ArtX Point mark.

Members:

IG_ARTX_point_color_get	Queries the Color attribute.
IG_ARTX_point_color_set	Updates the Color attribute.
IG_ARTX_point_create	Creates point mark.
IG_ARTX_point_opacity_get	Queries the Opacity attribute.
IG_ARTX_point_opacity_set	Updates the Opacity attribute.
IG_ARTX_point_width_get	Queries the Width attribute.
IG_ARTX_point_width_set	Updates the Width attribute.
IG_ARTX_point_x_get	Queries the X coordinate.
IG_ARTX_point_x_set	Updates the X coordinate.
IG_ARTX_point_y_get	Queries the Y coordinate.
IG_ARTX_point_y_set	Updates the Y coordinate.