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Source alpha in spat5.oper~ on Windows

Hi all,

I’ve run into a strange issue when trying to dynamically trying to adjust the alpha of individual sources in oper. As soon as I send a {/source/1/color/alpha $1} message to oper (where 0 <= $1 <= 1), the source becomes completely transparent. The strange thing is that this is only an issue on windows, everything works as expected on a mac. Also, other settings like {…/aperture/visible $1} work fine.

Does anyone have any idea what could be going wrong here or how I can fix it? example code below… thanks!

<pre><code>
----------begin_max5_patcher----------
1880.3oc4a0sjhhCE9Z6mBVp8psZUHD.ybyt6ywLSYgRTyrHghD5tmcq4cey
O.BJXiJf1UWUKT8IPx47kuyIIjb9umlXth9FlYZ7EiuZLYx+8zjIJQRASx++
Il6CdacT.S8Xlw3Woq9g4y5h3323Jwrj.t6LZBN03uHwD9qD9NiuYNmQyRWi
mGmseknHmuYV7lBIj3HLWUq14BEUx5cj3sKSwq4ZsxdAZl0yFNd9xa.fi91L
KiuenlnY7hpBlKUKh+yDrtdDMbkekuLITo9BSZpcgpwBdAGtTHRnDKC37Txp
LtFklThJRkMMXOliSWhiCVEoZGKUY+5omJt9qmd91.1eapgciXFncLywyUhR
1HOEXgl4dVHytMHiDyaDo7MuB6iS2tU.RWX2ego3aoLEXw09xTrgHyxVuk9y
KzP2iYrfs3S5IK7E9i4uPXDQCX761OaTH0tTZY2cDIFullEyq1cegb..vVge
1Jpfi6kibMCatVWCGfEQBwomkCrIhFvEJQRF+cnFtJJgsk9liN9vMYfLx+pD
JgrFXJf9loHrUgNdd3fltOPYvduKR.T8w5+4Lt6fyEgbUP71VbTbFeGk0zHZ
57fnjcABmkKMLXNrjeyw8cvkKzC.BM6un7IFhAX3R0e2OYBjEyHrkDFKq4.l
VmwuGrP6V.T2fnagMzrka6YVs8ENzGMx3FRD9EbJiPiq.rSLCRRpHdRkWQhR
+fppnEOWJhDqE4UJJEKiRpee2RoAoBTfKffrTk1a9lGz7P0PEwbhyHJUQKTz
ekqRpdlXAcVLAl05WV1AVTbExDRGGUcyCp3TvEVGvUQO+1H55+AGVoGRfqI3
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2KBugmWbBIN9HTjSSZuvTx1cm4cWQEEt+b0spD1xrXcoKEbB9R4r.q+bAQQ4
tu0q92BhIhfzXNQ2E.rJKTGfbGacJMJpl8pK4kFJITvwWiekDx2oZnpjAwiS
RJHQlk8xgjshvG0kwC1xpKgw+oFzqHJaUtO7RNdeRjvJp+.BuCBiy1Qekk+f
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sn9lCf9ddUa7Zy6BVoflFgts3v.cHBfuWkAg7pFu3zXwVUJoR.W2ElEx0qrX
RwHNWCZSmIv6DJC2HdeX5nA3Pog3.l8rfCJLgYeuUPBzFHANOHkOWEndHKWn
dkdmEipB6MET77ifeBzVqiWuvuUYwgQ3kQ33sZOPuEs8LgA7f7gcEKwBsPN.
gu7hdhoxKRYVh44a0g+fhGFpdeW4E6xpCJpbTdEIe.HReG4mKT0XGpGXYyac
bYpQuz+r57edNOaL016zhL99cjYBGblIrv68NvLc+rxLc+3yLcl46M3bSqpK
uYb4lvOwQMm5HdSewuoK.hwtTK7FjK9CGK0cnYoNdf6FK04SMKE7gOF5hAOD
pyh6F4D7YlbB7Tegplu7gKHJbvChBbua7T6O0AQkW7EbxExw6AxK1.AM7C4X
8C9x3W3c2XoVepYoHIiyxokq28Pp01lqy+gzNY6tZ8yqYqW8iOn487p8c5ni
680wTLXs07z9d+2OPVssIptucDMHTtyYFLL2vww207Z+Bk101.UKTGvP6qx8
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wFnFTzAYbrJtd4agnXtmU0ghcbs5V8pdi3P7aUNmDO.PfcOhAtWDF.Z.CNb9
HjKbpkc8VYExxaFbzqMKmtVvHMpaPgpSCT4wE4qktscet4WrVrniZgbjnASK
DAq6HV3OjZgSG0BEmZ3TC3igZ31UlAZH0hNyOgCoVf5pVLj9ptVclXLjfg7i
C9HnFfGC0v4wPMfOFpg6igZ30CpQtvhSMZWSPjK535sMhtJH5nyXWSmluqOC
SttLv.3p2AWj6.kAFVVi8AKGTICLtzCUdNbTlWE186oJ2xdDysFKcm4hApmE
cGRslfDbp7XfeC8v4vhitq01E0q8vH+dLsA36RytxDpC.cySNrd057t6oETt
8MZ4EDx8QMsfJPhAMufPvw1I29FSKnBXwsFAo27.pkXbpmn92JPCAGOOlbf3
j4ufpM+k1l6xgYtbBV20FRML762RV8SaY2g1pvzuslBB5hYU8aZbCskSmZKX
uzVvwCBQcno76iVx0ZrLJ+tzSUnN2TKgFMaB0IJQuXStcok5CdNxezPutvxQ
mRy0g3OJ0FkMxQoz3Qoy3ooxX6ow3wovnZgnsk5hO8qm9eHdRdK.
-----------end_max5_patcher-----------
</code></pre>

UPDATE: It looks like there’s a bug where the alpha value is scaled down by a factor of 10000x. If I send a value of 10000 the source becomes fully opaque, and 0 is transparent, so the normal 0-1 range was just too small to register any noticeable difference…

Thanks for the feedback. This should be fixed in the latest release (v5.3.6).

NB: you could also use the message “/source/[index]/opacity $1” (with values in [0 - 100] range), which presumably was working OK in previous versions.

Let us know if there’s still any issue.
Best,
T.

1 Like

Thanks Thibaut, I just switched to the /opacity message and that works fine on both mac and windows.
cheers,
-eric