tag:blogger.com,1999:blog-4741970181714760187.post3591069548343754555..comments2024-03-14T19:47:05.494+00:00Comments on master maps: Converting terrain data to a WebGL-friendly formatBjørn Sandvikhttp://www.blogger.com/profile/09449118212462364491noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-4741970181714760187.post-66277556977902759562016-07-11T02:38:50.428+01:002016-07-11T02:38:50.428+01:00Thanks for this walk through the gdal tools, they’...Thanks for this walk through the gdal tools, they’re not the most accessible. Quick question — how did you figure out that “the elevation data is stored as 16-bit integers” from the gdalinfo output? Based on this line, I’d have guessed they were stored as 32-bit floating point values:<br /><br /> <i>Band 1 Block=6000x1 Type=Float32, ColorInterp=Gray</i><br /><br /><br />Honore Doktorrhttps://maps.puhonua.com/noreply@blogger.comtag:blogger.com,1999:blog-4741970181714760187.post-1115734489823611022014-10-04T17:55:32.716+01:002014-10-04T17:55:32.716+01:00I don`t understand were you get thee coordinates f...I don`t understand were you get thee coordinates for the gdalwarp.Anonymoushttps://www.blogger.com/profile/10988732982543793756noreply@blogger.comtag:blogger.com,1999:blog-4741970181714760187.post-73243456553207010212014-08-03T13:00:14.906+01:002014-08-03T13:00:14.906+01:00Ok I have managed to sort that out by using gdal_g...Ok I have managed to sort that out by using gdal_grid to make my data gridded with the following command:<br /><br />$ gdal_grid -a_srs EPSG:4326 -of GTiff -ot Float64 -outsize 1000 1000 -l all all.vrt all.tifAnonymoushttps://www.blogger.com/profile/02200276946086665774noreply@blogger.comtag:blogger.com,1999:blog-4741970181714760187.post-57800158197781656272014-07-31T16:16:45.028+01:002014-07-31T16:16:45.028+01:00Hello Bjorn,
Love your work:) everything is expla...Hello Bjorn, <br />Love your work:) everything is explained in detail and final results are always astonishing.<br /><br />I am having a problem with converting my ASCII data to binary format as you described it. I have the data in WGS 84 format:<br />50.7076,16.5009,640.00<br />50.7073,16.4998,639.73<br /><br />and I try to use gdalbuildvrt I get the following:<br />gdalbuildvrt cos.vrt M-33-45-D-d-4_p.asc<br />0...10...20...30...40...50...60...70...80...90...100 - done.<br />ERROR 1: Ungridded dataset: At line 3, X is 50.707300, where as 50.699700 was expected (1)<br />Warning 1: Can't open M-33-45-D-d-4_p.asc. Skipping it<br /><br />I tried to use gdal_grid as they suggest on their page and I have received an empty .tiff file with following stats:<br /><br />$ gdalinfo p.tiff -stats<br />Driver: GTiff/GeoTIFF<br />Files: p.tiff<br /> p.tiff.aux.xml<br />Size is 256, 256<br />Coordinate System is `'<br />Origin = (50.663200000000003,16.431699999999999)<br />Pixel Size = (0.000188671875000,0.000284765625000)<br />Image Structure Metadata:<br /> INTERLEAVE=BAND<br />Corner Coordinates:<br />Upper Left ( 50.6632000, 16.4317000) <br />Lower Left ( 50.6632000, 16.5046000) <br />Upper Right ( 50.7115000, 16.4317000) <br />Lower Right ( 50.7115000, 16.5046000) <br />Center ( 50.6873500, 16.4681500) <br />Band 1 Block=256x4 Type=Float64, ColorInterp=Gray<br /> Min=474.683 Max=1008.174 <br /> Minimum=474.683, Maximum=1008.174, Mean=720.570, StdDev=106.421<br /> Metadata:<br /> STATISTICS_MAXIMUM=1008.1740722656<br /> STATISTICS_MEAN=720.56987645384<br /> STATISTICS_MINIMUM=474.68276977539<br /> STATISTICS_STDDEV=106.42117154646<br /><br />What should I do to receive the correct tiff file (just as you did)?Anonymoushttps://www.blogger.com/profile/02200276946086665774noreply@blogger.comtag:blogger.com,1999:blog-4741970181714760187.post-55804691055822744222013-11-27T20:54:20.284+00:002013-11-27T20:54:20.284+00:00Are you familiar with any technique for smoothly t...Are you familiar with any technique for smoothly transistioning from a two dimensional view to a three dimensional view?<br /><br />Consider a 2D square for example. If I push upwards on the lower most edge of the square I would like the image to transistion into a cube. <br /><br />If there is a 2D square and a 2D rectangle on a canvas if I push upwards on the lower edge of the canvas the image transistions into a 3D cube and 3D rectangle block. <br /><br />Google Earth has this similar effect. As you fly into the map the image smoothly transistions from a 2D map image to a 3D real world terrain image just as happens in real life. Any suggestions would be welcomed. Thanks.Jaminyahhttp://jaminya.comnoreply@blogger.comtag:blogger.com,1999:blog-4741970181714760187.post-42268894316586236452013-11-08T10:03:31.885+00:002013-11-08T10:03:31.885+00:00The values are described in this blog post.The values are described in <a href="http://blog.thematicmapping.org/2012/06/digital-terrain-modeling-and-mapping.html" rel="nofollow">this blog post</a>.Bjørn Sandvikhttps://www.blogger.com/profile/16080335362672606377noreply@blogger.comtag:blogger.com,1999:blog-4741970181714760187.post-22021750354167537792013-11-08T04:49:10.799+00:002013-11-08T04:49:10.799+00:00For the gdalwarp, where do your values come from f...For the gdalwarp, where do your values come from for: 432000 6790000 492000 6850000?Anonymousnoreply@blogger.com