Re: TikZ and wrong drawing order

[Hans Hagen <pragma@wxs.nl>]

On 6/11/2015 10:14 PM, Mojca Miklavec wrote:
> On Thu, Jun 11, 2015 at 7:59 PM, Aditya Mahajan wrote:
>> On Thu, 11 Jun 2015, Mojca Miklavec wrote:
>>
>>> Hi,
>>>
>>> I would like to ask for help for either finding a fix or some clever
>>> workaround for the following problem.
>>>
>>> If I use a TikZ picture as item symbol and additionally use background
>>> text, then the first symbol in itemize environment gets covered by the
>>> background. Here's an example:
>>>
>>> \usemodule
>>>     [tikz]
>>>
>>> \definesymbol[1]
>>>     [{\tikz\shade[shading=ball,ball color=blue] (0,0) circle (.2cm);}]
>>>
>>> \definecolor
>>>     [backcol]
>>>     [s=1,a=1,t=0.1]
>>>
>>> \starttext
>>>
>>> \startframedtext[width=4cm,background=color,backgroundcolor=backcol]
>>> \startitemize
>>> \item one
>>> \item two
>>> \item three
>>> \stopitemize
>>> \stopframedtext
>>>
>>> \stoptext
>>
>>
>> Workaround (though I have no idea why this should work).
>
> Does it also work if you use the following?
>
> \definecolor
>      [backcol]
>      [s=1,a=1,t=0.95]
>
>> Use
>>
>>     background={foreground,color}
>>
>> I wanted to test background={color, foreground}, but wrote the above by
>> mistake and it works!!!
>
> While it works in the sense that it gives a consistent look, it
> doesn't really lead to the desired result, at least not for me. The
> reason for using background colour in my case was to make text
> "visible" on a dark background photo. It doesn't really help if the
> main text gets hidden behind the semi-transparent layer.
>
> Unless you get different results than I do.

i suppose that tikz puts some pdf code in the output stream and this is 
likely to interfere with the way context deals with colors

a solution is:

{\red x\dontleavehmode\forcecolorhack\tikz\fill[color=blue] (0,0) circle 
(.2cm);x}

the

\forcecolorhack

is, well, a hack that fools the optimizer and \dontleavehmode is needed 
to get tex in the right mode

i have no time to look into the internals of tikz to see if a different 
trick is possible

Hans


-----------------------------------------------------------------
                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
     tel: 038 477 53 69 | voip: 087 875 68 74 | www.pragma-ade.com
                                              | www.pragma-pod.nl
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________