In addition to the methods listed above, class
    RVG::Group also implements the styles method, the shape methods and the transform methods.
RVG::Group.new [ { |self| drawing method calls } ] -> group
Drawing objects defined within a group share the transforms
    and styles defined on the group. Groups can be nested
    arbitrarily deep. RVG::Group.new is commonly
    invoked within another group or RVG object by calling the
    g method (RVG#g,
    RVG::Group#g) , which nests the group within
    the target object.
RVG::Group.new yields to a block if one is
    present, passing self as an argument.
An RVG::Group object
See the tutorial for examples of the most common uses of groups. In this example, I use RVG::Group.new to construct a "stand-alone" group that is then referenced in multiple calls to the use method.
group.desc ->
    string
    group.desc = string
desc attribute to
    assign a text description to the group.
  group.metadata ->
    string
    group.metadata = string
metadata attribute to
    assign additional metadata to the group.
  group.title -> string
    group.title = string
title attribute to
    assign a title to the group.
  group.g [{|grp| ...}] -> group
Calls new to construct a new group and nests it within the target group. Yields to a block if one is present, passing the new group as an argument.
Returns the new group, so other methods in this class can be chained to this method.
group.image(raster_image, width=nil, height=nil, x=0, y=0) -> image
Calls RVG::Image.new to construct an image and adds it to the group.
Returns the new image, so RVG::Image methods
    can be chained to this method.
group.rvg(width, height, x=0, y=0) [{|new_rvg| ...}] -> rvg
Calls RVG.new to construct a new RVG object and adds it to the group. See the rvg method in the RVG class.
The RVG object, so other RVG
    methods can be chained to this method.
group.text(x=0, y=0, text=nil) [{|text| ...}] -> text
Calls RVG::Text.new to construct a text object and adds it to the group. Yields to a block if one is present, passing the new text object as an argument.
The RVG::Text object, so other
    RVG::Text methods can be chained to this
    method.
group.use(obj, x=0, y=0, width=nil, height=nil) -> use
Calls RVG::Use.new to
    constructs a use object and adds it to the RVG
    object.
When the referenced argument is an RVG object, width and height can be
    used to specify the width and height of the viewport. If
    present and non-nil, these arguments override any width and
    height specified when the RVG object was created. You must
    specify the viewport size either when creating the RVG object
    or when referencing it with use.
See RVG::Use.new
The RVG::Use object, so other
    RVG::Use methods can be chained to this
    method.