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]   [fs=string]   [v=integer]   [--verbose]  [--quiet]

   Flags:
       -g
           Produces shell script output

       -w
           Produces web map server query string output

       --verbose
           Verbose module output

       --quiet
           Quiet module output

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

       sourceproj=string
           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

       fs=string
           Output field separator
           Default: |

       v=integer
           Verbosity level
           Default: 0

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 convinent for setting variables in a shell script.

       bbox=5,125,45,175&width=80&height=100
              This is output in a format convinent 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

BUGS

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

AUTHORS

       Cedric Shock
       Update by Martin Landa, CTU in Prague, Czech Republic

       Last changed: $Date: 2012-12-14 05:07:10 -0800 (Fri, 14 Dec 2012) $

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