[reportlab-users] Transparent PNG support

[Robin Becker]

Tim Roberts wrote:

> Tim Roberts wrote:

>> ...

>> This is drawing in units of 1 pixel.  You could reduce the stroke width

>> to 0.5 and do twice as many steps.

>>   

> 

> Sorry, that should read "..in units of 1 point".

> 

In pdf canvas land colors are float numbers 0-1. I'm not certain exactly what 
the resolution is in colour space, but it's probably better than 1/255. The 
spatial resolution is 1/2**16 (I think) as numbers are 16.16 fixed point inside 
acrobat (or used to be) the 1.6 manual says floats are now used, but the fixed 
point numbers are used for screen display and fonts. Anyhow, you should be able 
to get much better variation with acrobat than with 8 bit transparency 
variation. Of course we could do shading patterns if we had those in reportlab, 
but I think it unlikely they're going to appear any time soon :(
-- 
Robin Becker