Re: [osg-users] Paging strategies for road tiles
Björn Blissing wrote on Thursday, August 27, 2009 2:32 AM: > Hi Brian, > > Yes, my tiles are a lot larger than 2000 meter. The radius of the first tile > is 9008.5 m, and the road segment contained in that segment is 18017 m. But > should really the range value be connected to the tile size?? I my mind it > should work in the way that if my eye point comes within the specified range > the LOD tile should appear. And by "within range" I mean that distance from > the eye point to the edge of the bounding sphere of the tile. But maybe I > have completely missunderstood the concept here?? The LOD radius is tested using the distance from the eye point to the center of the LOD (which defaults to the center of the bounding sphere), so if you want them to appear 2000 meters before the edge of the bounding sphere, you need to set the LOD radius to 2000+bounding sphere radius. > Hi Bjorn, > > It looks like the problem is your tiles are larger than 2000 m radius. > > Try setting the range to the tile radius, or some multiple (1.5 * radius, > 2.0 * radius). > > Brian > > This is a PRIVATE message. If you are not the intended recipient, please > delete without copying and kindly advise us by e-mail of the mistake in > delivery. > NOTE: Regardless of content, this e-mail shall not operate to bind CSC to > any order or other contract unless pursuant to explicit written agreement > or government initiative expressly permitting the use of e-mail for such > purpose. * > -osg-users-boun...@lists.openscenegraph.org wrote: - > > To: "OpenSceneGraph Users" > From: Björn Blissing > Sent by: osg-users-boun...@lists.openscenegraph.org > Date: 08/26/2009 11:56AM > Subject: [osg-users] Paging strategies for road tiles > > Hi all, > > My application involves road vehicles driving down long roads. Approx 1000 > km of continuous road. The problem is that I can only hold about 100 km of > road before system memory runs out. Plan B then naturally falls on some > sort of paging strategy. I rewrote the software so it generates .ive files > containing about 10-30 km road. Then the plan was to use pagedLOD to page > in the files when needed. > > My test program only uses four of these tiles, but I do not seem to get it > right. My pagedLOD nodes all lie under the scene graph root. Each one only > contains a reference to the corresponding .ive file and a range set from 0 > to 2000 (since I don't want the next geometry to be paged in until I am > closer than 2000 meters). The center of each pagedLOD node is set to the > center point of the geometry in the file and the radius is set to half the > length of the road in the file. > > But no geometry is ever paged in. > > If I set the center to (0, 0, 0) the geometry will page in the first > segment of road, but then the geometry disappears when I traveled more than > 2000 meters. The other tiles never shows up. > > I am obviously missing something when setting up my pagedLOD. If someone > could give me a hint I would be most thankful. -- Bryan Thrall FlightSafety International bryan.thr...@flightsafety.com ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Paging strategies for road tiles
Hi Brian, Yes, my tiles are a lot larger than 2000 meter. The radius of the first tile is 9008.5 m, and the road segment contained in that segment is 18017 m. But should really the range value be connected to the tile size?? I my mind it should work in the way that if my eye point comes within the specified range the LOD tile should appear. And by "within range" I mean that distance from the eye point to the edge of the bounding sphere of the tile. But maybe I have completely missunderstood the concept here?? Best regards, Björn Hi Bjorn, It looks like the problem is your tiles are larger than 2000 m radius. Try setting the range to the tile radius, or some multiple (1.5 * radius, 2.0 * radius). Brian This is a PRIVATE message. If you are not the intended recipient, please delete without copying and kindly advise us by e-mail of the mistake in delivery. NOTE: Regardless of content, this e-mail shall not operate to bind CSC to any order or other contract unless pursuant to explicit written agreement or government initiative expressly permitting the use of e-mail for such purpose. * -osg-users-boun...@lists.openscenegraph.org wrote: - To: "OpenSceneGraph Users" From: Björn Blissing Sent by: osg-users-boun...@lists.openscenegraph.org Date: 08/26/2009 11:56AM Subject: [osg-users] Paging strategies for road tiles Hi all, My application involves road vehicles driving down long roads. Approx 1000 km of continuous road. The problem is that I can only hold about 100 km of road before system memory runs out. Plan B then naturally falls on some sort of paging strategy. I rewrote the software so it generates .ive files containing about 10-30 km road. Then the plan was to use pagedLOD to page in the files when needed. My test program only uses four of these tiles, but I do not seem to get it right. My pagedLOD nodes all lie under the scene graph root. Each one only contains a reference to the corresponding .ive file and a range set from 0 to 2000 (since I don't want the next geometry to be paged in until I am closer than 2000 meters). The center of each pagedLOD node is set to the center point of the geometry in the file and the radius is set to half the length of the road in the file. But no geometry is ever paged in. If I set the center to (0, 0, 0) the geometry will page in the first segment of road, but then the geometry disappears when I traveled more than 2000 meters. The other tiles never shows up. I am obviously missing something when setting up my pagedLOD. If someone could give me a hint I would be most thankful. Best Regards, Björn If I output my scenegraph to a osg-file this is the content: Group { nodeMask 0x cullingActive TRUE num_children 4 PagedLOD { nodeMask 0x cullingActive TRUE Center 8933.58 -982.774 0 Radius 9008.5 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile1.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 19930.8 8704.41 0 Radius 6001 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile2.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 34616.1 17445.3 0 Radius 11875 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile3.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 47754.4 25857.3 0 Radius 3955 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile4.ive } num_children 0 } } ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Paging strategies for road tiles
Hi Bjorn, It looks like the problem is your tiles are larger than 2000 m radius. Try setting the range to the tile radius, or some multiple (1.5 * radius, 2.0 * radius). Brian This is a PRIVATE message. If you are not the intended recipient, please delete without copying and kindly advise us by e-mail of the mistake in delivery. NOTE: Regardless of content, this e-mail shall not operate to bind CSC to any order or other contract unless pursuant to explicit written agreement or government initiative expressly permitting the use of e-mail for such purpose. • -osg-users-boun...@lists.openscenegraph.org wrote: - To: "OpenSceneGraph Users" From: Björn Blissing Sent by: osg-users-boun...@lists.openscenegraph.org Date: 08/26/2009 11:56AM Subject: [osg-users] Paging strategies for road tiles Hi all, My application involves road vehicles driving down long roads. Approx 1000 km of continuous road. The problem is that I can only hold about 100 km of road before system memory runs out. Plan B then naturally falls on some sort of paging strategy. I rewrote the software so it generates .ive files containing about 10-30 km road. Then the plan was to use pagedLOD to page in the files when needed. My test program only uses four of these tiles, but I do not seem to get it right. My pagedLOD nodes all lie under the scene graph root. Each one only contains a reference to the corresponding .ive file and a range set from 0 to 2000 (since I don't want the next geometry to be paged in until I am closer than 2000 meters). The center of each pagedLOD node is set to the center point of the geometry in the file and the radius is set to half the length of the road in the file. But no geometry is ever paged in. If I set the center to (0, 0, 0) the geometry will page in the first segment of road, but then the geometry disappears when I traveled more than 2000 meters. The other tiles never shows up. I am obviously missing something when setting up my pagedLOD. If someone could give me a hint I would be most thankful. Best Regards, Björn If I output my scenegraph to a osg-file this is the content: Group { nodeMask 0x cullingActive TRUE num_children 4 PagedLOD { nodeMask 0x cullingActive TRUE Center 8933.58 -982.774 0 Radius 9008.5 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile1.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 19930.8 8704.41 0 Radius 6001 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile2.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 34616.1 17445.3 0 Radius 11875 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile3.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 47754.4 25857.3 0 Radius 3955 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile4.ive } num_children 0 } } ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] Paging strategies for road tiles
Hi all, My application involves road vehicles driving down long roads. Approx 1000 km of continuous road. The problem is that I can only hold about 100 km of road before system memory runs out. Plan B then naturally falls on some sort of paging strategy. I rewrote the software so it generates .ive files containing about 10-30 km road. Then the plan was to use pagedLOD to page in the files when needed. My test program only uses four of these tiles, but I do not seem to get it right. My pagedLOD nodes all lie under the scene graph root. Each one only contains a reference to the corresponding .ive file and a range set from 0 to 2000 (since I don't want the next geometry to be paged in until I am closer than 2000 meters). The center of each pagedLOD node is set to the center point of the geometry in the file and the radius is set to half the length of the road in the file. But no geometry is ever paged in. If I set the center to (0, 0, 0) the geometry will page in the first segment of road, but then the geometry disappears when I traveled more than 2000 meters. The other tiles never shows up. I am obviously missing something when setting up my pagedLOD. If someone could give me a hint I would be most thankful. Best Regards, Björn If I output my scenegraph to a osg-file this is the content: Group { nodeMask 0x cullingActive TRUE num_children 4 PagedLOD { nodeMask 0x cullingActive TRUE Center 8933.58 -982.774 0 Radius 9008.5 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile1.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 19930.8 8704.41 0 Radius 6001 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile2.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 34616.1 17445.3 0 Radius 11875 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile3.ive } num_children 0 } PagedLOD { nodeMask 0x cullingActive TRUE Center 47754.4 25857.3 0 Radius 3955 RangeMode DISTANCE_FROM_EYE_POINT RangeList 1 { 0 2000 } NumChildrenThatCannotBeExpired 0 FileNameList 1 { c://tile4.ive } num_children 0 } } ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org