QGIS/python/plugins/sextante/core/QGisLayers.py
2013-02-24 16:42:34 +01:00

263 lines
9.1 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
QGisLayers.py
---------------------
Date : August 2012
Copyright : (C) 2012 by Victor Olaya
Email : volayaf at gmail dot com
***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************
"""
from sextante.gdal.GdalUtils import GdalUtils
__author__ = 'Victor Olaya'
__date__ = 'August 2012'
__copyright__ = '(C) 2012, Victor Olaya'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
from qgis.core import *
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from os import path
from sextante.core.SextanteConfig import SextanteConfig
class QGisLayers:
'''This class contains method to communicate SEXTANTE with the QGIS interface,
mostly for retrieving layers and adding new ones to the QGIS canvas'''
ALL_TYPES = -1
iface = None;
@staticmethod
def getSupportedOutputVectorLayerExtensions():
formats = QgsVectorFileWriter.supportedFiltersAndFormats()
exts = ["shp"]#shp is the default, should be the first
for extension in formats.keys():
extension = unicode(extension)
extension = extension[extension.find('*.') + 2:]
extension = extension[:extension.find(" ")]
if extension.lower() != "shp":
exts.append(extension)
return exts
@staticmethod
def getSupportedOutputRasterLayerExtensions():
allexts = ["tif"]
for exts in GdalUtils.getSupportedRasters().values():
for ext in exts:
if ext not in allexts:
allexts.append(ext)
return allexts
@staticmethod
def getSupportedOutputTableExtensions():
exts = ["csv"]
return exts
@staticmethod
def getRasterLayers():
layers = QGisLayers.iface.legendInterface().layers()
raster = list()
for layer in layers:
if layer.type() == layer.RasterLayer:
if layer.providerType() == 'gdal':#only gdal file-based layers
raster.append(layer)
return raster
@staticmethod
def getVectorLayers(shapetype=-1):
layers = QGisLayers.iface.legendInterface().layers()
vector = list()
for layer in layers:
if layer.type() == layer.VectorLayer:
if shapetype == QGisLayers.ALL_TYPES or layer.geometryType() == shapetype:
uri = unicode(layer.source())
if not uri.lower().endswith("csv") and not uri.lower().endswith("dbf"):
vector.append(layer)
return vector
@staticmethod
def getAllLayers():
layers = []
layers += QGisLayers.getRasterLayers();
layers += QGisLayers.getVectorLayers();
return layers
@staticmethod
def getTables():
layers = QGisLayers.iface.legendInterface().layers()
tables = list()
for layer in layers:
if layer.type() == layer.VectorLayer :
tables.append(layer)
return tables
@staticmethod
def setInterface(iface):
QGisLayers.iface = iface
@staticmethod
def loadList(layers):
for layer in layers:
QGisLayers.load(layer)
@staticmethod
def load(fileName, name = None, crs = None, style = None):
if fileName == None:
return
prjSetting = None
settings = QSettings()
if crs != None:
prjSetting = settings.value("/Projections/defaultBehaviour")
settings.setValue("/Projections/defaultBehaviour", QVariant(""))
if name == None:
name = path.split(fileName)[1]
qgslayer = QgsVectorLayer(fileName, name , 'ogr')
if qgslayer.isValid():
if crs is not None and qgslayer.crs() is None:
qgslayer.setCrs(crs, False)
if style == None:
if qgslayer.geometryType == 0:
style = SextanteConfig.getSetting(SextanteConfig.VECTOR_POINT_STYLE)
elif qgslayer.geometryType == 1:
style = SextanteConfig.getSetting(SextanteConfig.VECTOR_LINE_STYLE)
else:
style = SextanteConfig.getSetting(SextanteConfig.VECTOR_POLYGON_STYLE)
qgslayer.loadNamedStyle(style)
QgsMapLayerRegistry.instance().addMapLayers([qgslayer])
else:
qgslayer = QgsRasterLayer(fileName, name)
if qgslayer.isValid():
if crs != None:
qgslayer.setCrs(crs,False)
if style == None:
style = SextanteConfig.getSetting(SextanteConfig.RASTER_STYLE)
qgslayer.loadNamedStyle(style)
QgsMapLayerRegistry.instance().addMapLayers([qgslayer])
QGisLayers.iface.legendInterface().refreshLayerSymbology(qgslayer)
else:
if prjSetting:
settings.setValue("/Projections/defaultBehaviour", prjSetting)
raise RuntimeError("Could not load layer: " + unicode(fileName)
+"\nCheck the SEXTANTE log to look for errors")
if prjSetting:
settings.setValue("/Projections/defaultBehaviour", prjSetting)
return qgslayer
#===========================================================================
# @staticmethod
# def loadFromDict(layersdict, crs = None):
# for name in layersdict.keys():
# QGisLayers.load(layersdict[name], name, crs)
#===========================================================================
@staticmethod
def getObjectFromUri(uri, forceLoad = True):
if uri is None:
return None
layers = QGisLayers.getRasterLayers()
for layer in layers:
if layer.source() == uri:
return layer
layers = QGisLayers.getVectorLayers()
for layer in layers:
if layer.source() == uri:
return layer
tables = QGisLayers.getTables()
for table in tables:
if table.source() == uri:
return table
if forceLoad:
settings = QSettings()
prjSetting = settings.value("/Projections/defaultBehaviour")
settings.setValue("/Projections/defaultBehaviour", QVariant(""))
#if is not opened, we open it
layer = QgsVectorLayer(uri, uri , 'ogr')
if layer.isValid():
if prjSetting:
settings.setValue("/Projections/defaultBehaviour", prjSetting)
return layer
layer = QgsRasterLayer(uri, uri)
if layer.isValid():
if prjSetting:
settings.setValue("/Projections/defaultBehaviour", prjSetting)
return layer
if prjSetting:
settings.setValue("/Projections/defaultBehaviour", prjSetting)
else:
return None
@staticmethod
def features(layer):
'''this returns an iterator over features in a vector layer, considering the
selection that might exist in the layer, and the SEXTANTE configuration that
indicates whether to use only selected feature or all of them.
This should be used by algorithms instead of calling the QGis API directly,
to ensure a consistent behaviour across algorithms'''
return Features(layer)
class Features():
def __init__(self, layer):
self.layer = layer
self.iter = layer.getFeatures()
self.selection = False;
##self.layer.dataProvider().rewind()
if SextanteConfig.getSetting(SextanteConfig.USE_SELECTED):
self.selected = layer.selectedFeatures()
if len(self.selected) > 0:
self.selection = True
self.idx = 0;
def __iter__(self):
return self
def next(self):
if self.selection:
if self.idx < len(self.selected):
feature = self.selected[self.idx]
self.idx += 1
return feature
else:
raise StopIteration()
else:
if self.iter.isClosed():
raise StopIteration()
f = QgsFeature()
if self.iter.nextFeature(f):
return f
else:
self.iter.close()
raise StopIteration()
def __len__(self):
if self.selection:
return int(self.layer.selectedFeatureCount())
else:
return int(self.layer.featureCount())