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Re: [CSS3] Box Model Terminology

From: Christoph Päper <christoph.paeper@crissov.de>
Date: Tue, 18 Mar 2008 00:04:24 +0100
Message-Id: <CB0E7196-5507-4CAE-8FAF-01A049A06226@crissov.de>
To: CSS Style <www-style@w3.org>

JFTR: English is not my native language and my practical experience  
with non-European writing systems is quite limited.

Fantasai, 2008-02-27:
> Dimensions
>
>   width                                              logical width
>   height                                             logical height
>
>   * The distinction between "width" and "logical width" can be more  
> explicit
>     by using the term "physical width", and likewise for height.
>   * An alternative set of terms would be "relative width" vs  
> "absolute width".

I think these are good enough. I like "physical"/"logical" better,  
but can't say why.

   width            run size,    run length;
                    inline size, inline length;
                    line size,   line length.
   height           flow size,   flow length;
                    block size,  block length.

A "line" or "run" being a sequence of characters, and a "flow" being  
a sequence of such character sequences.

You could also introduce synonyms with new specific differences in  
meaning, like "breadth" and "extent".

> Directions
>
>   n/a (refer to 'direction' property)                 inline direction
>   n/a (refer to 'writing-direction' property)         block direction

I actually prefer "flow direction" to "block direction".

By the way, I don't like 'rtl'/'rl', 'ltr'/'lr', 'ttb'/'tb' and  
'btt'/'bt', because they're more cryptic than most other CSS  
keywords. I believe 'rightward'/'rightwards', 'leftward'/'leftwards',  
'downward'/'downwards' and 'upward'/'upwards' were a better choice,  
even if these words are not that frequent in modern English.

> Sides (from LTR reference)
>
>   top                                                 before
>   left                                                start
>   right                                               end
>   bottom                                              after

These are already established, I think.

   middle (vertical)                                  half-flow
   center (horizontal)                                half-line

I don't see where these would be needed, though.

> Layout Modes
> ------------
>
>   "in vertical text", "in vertical layout",
>   "when writing-mode is vertical", etc.               in vertical  
> writing mode
>
>   "in horizontal text", "in horizontal layout",
>   "when writing-mode is horizontal", etc.             in horizontal  
> writing mode


So I assume the |writing-mode| property now takes two values, one of  
which is either 'vertical' or 'horizontal'. (It used to take 'lr-tb',  
'rl-tb', 'tb-rl', 'tb-lr' in the withdrawn 2003 Text CR.)

>   an English (LTR-TB) block:
>
>                  <---- width / logical width --->
>
>                             top side/
>                            before side
>                  +------------------------------+                  A
>      left side/  |   ---inline direction --->   |  right side/     |
>      start side  |  |                           |  end side        |
>                  |  | block      * horizontal * |                 
> height/
>                  |  | direction  *writing mode* |             
> logical height
>                  |  V                           |                  |
>                  +------------------------------+                  V
>                             bottom side/
>                              after side

There have been scripts with alternating inline direction which may  
or may not affect glyph orientation. (Some very old Old Greek samples  
for example.) I suppose CSS will not support these in level 3, but  
suggest to consider it for later updates.

There are examples where texts with a downwards block direction are  
bottom-aligned and others with an upwards block direction and top- 
alignment, e.g. some chat systems or logs. OTOH this usually does not  
apply to lines but blocks (like paragraphs). Anyway, the progression  
of lines alias flow progression is not always the same as block  
progression.

   a vertical Japanese block (downward leftward):

                  <----- width / flow length ---->

                             top side/
                            start side
                  +------------------------------+                  A
      left side/  |    <---flow direction----    |  right side/     |
      after side  |                           |  |  before side     |
                  |  *  vertical  *     inline|  |                 
height/
                  |  *writing mode*  direction|  |             flow  
length
                  |                           V  |                  |
                  +------------------------------+                  V
                            bottom side/
                             end side

PS: Sorry if not everything above makes sense, I'm a little tired.
Received on Monday, 17 March 2008 23:04:24 GMT

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