[x3d-public] X3D meeting agenda 18 FEB 2022: SpotLight angles, Volume Rendering component
Michalis Kamburelis
michalis.kambi at gmail.com
Fri Feb 18 15:50:52 PST 2022
(I'm sorry, resending again with smaller attachments to be accepted by
mailing list - base64 encoding makes attachments 4/3 larger.)
As for the discussed cutOffAngle/beamWidth defaults today. I know we
were supposed to think for a week, but I did some thinking already,
these are my thoughts and screenshots:
1. For cutOffAngle, my thoughts are clear. We should go for
cutOffAngle = pi/4. Because:
- it is what it was in X3D <= 3.2 (it's practically possibly zero
change for some browsers, possibly zero surprise for some authors).
- And it matches glTF outerConeAngle.
- I *do not* think it's a significant problem that real-life spot
lights are usually narrower (and Blender and Unity spot lights are
indeed narrower by default). The effect of cutOffAngle = pi/4 is
clearly visible by authors, they can adjust it.
2. For beamWidth, my thoughts are not clear, i.e. I'm not decided. I
see my options now as:
Vote 1: beamWidth = pi/2. This is what I originally advised, just
go back to X3D 3.2 defaults. It worked, it's a simple change (again,
possibly zero work for browsers, zero surprise for authors). It made
the SpotLight clearly visible.
Vote 2: beamWidth = pi/8. Because I do understand the desire to
express, by default, the situation that we have penumbra, which means
we prefer defaults with beamWidth<cutOffAngle. Having beamWidth =
cutOffAngle/2 = pi/8 seems the most natural number to do this.
Vote 3: beamWidth = 0. The biggest reason for this would be glTF
compatibility, their innerConeAngle = 0. My biggest concern with it is
that beamWidth = 0 makes the spot light actually hard to notice.
I am not decided between vote 1,2,3 but I think I'm narrowing down my
thoughts to these options.
Here are screenshots. I encourage everyone who participated today to
not just think about these numbers, but actually try them out in
existing X3D browsers on some existing scenes :) My screenshots may
well be biased by a particular scene I used now for testing. Go and
pick your own, and show us screenshots :)
To be clear: I can "live with" any situation when default cutOffAngle
is <= pi/4, and any beamWidth default is chosen. I.e. my "critical"
issue that sparked this discussion was that X3D 3.3/4.0 default
cutOffAngle is too large (pi/2) and it seems today that everyone
agrees it should be something smaller. We only wonder what should the
new defaults be. So I'm fine with almost any proposition we talked
about today :)
Regards,
Michalis
sob., 19 lut 2022 o 00:42 Michalis Kamburelis
<michalis.kambi at gmail.com> napisał(a):
>
> (resend with smaller attachments to be accepted by mailing list)
>
> As for the discussed cutOffAngle/beamWidth defaults today. I know we
> were supposed to think for a week, but I did some thinking already,
> these are my thoughts and screenshots:
>
> 1. For cutOffAngle, my thoughts are clear. We should go for
> cutOffAngle = pi/4. Because:
>
> - it is what it was in X3D <= 3.2 (it's practically possibly zero
> change for some browsers, possibly zero surprise for some authors).
>
> - And it matches glTF outerConeAngle.
>
> - I *do not* think it's a significant problem that real-life spot
> lights are usually narrower (and Blender and Unity spot lights are
> indeed narrower by default). The effect of cutOffAngle = pi/4 is
> clearly visible by authors, they can adjust it.
>
> 2. For beamWidth, my thoughts are not clear, i.e. I'm not decided. I
> see my options now as:
>
> Vote 1: beamWidth = pi/2. This is what I originally advised, just
> go back to X3D 3.2 defaults. It worked, it's a simple change (again,
> possibly zero work for browsers, zero surprise for authors). It made
> the SpotLight clearly visible.
>
> Vote 2: beamWidth = pi/8. Because I do understand the desire to
> express, by default, the situation that we have penumbra, which means
> we prefer defaults with beamWidth<cutOffAngle. Having beamWidth =
> cutOffAngle/2 = pi/8 seems the most natural number to do this.
>
> Vote 3: beamWidth = 0. The biggest reason for this would be glTF
> compatibility, their innerConeAngle = 0. My biggest concern with it is
> that beamWidth = 0 makes the spot light actually hard to notice.
>
> I am not decided between vote 1,2,3 but I think I'm narrowing down my
> thoughts to these options.
>
> Here are screenshots. I encourage everyone who participated today to
> not just think about these numbers, but actually try them out in
> existing X3D browsers on some existing scenes :) My screenshots may
> well be biased by a particular scene I used now for testing. Go and
> pick your own, and show us screenshots :)
>
> To be clear: I can "live with" any situation when default cutOffAngle
> is <= pi/4, and any beamWidth default is chosen. I.e. my "critical"
> issue that sparked this discussion was that X3D 3.3/4.0 default
> cutOffAngle is too large (pi/2) and it seems today that everyone
> agrees it should be something smaller. We only wonder what should the
> new defaults be. So I'm fine with almost any proposition we talked
> about today :)
>
> Regards,
> Michalis
>
> sob., 19 lut 2022 o 00:37 Michalis Kamburelis
> <michalis.kambi at gmail.com> napisał(a):
> >
> > As for the discussed cutOffAngle/beamWidth defaults today. I know we
> > were supposed to think for a week, but I did some thinking already,
> > these are my thoughts and screenshots:
> >
> > 1. For cutOffAngle, my thoughts are clear. We should go for
> > cutOffAngle = pi/4. Because:
> >
> > - it is what it was in X3D <= 3.2 (it's practically possibly zero
> > change for some browsers, possibly zero surprise for some authors).
