Geografic-Information-System/gui/wxpython/core/render.py

"""
@package core.render

@brief Rendering map layers and overlays into map composition image.

.. todo::
    Implement RenderManager also for other layers (see WMS
    implementation for details)

.. todo::
    Render classes should not care about updating statusbar (change
    emiting events).

Classes:
 - render::Layer
 - render::MapLayer
 - render::Overlay
 - render::Map

(C) 2006-2013 by the GRASS Development Team

This program is free software under the GNU General Public License
(>=v2). Read the file COPYING that comes with GRASS for details.

@author Michael Barton
@author Jachym Cepicky
@author Martin Landa <landa.martin gmail.com>
"""

import os
import sys
import glob
import math
import copy
import tempfile
import types

import wx

from grass.script import core as grass
from grass.script.utils import try_remove
from grass.pydispatch.signal import Signal

from core          import utils
from core.utils import _
from core.ws       import RenderWMSMgr
from core.gcmd     import GException, GError, RunCommand
from core.debug    import Debug
from core.settings import UserSettings


USE_GPNMCOMP = True


class Layer(object):
    """Virtual class which stores information about layers (map layers and
    overlays) of the map composition.

    - For map layer use MapLayer class.
    - For overlays use Overlay class.
    """
    def __init__(self, ltype, cmd, Map, name=None,
                 active=True, hidden=False, opacity=1.0):
        """Create new instance

        .. todo::

            pass cmd as tuple instead of list

        :param ltype: layer type ('raster', 'vector', 'overlay', 'command', etc.)
        :param cmd: GRASS command to render layer, given as list,
                    e.g. ['d.rast', 'map=elevation@PERMANENT']
        :param map: render.Map instance
        :param name: layer name, e.g. 'elevation@PERMANENT' (for layer tree)
        :param active: layer is active, will be rendered only if True
        :param hidden: layer is hidden, won't be listed in Layer Manager if True
        :param float opacity: layer opacity <0;1>
        """

        # generated file for each layer
        if USE_GPNMCOMP or ltype == 'overlay':
            if ltype == 'overlay':
                tempfile_sfx = ".png"
            else:
                tempfile_sfx = ".ppm"

            mapfile = tempfile.NamedTemporaryFile(suffix=tempfile_sfx, delete=False)
            # we don't want it open, we just need the name
            self.mapfile = mapfile.name
            mapfile.close()
            self.maskfile = self.mapfile.rsplit(".",1)[0] + ".pgm"
        else:
            self.mapfile = self.maskfile = None

        # stores class which manages rendering instead of simple command - e.g. WMS
        self.renderMgr = None

        self.Map = Map
        self.type = None
        self.SetType(ltype)
        self.name = name
        self.environ = os.environ.copy()

        if self.type == 'command':
            self.cmd = list()
            for c in cmd:
                self.cmd.append(utils.CmdToTuple(c))
        else:
            self.cmd = utils.CmdToTuple(cmd)

        self.active  = active
        self.hidden  = hidden
        self.opacity = opacity

        self.forceRender = True

        Debug.msg (3, "Layer.__init__(): type=%s, cmd='%s', name=%s, " \
                       "active=%d, opacity=%d, hidden=%d" % \
                       (self.type, self.GetCmd(string=True), self.name,
                        self.active, self.opacity, self.hidden))

    def __del__(self):
        Debug.msg (3, "Layer.__del__(): layer=%s, cmd='%s'" %
                   (self.name, self.GetCmd(string = True)))

    def Render(self):
        """Render layer to image

        :return: rendered image filename
        :return: None on error or if cmdfile is defined
        """
        if not self.cmd:
            return None

        # ignore in 2D
        if self.type == '3d-raster':
            return None

        Debug.msg (3, "Layer.Render(): type=%s, name=%s" % \
                       (self.type, self.name))

        # prepare command for each layer
        layertypes = utils.command2ltype.values() + ['overlay', 'command']

        if self.type not in layertypes:
            raise GException(_("<%(name)s>: layer type <%(type)s> is not supported") % \
                                 {'type' : self.type, 'name' : self.name})

        if self.mapfile:
            self.environ["GRASS_RENDER_FILE"] = self.mapfile

        # execute command
        try:
            if self.type == 'command':
                read = False
                for c in self.cmd:
                    ret, msg = self._runCommand(c)
                    if ret != 0:
                        break
                    if not read:
                        self.environ["GRASS_RENDER_FILE_READ"] = "TRUE"

                self.environ["GRASS_RENDER_FILE_READ"] = "FALSE"
            else:
                ret, msg = self._runCommand(self.cmd)
            if ret != 0:
                sys.stderr.write(_("Command '%s' failed\n") % self.GetCmd(string = True))
                if msg:
                    sys.stderr.write(_("Details: %s\n") % msg)
                raise GException()

        except GException:
            # clean up after problems
            for f in [self.mapfile, self.maskfile]:
                if not f:
                    continue
                try_remove(f)
                f = None

        self.forceRender = False

        return self.mapfile

    def _runCommand(self, cmd):
        """Run command to render data
        """
        if self.type == 'wms':
            ret = 0
            msg = ''
            self.renderMgr.Render(cmd, env=self.environ)
        else:
            ret, msg = RunCommand(cmd[0],
                                  getErrorMsg = True,
                                  quiet = True,
                                  env=self.environ,
                                  **cmd[1])

        return ret, msg

    def GetCmd(self, string = False):
        """Get GRASS command as list of string.

