Re: [office] Giving 120%

[Andreas J Guelzow <aguelzow@math.concordia.ab.ca>]

On Fri, 2009-06-26 at 05:41 -0400, Patrick Durusau wrote:
> Andreas,
> 
> Andreas J Guelzow wrote:
> > "Specifies the proportion of blue RGB color components for a pixel
> > graphic object. The defined value range for the draw:blue attribute is
> > -100% (no blue) to 100% (full blue)."
> >
> > While I can understand that we don't want to discuss every single item,
> > shouldn't there be somewhere a common-sense filter?
> >
> > If -100% is no blue and 100% is (full blue), what is a value of 0%?
> >
> > Since we are using the percentage symbol here it would be nice if there
> > were at least some interpretation that this is a percentage of
> > proportion of something.
> >
> >   
> The inexact language was the result of my teasing out what was implied 
> in our prior versions.
> 
> draw:red, draw:green, draw:blue all control RGB channels. The color of 
> any image is set elsewhere and these three attributes represent 
> *changes* in the RGB channels for the rendering of that image.

Perhaps it should say just that in 1.2. Currently and with the proposed
change it does not say anything about the colour being determined
elsewhere. There are only 7 times draw:red is mentioned, 5 times in its
very brief description, once in the index and once that it is to be used
with style:graphic-properties.

With the respect to the latter we have 
The <style:graphic-properties> element specifies formatting properties
for draw, graphic, and frame elements.

Reading this, there is no way to know that "specifying" really means
"modifying".

Now reading the specs,

I add a table-cell, inside a draw:frame, inside a draw:textbox, inside
text:p with some text.
The draw:frame I can associate with a style via draw:style-name in which
I can set style:graphic-properties, in which I specify draw:red,
draw:green, draw:blue.

If I am told that draw:blue specifies "the proportion of blue RGB color
components for a pixel graphic object", I have to assume that we are
setting the proportion of full blue, so if it is 50% I get 50% of blue,
so #xxxx80 as the real color of the text (assuming it was default black
text).

Your message indicates that this may be wrong. (Of course the fact that
draw:blue refers to "pixel object" I have to wonder whether this applies
to the text at all, or whether I have to look at import of a black &
white bitmap image.

I hope you do not expect me to read Openoffice code.

Andreas


> 
> Thus, a setting of -100% for draw:red, allows no input from the red 
> channel. A setting of 0%, does not modify the value of the red channel 
> for this image. A setting of 100% sets the red channel to maximum.
> 
> What confused me was the use of "...*sets* the output of a blue color 
> space of a bitmap or raster graphic." Which to me meant that the color 
> was determined by this and other attribute. Not so, the color of a 
> graphic is *modified* by these attributes.
> 
> That is to say that a bitmap or raster graphic starts with a 
> defined/set, whatever, RGB space and these three attributes modify that 
> space.
> 
> Making what seems "obvious" to an author is very hard work and I for one 
> deeply appreciate the members of the Sun team and others working towards 
> that goal.
> 
> Hope you are having a great day!
> 
> Patrick
> 
-- 
Andreas J. Guelzow
Concordia University College of Alberta