_line({ 1, 1 }, { rect.width() - 2, 1 }, shadow_color);
         painter.draw_line({ 1, 2 }, {1, rect.height() - 2 }, shadow_color);
-    } else {
+
+        // Bottom highlight
+        painter.draw_line({ rect.width() - 2, 1 }, { rect.width() - 2, rect.height() - 3 }, highlight_color);
+        painter.draw_line({ 1, rect.height() - 2 }, { rect.width() - 2, rect.height() - 2 }, highlight_color);
+    } else if (button_style == GButtonStyle::Normal || (button_style == GButtonStyle::CoolBar && hovered)) {
         // Base
         painter.fill_rect({ 3, 3, rect.width() - 5, rect.height() - 5 }, button_color);
         painter.fill_rect_with_gradient({ 2, 2, rect.width() - 3, rect.height() - 3 }, button_color, Color::White);
 
         // White highlight
         painter.draw_line({ 1, 1 }, { rect.width() - 2, 1 }, highlight_color);
-        //painter.draw_line({ 1, 2 }, { rect.width() - 3, 2 }, highlight_color);
         painter.draw_line({ 1, 2 }, { 1, rect.height() - 2 }, highlight_color);
-        //painter.draw_line({ 2, 3 }, { 2, rect.height() - 3 }, highlight_color);
 
         // Gray shadow
         painter.draw_line({ rect.width() - 2, 1 }, { rect.width() - 2, rect.height() - 3 }, shadow_color);
-        //painter.draw_line({ rect.width() - 3, 2 }, { rect.width() - 3, rect.height() - 4 }, shadow_color);
         painter.draw_line({ 1, rect.height() - 2 }, { rect.width() - 2, rect.height() - 2 }, shadow_color);
-        //painter.draw_line({ 2, rect.height() - 3 }, { rect.width() - 2, rect.height() - 3 }, shadow_color);
     }
 
     painter.translate(-rect.location().x(), -rect.location().y());

LibGUI/GStyle.h

@@ -3,11 +3,13 @@
 class Painter;
 class Rect;
 
+enum class GButtonStyle { Normal, CoolBar };
+
 class GStyle {
 public:
     static GStyle& the();
 
-    void paint_button(Painter& painter, const Rect& rect, bool pressed);
+    void paint_button(Painter& painter, const Rect& rect, GButtonStyle, bool pressed, bool hovered = false);
 
 private:
     GStyle();

LibGUI/GToolBar.cpp

@@ -35,6 +35,7 @@ void GToolBar::add_action(RetainPtr<GAction>&& action)
         raw_action_ptr->activate();
     };
 
+    button->set_button_style(GButtonStyle::CoolBar);
     button->set_size_policy(SizePolicy::Fixed, SizePolicy::Fixed);
     button->set_preferred_size({ 22, 22 });