        :param string: get command as string if True otherwise as list

        :return: command list/string
        """
        if string:
            if self.type == 'command':
                scmd = []
                for c in self.cmd:
                    scmd.append(utils.GetCmdString(c))

                return ';'.join(scmd)
            else:
                return utils.GetCmdString(self.cmd)
        else:
            return self.cmd

    def GetType(self):
        """Get map layer type"""
        return self.type

    def GetElement(self):
        """Get map element type"""
        if self.type == 'raster':
            return 'cell'
        return self.type

    def GetOpacity(self):
        """
        Get layer opacity level

        :return: opacity level (<0, 1>)
        """
        return self.opacity

    def GetName(self, fullyQualified = True):
        """Get map layer name

        :param bool fullyQualified: True to return fully qualified name
                                    as a string 'name@mapset' otherwise
                                    directory { 'name', 'mapset' } is
                                    returned

        :return: string / directory
        """
        if fullyQualified:
            return self.name
        else:
            if '@' in self.name:
                return { 'name' : self.name.split('@')[0],
                         'mapset' : self.name.split('@')[1] }
            else:
                return { 'name' : self.name,
                         'mapset' : '' }

    def IsActive(self):
        """Check if layer is activated for rendering"""
        return self.active

    def IsHidden(self):
        """Check if layer is hidden"""
        return self.hidden

    def SetType(self, ltype):
        """Set layer type"""
        if ltype not in utils.command2ltype.values() + ['overlay', 'command']:
            raise GException(_("Unsupported map layer type '%s'") % ltype)

        if ltype == 'wms' and not isinstance(self.renderMgr, RenderWMSMgr):
            self.renderMgr = RenderWMSMgr(layer=self,
                                          mapfile=self.mapfile,
                                          maskfile=self.maskfile)
        elif self.type == 'wms' and ltype != 'wms':
            self.renderMgr = None

        self.type = ltype

    def SetName(self, name):
        """Set layer name"""
        self.name = name

    def SetActive(self, enable = True):
        """Active or deactive layer"""
        self.active = bool(enable)

    def SetHidden(self, enable = False):
        """Hide or show map layer in Layer Manager"""
        self.hidden = bool(enable)

    def SetOpacity(self, value):
        """Set opacity value"""
        if value < 0:
            value = 0.
        elif value > 1:
            value = 1.

        self.opacity = float(value)

    def SetCmd(self, cmd):
        """Set new command for layer"""
        if self.type == 'command':
            self.cmd = []
            for c in cmd:
                self.cmd.append(utils.CmdToTuple(c))
        else:
            self.cmd = utils.CmdToTuple(cmd)
        Debug.msg(3, "Layer.SetCmd(): cmd='%s'" % self.GetCmd(string = True))

        # for re-rendering
        self.forceRender = True

    def SetEnvironment(self, environ):
        """Sets environment for rendering."""
        self.environ = environ

    def IsDownloading(self):
        """Is data downloading from web server e. g. wms"""
        if self.renderMgr is None:
            return False
        else:
            return self.renderMgr.IsDownloading()

    def AbortThread(self):
        """Abort running thread e. g. downloading data"""
        if self.renderMgr is None:
            return
        else:
            self.renderMgr.Abort()

    def GetRenderMgr(self):
        """Get render manager """
        return self.renderMgr

class MapLayer(Layer):
    def __init__(self, ltype, cmd, Map, name = None,
                 active = True, hidden = False, opacity = 1.0):
        """Represents map layer in the map canvas

        :param ltype: layer type ('raster', 'vector', 'command', etc.)
        :param cmd: GRASS command to render layer,
                    given as list, e.g. ['d.rast',
                    'map=elevation@PERMANENT']
        :param map: render.Map instance
        :param name: layer name, e.g. 'elevation@PERMANENT' (for layer tree) or None
        :param active: layer is active, will be rendered only if True
        :param hidden: layer is hidden, won't be listed in Layer Manager if True
        :param opacity: layer opacity <0;1>
        """
        Layer.__init__(self, ltype, cmd, Map, name,
                       active, hidden, opacity)

    def GetMapset(self):
        """Get mapset of map layer

        :return: mapset name
        :return: '' on error (no name given)
        """
        if not self.name:
            return ''

        try:
            return self.name.split('@')[1]
        except IndexError:
            return self.name

class Overlay(Layer):
    def __init__(self, id, ltype, cmd, Map,
                 active = True, hidden = True, opacity = 1.0):
        """Represents overlay displayed in map canvas

        :param id: overlay id (for PseudoDC)
        :param type: overlay type ('barscale', 'legend', etc.)
        :param cmd: GRASS command to render overlay,
                    given as list, e.g. ['d.legend',
                    'rast=elevation@PERMANENT']
        :param map: render.Map instance
        :param active: layer is active, will be rendered only if True
        :param hidden: layer is hidden, won't be listed in Layer Manager if True
        :param opacity: layer opacity <0;1>
        """
        Layer.__init__(self, 'overlay', cmd, Map, ltype,
                       active, hidden, opacity)
        self.id = id

class Map(object):
    def __init__(self, gisrc = None):
        """Map composition (stack of map layers and overlays)

        :param gisrc: alternative gisrc (used eg. by georectifier)
        """
        # region/extent settigns
        self.wind      = dict() # WIND settings (wind file)
        self.region    = dict() # region settings (g.region)
        self.width     = 640    # map width
        self.height    = 480    # map height

        # list of layers
        self.layers    = list()  # stack of available GRASS layer

        self.overlays  = list()  # stack of available overlays
        self.ovlookup  = dict()  # lookup dictionary for overlay items and overlays

        # path to external gisrc
        self.gisrc = gisrc

        # generated file for g.pnmcomp output for rendering the map
        self.mapfile = grass.tempfile(create = False) + '.ppm'

        # setting some initial env. variables
        if not self.GetWindow():
            sys.stderr.write(_("Trying to recover from default region..."))
            RunCommand('g.region', flags='d')

        # info to report progress
        self.progressInfo = None

        # GRASS environment variable (for rendering)
        self.default_env = {"GRASS_RENDER_BACKGROUNDCOLOR" : "000000",
                            "GRASS_RENDER_FILE_COMPRESSION" : "0",
                            "GRASS_RENDER_TRUECOLOR"       : "TRUE",
                            "GRASS_RENDER_TRANSPARENT"     : "TRUE"
                            }

        # projection info
        self.projinfo = self._projInfo()

        # is some layer being downloaded?
        self.downloading = False

        self.layerChanged = Signal('Map.layerChanged')
        self.updateProgress = Signal('Map.updateProgress')
        self.layerRemoved = Signal('Map:layerRemoved')
        self.layerAdded = Signal('Map:layerAdded')

    def GetProjInfo(self):
        """Get projection info"""
        return self.projinfo

    def _projInfo(self):
        """Return region projection and map units information
        """
        projinfo = dict()
        if not grass.find_program('g.proj', '--help'):
            sys.exit(_("GRASS module '%s' not found. Unable to start map "
                       "display window.") % 'g.proj')
        env = os.environ.copy()
        if self.gisrc:
            env['GISRC'] = self.gisrc
        ret = RunCommand(prog='g.proj', read=True, flags='p', env=env)

        if not ret:
            return projinfo

        for line in ret.splitlines():
            if ':' in line:
                key, val = map(lambda x: x.strip(), line.split(':'))
                if key in ['units']:
                    val = val.lower()
                projinfo[key] = val
            elif "XY location (unprojected)" in line:
                projinfo['proj'] = 'xy'
                projinfo['units'] = ''
                break

        return projinfo

    def GetWindow(self):
        """Read WIND file and set up self.wind dictionary"""
        # FIXME: duplicated region WIND == g.region (at least some values)
        env = grass.gisenv()
        filename = os.path.join (env['GISDBASE'],
                                 env['LOCATION_NAME'],
                                 env['MAPSET'],
                                 "WIND")
        try:
            windfile = open (filename, "r")
        except IOError as e:
            sys.exit(_("Error: Unable to open '%(file)s'. Reason: %(ret)s. wxGUI exited.\n") % \
                         { 'file' : filename, 'ret' : e})

        for line in windfile.readlines():
            line = line.strip()
            try:
                key, value = line.split(":", 1)
            except ValueError as e:
                sys.stderr.write(_("\nERROR: Unable to read WIND file: %s\n") % e)
                return None

            self.wind[key.strip()] = value.strip()

        windfile.close()

        return self.wind

    def AdjustRegion(self):
        """Adjusts display resolution to match monitor size in
        pixels. Maintains constant display resolution, not related to
        computational region. Do NOT use the display resolution to set
        computational resolution. Set computational resolution through
        g.region.
        """
        mapwidth    = abs(self.region["e"] - self.region["w"])
        mapheight   = abs(self.region['n'] - self.region['s'])

        self.region["nsres"] =  mapheight / self.height
        self.region["ewres"] =  mapwidth  / self.width
        self.region['rows']  = round(mapheight / self.region["nsres"])
        self.region['cols']  = round(mapwidth / self.region["ewres"])
        self.region['cells'] = self.region['rows'] * self.region['cols']

        Debug.msg (3, "Map.AdjustRegion(): %s" % self.region)

        return self.region

    def AlignResolution(self):
        """Sets display extents to even multiple of current
        resolution defined in WIND file from SW corner. This must be
        done manually as using the -a flag can produce incorrect
        extents.
        """
        # new values to use for saving to region file
        new = {}
        n = s = e = w = 0.0
        nsres = ewres = 0.0

