Implement FlagMapper for oscimgui

ComputationalBiomechanicsLab · Sep 12, 2024 · e95a418 · e95a418
1 parent 8f5c2ed
commit e95a418
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Showing 8 changed files with 91 additions and 49 deletions.
diff --git a/src/OpenSimCreator/UI/Shared/ObjectPropertiesEditor.cpp b/src/OpenSimCreator/UI/Shared/ObjectPropertiesEditor.cpp
@@ -1578,7 +1578,7 @@ namespace
 
         // create a type-erased entry from a known, concrete, editor
         template<std::derived_from<IPropertyEditor> ConcretePropertyEditor>
-        constexpr static PropertyEditorRegistryEntry make_entry()
+        static constexpr PropertyEditorRegistryEntry make_entry()
         {
             const auto testerFn = ConcretePropertyEditor::IsCompatibleWith;
             const auto typeErasedCtorFn = [](PropertyEditorArgs args) -> std::unique_ptr<IPropertyEditor>

diff --git a/src/oscar/Platform/Log.h b/src/oscar/Platform/Log.h
@@ -69,7 +69,7 @@ namespace osc
 
     namespace detail
     {
-        constexpr static size_t c_max_log_traceback_messages = 512;
+        static constexpr size_t c_max_log_traceback_messages = 512;
     }
 
     [[nodiscard]] LogLevel global_get_traceback_level();

diff --git a/src/oscar/UI/oscimgui.cpp b/src/oscar/UI/oscimgui.cpp
@@ -16,7 +16,9 @@
 #include <oscar/Maths/Quat.h>
 #include <oscar/Maths/Transform.h>
 #include <oscar/Maths/VecFunctions.h>
+#include <oscar/Shims/Cpp23/utility.h>
 #include <oscar/UI/ui_graphics_backend.h>
+#include <oscar/Utils/Flags.h>
 #include <oscar/Utils/EnumHelpers.h>
 #include <oscar/Utils/Conversion.h>
 #include <oscar/Utils/ScopeGuard.h>
@@ -28,11 +30,14 @@
 #include <ImGuizmo.h>
 
 #include <algorithm>
+#include <array>
 #include <cstddef>
 #include <concepts>
 #include <functional>
+#include <initializer_list>
 #include <ranges>
 #include <string_view>
+#include <utility>
 
 using namespace osc;
 using namespace osc::literals;
@@ -83,6 +88,39 @@ namespace
         const Color saturated = saturate(brightened);
         return ui::to_ImU32(saturated);
     }
+
+    // maps between ui:: flag types and imgui flag types
+    template<FlagsEnum SourceFlagType, typename DestinationImGuiFlagsType>
+    requires std::is_enum_v<DestinationImGuiFlagsType> or std::is_integral_v<DestinationImGuiFlagsType>
+    class FlagMapper {
+    public:
+        constexpr FlagMapper(std::initializer_list<std::pair<SourceFlagType, DestinationImGuiFlagsType>> mappings)
+        {
+            if (mappings.size() != num_flags<SourceFlagType>()) {
+                throw std::runtime_error{"invalid number of flags passed to a FlagMapper"};
+            }
+
+            for (const auto& [source_flag, destination_flag] : mappings) {
+                const auto source_index = std::countr_zero(std::bit_floor(cpp23::to_underlying(source_flag)));
+                lut_[source_index] = destination_flag;
+            }
+        }
+
+        constexpr DestinationImGuiFlagsType operator()(Flags<SourceFlagType> flags) const
+        {
+            static_assert(std::is_unsigned_v<std::underlying_type_t<SourceFlagType>>);
+
+            DestinationImGuiFlagsType rv{};
+            for (auto v = to_underlying(flags); v;) {
+                const size_t index = std::countr_zero(v);
+                rv |= lut_[index];
+                v ^= 1<<index;
+            }
+            return rv;
+        }
+    private:
+        std::array<DestinationImGuiFlagsType, num_flags<SourceFlagType>()> lut_{};
+    };
 }
 
 template<>
@@ -114,46 +152,26 @@ struct osc::Converter<ui::GizmoMode, ImGuizmo::MODE> final {
 
