Fixing 3.1.2.2, Picture Behaviors
The language in 3.1.2.2 is a mess. There are unspoken assumptions about source
and target formats (CGM or HTML), and that raises questions about the cases
where the formats are not as assumed. I tried to come up with some well-defined
specification of all cases.
Here is a table of all the "picture behavior" keywords, in different
source-to-destination types for links. Currently there are no restrictions on
which behaviors can be used. Unless we intend to specify such, we need to make
sure that the behavior is well defined for all combinations.
Notes:
- I use "document" for HTML, "picture" for CGM.
- The entry in quotes in each row is the verbatim text from WebCGM (with "shall"
replacing "should"). I have put it where it seems most applicable.
- The only significant changes are R4 (Row 4), C1 and C2. Otherwise I have
just substituted "document" for "picture", or vice-versa.
- While the means of achieving the specified action might be unclear (how
do browser and WebCGM viewer interact to achieve the desired effect?), it
seems to me that the cases are all well specified and achievable now. Agreed?
- If that's the case, then the text in 3.1.2.2 could be minimally repaired
by substituting "source (picture or document)" or "target (picture
or document)" in all of the appropriate places. And adding caveat to
"_replace" (same as _self), if either source or destination is not
CGM.
- More verbosely, we could just put this table in there (there is a lot of
redundancy in the table).
Picture behaviors and different source-to-destination
types. |
|
H-to-C |
C-to-H
|
C-to-C |
_blank |
The viewer shall load the designated picture in a new, unnamed
window. |
"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 picture in the same frame as the
one containing the document that refers to this target. |
"The viewer shall load the document in the same frame
as the one containing the CGM picture that refers to this target."
|
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 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. |
"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 |
As _self (_replace was invented by WebCGM for C-to-C cases.) |
As _self (_replace was invented by WebCGM for C-to-C cases.) |
"The viewer shall replace the current CGM picture by
the designated CGM picture in the same rectangular area in the same frame
as the picture which refers to this target. This is the default behavior." |
_top |
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. |
"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. |
|