        # Get current values for region and display
        reg = self.GetRegion()
        nsres = reg['nsres']
        ewres = reg['ewres']

        n = float(self.region['n'])
        s = float(self.region['s'])
        e = float(self.region['e'])
        w = float(self.region['w'])

        # Calculate rows, columns, and extents
        new['rows'] = math.fabs(round((n-s)/nsres))
        new['cols'] = math.fabs(round((e-w)/ewres))

        # Calculate new extents
        new['s'] = nsres * round(s / nsres)
        new['w'] = ewres * round(w / ewres)
        new['n'] = new['s'] + (new['rows'] * nsres)
        new['e'] = new['w'] + (new['cols'] * ewres)

        return new

    def AlignExtentFromDisplay(self):
        """Align region extent based on display size from center
        point"""
        # calculate new bounding box based on center of display
        if self.region["ewres"] > self.region["nsres"]:
            res = self.region["ewres"]
        else:
            res = self.region["nsres"]

        Debug.msg(3, "Map.AlignExtentFromDisplay(): width=%d, height=%d, res=%f, center=%f,%f" % \
                      (self.width, self.height, res, self.region['center_easting'],
                       self.region['center_northing']))

        ew = (self.width / 2) * res
        ns = (self.height / 2) * res

        self.region['n'] = self.region['center_northing'] + ns
        self.region['s'] = self.region['center_northing'] - ns
        self.region['e'] = self.region['center_easting'] + ew
        self.region['w'] = self.region['center_easting'] - ew

        # LL locations
        if self.projinfo['proj'] == 'll':
            self.region['n'] = min(self.region['n'], 90.0)
            self.region['s'] = max(self.region['s'], -90.0)

    def ChangeMapSize(self, size):
        """Change size of rendered map.

        :param size: map size given as tuple
        """
        try:
            self.width  = int(size[0])
            self.height = int(size[1])
            if self.width < 1 or self.height < 1:
                sys.stderr.write(_("Invalid map size %d,%d\n") % (self.width, self.height))
                raise ValueError
        except ValueError:
            self.width  = 640
            self.height = 480

        Debug.msg(2, "Map.ChangeMapSize(): width=%d, height=%d" % \
                      (self.width, self.height))

    def GetRegion(self, rast=None, zoom=False, vect=None, rast3d=None, regionName=None,
                  n=None, s=None, e=None, w=None, default=False,
                  update=False, add3d=False):
        """Get region settings (g.region -upgc)

        Optionally extent, raster or vector map layer can be given.

        :param rast: list of raster maps
        :param zoom: zoom to raster map (ignore NULLs)
        :param vect: list of vector maps
        :param rast3d: 3d raster map (not list, no support of multiple 3d rasters in g.region)
        :param regionName:  named region or None
        :param n,s,e,w: force extent
        :param default: force default region settings
        :param update: if True update current display region settings
        :param add3d: add 3d region settings

        :return: region settings as dictionary, e.g. {
                 'n':'4928010', 's':'4913700', 'w':'589980',...}

        :func:`GetCurrentRegion()`
        """
        region = {}

        env = os.environ.copy()
        if self.gisrc:
            env['GISRC'] = self.gisrc

        # do not update & shell style output
        cmd = {}
        cmd['flags'] = 'ugpc'

        if default:
            cmd['flags'] += 'd'

        if add3d:
            cmd['flags'] += '3'

        if regionName:
            cmd['region'] = regionName

        if n:
            cmd['n'] = n
        if s:
            cmd['s'] = s
        if e:
            cmd['e'] = e
        if w:
            cmd['w'] = w

        if rast:
            if zoom:
                cmd['zoom'] = rast[0]
            else:
                cmd['rast'] = ','.join(rast)

        if vect:
            cmd['vect'] = ','.join(vect)

        if rast3d:
            cmd['rast3d'] = rast3d

        ret, reg, msg = RunCommand('g.region',
                                   read = True,
                                   getErrorMsg = True,
                                   env=env,
                                   **cmd)

        if ret != 0:
            if rast:
                message = _("Unable to zoom to raster map <%s>.") % rast[0] + \
                    "\n\n" + _("Details:") + " %s" % msg
            elif vect:
                message = _("Unable to zoom to vector map <%s>.") % vect[0] + \
                    "\n\n" + _("Details:") + " %s" % msg
            elif rast3d:
                message = _("Unable to zoom to 3d raster map <%s>.") % rast3d + \
                    "\n\n" + _("Details:") + " %s" % msg
            else:
                message = _("Unable to get current geographic extent. "
                            "Force quiting wxGUI. Please manually run g.region to "
                            "fix the problem.")
            GError(message)
            return self.region

        for r in reg.splitlines():
            key, val = r.split("=", 1)
            try:
                region[key] = float(val)
            except ValueError:
                region[key] = val

        Debug.msg (3, "Map.GetRegion(): %s" % region)

        if update:
            self.region = region

        return region

    def GetCurrentRegion(self):
        """Get current display region settings

        :func:`GetRegion()`
        """
        return self.region

    def SetRegion(self, windres = False, windres3 = False):
        """Render string for GRASS_REGION env. variable, so that the
        images will be rendered from desired zoom level.

