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<DIV dir=ltr align=left><SPAN class=637445521-25042014><FONT color=#0000ff
size=2 face=Arial>besides everything said, this nails it down : "... but
declaring the Metaverse to simply end at 0 seems very random.
"</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=637445521-25042014><FONT color=#0000ff
size=2 face=Arial>I should make this my new email signature .. well said, Jim
.. it's the metaverse .. no boundaries ? with future
physics</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=637445521-25042014><FONT color=#0000ff
size=2 face=Arial>not working below -0 ther will be no underwater worlds .. no
submarines .. even boat creators must keep an eye that the </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=637445521-25042014><FONT color=#0000ff
size=2 face=Arial>engine does not move below -0 ; ?</FONT></SPAN></DIV>
<DIV><FONT color=#0000ff size=2 face=Arial></FONT> </DIV>
<DIV><SPAN class=637445521-25042014></SPAN><FONT face=Arial><FONT
color=#0000ff><FONT size=2>b<SPAN class=637445521-25042014>est
regards</SPAN></FONT></FONT></FONT></DIV>
<DIV><SPAN class=637445521-25042014></SPAN><SPAN
class=637445521-25042014></SPAN><FONT face=Arial><FONT color=#0000ff><FONT
size=2>W<SPAN class=637445521-25042014>ordfromthe
Wise</SPAN></FONT></FONT></FONT><BR></DIV>
<DIV lang=de class=OutlookMessageHeader dir=ltr align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>Von:</B> opensim-dev-bounces@opensimulator.org
[mailto:opensim-dev-bounces@opensimulator.org] <B>Im Auftrag von </B>Jim
Williams<BR><B>Gesendet:</B> Freitag, 25. April 2014 02:17<BR><B>An:</B>
opensim-dev@opensimulator.org<BR><B>Betreff:</B> Re: [Opensim-dev] Negative z
values<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV dir=ltr>Seems to me that 0 is a completely arbitrary number and that a
cut-off for any reason other than hardware/mathematical limitations is
unwarranted. I could see taking an "oh well" attitude about things that
don't work with -z, but declaring the Metaverse to simply end at 0 seems very
random.</DIV>
<DIV class=gmail_extra><BR><BR>
<DIV class=gmail_quote>On Thu, Apr 24, 2014 at 6:46 PM, Melanie <SPAN
dir=ltr><<A href="mailto:melanie@t-data.com"
target=_blank>melanie@t-data.com</A>></SPAN> wrote:<BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">I
have never seen a Z < 0 build. I see lots of problems that may
be<BR>possible with this, but I think that quite beautiful and
interesting<BR>builds could make use of this and would support keeping it.
The<BR>change in the viewer is recent and likely trivial to undo.<BR><BR>-
Melanie<BR><BR>On 25/04/2014 00:32, Justin Clark-Casey wrote:<BR>> Hi
folks. Historically, whether by accident or design, OpenSimulator has
allowed negative Z values for terrain, objects<BR>> and avatars (e.g.
<130, 50, -45>. I have seen people use this facility to build
fully underwater or partially<BR>> underwater structures (e.g. oil rigs,
sunken ships, etc.) which are conceptually far below the water line without
having<BR>> to set that water line at a level that may be way above that of
surrounding regions.<BR>><BR>> However, at least on Singularity 1.8.5 on
Linux, fog effects do not work properly when z < 0, where all view
distances<BR>> have very high fog no matter what the fog settings.
This may be a recent change - I remember fog working properly at<BR>>
negative z values in the past, though the fog issue still occurred past a
certain -ve z. There may be other issues of<BR>> which I'm not aware.
Arguably, these are not bugs since the Linden Grid does not allow z <
0 (though one could make the<BR>> same argument for var regions,
etc.).<BR>><BR>> With in-world testing of current development code,
BulletSim appears to have a hard-coded check where I can't move my<BR>>
avatar below z == 2 whether terrain is z < 0 or not (this should probably
at least be fixed so z = 0 is possible). ODE<BR>> has allowed and
still allows the avatar to descend to negative depths.<BR>><BR>> One
argument is that in the light of such bugs, it would be better to consistently
enforce z >= 0 and require people<BR>> with -z builds to either move
them and the water level up using OpenSimulator commands (e.g. "translate
scene") or never<BR>> update their OpenSimulator
installation.<BR>><BR>> However, I think there is a real value in
keeping the -ve z ability. It allows people to extend deep water
builds<BR>> without having to adjust any neighbouring sims for consistency
(which they may not have control over). I'm sure it's<BR>> possible
to address the viewer-side issues. OpenSimulator could have an
allow-negative-z flag which is false by default<BR>> to make it explicit
that using -ve z may have issues at this time. I accept this is a more
complicated solution than<BR>> enforcing z == 0, though enforcing z == 0
will also requires many changes to the current code where bounds are not
checked.<BR>><BR>> If my experience is unusual and -z builds are very
rare then there's more of a case for enforcing z >= 0.<BR>><BR>>
Thoughts?<BR>><BR>_______________________________________________<BR>Opensim-dev
mailing list<BR><A
href="mailto:Opensim-dev@opensimulator.org">Opensim-dev@opensimulator.org</A><BR><A
href="http://opensimulator.org/cgi-bin/mailman/listinfo/opensim-dev"
target=_blank>http://opensimulator.org/cgi-bin/mailman/listinfo/opensim-dev</A><BR></BLOCKQUOTE></DIV><BR><BR
clear=all>
<DIV><BR></DIV>-- <BR>No essence. No permanence. No
perfection. Only action. </DIV></BODY></HTML>