NAME

       r.tileset  - Produces tilings of the source projection for use in the destination region and projection.

KEYWORDS

       raster, tiling

SYNOPSIS

       r.tileset
       r.tileset --help
       r.tileset    [-gw]     [region=string]    sourceproj=string    [sourcescale=string]     [destproj=string]
       [destscale=string]   [maxcols=integer]    [maxrows=integer]    [overlap=integer]    [separator=character]
       [--help]  [--verbose]  [--quiet]  [--ui]

   Flags:
       -g
           Produces shell script output

       -w
           Produces web map server query string output

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       region=string
           Name of region to use instead of current region for bounds and resolution

       sourceproj=string [required]
           Source projection

       sourcescale=string
           Conversion factor from units to meters in source projection
           Default: 1

       destproj=string
           Destination projection, defaults to this location’s projection

       destscale=string
           Conversion factor from units to meters in source projection

       maxcols=integer
           Maximum number of columns for a tile in the source projection
           Default: 1024

       maxrows=integer
           Maximum number of rows for a tile in the source projection
           Default: 1024

       overlap=integer
           Number of cells tiles should overlap in each direction
           Default: 0

       separator=character
           Field separator
           Output field separator
           Default: pipe

DESCRIPTION

       r.tileset  generates  sets  of  tiles  in  another projection that cover a region in this projection with
       adequate resolution. By default the current region and its resolution are used, the bounds and resolution
       of another region can be used via the region option.

NOTES

       r.tileset does not make "optimal" tilings (as few tiles of the largest size less than the maximums). This
       means that from latitude longitude  projection  to  an  appropriate  projection  for  a  region,  in  the
       degenerate  case,  it  may  create  tiles  demanding  up to twice the necessary information. Furthermore,
       generating a tiling near a divergant point of a source projection, such as the  poles  of  a  cylindrical
       source projections, results in divergence of the tile set.

       Not  generating  "optimal"  tilings  may  have  another  consequence;  the  aspect  ratio of cells in the
       destination region will not necessarily carry over to the source region  and  generated  tiles  may  have
       cells  of strange aspect ratios. This might be a problem for some map request services presenting data in
       an inappropriate projection or with strict constraints on cell aspect ratio.

OUTPUT FORMAT

       Each tile is listed on a separate line in the output. The lines are formatted as follows:

         5|125|45|175|80|100
           This is the default output format. It is the tile’s  minimum  x  coordinate,  minimum  y  coordinate,
           maximum  x coordinate, maximum y coordinate, width in cells, and height in cells separated by the "|"
           character. The fields can be separated by a different character by changing the fs option.

         w=5;s=125;e=45;n=175;cols=80;rows=100;
           This is output in a format convenient for setting variables in a shell script.

         bbox=5,125,45,175&width=80&height=100
           This is output in a format convenient for requesting data from some http services.

EXAMPLES

       Generates tiles in latitude longitude that cover the current region, each tile will  be  less  than  1024
       cells high and 2048 cells across. The bounds and sizes of tiles in the output are separated by | (pipe):

       r.tileset sourceproj=+init=epsg:4326 maxrows=1024 maxcols=2048
       Generates  tiles  in  latitude  longitude projection that cover the named region "ne-rio". The tiles will
       have 2 cells of overlap. The output format will be strings like the bbox requests for WMS servers:

       r.tileset sourceproj=+init=epsg:4326 overlap=2 -w region=ne-rio
       Generates tiles in the projection of the location "IrishGrid". Each tile will be less than 300x400  cells
       in size, with 3 cells of overlap in the top and right sides of each tile. The output is in a format where
       each line is in shell script style. The substitution `g.proj -j location=IrishGrid` will only work  in  a
       unix style shell:

       r.tileset sourceproj="`g.proj -j location=IrishGrid`" maxrows=400 maxcols=300 overlap=3 -g

KNOWN ISSUES

           •   r.tileset does not know about meridians that "wrap-around" in projections.

AUTHORS

       Cedric Shock
       Updated for GRASS 7 by Martin Landa, CTU in Prague, Czech Republic

SOURCE CODE

       Available at: r.tileset source code (history)

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       © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual