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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>OK. Let’s say you want to define a physics component. What would be on your wish list for its content?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Roy<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> x3d-public [mailto:x3d-public-bounces@web3d.org] <b>On Behalf Of </b>Tony Parisi<br><b>Sent:</b> 25 April 2015 00:09<br><b>To:</b> Dave A<br><b>Cc:</b> x3d-public@3dnpvei.com; x3d-public@web3d.org<br><b>Subject:</b> Re: [x3d-public] Gravity Sensor?<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal style='margin-bottom:12.0pt'>Another option is to define a physics component and do it everything consistently through that component... maybe borrow some features of the physics model in the ParticleSystem component since that's out there already...<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On Fri, Apr 24, 2015 at 4:01 PM, Dave A <<a href="mailto:dave@realmofconcepts.com" target="_blank">dave@realmofconcepts.com</a>> wrote:<o:p></o:p></p><p class=MsoNormal>This has been a bother for me since I got into x3d in 2003.<br><br>Follow me! @thatvrguy<o:p></o:p></p><div><div><p class=MsoNormal><br><br>On 4/24/2015 2:57 PM, Christoph Valentin wrote:<o:p></o:p></p><p class=MsoNormal>Hi Dave,<br> I believe, X3DOM has done that and I believe a lot of open and/or closed source game engines have done that. No doubt.<br> The point is, to have it in an ISO standard on a high layer of scene description (i.e. X3D/VRML).<br> All the best<br> <br>Gesendet: Freitag, 24. April 2015 um 19:18 Uhr<br>Von: "Dave A" <<a href="mailto:dave@realmofconcepts.com" target="_blank">dave@realmofconcepts.com</a>><br>An: "Christoph Valentin" <<a href="mailto:christoph.valentin@gmx.at" target="_blank">christoph.valentin@gmx.at</a>>, <a href="mailto:x3d-public@3dnpvei.com" target="_blank">x3d-public@3dnpvei.com</a>, "Roy Walmsley" <<a href="mailto:roy.walmsley@ntlworld.com" target="_blank">roy.walmsley@ntlworld.com</a>><br>Cc: <a href="mailto:x3d-public@web3d.org" target="_blank">x3d-public@web3d.org</a><br>Betreff: Re: [x3d-public] Gravity Sensor?<br>I think what you are asking for is a Physics Engine. Has one been<br>integrated yet? It really needs it.<br>I think x3dom glued one in somehow.<br>Dave Arendash<br><br>On 4/24/2015 7:16 AM, Christoph Valentin wrote:<o:p></o:p></p><p class=MsoNormal>Thanks Lauren and Roy,<br><br>My question was from a theoretical perspective (maybe I will do some trials with GeoSpatial component soon).<br><br>Thinking about railway cars, that contain scenery and avatar can enter. --> need superposition of gravity and inertial forces (from the acceleration of the railway car).<br><br>KR<br><br><br><br>Gesendet: Freitag, 24. April 2015 um 14:12 Uhr<br>Von: GLG <<a href="mailto:x3d-public@3dnpvei.com" target="_blank">x3d-public@3dnpvei.com</a>><br>An: <a href="mailto:x3d-public@web3d.org" target="_blank">x3d-public@web3d.org</a><br>Betreff: Re: [x3d-public] Gravity Sensor?<br>Yes there's ParticleSystems (thanks Roy), maybe the<br>X3DParticlePhysicsModelNode in particular is what you're looking for, or the<br>X3DParticlePhysicsModelNode. Cheers, Lauren<br><br><br>40.4.4 ForcePhysicsModel<br><br>GravityPhysicsModel : X3DParticlePhysicsModelNode {<br>SFBool [in,out] enabled TRUE<br>SFVec3f [in,out] force 0 -9.8 0 (∞,∞)<br>SFNode [in,out] metadata NULL [X3DMetadataObject]<br>}<br>The ForcePhysicsModel node specifies a physics model that applies a constant<br>force value to the particles. Force may act in any given direction vector at<br>any strength.<br><br>The force field is used to indicate the strength and direction of the force<br>(e.g., gravity) that should be applied. Force is specified in metres per<br>seconds-squared (m/s2). If the particles are defined to have zero mass by<br>the emitter, the ForcePhysicsModel node has no effect.