        :param windres: uses resolution from WIND file rather than
                        display (for modules that require set resolution
                        like d.rast.num)

        :return: String usable for GRASS_REGION variable or None
        """
        grass_region = ""

        if windres:
            compRegion = self.GetRegion(add3d = windres3)
            region = copy.copy(self.region)
            for key in ('nsres', 'ewres', 'cells'):
                region[key] = compRegion[key]
            if windres3:
                for key in ('nsres3', 'ewres3', 'tbres', 'cells3',
                            'cols3', 'rows3', 'depths'):
                    if key in compRegion:
                        region[key] = compRegion[key]

        else:
            # adjust region settings to match monitor
            region = self.AdjustRegion()

        # read values from wind file
        try:
            for key in self.wind.keys():

                if key == 'north':
                    grass_region += "north: %s; " % \
                        (region['n'])
                    continue
                elif key == "south":
                    grass_region += "south: %s; " % \
                        (region['s'])
                    continue
                elif key == "east":
                    grass_region += "east: %s; " % \
                        (region['e'])
                    continue
                elif key == "west":
                    grass_region += "west: %s; " % \
                        (region['w'])
                    continue
                elif key == "e-w resol":
                    grass_region += "e-w resol: %f; " % \
                        (region['ewres'])
                    continue
                elif key == "n-s resol":
                    grass_region += "n-s resol: %f; " % \
                        (region['nsres'])
                    continue
                elif key == "cols":
                    if windres:
                        continue
                    grass_region += 'cols: %d; ' % \
                        region['cols']
                    continue
                elif key == "rows":
                    if windres:
                        continue
                    grass_region += 'rows: %d; ' % \
                        region['rows']
                    continue
                elif key == "n-s resol3" and windres3:
                    grass_region += "n-s resol3: %f; " % \
                        (region['nsres3'])
                elif key == "e-w resol3" and windres3:
                    grass_region += "e-w resol3: %f; " % \
                        (region['ewres3'])
                elif key == "t-b resol" and windres3:
                    grass_region += "t-b resol: %f; " % \
                        (region['tbres'])
                elif key == "cols3" and windres3:
                    grass_region += "cols3: %d; " % \
                        (region['cols3'])
                elif key == "rows3" and windres3:
                    grass_region += "rows3: %d; " % \
                        (region['rows3'])
                elif key == "depths" and windres3:
                    grass_region += "depths: %d; " % \
                        (region['depths'])
                else:
                    grass_region += key + ": "  + self.wind[key] + "; "

            Debug.msg (3, "Map.SetRegion(): %s" % grass_region)

            return grass_region

        except:
            return None

    def GetListOfLayers(self, ltype = None, mapset = None, name = None,
                        active = None, hidden = None):
        """Returns list of layers of selected properties or list of
        all layers.

        :param ltype: layer type, e.g. raster/vector/wms/overlay (value or tuple of values)
        :param mapset: all layers from given mapset (only for maplayers)
        :param name: all layers with given name
        :param active: only layers with 'active' attribute set to True or False
        :param hidden: only layers with 'hidden' attribute set to True or False

        :return: list of selected layers
        """
        selected = []

        if type(ltype) == types.StringType:
            one_type = True
        else:
            one_type = False

        if one_type and ltype == 'overlay':
            llist = self.overlays
        else:
            llist = self.layers

        # ["raster", "vector", "wms", ... ]
        for layer in llist:
            # specified type only
            if ltype != None:
                if one_type and layer.type != ltype:
                    continue
                elif not one_type and layer.type not in ltype:
                    continue

            # mapset
            if (mapset != None and ltype != 'overlay') and \
                    layer.GetMapset() != mapset:
                continue

            # name
            if name != None and layer.name != name:
                continue

            # hidden and active layers
            if active != None and \
                   hidden != None:
                if layer.active == active and \
                       layer.hidden == hidden:
                    selected.append(layer)

            # active layers
            elif active != None:
                if layer.active == active:
                    selected.append(layer)

            # hidden layers
            elif hidden != None:
                if layer.hidden == hidden:
                    selected.append(layer)

            # all layers
            else:
                selected.append(layer)

        Debug.msg (3, "Map.GetListOfLayers(): numberof=%d" % len(selected))

        return selected

    def _renderLayers(self, env, force = False, overlaysOnly = False):
        """Render all map layers into files

        :param bool force: True to force rendering
        :param bool overlaysOnly: True to render only overlays

        :return: list of maps, masks and opacities
        """
        maps = list()
        masks = list()
        opacities = list()
        # render map layers
        if overlaysOnly:
            layers = self.overlays
        else:
            layers = self.layers + self.overlays

        self.downloading = False

        self.ReportProgress(layer=None)


        for layer in layers:
            # skip non-active map layers
            if not layer or not layer.active:
                continue

