The bug that lead to my bug report for v3.1g 
22. March 2000 to povray.bugreports with the title:
"Macros and Arrays in POV-Ray v3.1":

news://news.povray.org/38d9867f%40news.povray.org

- is still alive in v3.5.


Here's 3 sample scripts that will force this bug
to surface:



By Nigel Stewart:

#macro Macro1(A)
  #local B = A;
  B
#end

#macro Macro2(C)
  #local D = C;
  D
#end

#local Z = Macro1(Macro2(1.0));



By Tor Olav Kristensen:

#macro Dummy(NN)

  NN

#end


#declare M1 = array[2] { <1, 2>, <3, 4> }

#declare M3 = array[2]

#declare M3 = Dummy(M1)



By Ron Parker:

#macro Macro2(C)
  #local D = C;
  D
#end

#local Z =
Macro2(Macro2(Macro2(Macro2(Macro2(Macro2(Macro2(Macro2(5.0))))))));
  
#debug str(Z,5,5)  
#debug "\n"



A workaround for the macro in Ron's sample code is
to add a pair of parentheses around the returned
local variable. (Same solution for Nigel's code.)

Like this:

#macro Macro2(C)
  #local D = C;
  (D)
#end


For my example there's no known "straight forward"
workaround to make the macro return a local array
variable in a "safe" way.


Tor Olav

Post a reply to this message