LibGUI+FileManager: Add a GIcon class to support multi-size icons.

A GIcon can contain any number of bitmaps internally, and will give you
the best fitting icon when you call bitmap_for_size().

7 files changed, 140 insertions, 2 deletions

diff --git a/LibGUI/GIcon.cpp b/LibGUI/GIcon.cpp
new file mode 100644
index 0000000000..16224f1a97
--- /dev/null
+++ b/LibGUI/GIcon.cpp
@@ -0,0 +1,63 @@
+#include <LibGUI/GIcon.h>
+
+GIcon::GIcon()
+    : m_impl(GIconImpl::create())
+{
+}
+
+GIcon::GIcon(const GIconImpl& impl)
+    : m_impl(const_cast<GIconImpl&>(impl))
+{
+}
+
+GIcon::GIcon(const GIcon& other)
+    : m_impl(other.m_impl.copy_ref())
+{
+}
+
+GIcon::GIcon(RetainPtr<GraphicsBitmap>&& bitmap)
+    : GIcon()
+{
+    if (bitmap) {
+        ASSERT(bitmap->width() == bitmap->height());
+        int size = bitmap->width();
+        set_bitmap_for_size(size, move(bitmap));
+    }
+}
+
+GIcon::GIcon(RetainPtr<GraphicsBitmap>&& bitmap1, RetainPtr<GraphicsBitmap>&& bitmap2)
+    : GIcon(move(bitmap1))
+{
+    if (bitmap2) {
+        ASSERT(bitmap2->width() == bitmap2->height());
+        int size = bitmap2->width();
+        set_bitmap_for_size(size, move(bitmap2));
+    }
+}
+
+const GraphicsBitmap* GIconImpl::bitmap_for_size(int size) const
+{
+    auto it = m_bitmaps.find(size);
+    if (it != m_bitmaps.end())
+        return it->value.ptr();
+
+    int best_diff_so_far = INT32_MAX;
+    const GraphicsBitmap* best_fit = nullptr;
+    for (auto& it : m_bitmaps) {
+        int abs_diff = abs(it.key - size);
+        if (abs_diff < best_diff_so_far) {
+            best_diff_so_far = abs_diff;
+            best_fit = it.value.ptr();
+        }
+    }
+    return best_fit;
+}
+
+void GIconImpl::set_bitmap_for_size(int size, RetainPtr<GraphicsBitmap>&& bitmap)
+{
+    if (!bitmap) {
+        m_bitmaps.remove(size);
+        return;
+    }
+    m_bitmaps.set(size, move(bitmap));
+}
diff --git a/LibGUI/GIcon.h b/LibGUI/GIcon.h
new file mode 100644
index 0000000000..bfb48496ba
--- /dev/null
+++ b/LibGUI/GIcon.h
@@ -0,0 +1,41 @@
+#pragma once
+
+#include <SharedGraphics/GraphicsBitmap.h>
+#include <AK/HashMap.h>
+
+class GIconImpl : public Retainable<GIconImpl> {
+public:
+    static Retained<GIconImpl> create() { return adopt(*new GIconImpl); }
+    ~GIconImpl() { }
+
+    const GraphicsBitmap* bitmap_for_size(int) const;
+    void set_bitmap_for_size(int, RetainPtr<GraphicsBitmap>&&);
+
+private:
+    GIconImpl() { }
+    HashMap<int, RetainPtr<GraphicsBitmap>> m_bitmaps;
+};
+
+class GIcon {
+public:
+    GIcon();
+    explicit GIcon(RetainPtr<GraphicsBitmap>&&);
+    explicit GIcon(RetainPtr<GraphicsBitmap>&&, RetainPtr<GraphicsBitmap>&&);
+    explicit GIcon(const GIconImpl&);
+    GIcon(const GIcon&);
+    ~GIcon() { }
+
+    GIcon& operator=(const GIcon& other)
+    {
+        m_impl = other.m_impl.copy_ref();
+        return *this;
+    }
+
+    const GraphicsBitmap* bitmap_for_size(int size) const { return m_impl->bitmap_for_size(size); }
+    void set_bitmap_for_size(int size, RetainPtr<GraphicsBitmap>&& bitmap) { m_impl->set_bitmap_for_size(size, move(bitmap)); }
+
+    const GIconImpl& impl() const { return *m_impl; }
+
+private:
+    Retained<GIconImpl> m_impl;
+};
diff --git a/LibGUI/GItemView.cpp b/LibGUI/GItemView.cpp
index db0499c121..39c2f2cb04 100644
--- a/LibGUI/GItemView.cpp
+++ b/LibGUI/GItemView.cpp
@@ -110,8 +110,9 @@ void GItemView::paint_event(GPaintEvent& event)
         icon_rect.center_within(item_rect);
         icon_rect.move_by(0, -font.glyph_height() - 6);
 
-        if (icon.is_bitmap()) {
-            painter.draw_scaled_bitmap(icon_rect, icon.as_bitmap(), icon.as_bitmap().rect());
+        if (icon.is_icon()) {
+            if (auto bitmap = icon.as_icon().bitmap_for_size(icon_rect.width()))
+                painter.draw_scaled_bitmap(icon_rect, *bitmap, bitmap->rect());
         }
 