            # render
            if force or layer.forceRender:
                layer.SetEnvironment(env)
                if not layer.Render():
                    continue

            if layer.IsDownloading():
                self.downloading = True

            self.ReportProgress(layer=layer)

            # skip map layers when rendering fails
            if not os.path.exists(layer.mapfile):
                continue

            # add image to compositing list
            if layer.type != "overlay":
                maps.append(layer.mapfile)
                masks.append(layer.maskfile)
                opacities.append(str(layer.opacity))

            Debug.msg(3, "Map.Render() type=%s, layer=%s " % (layer.type, layer.name))

        return maps, masks, opacities

    def GetMapsMasksAndOpacities(self, force, windres, env):
        """
        Used by Render function.

        :return: maps, masks, opacities
        """
        return self._renderLayers(force=force, env=env)

    def Render(self, force = False, windres = False):
        """Creates final image composite

        This function can conditionaly use high-level tools, which
        should be avaliable in wxPython library

        :param force: force rendering
        :param windres: use region resolution (True) otherwise display
                        resolution

        :return: name of file with rendered image or None
        """
        wx.BeginBusyCursor()
        env = os.environ.copy()
        env.update(self.default_env)
        # use external gisrc if defined
        if self.gisrc:
            env['GISRC'] = self.gisrc
        env['GRASS_REGION'] = self.SetRegion(windres)
        env['GRASS_RENDER_WIDTH'] = str(self.width)
        env['GRASS_RENDER_HEIGHT'] = str(self.height)
        driver = UserSettings.Get(group = 'display', key = 'driver', subkey = 'type')
        if driver == 'png':
            env['GRASS_RENDER_IMMEDIATE'] = 'png'
        else:
            env['GRASS_RENDER_IMMEDIATE'] = 'cairo'

        maps, masks, opacities = self.GetMapsMasksAndOpacities(force, windres, env)

        # ugly hack for MSYS
        if sys.platform != 'win32':
            mapstr = ",".join(maps)
            maskstr = ",".join(masks)
        else:
            mapstr = ""
            for item in maps:
                mapstr += item.replace('\\', '/')
            mapstr = mapstr.rstrip(',')
            maskstr = ""
            for item in masks:
                maskstr += item.replace('\\', '/')
            maskstr = maskstr.rstrip(',')

        # run g.pngcomp to get composite image
        bgcolor = ':'.join(map(str, UserSettings.Get(group = 'display', key = 'bgcolor',
                                                     subkey = 'color')))

        if maps:
            ret, msg = RunCommand('g.pnmcomp',
                                  getErrorMsg = True,
                                  overwrite = True,
                                  input = '%s' % ",".join(maps),
                                  mask = '%s' % ",".join(masks),
                                  opacity = '%s' % ",".join(opacities),
                                  bgcolor = bgcolor,
                                  width = self.width,
                                  height = self.height,
                                  output = self.mapfile,
                                  env=env)

            if ret != 0:
                print >> sys.stderr, _("ERROR: Rendering failed. Details: %s") % msg
                wx.EndBusyCursor()
                return None

        Debug.msg (3, "Map.Render() force=%s file=%s" % (force, self.mapfile))

        wx.EndBusyCursor()
        if not maps:
            return None

        return self.mapfile

    def AddLayer(self, ltype, command, name = None,
                 active = True, hidden = False, opacity = 1.0, render = False,
                 pos = -1):
        """Adds generic map layer to list of layers

        :param ltype: layer type ('raster', 'vector', etc.)
        :param command:  GRASS command given as list
        :param name: layer name
        :param active: layer render only if True
        :param hidden: layer not displayed in layer tree if True
        :param opacity: opacity level range from 0(transparent) - 1(not transparent)
        :param render: render an image if True
        :param pos: position in layer list (-1 for append)

        :return: new layer on success
        :return: None on failure
        """
        wx.BeginBusyCursor()
        # opacity must be <0;1>
        if opacity < 0:
            opacity = 0
        elif opacity > 1:
            opacity = 1
        layer = MapLayer(ltype = ltype, name = name, cmd = command, Map = self,
                         active = active, hidden = hidden, opacity = opacity)

        # add maplayer to the list of layers
        if pos > -1:
            self.layers.insert(pos, layer)
        else:
            self.layers.append(layer)

        Debug.msg (3, "Map.AddLayer(): layer=%s" % layer.name)
        if render:
            if not layer.Render():
                raise GException(_("Unable to render map layer <%s>.") % name)

        renderMgr = layer.GetRenderMgr()
        if renderMgr:
            renderMgr.dataFetched.connect(self.layerChanged)
            renderMgr.updateProgress.connect(self.ReportProgress)

        wx.EndBusyCursor()

        self.layerAdded.emit(layer=layer)

        return layer

    def DeleteAllLayers(self, overlay = False):
        """Delete all layers

        :param overlay: True to delete also overlayes
        """
        self.layers = []
        if overlay:
            self.overlays = []

    def DeleteLayer(self, layer, overlay = False):
        """Removes layer from list of layers

