Usable Screen Sizes

Within the group some members including myself have raised an issue  
on the two properties currently submitted for inclusion in the Core  
Vocabulary that should define the portion of screen that is available  
while browsing.

This is what is in the text now.
Description: The total number of addressable pixels in the vertical  
direction in the current orientation of the device left after any  
reduction of the number resulting from manipulations of the current  
delivery context - e.g. browser chrome, operator transcoding/gateway  
etc.

Measurement: The result is derived from knowing the adjustments that  
the various components of the delivery context apply to the known  
underlying actual dimention provided by the underlying hardware.



There is a doubt that will be hard if not impossible to measure the  
values in a repeatable way and that the interpretation and values  
will vary. We want to make sure that the interpretation is common  
among all the implementors and users of a DDR. Without consistency  
the vocabulary and the standard would lose importance.



My suggestion is that we modify this proposed property into something  
less broad and easier to measure or drop it. What I think could be  
reasonable is to define the "Usable screen width" as the physical  
screen width minus the scroll bars when they are displayed and the  
"Usable screen height" as the physical screen minus the title bar,  
the scroll bar at the bottom and the space for the softkeys at the  
bottom. Some browsers and devices display and hide the title bar and  
scroll bar depending on a number of factors. If we are going to have  
the physical screen size in the DDR, redefining the "Usable size"  
according to scroll bars, title and softkeys should be of help.

I'm open to other suggestions, of course.

Another option remains to leave them out of the Vocabulary.



- Andrea