1r.li.daemon(1) GRASS GIS User's Manual r.li.daemon(1)
2
7 This documentation is focused on scientists and developers who wants to
8 implement a new landscape index computation. Refer to the r.li modules
9 overview and g.gui.rlisetup module for user-focused documentation.
10 r.li.daemon provides support for landscape index calculations on raster
12 maps. It hides the management of areas, defined using g.gui.rlisetup
13 command. It is not used like a standalone program, but its functions
14 are a library used by all r.li.[index] commands.
15 This description is a tutorial for new index definition.
16 The developer has only to focus on a unique area, like in mathematical
17 definitions, and has to write a C implementation of it.
18 The areas are defined using a struct called area_des and it members are
19 explained in the source code (doxygen) documentation.
20 To write a new index only two steps are needed:
22 1 Define a function and insert its declaration on file index.h in
24 r.li.daemon folder, which contains all index declarations. This
25 function must be of this kind:
26 int index(int fd, char ** par, area_des ad, double * result)
27 where:
28 · fd is the raster map descriptor
30 · par is a matrix for special parameter (like argv in main)
32 · ad is the area descriptor
34 · result is where to put the index calculation result
36 This function has to return 1 on success and 0 otherwise. This func‐
37 tion type is defined using typedef named rli_func.
38 2 Create a main for command line arguments parsing, and call the
40 function
41 int calculateIndex(char *file, rli_func *f,
42 char **parameters, char *raster, char *output);
43 from the r.li library, for starting raster analysis.
44 It follows the meaning of parameters:
45 · file name of configuration file created using g.gui.rlisetup
47 · f pointer to index function defined above
49 · parameters pointer to index special parameters
51 · raster name of raster to use
53 · output output file name
55 Compile it using a changed Makefile based on the file for r.li.patch‐
57 density.
58 Refer to the r.li library documentation in the source code and imple‐
60 mentation of r.li modules for details and examples.
61
63 Using GRASS library function to access raster rows can slow down moving
64 windows execution. It is recommended to use
65 RLI_get_cell_row(int, int, area_des)
66 RLI_get_fcell_row(int, int, area_des)
67 RLI_get_dcell_row(int, int, area_des)
68 to use an ad hoc build memory management developed to speed up the sys‐
69 tem. The documentation is in doxygen files.
70
72 old r.le manual
73 r.li - package overview
74 g.gui.rlisetup
75
77 McGarigal, K., and B. J. Marks. 1995. FRAGSTATS: spatial pattern analy‐
78 sis program for quantifying landscape structure. USDA For. Serv. Gen.
79 Tech. Rep. PNW-351. (PDF)
80
82 Claudio Porta and Lucio Davide Spano, students of Computer Science Uni‐
83 versity of Pisa (Italy).
84 Commission from Faunalia Pontedera (PI)
85 Rewritten from "r.le.setup" by William L. Baker
86 Various bug fixes by Markus Metz
87 This program is free software under the GPL (>=v2) Read the COPYING
88 file that comes with GRASS for details.
89 Main index | Topics index | Keywords index | Graphical index | Full
91 index
92 © 2003-2020 GRASS Development Team, GRASS GIS 7.8.5 Reference Manual
94GRASS 7.8.5 r.li.daemon(1)