        :param layer: layer instance in layer tree
        :param overlay: delete overlay (use self.DeleteOverlay() instead)

        :return: removed layer on success or None
        """
        Debug.msg (3, "Map.DeleteLayer(): name=%s" % layer.name)

        if overlay:
            list = self.overlays
        else:
            list = self.layers

        if layer in list:
            if layer.mapfile:
                base = os.path.split(layer.mapfile)[0]
                mapfile = os.path.split(layer.mapfile)[1]
                tempbase = mapfile.split('.')[0]
                if base == '' or tempbase == '':
                    return None
                basefile = os.path.join(base, tempbase) + r'.*'
                for f in glob.glob(basefile):
                    os.remove(f)
            list.remove(layer)

            self.layerRemoved.emit(layer=layer)
            return layer

        return None

    def SetLayers(self, layers):
        self.layers = layers

        # only for debug
        # might be removed including message, it seems more than clear
        layerNameList = ""
        for layer in self.layers:
            if layer.GetName():
                layerNameList += layer.GetName() + ','
        Debug.msg(5, "Map.SetLayers(): layers=%s" % (layerNameList))

    def ChangeLayer(self, layer, render = False, **kargs):
        """Change map layer properties

        :param layer: map layer instance
        :param ltype: layer type ('raster', 'vector', etc.)
        :param command:  GRASS command given as list
        :param name: layer name
        :param active: layer render only if True
        :param hidden: layer not displayed in layer tree if True
        :param opacity: opacity level range from 0(transparent) - 1(not transparent)
        :param render: render an image if True
        """
        Debug.msg (3, "Map.ChangeLayer(): layer=%s" % layer.name)

        if 'ltype' in kargs:
            layer.SetType(kargs['ltype']) # check type

        if 'command' in kargs:
            layer.SetCmd(kargs['command'])

        if 'name' in kargs:
            layer.SetName(kargs['name'])

        if 'active' in kargs:
            layer.SetActive(kargs['active'])

        if 'hidden' in kargs:
            layer.SetHidden(kargs['hidden'])

        if 'opacity' in kargs:
            layer.SetOpacity(kargs['opacity'])

        if render and not layer.Render():
            raise GException(_("Unable to render map layer <%s>.") %
                             layer.GetName())

        self.layerChanged(layer=layer)
        return layer

    def ChangeOpacity(self, layer, opacity):
        """Changes opacity value of map layer

        :param layer: layer instance in layer tree
        :param opacity: opacity level <0;1>
        """
        # opacity must be <0;1>
        if opacity < 0: opacity = 0
        elif opacity > 1: opacity = 1

        layer.opacity = opacity
        Debug.msg (3, "Map.ChangeOpacity(): layer=%s, opacity=%f" % \
                   (layer.name, layer.opacity))

    def ChangeLayerActive(self, layer, active):
        """Enable or disable map layer

        :param layer: layer instance in layer tree
        :param active: to be rendered (True)
        """
        layer.active = active

        Debug.msg (3, "Map.ChangeLayerActive(): name='%s' -> active=%d" % \
                   (layer.name, layer.active))

    def ChangeLayerName (self, layer, name):
        """Change name of the layer

        :param layer: layer instance in layer tree
        :param name:  layer name to set up
        """
        Debug.msg (3, "Map.ChangeLayerName(): from=%s to=%s" % \
                   (layer.name, name))
        layer.name =  name

    def RemoveLayer(self, name = None, id = None):
        """Removes layer from layer list

        Layer is defined by name@mapset or id.

        :param name: layer name (must be unique)
        :param id: layer index in layer list def __init__(self,
                   targetFile, region, bandsNum, gdalDriver,
                   fillValue = None):

        :return: removed layer on success
        :return: None on failure
        """
        # delete by name
        if name:
            retlayer = None
            for layer in self.layers:
                if layer.name == name:
                    retlayer = layer
                    os.remove(layer.mapfile)
                    os.remove(layer.maskfile)
                    self.layers.remove(layer)
                    return retlayer
        # del by id
        elif id != None:
            return self.layers.pop(id)

        return None

    def GetLayerIndex(self, layer, overlay = False):
        """Get index of layer in layer list.

