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Posted: **Sun Aug 28, 2016 10:32 pm**

I found a minor undocumented feature.
This concerns [[...]] and order of evaluation of adjustment when there is randomness in the adjustments.
I'm using 3.0.9(v41) on Mac OS X.
MWE:

Code: Select all

startshape S[a -.5]

shape S{
	ONE[]
	TWO[x 1.5]
	THREE[x 3]
	}

shape ONE{
	SQUARE[b .5]
	SQUARE[[x .5 y .5 s .5 sat 1 b 1 ]]
	SQUARE[[s .5 x .5 y .5 sat 1 b 1  h 120]]
	CIRCLE[[x .5 y .5 s .5  sat 1 b 1  h -120]]
	}

shape TWO{
	SQUARE[b .5]
	SQUARE[[x .5 y .5 s .5 sat 1 b 1 ]]
	SQUARE[[s .5 x .5 y .5 sat 1 b 1  h 120]]
	CIRCLE[[x .5 y 0.5..0.501 s .5  sat 1 b 1  h -120]]
	}

shape THREE{
	SQUARE[b .5]
	SQUARE[[x .5 y .5 s .5 sat 1 b 1 ]]
	SQUARE[[s .5 x .5 y .5 sat 1 b 1  h 120]]
	CIRCLE[[x .5 y 0.5..0.5 s .5  sat 1 b 1  h -120]]
	}

Posted: **Mon Aug 29, 2016 1:47 pm**

I found the bug and it is trivial for you to work around until I release a fix. Context Free tracks whether shape adjustments are compile-time evaluated or runtime evaluated. Constants are evaluated at compile-time and the random functions are evaluated at runtime. But CF also performs an optimization when it sees consecutive adjustments x foo y bar. It converts the two adjustments to a single adjustment x foo bar. The bug is that if bar is runtime evaluated, CF drops this information and treats foo bar as if it was compile-time evaluated.

The work-around is simple. Just replace x foo y bar with x foo bar in your cfdg file and the buggy merging code will be bypassed. CF will correctly notice that foo bar is runtime evaluated because bar is runtime evaluated.

Posted: **Tue Aug 30, 2016 3:13 am**

Ah OK - I didn't try that. My workaround was to go via another shape. Not the most efficient way to do it, but it works.

... but I'm clearly not into efficiency - I realised after uploading "weather" that I coded degrees-to-degrees conversion into all my calls to "atan" via atan(...)/atan(1)*45. I've got to get better at RTFM.

Oh and thanks.

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