https://wiki.secondlife.com/w/api.php?action=feedcontributions&feedformat=atom&user=Chromanoid+Xeno 2026-06-28T12:14:55Z User contributions MediaWiki 1.42.1 https://wiki.secondlife.com/w/index.php?title=LayerData&diff=60485 2008-03-29T18:33:53Z

<p>Chromanoid Xeno: /* Usage and Notes */</p> <hr /> <div>{{ProtocolNav}}<br /> ==Message Layout==<br /> &lt;pre width=80&gt;<br /> {<br /> LayerData High Trusted Unencoded<br /> {<br /> LayerID Single<br /> { Type U8 }<br /> <br /> }<br /> {<br /> LayerData Single<br /> { Data Variable 2 }<br /> }<br /> }<br /> <br /> &lt;/pre&gt;<br /> ==Usage and Notes==<br /> <br /> LayerData packets transmit terrain, wind, and cloud information using a custom IDCT routine similar to JPEG but with different coefficients. The data in these packets is stored in a proprietary format of 16x16 meter blocks.<br /> <br /> Type:<br /> <br /> - 76 : LLSurface (terrain)<br /> - 55 : LLWind (wind)<br /> - 56 : LLCloudLayer (Cloud)<br /> <br /> Data:<br /> <br /> :[patchgroupSize] - uint8<br /> :[unk] - uint8<br /> :[patchHeader]<br /> ::[patchSize] - uint8<br /> ::[unknown0] - uint32<br /> ::[unknown1] - uin16<br /> ::[unknown2] - 10 bit unsigned integer<br /> :[patchData]<br /> ::[zeroCode] - One bit. If 0, the data is zerocoded<br /> ::[hasData] - One bit, If 0, the entire patch is zeros.<br /> ::[data] - has a size of (patchSize % 16) + 2<br /> ::[data] ... - repeat until patchSize has been read<br /> :[patchHeader] ... - repeat until patchgroupSize has been read<br /> ::...<br /> <br /> The data then has to be decompressed, and I have no idea how this data is used.<br /> <br /> You may find some use from the psuedocode at [http://www.libsecondlife.org/wiki/LayerData LibSecondLife.org]<br /> <br /> [[Category:Messages]]</div>

Chromanoid Xeno