implemented SDL3 as an option for window manager

TSE_OpenGlImpl/src/shader/ditheringShader.hpp

@@ -0,0 +1,25 @@
+#pragma once
+
+#include "Shader.hpp"
+
+namespace TSE::OpenGL
+{
+    class DitheringShader : public Shader
+    {
+    private:
+        static DitheringShader* instance;
+
+    public:
+        static DitheringShader* Instance();
+        static void Destroy();
+        static void Init(float width, float height);
+        DitheringShader(std::vector<std::unique_ptr<ShaderPart>>&& parts);
+
+    protected:
+        void OnEnable() const override;
+        void OnDisable() const override;
+        void OnFlush() override;
+        void OnDrawCall(int indexCount) override;
+        void OnSubmit(const Transformable& t, float*& target, TransformationStack& stack, void (*restartDrawcall)(IRenderer&), IRenderer& rnd) override;
+    };
+} // namespace TSE::OpenGL