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devguide-13.html
The class HierarchyNode
devguide-9.html
The Document and Graphics Classes
devguide-15.html
The class Selectable
The class
Protocols
While sharing a common interface, the various types of graphics objects
provide a variety of additional capabilities and interfaces. The class
Protocols
defines some flags that indicate the presence of certain
standard extensions. These flags are boolean class variables with names
of the form `
is_
*' or `
has_
*'. By default all of these flags
are false. Derived classes are expected to set the appropriate flags.
The standard flags are:
has_properties
True, iff object can have properties. If true, the object must
implement the methods
AddStyle
,
Properties
,
SetProperties
,
ObjectChanged
and
ObjectRemoved
.
The class
devguide-16.html#N2
Primitive
provides this interface.
has_fill
True, iff object can have fill properties. If true,
has_properties
must also be true. In addition, the object
must implement the method
Filled
and the method
SetProperties
must accept the fill properties.
The class
devguide-16.html#N2
Primitive
provides this interface.
has_line
True, iff object can have line properties. If true,
has_properties
must also be true. In addition, the object
must implement the method
LineWidth
and the
method
SetProperties
must accept the line
properties.
The class
devguide-16.html#N2
Primitive
provides this interface.
has_font
True, iff object can have a font. If true,
has_properties
must also be true. In addition, the method
SetProperties
must accept the font properties.
is_Bezier
is_Rectangle
is_Ellipse
is_Text
is_Image
is_Eps
Indicate the type of object.
is_Compound
True, iff the object is a compound object.
is_Group
True, iff the object is a group. A group is a compound object. A
group object can be
ungrouped
, that is, the user can issue
a command that replaces the group with its children, which
become direct children of the group's parent. To this end, a
group must provide the method
Ungroup
. (see the
document method
UngroupSelected
)
is_Blend
True, iff the object is a blend group.
is_curve
True, iff the object can be converted to a
PolyBezier
object. If true, the object must implement
the methods
devguide-11.html#N6
AsBezier
and
Paths
.
Skencil treats the PolyBezier as a kind of `common denominator'
for blending. For instance, if you try to blend a rectangle and
an ellipse, both are converted to beziers and the beziers are
blended.
is_clip
True, iff the object may be used as a clip mask. If true, the
methods
devguide-15.html#N5
Hit
and
devguide-11.html#N9
DrawShape
must
accept an additional boolean parameter
clip
indicating
whether the object is used as a clip mask.
devguide-13.html
The class HierarchyNode
devguide-9.html
The Document and Graphics Classes
devguide-15.html
The class Selectable
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