        :param layer: layer instace in layer tree
        :param overlay: use list of overlays instead

        :return: layer index
        :return: -1 if layer not found
        """
        if overlay:
            list = self.overlays
        else:
            list = self.layers

        if layer in list:
            return list.index(layer)

        return -1

    def AddOverlay(self, id, ltype, command,
                   active = True, hidden = True, opacity = 1.0, render = False):
        """Adds overlay (grid, barscale, legend, etc.) to list of
        overlays

        :param id: overlay id (PseudoDC)
        :param ltype: overlay type (barscale, legend)
        :param command: GRASS command to render overlay
        :param active: overlay activated (True) or disabled (False)
        :param hidden: overlay is not shown in layer tree (if True)
        :param render: render an image (if True)

        :return: new layer on success
        :return: None on failure
        """
        Debug.msg (2, "Map.AddOverlay(): cmd=%s, render=%d" % (command, render))
        overlay = Overlay(id = id, ltype = ltype, cmd = command, Map = self,
                          active = active, hidden = hidden, opacity = opacity)

        # add maplayer to the list of layers
        self.overlays.append(overlay)

        if render and command != '' and not overlay.Render():
            raise GException(_("Unable to render overlay <%s>.") %
                             ltype)

        return self.overlays[-1]

    def ChangeOverlay(self, id, render = False, **kargs):
        """Change overlay properities

        Add new overlay if overlay with 'id' doesn't exist.

        :param id: overlay id (PseudoDC)
        :param ltype: overlay ltype (barscale, legend)
        :param command: GRASS command to render overlay
        :param active: overlay activated (True) or disabled (False)
        :param hidden: overlay is not shown in layer tree (if True)
        :param render: render an image (if True)

        :return: new layer on success
        """
        overlay = self.GetOverlay(id, list = False)
        if  overlay is None:
            overlay = Overlay(id, ltype = None, cmd = None)

        if 'ltype' in kargs:
            overlay.SetName(kargs['ltype']) # ltype -> overlay

        if 'command' in kargs:
            overlay.SetCmd(kargs['command'])

        if 'active' in kargs:
            overlay.SetActive(kargs['active'])

        if 'hidden' in kargs:
            overlay.SetHidden(kargs['hidden'])

        if 'opacity' in kargs:
            overlay.SetOpacity(kargs['opacity'])

        if render and overlay.GetCmd() != [] and not overlay.Render():
            raise GException(_("Unable to render overlay <%s>.") %
                             overlay.GetType())

        return overlay

    def GetOverlay(self, id, list=False):
        """Return overlay(s) with 'id'

        :param id: overlay id
        :param list: return list of overlays of True
                     otherwise suppose 'id' to be unique

        :return: list of overlays (list=True)
        :return: overlay (list=False)
        :return: None (list=False) if no overlay or more overlays found
        """
        ovl = []
        for overlay in self.overlays:
            if overlay.id == id:
                ovl.append(overlay)

        if not list:
            if len(ovl) != 1:
                return None
            else:
                return ovl[0]

        return ovl

    def DeleteOverlay(self, overlay):
        """Delete overlay

        :param overlay: overlay layer

        :return: removed overlay on success or None
        """
        return self.DeleteLayer(overlay, overlay = True)

    def _clean(self, llist):
        for layer in llist:
            if layer.maskfile:
                try_remove(layer.maskfile)
            if layer.mapfile:
                try_remove(layer.mapfile)
            llist.remove(layer)

    def Clean(self):
        """Clean layer stack - go trough all layers and remove them
        from layer list.

        Removes also mapfile and maskfile.
        """
        self._clean(self.layers)
        self._clean(self.overlays)

    def ReverseListOfLayers(self):
        """Reverse list of layers"""
        return self.layers.reverse()

    def RenderOverlays(self, force):
        """Render overlays only (for nviz)"""
        for layer in self.overlays:
            if force or layer.forceRender:
                layer.Render()

    def AbortAllThreads(self):
        """Abort all layers threads e. g. donwloading data"""
        for l in self.layers + self.overlays:
            l.AbortThread()

    def ReportProgress(self, layer):
        """Calculates progress in rendering/downloading
        and emits signal to inform progress bar about progress.
        """
        if self.progressInfo is None or layer is None:
            self.progressInfo = {'progresVal' : 0, # current progress value
                                 'downloading' : [], # layers, which are downloading data
                                 'rendered' : [], # already rendered layers
                                 'range' : len(self.GetListOfLayers(active = True)) +
                                           len(self.GetListOfLayers(active = True, ltype = 'overlay')) -
                                           len(self.GetListOfLayers(active = True, ltype = '3d-raster'))}
        else:
            if layer not in self.progressInfo['rendered']:
                self.progressInfo['rendered'].append(layer)
            if layer.IsDownloading() and \
                    layer not in self.progressInfo['downloading']:
                self.progressInfo['downloading'].append(layer)
            else:
                self.progressInfo['progresVal'] += 1
                if layer in self.progressInfo['downloading']:
                    self.progressInfo['downloading'].remove(layer)

        # for updating statusbar text
        stText = ''
        first = True
        for layer in self.progressInfo['downloading']:
            if first:
                stText += _("Downloading data ")
                first = False
            else:
                stText += ', '
            stText += '<%s>' % layer.GetName()
        if stText:
            stText += '...'

        if  self.progressInfo['range'] != len(self.progressInfo['rendered']):
            if stText:
                stText = _('Rendering & ') + stText
            else:
                stText = _('Rendering...')

        self.updateProgress.emit(range=self.progressInfo['range'],
                                 value=self.progressInfo['progresVal'],
                                 text=stText)