[pstricks] Ghostscript 9.53 transparency operators

[Herbert Voss]

Am 30.03.21 um 14:17 schrieb Alexander Grahn:
> the new PostScript transparency operators in Ghostscript are still not
> used, despite the definitions at the top of pstricks.pro.
>
> The warning
>
>     **** WARNING: .setopacityalpha is deprecated (as of 9.53.0) and will be removed in a future release
>     **** See .setfillconstantalpha/.setalphaisshape for the improved solution
>
> written to the terminal multiple times indicates that old operators are still
> being used.

Alexander,

this is not really true: the _old_ operators are _not_ used. If there is 
a gs version > 9.52
pstricks.pro defines it's own .setopacityalpha and uses the old 
definitions for old
gs versions.  The warnings are wrong in this case, but GhostScript has 
no check for
this.

If I run your example with MiKTeX's up-to-date mgs.exe (9.25) I'll get


Error: /undefined in --load--
Operand stack:
    .setfillconstantalpha.bak   .setfillconstantalpha


The reason why I still use the old function names is the fact that the
PSTricks code must not be changed.

And the warnings will go away hopefully for 9.54

Herbert