The GUI (Graphical User Interface) is written in the Python programming language using wxPython library - a blending of the wxWidgets library for Python.

The wxPython GUI (so called wxGUI) is composed of two main components:

Layer Manager and
Map Display Window.

The Layer Manager allows users to run different GRASS modules from a menu, includes map layer management, integrated command-line prompt, and command output window. The Map Display Window integrates basic tools for zooming, panning, data querying, decorations (north arrows, barscale, etc.). Additional tools like vector digitizer or georectification tool are also available.

Table of content

Background

The plan for a native GUI for GRASS found its origin in the project GFOSS-TN, a collaboration between FBK (Fondazione Bruno Kessler) and the Information System Service of the Trento municipality (Italy). The wxGUI is successor of Tcl/Tk GUI available in GRASS 5 and GRASS 6.

List of Modules and Classes

Core modules

GUI core modules

gui_core::dialogs
- dialogs::ElementDialog
- dialogs::LocationDialog
- dialogs::MapsetDialog
- dialogs::NewVectorDialog
- dialogs::SavedRegion
- dialogs::DecorationDialog
- dialogs::TextLayerDialog
- dialogs::GroupDialog
- dialogs::MapLayersDialog
- dialogs::ImportDialog
- dialogs::GdalImportDialog
- dialogs::GdalOutputDialog
- dialogs::DxfImportDialog
- dialogs::LayersList (used by MultiImport)
- dialogs::SetOpacityDialog
- dialogs::StaticWrapText
- dialogs::ImageSizeDialog
- dialogs::SqlQueryFrame
gui_core::forms
gui_core::ghelp
gui_core::goutput
gui_core::gselect
- gselect::Select
- gselect::VectorSelect
- gselect::TreeCrtlComboPopup
- gselect::VectorDBInfo
- gselect::LayerSelect
- gselect::DriverSelect
- gselect::DatabaseSelect
- gselect::ColumnSelect
- gselect::DbaseSelect
- gselect::LocationSelect
- gselect::MapsetSelect
- gselect::SubGroupSelect
- gselect::FormatSelect
- gselect::GdalSelect
- gselect::ProjSelect
- gselect::ElementSelect
- gselect::OgrTypeSelect
gui_core::mapdisp
- mapdisp::MapFrameBase
gui_core::mapwindow
- mapwindow::MapWindow
gui_core::menu
gui_core::preferences
gui_core::prompt
gui_core::toolbars
- toolbars::BaseToolbar
gui_core::widgets

Layer Manager

wxgui
- wxgui::GMFrame
- wxgui::GMApp
- wxgui::Usage
lmgr::layertree
- lmgr::LayerTree
lmgr::menudata
- menudata::MenuData
lmgr::pyshell
- pyshell::PyShellWindow
lmgr::toolbars

Map Display Window

Welcome screen

gis_set_error
gis_set

Database Manager

Georectifier

gcp::manager
gcp::mapdisplay
mapdisplay::MapFrame
gcp::toolbars
- toolbars::GCPMapToolbar
- toolbars::GCPDisplayToolbar

Graphical Modeler

Vector digitizer

3D view mode (wxNviz)

Cartograpic Composer

psmap::dialogs
psmap::instructions
- dialogs::Instruction
- dialogs::InstructionObject
- dialogs::InitMap
- dialogs::MapFrame
- dialogs::PageSetup
- dialogs::Mapinfo
- dialogs::Text
- dialogs::Image
- dialogs::NorthArrow
- dialogs::Point
- dialogs::Line
- dialogs::Rectangle
- dialogs::Scalebar
- dialogs::RasterLegend
- dialogs::VectorLegend
- dialogs::Raster
- dialogs::Vector
- dialogs::VProperties
psmap::utils
psmap::frame
- frame::PsMapFrame
- frame::PsMapBufferedWindow
psmap::menudata
- menudata::PsMapData
psmap::toolbars
- toolbars::PsMapToolbar

Location Wizard

Plotting modules

wxplot::base
- base::BasePlotFrame
wxplot::dialogs
- dialogs::ProfileRasterDialog
- dialogs::ScatterRasterDialog
- dialogs::PlotStatsFrame
- dialogs::HistRasterDialog
- dialogs::TextDialog
- dialogs::OptDialog
wxplot::histogram
- histogram::Histogram2Frame
- histogram::Histogram2Toolbar
wxplot::profile
- profile::ProfileFrame
- profile::ProfileToolbar
wxplot::scatter
- scatter::ScatterFrame
- scatter::ScatterToolbar

Other GUI modules

modules::colorrules
- colorrules::RulesPanel
- colorrules::ColorTable
- colorrules::RasterColorTable
- colorrules::VectorColorTable
- colorrules::ThematicVectorTable
- colorrules::BufferedWindow
modules::extensions
modules::histogram
modules::mcalc_builder
- mcalc_builder::MapCalcFrame
modules::ogc_services
- ogc_services::WMSDialog
- ogc_services::LayersList
modules::vclean
- vclean::VectorCleaningFrame

Further Development

Ongoing development focuses on stability, portability and on the integration of OpenGL (see 3D view mode (wxNviz)).

A Map Composer, a tool for hardcopy map outputs is also planned to be developed. Currently, the tools for creating hardcopy maps (map layout) are limited in GRASS because its focus on modeling and spatial analysis. GRASS gives the user ability to add only a very simple and standardized legend, north arrow and scale to display to the graphics monitor and then export the display to an external image file such as a png. These map features are very basic and cannot be customized. The goal is to allow users to prepare simple cartographic outputs comparable e.g. with other, proprietary GIS map layout functionality.

For more info see http://trac.osgeo.org/grass/wiki/wxGUIDevelopment

References

M. Landa, C. Moretto, M. Neteler, M. Zanolli, L. Manganelli, 2008: wxPython GUI per GRASS GIS. Proc. IX Meeting degli Utenti Italiani di GRASS - GFOSS - 21-22 Feb 2008, Perugia, Italy (PDF)