XSL-FO: corresponding margin and space properties

The XSL CR spec says:

    5.3.2 Margin, Space, and Indent Properties

    The "space-before", and "space-after" properties (block-level 
    formatting objects), "space-start", and "space-end" properties 
    (inline-level formatting objects) are handled in the same way as 
    the properties immediately above, but the corresponding absolute 
    properties are in the set: "margin-top", "margin-bottom", 
    "margin-left", and "margin-right".
    ...

I understand that in lr-tb writing-mode the correspondences are:
    space-before = margin-top    (block-level)
    space-after  = margin-bottom (block-level)
    space-start  = margin-left   (inline-level)
    space-end    = margin-right  (inline-level)

However, here is not clear about components of the compound space
datatype. How about space-before.precedence and space-before
.conditionality when margin-top is specified?

Naturally, the precedence and conditionality values should take the 
initial values.

    space-before.minimum = value_of(margin-top)
    space-before.optimum = value_of(margin-top)
    space-before.maximum = value_of(margin-top)
    space-before.precedence = "0"
    space-before.conditionality = "discard"

But there is a problem. The space.conditionality="discard" feature
is not expected when margin properties are specified (at least in the 
CSS model). For compatibility with CSS it should be modified as:

    space-before.minimum = value_of(margin-top)
    space-before.optimum = value_of(margin-top)
    space-before.maximum = value_of(margin-top)
    space-before.precedence = "0"
    space-before.conditionality = "retain" <--- CSS margin is not "discard"


I have another one question -- about "auto" value of margin properties.
The value "auto" is defined in the CSS-derived margin properties,
but in the corresponding space and indent properties, the "auto" value 
is not defined.
The "auto" value of margin properties should be ignored?


Regards,

Shinyu Murakami
Antenna House XSL Formatter team
http://www.antennahouse.com

Received on Monday, 25 June 2001 13:05:10 UTC