3.1.2.2
Picture Behaviors
[Caveat: this text is old WebCGM 1.0 text (test should be updated.)]
Picture behaviors describe to the viewer how to display the picture, which is the target of a hyperlink. Picture behaviors are based on the syntax and semantics of " Frame Target Names" defined in the HTML 4.0 Specification.
The reserved names listed below describe the various picture behaviors. All other Picture Behavior values shall be valid Frame Target Names as described in the HTML 4.0 specification. Frame Target Names must begin with an alphabetic character (a-zA-Z).
In what follows, the following conventions apply:
The following Picture Behavior values, except for _replace, are defined per HTML 4.0:
If the picture behavior value is any valid name string other than the above reserved names, (it begins with an alphabetic character (a-zA-Z)), remove the existing content (picture or document) from the frame whose name matches the string and display the specified content in the specified frame. If no frame exists by the specified name, the viewer shall load the designated content (picture or document) in a new window with the specified name.
In the case that a link is HTML to CGM, the picture behavior should not be included in any fragment specification. Rather, the effect should be achieved with HTML TARGET attribute on the link specification in the HTML, per the specifications in the HTML 4.0 Recommendation. CGM viewers shall ignore picture behavior specifications in URI fragments which are part of links from non-CGM content.
The following table summarizes the rules for other link types, CGM-to-HTML and CGM-to-CGM:
Behavior | CGM-to-HTML | CGM-to-CGM |
---|---|---|
_blank | The viewer shall load the designated document in a new, unnamed window. | The viewer shall load the designated picture in a new, unnamed window. |
_self | The viewer shall load the document in the same frame as the one containing the CGM picture that refers to this target. This is the default for CGM-to-HTML links. | The viewer shall load the picture in the same frame as the one containing the CGM picture that refers to this target. |
_parent | The viewer shall load the document into the immediate FRAMESET parent of the current frame in which the current picture is displayed. This value is equivalent to _self if the current frame has no parent. | The viewer shall load the picture into the immediate FRAMESET parent of the current frame in which the current picture is displayed. This value is equivalent to "_self" if the current frame has no parent. |
_replace | Not applicable. Default to _self. | The viewer shall display the designated CGM picture in the same rectangular area in the same frame as the picture which refers to this target. If the ending resource (CGM) is the same as the linking resource, the viewer does not reload the resource. This is the default behavior for CGM-to-CGM links. |
_top | The viewer shall load the document into the full, original window (thus canceling all other frames). This value is equivalent to _self if the current frame has no parent. | The viewer shall load the picture into the full, original window (thus canceling all other frames). This value is equivalent to _self if the current frame has no parent. |
target | The viewer shall load the document into the frame identified by "target". If no matching frame can be found, the viewer shall load the designated content document in a new window with the specified name. | The viewer shall load the picture into the frame identified by "target". If no matching frame can be found, the viewer shall load the designated content document in a new window with the specified name. |