Start implementing the SVG animation library (and tool)

Libraries/Kanimaji/Source/SVG.cpp

@@ -0,0 +1,117 @@
+#include "SVG.hpp"
+
+#include <format>
+
+namespace Kanimaji::SVG
+{
+    struct Vec2
+    {
+        double x;
+        double y;
+
+        friend Vec2 operator+(const Vec2& u, const Vec2& v)
+        {
+            return Vec2 {
+                .x = u.x + v.x,
+                .y = u.y + v.y,
+            };
+        }
+    };
+
+    class Path::Element
+    {
+    public:
+        virtual ~Element() = default;
+
+        virtual double Length(Vec2 origin) const = 0;
+        virtual Vec2 Endpoint(Vec2 origin) const = 0;
+    };
+
+    namespace
+    {
+        class ParseError : public Error
+        {
+        public:
+            ParseError(std::size_t current, std::string_view message)
+                : Error(std::format("[At: {}] {}", current, message))
+            {}
+        };
+
+        class Move : public Path::Element
+        {
+        public:
+            Move(bool relative, Vec2 move)
+                : mRelative(relative), mMove(move)
+            {}
+
+            double Length(Vec2 origin) const override
+            {
+                return 0;
+            }
+
+            Vec2 Endpoint(Vec2 origin) const override
+            {
+                return mRelative ? origin + mMove : mMove;
+            }
+        private:
+            bool mRelative; // 7B padding, oof
+            Vec2 mMove;
+        };
+
+        class CubicBezier : public Path::Element
+        {
+        public:
+            CubicBezier(bool relative, Vec2 control1, Vec2 control2, Vec2 end)
+                : mRelative(relative), mControl1(control1), mControl2(control2), mEnd(end)
+            {}
+
+            double Length(Vec2 origin) const override
+            {
+                throw Error("not implemented");
+            }
+
+            Vec2 Endpoint(Vec2 origin) const override
+            {
+                return mEnd;
+            }
+        private:
+            bool mRelative; // 7B padding, oof
+            Vec2 mControl1;
+            Vec2 mControl2;
+            Vec2 mEnd;
+        };
+
+        using ElementPtr = std::unique_ptr<Path::Element>;
+        void Parse(std::string_view definition, std::vector<ElementPtr>& elements)
+        {
+            std::size_t current = 0;
+
+            while (current < definition.size()) {
+                switch (definition[current]) {
+                case 'M': [[fallthrough]];
+                case 'm':
+                    // ParseMove
+                    break;
+                case 'C': [[fallthrough]];
+                case 'c':
+                    // ParseCubicBezier
+                    break;
+                default:
+                    throw ParseError(current, "Unrecognized character");
+                }
+            }
+        }
+    }
+
+    Path::Path(std::string_view definition)
+    {
+        Parse(definition, mSegments);
+    }
+
+    Path::~Path() = default;
+
+    double Path::Length() const
+    {
+        return 0;
+    }
+}