<br><br><br>40.4.1 BoundedPhysicsModel<br><br>BoundedPhysicsModel : X3DParticlePhysicsModelNode {<br>SFBool [in,out] enabled TRUE<br>SFNode [in,out] geometry NULL [X3DGeometryNode]<br>SFNode [in,out] metadata NULL [X3DMetadataObject]<br>}<br>The BoundedPhysicsModel node specifies a physics model that applies a<br>user-defined set of geometrical bounds to the particles.<br><br>The geometry field specifies a piece of geometry that models the bounds that<br>constrain the location of the particles. When a particle touches the surface<br>of the bounds, it is reflected. The particles may be restricted to an inside<br>location or an outside location. All geometry defined by the bounds are<br>considered to be non-solid, regardless of the setting of the solid field. It<br>does not matter whether the particle impacts the front or back side of the<br>geometry. Particles are reflected at the same angle to the normal of the<br>surface to which they impact, continuing in the same direction. The<br>calculation of the correct normal is determined by the rules of the geometry<br>that forms the bounds.<br><br>EXAMPLE A particle can be made to bounce off an elevation grid representing<br>terrain.<br><br><br><a href="http://www.web3d.org/documents/specifications/19775-1/V3.2/Part01/components" target="_blank">http://www.web3d.org/documents/specifications/19775-1/V3.2/Part01/components</a><br>/particle_systems.html<br><br><br><br><br>-----Original Message-----<br>From: x3d-public [mailto:<a href="mailto:x3d-public-bounces@web3d.org" target="_blank">x3d-public-bounces@web3d.org</a>] On Behalf Of Roy<br>Walmsley<br>Sent: Friday, April 24, 2015 5:31 AM<br>To: 'Christoph Valentin'; 'X3D Graphics public mailing list'<br>Subject: Re: [x3d-public] Gravity Sensor?<br><br>Christoph,<br><br>In X3D the only place where forces, including gravity, can be included is in<br>the Particle systems component.<br><br>There isn't anything like a "gravity sensor". You have to take care of it<br>yourself. This could be done using external code and interacting through the<br>SAI. Alternatively, you could use a Script node to keep everything internal<br>to the scene.<br><br>>From your reasoning point d) I am assuming you are working with the<br>GeoSpatial component. What sort of things do you want to apply gravity to?<br><br>Roy<br><br>-----Original Message-----<br>From: x3d-public [mailto:<a href="mailto:x3d-public-bounces@web3d.org" target="_blank">x3d-public-bounces@web3d.org</a>] On Behalf Of<br>Christoph Valentin<br>Sent: 24 April 2015 10:04<br>To: X3D Graphics public mailing list<br>Subject: [x3d-public] Gravity Sensor?<br><br>A few questions to the community.<br><br>Is there something like a "gravity sensor" in X3D/VRML?<br><br>Reasoning:<br><br>a) The Web3D Browser cares for gravity and collision detection, when<br>controlling the movement of the avatar.<br>b) However, when controlling the dynamics of an arbitrary object, I have to<br>care for gravity and collision myself<br>c) In classical scenes, the gravity is 9.81 m.s^-2 in -y direction, no<br>problem<br>d) But how to calculate gravity in an X3D-Earth scene? Don't we need a kind<br>of "gravity sensor" here?<br><br>_______________________________________________<br>x3d-public mailing list<br><a href="mailto:x3d-public@web3d.org" target="_blank">x3d-public@web3d.org</a><br><a href="http://web3d.org/mailman/listinfo/x3d-public_web3d.org%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5D%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5D%5D" target="_blank">http://web3d.org/mailman/listinfo/x3d-public_web3d.org[http://web3d.org/mailman/listinfo/x3d-public_web3d.org][http://web3d.org/mailman/listinfo/x3d-public_web3d.org[http://web3d.org/mailman/listinfo/x3d-public_web3d.org]]</a><br><br><br><br>_______________________________________________<br>x3d-public mailing list<br><a href="mailto:x3d-public@web3d.org" target="_blank">x3d-public@web3d.org</a><br><a href="http://web3d.org/mailman/listinfo/x3d-public_web3d.org%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5D%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5D%5D" target="_blank">http://web3d.org/mailman/listinfo/x3d-public_web3d.org[http://web3d.org/mailman/listinfo/x3d-public_web3d.org][http://web3d.org/mailman/listinfo/x3d-public_web3d.org[http://web3d.org/mailman/listinfo/x3d-public_web3d.org]]</a><br><br><br>_______________________________________________<br>x3d-public mailing list<br><a href="mailto:x3d-public@web3d.org" target="_blank">x3d-public@web3d.org</a><br><a href="http://web3d.org/mailman/listinfo/x3d-public_web3d.org%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5D%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5D%5D" target="_blank">http://web3d.org/mailman/listinfo/x3d-public_web3d.org[http://web3d.org/mailman/listinfo/x3d-public_web3d.org][http://web3d.org/mailman/listinfo/x3d-public_web3d.org[http://web3d.org/mailman/listinfo/x3d-public_web3d.org]]</a><br><br>_______________________________________________<br>x3d-public mailing list<br><a href="mailto:x3d-public@web3d.org" target="_blank">x3d-public@web3d.org</a><br><a href="http://web3d.org/mailman/listinfo/x3d-public_web3d.org%5Bhttp:/web3d.org/mailman/listinfo/x3d-public_web3d.org%5D" target="_blank">http://web3d.org/mailman/listinfo/x3d-public_web3d.org[http://web3d.org/mailman/listinfo/x3d-public_web3d.org]</a><br><br><br>-----<br>No virus found in this message.<br>Checked by AVG - <a href="http://www.avg.com" target="_blank">www.avg.com</a>[<a href="http://www.avg.com" target="_blank">http://www.avg.com</a>]<br>Version: 2015.0.5863 / Virus Database: 4334/9610 - Release Date: 04/24/15<o:p></o:p></p><p class=MsoNormal>--<br>Follow me! @thatvrguy<br> <o:p></o:p></p><p class=MsoNormal><br><br>_______________________________________________<br>x3d-public mailing list<br><a href="mailto:x3d-public@web3d.org" target="_blank">x3d-public@web3d.org</a><br><a href="http://web3d.org/mailman/listinfo/x3d-public_web3d.org" target="_blank">http://web3d.org/mailman/listinfo/x3d-public_web3d.org</a><o:p></o:p></p></div></div></div><p class=MsoNormal><br><br clear=all><br>-- <o:p></o:p></p><div><div><div><div><div><div><div><div><div><p class=MsoNormal><br><br>Tony Parisi <a href="mailto:tparisi@gmail.com" target="_blank">tparisi@gmail.com</a><o:p></o:p></p></div><div><p class=MsoNormal>Founder, Third Eye <a href="http://www.thirdeye.gl/" target="_blank">http://www.thirdeye.gl/</a><o:p></o:p></p></div><p class=MsoNormal>Follow me on Twitter! <a href="http://twitter.com/auradeluxe" target="_blank">http://twitter.com/auradeluxe</a><o:p></o:p></p><div><p class=MsoNormal>Read my blog at <a href="http://www.tonyparisi.com/" target="_blank">http://www.tonyparisi.com/</a><o:p></o:p></p></div><p class=MsoNormal>Learn WebGL <a href="http://learningwebgl.com/" target="_blank">http://learningwebgl.com/</a><o:p></o:p></p><div><div><p class=MsoNormal>Mobile 415.902.8002<o:p></o:p></p></div><div><p class=MsoNormal>Skype auradeluxe<o:p></o:p></p></div><p class=MsoNormal style='margin-bottom:12.0pt'><br>Read my books! <i><br>Programming 3D Applications in HTML5 and WebGL<br><a href="http://www.amazon.com/Programming-Applications-HTML5-WebGL-Visualization/dp/1449362966" target="_blank">http://www.amazon.com/Programming-Applications-HTML5-WebGL-Visualization/dp/1449362966</a><br>WebGL, Up and Running</i><br><a href="http://www.amazon.com/dp/144932357X" target="_blank">http://www.amazon.com/dp/144932357X</a><o:p></o:p></p></div></div></div></div></div></div></div></div></div></div></div></body></html>