[GRASS5] Grass 5.1

[Radim Blazek]

Hi,

I have commited few changes to grass51:

1) Make
I have merged and modified 
grass50/configure + grass51/notyetuploaded/new_makefile_system
Make system is not my hobby but it was impossible to compile grass51
in the new dir structure with old gmake system. Anybody can modify
and improve or completely rewrite that.

2) Debug
New function G_debug (int  level, char * msg) prints message if enviroment 
variable GRASS_DEBUG_LEVEL is set to level equal or higher.
My proposal for levels is:
 * Levels: (recommended levels)
 * 1 - messages printed once or few times per module
 * 3 - each row (raster) or line (vector)
 * 5 - each cell (raster) or point (vector)
and I use optional compilation (speed): 
#ifdef GDEBUG
      G_debug (1, "Vect_open_old(): name = %s mapset= %s", name, mapset);
#endif

3) Multiformat vector
I have built into vector library frame for multiformat support. At present we 
have:
* native - read/write on level1
* shape - reads geometry of all types (point, line, polygon), for polygons
                  I want add some pseudo topological access i.e. areas can be 
                  read, but correct topology is no available
* postGIS - written is only small test (read/write line geometry).  
                  On  PostGIS interface will work group of students 
                   on "University of Sannio" lead by   Professor Giuliano     
                   Antoniol. They should start next week.

Non-native sources are defined in frmt file in vector dir, example:
FORMAT: shape
SHAPE: /home/radim/gdata/g4t/cmd/shpout/river
CAT_COLUMN: id
or:
FORMAT: postgis
DATABASE: pgis
GEOM_TABLE: t1
GEOM_GEOM: the_geom

First benchmark (native x postGIS)
50 lines (each 100 points) 
Action          native     postGis
import            1                 26
display          1                 1
export            1                 3
But !!! everything is done through text strings, it will be better in final 
version.

4) Plans
During next days I want to modify native vector format according to 
discussion in Trento (type as byte, shorter header) and then look at topo 
file and try to update topology support for g51 and clean bit lib/diglib/ 
dir. 



I think that we should open new mailing list for grass51 development
and possibly close some mailing lists with low traffic:
- Grass GUI (last message Mon, 5 Nov 2001 about gdal installation !!!)
- SQL Grass (19 messages October-December)
- NVIZ (no message abou nviz in archive)

Radim