> >
> > - And it matches glTF outerConeAngle.
> >
> > - I *do not* think it's a significant problem that real-life spot
> > lights are usually narrower (and Blender and Unity spot lights are
> > indeed narrower by default). The effect of cutOffAngle = pi/4 is
> > clearly visible by authors, they can adjust it.
> >
> > 2. For beamWidth, my thoughts are not clear, i.e. I'm not decided. I
> > see my options now as:
> >
> > Vote 1: beamWidth = pi/2. This is what I originally advised, just
> > go back to X3D 3.2 defaults. It worked, it's a simple change (again,
> > possibly zero work for browsers, zero surprise for authors). It made
> > the SpotLight clearly visible.
> >
> > Vote 2: beamWidth = pi/8. Because I do understand the desire to
> > express, by default, the situation that we have penumbra, which means
> > we prefer defaults with beamWidth<cutOffAngle. Having beamWidth =
> > cutOffAngle/2 = pi/8 seems the most natural number to do this.
> >
> > Vote 3: beamWidth = 0. The biggest reason for this would be glTF
> > compatibility, their innerConeAngle = 0. My biggest concern with it is
> > that beamWidth = 0 makes the spot light actually hard to notice.
> >
> > I am not decided between vote 1,2,3 but I think I'm narrowing down my
> > thoughts to these options.
> >
> > Here are screenshots. I encourage everyone who participated today to
> > not just think about these numbers, but actually try them out in
> > existing X3D browsers on some existing scenes :) My screenshots may
> > well be biased by a particular scene I used now for testing. Go and
> > pick your own, and show us screenshots :)
> >
> > To be clear: I can "live with" any situation when default cutOffAngle
> > is <= pi/4, and any beamWidth default is chosen. I.e. my "critical"
> > issue that sparked this discussion was that X3D 3.3/4.0 default
> > cutOffAngle is too large (pi/2) and it seems today that everyone
> > agrees it should be something smaller. We only wonder what should the
> > new defaults be. So I'm fine with almost any proposition we talked
> > about today :)
> >
> > Regards,
> > Michalis
> >
> > pt., 18 lut 2022 o 16:45 Michalis Kamburelis
> > <michalis.kambi at gmail.com> napisał(a):
> > >
> > > Vince,
> > >
> > > Sure, we can go over view3dscene nodes. Reading your links, I can
> > > submit these corrections:
> > >
> > > Looking at view3dscene nodes listed on
> > > https://docs.google.com/spreadsheets/d/1jXu52t7_5kdQY8CtEJBM8oU6PxzwQz93/edit#gid=140823416
> > > :
> > >
> > > 1. We have support for these nodes (they miss "x" in the respective column):
> > >
> > > Collision
> > > ComposedShader
> > > FloatVertexAttribute
> > > NurbsSet # though that's a bit unfair, and we just don't do (because
> > > we don't have to) do anything to support this node
> > >
> > > 2. We do not (and never did) support these nodes (their "x" in the
> > > respective column should be removed):
> > >
> > > PackagedShader
> > > ProgramShader
> > >
> > > 3. In your description on
> > > https://drive.google.com/file/d/1Ka1lR9laQiMPitRQWj3HULU2CKHqPFKF/view?usp=sharing
> > > , I suggest these edits:
> > >
> > > - Linus Desktop -> Linux Desktop :) We don't usually call it "Linus'
> > > Desktop" unless someone wants to praise Linus Torvalds in this
> > > imprecise way :)
> > >
> > > - We also support macOS, albeit it often lags in official releases.
> > >
> > > - "scripting uses the CastelScript language" -> while this is true for
> > > view3dscene, I would say more: "view3dscene allows to specify scripts
> > > using CastleScript https://castle-engine.io/castle_script.php . Castle
> > > Game Engine additionally allows to write code in Object Pascal that
> > > interacts with X3D and other models."
> > >
> > > - "CGE supports 3D scene authoring viewable in view3dscene." -> this
> > > may be confusing. Castle Game Engine editor actually creates designs
> > > that are more than X3D. So they are not viewable in view3dscene. It's
> > > the other way around -- "view3dscene allows to view various model
> > > formats, including X3D and glTF. Castle Game Engine editor allows to
> > > compose these models into larger designs, in JSON format specific to
> > > CGE."
> > >
> > > Regards,
> > > Michalis
> > >
> > > pt., 18 lut 2022 o 16:09 vmarchetti at kshell.com <vmarchetti at kshell.com>
> > > napisał(a):
> > > >
> > > > If there is time after Mantis discussion, a possible topic is review the node inventory and browser review information for view3dscene:
> > > >
> > > > view3dcene information review :
> > > > https://drive.google.com/file/d/1Ka1lR9laQiMPitRQWj3HULU2CKHqPFKF/view?usp=sharing
> > > >
> > > > Node inventory : https://docs.google.com/spreadsheets/d/1jXu52t7_5kdQY8CtEJBM8oU6PxzwQz93/edit?usp=sharing&ouid=113910437446121064118&rtpof=true&sd=true
> > > >
> > > > (inventory based on the existing inventory: https://www.web3d.org/specifications/X3dNodeInventoryComparison.xlsx
> > > >
> > > >
> > > > Vince Marchetti
> > > >
> > > >
> > > > On Feb 15, 2022, at 11:53 PM, Brutzman, Donald (Don) (CIV) <brutzman at nps.edu> wrote:
> > > >
> > > > Regular Friday meeting 08-0900 Friday, call information below.
> > > >
> > > >
> > > > Videoconference Connectivity:
> > > >
> > > > https://us02web.zoom.us/j/81634670698?pwd=a1VPeU5tN01rc21Oa3hScUlHK0Rxdz09
> > > > https://zoom.us/j/148206572 Password 483805
> > > > https://www.web3d.org/member/teleconference-information
> > > >
> > > >
> > > >
> > > > Spiraling questions about SpotLight field relationships and default values, beamwidth and cutoffAngle
> > > >
> > > >
> > > >
> > > > X3D4 Architecture, Lighting component, clause 17.4.4 SpotLight
> > > > https://www.web3d.org/specifications/X3Dv4Draft/ISO-IEC19775-1v4-CD1/Part01/components/lighting.html#SpotLight
> > > >
> > > >
> > > > excerpted
> > > >
> > > > SpotLight : X3DLightNode {
> > > >
> > > > SFFloat [in,out] beamWidth π/4 (0,π/2]
> > > >
> > > > SFFloat [in,out] cutOffAngle π/2 (0,π/2]
> > > > }
> > > >
> > > >
> > > > X3D4 Architecture, Lighting component, Figure 17.1 — SpotLight node
> > > > https://www.web3d.org/specifications/X3Dv4Draft/ISO-IEC19775-1v4-CD1/Part01/components/lighting.html#f-SpotLightnode
> > > >
> > > >
> > > >
> > > > [x3d-public] Defaults of SpotLight.cutOffAngle, beamWidth changed (maybe by mistake) in X3D 3.3
> > > > https://web3d.org/pipermail/x3d-public_web3d.org/2022-February/016744.html
> > > >
> > > >
> > > >
> > > > Mantis 441: 17.4.3 SpotLight -- Default Values (resolved 2009)
> > > > https://www.web3d.org/member-only/mantis/view.php?id=441
> > > >
> > > >
> > > > Michalis has agreed to walk us through this. Goal outcomes for confirmation:
> > > >
> > > > is figure OK?
> > > > Is relationship correct, typically beamWidth <= cutoffAngle
> > > > Should we modify default values?
> > > > Should we improve prose for clarity?
> > > >
> > > >
> > > > = = =
> > > >
> > > > Working on Mantis issues for Volume Rendering component
> > > >
> > > > https://www.web3d.org/specifications/X3Dv4Draft/ISO-IEC19775-1v4-CD1/Part01/Architecture.html
> > > >
> > > >
> > > >
> > > > X3D4 Architecture, Volume rendering component
> > > > https://www.web3d.org/specifications/X3Dv4Draft/ISO-IEC19775-1v4-CD1/Part01/Architecture.html
> > > >
> > > >
> > > > Nicholas and Michalis: please comment on following issues:
> > > >
> > > >
> > > > Mantis 917: Table 41.7 Volume rendering component support levels - ShadedVolumeStyle shadows support unclear
> > > > https://www.web3d.org/member-only/mantis/view.php?id=917
> > > >
> > > >
> > > > and
> > > >
> > > >
> > > > Mantis 709: 41.4.4 ComposedVolumeStyle - Remove reference to ordered field
> > > > https://www.web3d.org/member-only/mantis/view.php?id=709
> > > >
> > > >
> > > > Can we remove ‘ordered’ field from table?
> > > >
> > > > = = =
> > > >
> > > >
> > > > Other topics of group interest… are always welcome.
> > > >
> > > >
> > > > Membership has value! Please consider joining Web3D Consortium.
> > > >
> > > > https://www.web3D.org/join
> > > >
> > > >
> > > > Thanks for all preparations and inputs. Have fun with X3D! 8)
> > > >
> > > > all the best, Don
> > > > --
> > > > Don Brutzman Naval Postgraduate School, Code USW/Br brutzman at nps.edu
> > > > Watkins 270, MOVES Institute, Monterey CA 93943-5000 USA +1.831.656.2149
> > > > X3D graphics, virtual worlds, Navy robotics https:// faculty.nps.edu/brutzman
> > > >
> > > > _______________________________________________
> > > > x3d-public mailing list
> > > > x3d-public at web3d.org
> > > > http://web3d.org/mailman/listinfo/x3d-public_web3d.org
> > > >
> > > >
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