GiD_Raster create|interpolate
To create from the mesh a raster (2D grid) with a value that represents the z, and use a raster to efficiently interpolate values to other points or all points of other raster.
A raster is defined with a Tcl list of the following data:
<ncols> <nrows> <xllcenter> <yllcenter> <xcellsize> <ycellsize> <nodata_value> <values>
ncols, nrows are the number of columns and rows of values (representing values on center of cells)
xllcenter,yllcenter are the x,y coordinates of the lower-left corner
xcellsize, ycellsize are the x,y sizes of the cells, usually the same value (compulsory to be exported as ArcInfo grid ASCII)
<nodata_value> is the special value to represent that the data doesn't exists (usually -9999.0 for ArcInfo grid ASCII)
<values> is an objarray of (ncols x nrows) doubles with the scalar value to be represented, usually the z of the x,y node.
GiD_Raster create {nodes <xyz_nodes>} ?{<cellsize>}{<ncols> <nrows>}|{<ncols> <nrows> <xllcenter> <yllcenter> <xcellsize> <ycellsize> <nodata_value>}?
To create a raster from a cloud of 3D nodes
<xyz> must be an objarray of doubles with "x1 y1 z1 ... xn yn zn" values of a cloud of coordinates.
z data will be extrapolated to grid with and averaged value of the near nodes
...
GiD_Raster create {nodes <xyz_nodes>} {<ncols> <nrows> <xllcenter> <yllcenter> <xcellsize> <ycellsize><nodata_value>}
The raster will be created with the specified number of columns and rows, lower-left center, cell sizes and no data value.
GiD_Raster create {triangles <xyz_nodes> <elements>} ?{<cellsize>}{ncols nrows}|{ncols nrows <xllcenter> <yllcenter> <xcellsize> <ycellsize> <nodata_value>}?
To create a raster from a irregular mesh of 3D triangles
<xyz> must be an objarray of doubles with "x1 y1 z1 ... xn yn zn" values of a the node's coordinates.
<elements> must be an objarray of integers with the index (starting by 1) or the 3 nodes of each triangle. "t1_1 t1_2 t1_3 .. tn_1 tn_2 tn_3"
z data will be extrapolated to grid finding the triangle that contain the coordinate in 2D projection, or a near node.
...
GiD_Raster interpolate ?-closest? <raster_interpolation> {nodes <xy_nodes>}|{raster <raster_to_interpolate_without_data>}
To use <raster_interpolation> to calculate interpolated values of a collection of 2D nodes or all grid nodes of another raster
It returns and obj_array of doubles with the interpolated value for each node
<xy_nodes> list of x y coordinates "x1 y1 ... xn yn" of the points to interpolate the value
<raster_to_interpolate_without_data> another raster (its values could be a emtpy objarray)
If -closest flag is set, then instead interpolate it get the value of the closest grid node (interesting to map non-continous integer values)
...