From the little information you have given us, I'd guess that the arithmetic expressions in the arguments to colorAllocate return values outside the range 0..255.

But please provide a runnable, minimal example that demonstrates how stuff doesn't work.

Perl 6 - the future is here, just unevenly distributed

In reply to Re: allocating/deallocating colors with GD module. by moritz
in thread allocating/deallocating colors with GD module. by Anonymous Monk

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