 template<>
 struct osc::Converter<ui::TreeNodeFlags, ImGuiTreeNodeFlags> final {
-    ImGuiTreeNodeFlags operator()(ui::TreeNodeFlags flags) const
-    {
-        static_assert(num_flags<ui::TreeNodeFlag>() == 4);
-
-        ImGuiTreeNodeFlags rv = 0;
-        if (flags & ui::TreeNodeFlag::DefaultOpen) {
-            rv |= ImGuiTreeNodeFlags_DefaultOpen;
-        }
-        if (flags & ui::TreeNodeFlag::OpenOnArrow) {
-            rv |= ImGuiTreeNodeFlags_OpenOnArrow;
-        }
-        if (flags & ui::TreeNodeFlag::Leaf) {
-            rv |= ImGuiTreeNodeFlags_Leaf;
-        }
-        if (flags & ui::TreeNodeFlag::Bullet) {
-            rv |= ImGuiTreeNodeFlags_Bullet;
-        }
-        return rv;
-    }
+    ImGuiTreeNodeFlags operator()(ui::TreeNodeFlags flags) const { return c_mappings_(flags); }
+private:
+    static constexpr FlagMapper<ui::TreeNodeFlag, ImGuiTreeNodeFlags> c_mappings_ = {
+        {ui::TreeNodeFlag::DefaultOpen, ImGuiTreeNodeFlags_DefaultOpen},
+        {ui::TreeNodeFlag::OpenOnArrow, ImGuiTreeNodeFlags_OpenOnArrow},
+        {ui::TreeNodeFlag::Leaf,        ImGuiTreeNodeFlags_Leaf},
+        {ui::TreeNodeFlag::Bullet,      ImGuiTreeNodeFlags_Bullet},
+    };
 };
 
 template<>
 struct osc::Converter<ui::TabItemFlags, ImGuiTabItemFlags> final {
-    ImGuiTabItemFlags operator()(ui::TabItemFlags flags) const
-    {
-        ImGuiTabItemFlags rv = 0;
-        if (flags & ui::TabItemFlag::NoReorder) {
-            rv |= ImGuiTabItemFlags_NoReorder;
-        }
-        if (flags & ui::TabItemFlag::NoCloseButton) {
-            rv |= ImGuiTabItemFlags_NoCloseButton;
-        }
-        if (flags & ui::TabItemFlag::UnsavedDocument) {
-            rv |= ImGuiTabItemFlags_UnsavedDocument;
-        }
-        if (flags & ui::TabItemFlag::SetSelected) {
-            rv |= ImGuiTabItemFlags_SetSelected;
-        }
-        return rv;
-    }
+    ImGuiTabItemFlags operator()(ui::TabItemFlags flags) const { return c_mappings_(flags); }
+private:
+    static constexpr FlagMapper<ui::TabItemFlag, ImGuiTabItemFlags> c_mappings_ = {
+        {ui::TabItemFlag::NoReorder,       ImGuiTabItemFlags_NoReorder},
+        {ui::TabItemFlag::NoCloseButton,   ImGuiTabItemFlags_NoCloseButton},
+        {ui::TabItemFlag::UnsavedDocument, ImGuiTabItemFlags_UnsavedDocument},
+        {ui::TabItemFlag::SetSelected,     ImGuiTabItemFlags_SetSelected},
+    };
 };
 
 template<>

diff --git a/src/oscar/UI/oscimgui.h b/src/oscar/UI/oscimgui.h
@@ -104,7 +104,7 @@ namespace osc::ui
 
     bool draw_text_link(CStringView);
 
-    enum class TreeNodeFlag {
+    enum class TreeNodeFlag : unsigned {
         None        = 0,
         DefaultOpen = 1<<0,
         OpenOnArrow = 1<<1,  // only open when clicking on the arrow part
@@ -143,12 +143,13 @@ namespace osc::ui
     bool begin_tab_bar(CStringView str_id);
     void end_tab_bar();
 
-    enum class TabItemFlag {
+    enum class TabItemFlag : unsigned {
         None            = 0,
         NoReorder       = 1<<0,  // disable reordering this tab or having another tab cross over this tab
         NoCloseButton   = 1<<1,  // track whether `p_open` was set or not (we'll need this info on the next frame to recompute ContentWidth during layout)
         UnsavedDocument = 1<<2,  // display a dot next to the title + (internally) set `ImGuiTabItemFlags_NoAssumedClosure`
         SetSelected     = 1<<3,  // trigger flag to programmatically make the tab selected when calling `begin_tab_item`
+        NUM_FLAGS       =    4,
     };
     using TabItemFlags = Flags<TabItemFlag>;
 
@@ -186,7 +187,7 @@ namespace osc::ui
     bool is_mouse_down(MouseButton);
     bool is_mouse_dragging(MouseButton, float lock_threshold = -1.0f);
 
-    enum class SliderFlag {
+    enum class SliderFlag : unsigned {
         None        = 0,
         Logarithmic = 1<<0,
         AlwaysClamp = 1<<1,
@@ -200,7 +201,7 @@ namespace osc::ui
         NUM_OPTIONS
     };
 
-    enum class TextInputFlag {
+    enum class TextInputFlag : unsigned {
         None             = 0,
         ReadOnly         = 1<<0,
         EnterReturnsTrue = 1<<1,
@@ -227,7 +228,7 @@ namespace osc::ui
     bool draw_collapsing_header(CStringView label, TreeNodeFlags = {});
     void draw_dummy(const Vec2& size);
 
