public:

enum class axes_category {

two_dimensional,

three_dimensional,

three_dimensional_map,

polar

};

public:

explicit axes_object(class axes_type *parent);

explicit axes_object(axes_handle parent);

public:

virtual double xmax();

virtual double xmin();

virtual double ymax();

virtual double ymin();

virtual double zmax();

virtual double zmin();

virtual axes_category axes_category();

virtual bool requires_colormap();

virtual std::string tag();

virtual void tag(std::string_view);

bool is_3d();

bool is_3d_map();

bool is_2d();

bool is_polar();

public /* for the backend */:

virtual void run_draw_commands();

public /* for gnuplot backend only */:

virtual std::string set_variables_string();

// Plot command for this object

virtual std::string plot_string() = 0;

// Create a legend string for this object

// https://stackoverflow.com/questions/60617211/how-to-put-a-rectangle-in-the-key-with-same-hue-as-a-shaded-area-in-gnuplot/60624922#60624922

virtual std::string legend_string(std::string_view legend);

// Take a number of legends from the range [legends_begin, legends_end]

// and advance the legends_begin iterator.

// Objects might want to take care of more than one legend.

// They can overload this method to do that.

// If not, they can just inherit the simple legend_string method.

virtual std::string

legend_string(std::vector<std::string>::iterator &legends_begin,

std::vector<std::string>::iterator &legends_end);

virtual std::string data_string();

virtual std::string unset_variables_string();

public:

const class axes_type *parent() const;

class axes_type *&parent();

void parent(class axes_type *&parent);

void touch();

// Objects might have their own display name

// In this case, we use the display name for legends

// instead of the strings in the legends object

const std::string &display_name() const;

void display_name(std::string_view display_name);

protected:

std::string tag_{"axes_object"};

std::string display_name_{""};

class axes_type *parent_;