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Socoder -> Cobra -> Another rotation maths question |
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| Wed, 27 Jan 2010, 03:46 | |
HoboBen
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I'm using this code to transform points of a vector graphic by offset, origin, scale and rotation. It's mostly working except when I change the origin of rotation - a change in X origin works, but a change in Y origin doesn't quite (see image). I can't figure out a way to change my code so that it works for a change in Y origin without then messing up the result when I have a change in X origin.  Any ideas? Thanks very much. -=-=- blog | work | code | more code |
| Wed, 27 Jan 2010, 03:49 | |
Jayenkai
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I've just scanned it, not properly read what you're doing, but "If (ToReal(pt.x - svg.xorigin) <> 0.0) then" seems to be sticking out a bit. |edit| Upon a proper reading, never mind.. |edit| -=-=- ''Load, Next List!'' 
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| Wed, 27 Jan 2010, 03:52 | |
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HoboBen
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That's just to avoid a divide-by-zero error on the next line. (edit - though technically the else case should be Atan(INFINITY) instead - I've changed that now.)
-=-=- blog | work | code | more code |
| Wed, 27 Jan 2010, 04:01 | |
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HoboBen
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Hahahaha, I've got it!!! This always happens - I work on things for hours and get nowhere, then after posting here for help I solve it it minutes! Had to add this after sign = Sgn(theta)... If ToReal(pt.y - svg.yorigin) < 0.0 then theta = theta + 180 That's all there was to it. Wooo!  edit - In TransformX to fix an occasional problem around y=0, I needed: If (pt.y - svg.yorigin) < (-0.1 * Sgn(pt.x - svg.xorigin)) then theta = theta + 180.0 -=-=- blog | work | code | more code |
| Wed, 27 Jan 2010, 04:09 | |
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Jayenkai
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Hmm.. Seems a little odd, but ok! Also, still not sure why you're doing Result=ToReal() when the function's listed as integer... -=-=- ''Load, Next List!''
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| Wed, 27 Jan 2010, 04:16 | |
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HoboBen
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Code's just a bit sloppy as I'm prototyping... Going to change a lot of my integers to reals.
-=-=- blog | work | code | more code |
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