-    enum class ComboFlag {
+    enum class ComboFlag : unsigned {
         None = 0,
         NoArrowButton = 1<<0,
         NUM_FLAGS = 1,
@@ -243,7 +244,7 @@ namespace osc::ui
     Vec2 get_main_viewport_center();
     void enable_dockspace_over_main_viewport();
 
-    enum class WindowFlag {
+    enum class WindowFlag : unsigned {
         None                    = 0,
 
         NoMove                  = 1<<0,
@@ -270,7 +271,7 @@ namespace osc::ui
     bool begin_panel(CStringView name, bool* p_open = nullptr, WindowFlags = {});
     void end_panel();
 
-    enum class ChildPanelFlag {
+    enum class ChildPanelFlag : unsigned {
         None   = 0,
         Border = 1<<0,
         NUM_FLAGS = 1,
@@ -326,7 +327,7 @@ namespace osc::ui
 
     void set_next_panel_bg_alpha(float alpha);
 
-    enum class HoveredFlag {
+    enum class HoveredFlag : unsigned {
         None                         = 0,
         AllowWhenDisabled            = 1<<0,
         AllowWhenBlockedByPopup      = 1<<1,
@@ -358,7 +359,7 @@ namespace osc::ui
 
     ID get_id(std::string_view);
 
-    enum class ItemFlag {
+    enum class ItemFlag : unsigned {
         None      = 0,
         Disabled  = 1<<0,
         Inputable = 1<<1,
@@ -782,7 +783,7 @@ namespace osc::ui
     );
 
     // an operation that a ui `Gizmo` shall perform
-    enum class GizmoOperation {
+    enum class GizmoOperation : unsigned {
         None         = 0,
         Translate    = 1<<0,
         Rotate       = 1<<1,

diff --git a/src/oscar/Utils/EnumHelpers.h b/src/oscar/Utils/EnumHelpers.h
@@ -134,6 +134,7 @@ namespace osc
     template<typename TEnum>
     concept FlagsEnum = requires(TEnum v) {
         requires std::is_enum_v<TEnum>;
+        requires std::is_unsigned_v<std::underlying_type_t<TEnum>>;
         TEnum::NUM_FLAGS;
     };
 

diff --git a/src/oscar/Utils/Flags.h b/src/oscar/Utils/Flags.h
@@ -75,9 +75,21 @@ namespace osc
             return Flags{value_ & ~static_cast<underlying_type>(flag)};
         }
 
+        constexpr underlying_type underlying_value() const
+        {
+            return value_;
+        }
+
     private:
         explicit constexpr Flags(underlying_type value) : value_{value} {}
 
         underlying_type value_{};
     };
+
+    template<class TEnum>
+    requires std::is_enum_v<TEnum>
+    constexpr auto to_underlying(const Flags<TEnum>& e) noexcept
+    {
+        return e.underlying_value();
+    }
 }
diff --git a/tests/testoscar/Utils/TestEnumHelpers.cpp b/tests/testoscar/Utils/TestEnumHelpers.cpp
@@ -19,6 +19,6 @@ TEST(num_options, ReturnsValueOfNUMOPTIONSWhenCustomized)
 
 TEST(num_flags, ReturnsValueOfNUMFLAGSEnumMember)
 {
-    enum class SomeFlagsEnum { First = 1<<0, Second = 1<<1, Third = 1<<2, NUM_FLAGS = 3};
+    enum class SomeFlagsEnum : unsigned { First = 1<<0, Second = 1<<1, Third = 1<<2, NUM_FLAGS = 3};
     static_assert(num_flags<SomeFlagsEnum>() == 3);
 }
diff --git a/tests/testoscar/Utils/TestFlags.cpp b/tests/testoscar/Utils/TestFlags.cpp
@@ -3,6 +3,7 @@
 #include <gtest/gtest.h>
 
 #include <array>
+#include <cstdint>
 
 using namespace osc;
 
@@ -222,3 +223,12 @@ TEST(Flags, without_doesnt_set_already_unset_flag)
     const Flags<ExampleDenseFlag> flags_after = flags.without(ExampleDenseFlag::Flag2);
     ASSERT_EQ(flags, flags_after);
 }
+
+TEST(Flags, has_a_to_underlying_specialization)
+{
+    enum class Some16BitEnum : uint16_t {};
+    static_assert(std::is_same_v<decltype(to_underlying(Flags<Some16BitEnum>{})), uint16_t>);
+
+    enum class SomeSigned32BitEnum : int32_t {};
+    static_assert(std::is_same_v<decltype(to_underlying(Flags<SomeSigned32BitEnum>{})), int32_t>);
+}