refactor export equirectangular

src/texture.h

@@ -23,9 +23,30 @@ public:
     bool ready() const { return m_tex != 0; }
     void create_mipmaps();
     glm::vec2 size() const;
+    Image get_image() const noexcept;
     ~Texture2D();
 };
 
+struct TextureCube
+{
+    TextureCube() noexcept = default;
+    TextureCube(const TextureCube&) = delete;
+    void operator=(const TextureCube&) = delete;
+    TextureCube(TextureCube&& other) noexcept;
+    void operator=(TextureCube&& other) noexcept;
+    ~TextureCube() noexcept;
+    
+    static std::array<int, 6> m_faces_map;
+
+    GLuint m_cubetex_id;
+    std::array<GLuint, 6> m_faces{ 0 };
+    int m_resolution = 0;
+
+    bool create(int resolution) noexcept;
+    void destroy() noexcept;
+    void bind() const noexcept;
+};
+
 class Sampler
 {
     GLuint id = 0;