         Rect text_rect { 0, icon_rect.bottom() + 6 + 1, font.width(item_text.to_string()), font.glyph_height() };
diff --git a/LibGUI/GTableView.cpp b/LibGUI/GTableView.cpp
index e753002ab7..81797be626 100644
--- a/LibGUI/GTableView.cpp
+++ b/LibGUI/GTableView.cpp
@@ -141,6 +141,9 @@ void GTableView::paint_event(GPaintEvent& event)
             auto data = model()->data(cell_index);
             if (data.is_bitmap()) {
                 painter.blit(cell_rect.location(), data.as_bitmap(), data.as_bitmap().rect());
+            } else if (data.is_icon()) {
+                if (auto bitmap = data.as_icon().bitmap_for_size(16))
+                    painter.blit(cell_rect.location(), *bitmap, bitmap->rect());
             } else {
                 Color text_color;
                 if (is_selected_row)
diff --git a/LibGUI/GVariant.cpp b/LibGUI/GVariant.cpp
index 1e8b7d187a..6f9d62a620 100644
--- a/LibGUI/GVariant.cpp
+++ b/LibGUI/GVariant.cpp
@@ -15,6 +15,10 @@ GVariant::~GVariant()
         if (m_value.as_bitmap)
             m_value.as_bitmap->release();
         break;
+    case Type::Icon:
+        if (m_value.as_icon)
+            m_value.as_icon->release();
+        break;
     default:
         break;
     }
@@ -52,6 +56,13 @@ GVariant::GVariant(const GraphicsBitmap& value)
     AK::retain_if_not_null(m_value.as_bitmap);
 }
 
+GVariant::GVariant(const GIcon& value)
+    : m_type(Type::Icon)
+{
+    m_value.as_icon = &const_cast<GIconImpl&>(value.impl());
+    AK::retain_if_not_null(m_value.as_icon);
+}
+
 GVariant::GVariant(Color color)
     : m_type(Type::Color)
 {
@@ -73,6 +84,8 @@ bool GVariant::operator==(const GVariant& other) const
         return as_string() == other.as_string();
     case Type::Bitmap:
         return m_value.as_bitmap == other.m_value.as_bitmap;
+    case Type::Icon:
+        return m_value.as_icon == other.m_value.as_icon;
     case Type::Color:
         return m_value.as_color == other.m_value.as_color;
     case Type::Invalid:
@@ -97,6 +110,9 @@ bool GVariant::operator<(const GVariant& other) const
     case Type::Bitmap:
         // FIXME: Maybe compare bitmaps somehow differently?
         return m_value.as_bitmap < other.m_value.as_bitmap;
+    case Type::Icon:
+        // FIXME: Maybe compare icons somehow differently?
+        return m_value.as_icon < other.m_value.as_icon;
     case Type::Color:
         return m_value.as_color < other.m_value.as_color;
     case Type::Invalid:
@@ -118,6 +134,8 @@ String GVariant::to_string() const
         return as_string();
     case Type::Bitmap:
         return "[GraphicsBitmap]";
+    case Type::Icon:
+        return "[GIcon]";
     case Type::Color:
         return as_color().to_string();
     case Type::Invalid:
diff --git a/LibGUI/GVariant.h b/LibGUI/GVariant.h
index 1346188015..3631c6e581 100644
--- a/LibGUI/GVariant.h
+++ b/LibGUI/GVariant.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <AK/AKString.h>
+#include <LibGUI/GIcon.h>
 #include <SharedGraphics/GraphicsBitmap.h>
 
 class GVariant {
@@ -11,6 +12,7 @@ public:
     GVariant(int);
     GVariant(const String&);
     GVariant(const GraphicsBitmap&);
+    GVariant(const GIcon&);
     GVariant(Color);
     ~GVariant();
 
@@ -22,6 +24,7 @@ public:
         String,
         Bitmap,
         Color,
+        Icon,
     };
 
     bool is_valid() const { return m_type != Type::Invalid; }
@@ -31,6 +34,7 @@ public:
     bool is_string() const { return m_type == Type::String; }
     bool is_bitmap() const { return m_type == Type::Bitmap; }
     bool is_color() const { return m_type == Type::Color; }
+    bool is_icon() const { return m_type == Type::Icon; }
     Type type() const { return m_type; }
 
     bool as_bool() const
@@ -63,6 +67,12 @@ public:
         return *m_value.as_bitmap;
     }
 
+    GIcon as_icon() const
+    {
+        ASSERT(type() == Type::Icon);
+        return GIcon(*m_value.as_icon);
+    }
+
     Color as_color() const
     {
         ASSERT(type() == Type::Color);
@@ -85,6 +95,7 @@ private:
     union {
         StringImpl* as_string;
         GraphicsBitmap* as_bitmap;
+        GIconImpl* as_icon;
         bool as_bool;
         int as_int;
         float as_float;
diff --git a/LibGUI/Makefile b/LibGUI/Makefile
index 1cd0beaf53..6d67ef550f 100644
--- a/LibGUI/Makefile
+++ b/LibGUI/Makefile
@@ -50,6 +50,7 @@ LIBGUI_OBJS = \
     GProgressBar.o \
     GAbstractView.o \
     GItemView.o \
+    GIcon.o \
     GWindow.o
 
 OBJS = $(SHAREDGRAPHICS_OBJS) $(LIBGUI_OBJS)