Add XCUI ImGui transition backend MVP

engine/include/XCEngine/UI/DrawData.h

@@ -0,0 +1,204 @@
+#pragma once
+
+#include <XCEngine/UI/Types.h>
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace XCEngine {
+namespace UI {
+
+struct UIColor {
+    float r = 1.0f;
+    float g = 1.0f;
+    float b = 1.0f;
+    float a = 1.0f;
+
+    constexpr UIColor() = default;
+    constexpr UIColor(float red, float green, float blue, float alpha = 1.0f)
+        : r(red)
+        , g(green)
+        , b(blue)
+        , a(alpha) {
+    }
+};
+
+enum class UIDrawCommandType : std::uint8_t {
+    FilledRect = 0,
+    RectOutline,
+    Text,
+    Image,
+    PushClipRect,
+    PopClipRect
+};
+
+struct UIDrawCommand {
+    UIDrawCommandType type = UIDrawCommandType::FilledRect;
+    UIRect rect = {};
+    UIPoint position = {};
+    UIColor color = {};
+    float thickness = 1.0f;
+    float rounding = 0.0f;
+    float fontSize = 0.0f;
+    bool intersectWithCurrentClip = true;
+    UITextureHandle texture = {};
+    std::string text;
+};
+
+class UIDrawList {
+public:
+    UIDrawList() = default;
+    explicit UIDrawList(std::string debugName)
+        : m_debugName(std::move(debugName)) {
+    }
+
+    const std::string& GetDebugName() const {
+        return m_debugName;
+    }
+
+    void SetDebugName(std::string debugName) {
+        m_debugName = std::move(debugName);
+    }
+
+    void Clear() {
+        m_commands.clear();
+    }
+
+    bool Empty() const {
+        return m_commands.empty();
+    }
+
+    std::size_t GetCommandCount() const {
+        return m_commands.size();
+    }
+
+    const std::vector<UIDrawCommand>& GetCommands() const {
+        return m_commands;
+    }
+
+    UIDrawCommand& AddFilledRect(
+        const UIRect& rect,
+        const UIColor& color,
+        float rounding = 0.0f) {
+        UIDrawCommand command = {};
+        command.type = UIDrawCommandType::FilledRect;
+        command.rect = rect;
+        command.color = color;
+        command.rounding = rounding;
+        return AddCommand(std::move(command));
+    }
+
+    UIDrawCommand& AddRectOutline(
+        const UIRect& rect,
+        const UIColor& color,
+        float thickness = 1.0f,
+        float rounding = 0.0f) {
+        UIDrawCommand command = {};
+        command.type = UIDrawCommandType::RectOutline;
+        command.rect = rect;
+        command.color = color;
+        command.thickness = thickness;
+        command.rounding = rounding;
+        return AddCommand(std::move(command));
+    }
+
+    UIDrawCommand& AddText(
+        const UIPoint& position,
+        std::string text,
+        const UIColor& color = {},
+        float fontSize = 0.0f) {
+        UIDrawCommand command = {};
+        command.type = UIDrawCommandType::Text;
+        command.position = position;
+        command.color = color;
+        command.fontSize = fontSize;
+        command.text = std::move(text);
+        return AddCommand(std::move(command));
+    }
+
+    UIDrawCommand& AddImage(
+        const UIRect& rect,
+        const UITextureHandle& texture,
+        const UIColor& tintColor = {}) {
+        UIDrawCommand command = {};
+        command.type = UIDrawCommandType::Image;
+        command.rect = rect;
+        command.texture = texture;
+        command.color = tintColor;
+        return AddCommand(std::move(command));
+    }
+
+    UIDrawCommand& PushClipRect(
+        const UIRect& rect,
+        bool intersectWithCurrentClip = true) {
+        UIDrawCommand command = {};
+        command.type = UIDrawCommandType::PushClipRect;
+        command.rect = rect;
+        command.intersectWithCurrentClip = intersectWithCurrentClip;
+        return AddCommand(std::move(command));
+    }
+
+    UIDrawCommand& PopClipRect() {
+        UIDrawCommand command = {};
+        command.type = UIDrawCommandType::PopClipRect;
+        return AddCommand(std::move(command));
+    }
+
+private:
+    UIDrawCommand& AddCommand(UIDrawCommand&& command) {
+        m_commands.push_back(std::move(command));
+        return m_commands.back();
+    }
+
+    std::string m_debugName;
+    std::vector<UIDrawCommand> m_commands;
+};
+
+class UIDrawData {
+public:
+    void Clear() {
+        m_drawLists.clear();
+    }
+
+    bool Empty() const {
+        return m_drawLists.empty();
+    }
+
+    std::size_t GetDrawListCount() const {
+        return m_drawLists.size();
+    }
+
+    std::size_t GetTotalCommandCount() const {
+        std::size_t count = 0;
+        for (const UIDrawList& drawList : m_drawLists) {
+            count += drawList.GetCommandCount();
+        }
+        return count;
+    }
+
+    const std::vector<UIDrawList>& GetDrawLists() const {
+        return m_drawLists;
+    }
+
+    UIDrawList& EmplaceDrawList(std::string debugName = {}) {
+        m_drawLists.emplace_back(std::move(debugName));
+        return m_drawLists.back();
+    }
+
+    void AddDrawList(const UIDrawList& drawList) {
+        m_drawLists.push_back(drawList);
+    }
+
+    void AddDrawList(UIDrawList&& drawList) {
+        m_drawLists.push_back(std::move(drawList));
+    }
+
+private:
+    std::vector<UIDrawList> m_drawLists;
+};
+
+} // namespace UI
+} // namespace XCEngine