Skip to content
Permalink
Browse files

Oriented Minimum Bounding Box - processing version as requested #2116

Inverse field order for PERIMETER and ANGLE
  • Loading branch information
lbartoletti authored and slarosa committed Sep 12, 2015
1 parent 95e9ade commit 442bdfc05c67253cd0d136e60c2db27fbf52cf3d
@@ -0,0 +1,182 @@
# -*- coding: utf-8 -*-

"""
***************************************************************************
OrientedMinimumBoundingBox.py
---------------------
Date : June 2015
Copyright : (C) 2015, Loïc BARTOLETTI
Email : coder at tuxfamily dot org
***************************************************************************
* *
* 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. *
* *
***************************************************************************
"""

__author__ = 'Loïc BARTOLETTI'
__date__ = 'June 2015'
__copyright__ = '(C) 2015, Loïc BARTOLETTI'

# This will get replaced with a git SHA1 when you do a git archive

__revision__ = '$Format:%H$'

from PyQt4.QtCore import QVariant
from qgis.core import QGis, QgsField, QgsPoint, QgsGeometry, QgsFeature
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterVector
from processing.core.parameters import ParameterBoolean
from processing.core.outputs import OutputVector
from processing.tools import dataobjects, vector
from math import *



class OrientedMinimumBoundingBox(GeoAlgorithm):

INPUT_LAYER = 'INPUT_LAYER'
BY_FEATURE = 'BY_FEATURE'

OUTPUT = 'OUTPUT'

def defineCharacteristics(self):
self.name = 'Oriented Minimum Bounding Box'
self.group = 'Vector general tools'

self.addParameter(ParameterVector(self.INPUT_LAYER,
self.tr('Input layer'), [ParameterVector.VECTOR_TYPE_ANY]))
self.addParameter(ParameterBoolean(self.BY_FEATURE,
self.tr('Calculate OMBB for each feature separately'), True))

self.addOutput(OutputVector(self.OUTPUT, self.tr('Oriented_MBBox')))

def processAlgorithm(self, progress):
layer = dataobjects.getObjectFromUri(
self.getParameterValue(self.INPUT_LAYER))
byFeature = self.getParameterValue(self.BY_FEATURE)

if byFeature and layer.geometryType() == 0:
progress.setInfo(self.tr("Can't calculate an OMBB for each point, it's a point."))
byFeature = False

fields = [
QgsField('AREA', QVariant.Double),
QgsField('PERIMETER', QVariant.Double),
QgsField('ANGLE', QVariant.Double),
QgsField('WIDTH', QVariant.Double),
QgsField('HEIGHT', QVariant.Double),
]

writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(fields,
QGis.WKBPolygon, layer.crs())

if byFeature:
self.featureOmbb(layer, writer, progress)
else:
self.layerOmmb(layer, writer, progress)

del writer

def layerOmmb(self, layer, writer, progress):
current = 0
vprovider = layer.dataProvider()

fit = vprovider.getFeatures()
inFeat = QgsFeature()
total = 100.0 / float(vprovider.featureCount())
newgeometry = QgsGeometry()
first = True
while fit.nextFeature(inFeat):
if first:
newgeometry = QgsGeometry(inFeat.geometry())
first = False
else:
newgeometry = newgeometry.combine(inFeat.geometry())
current += 1
progress.setPercentage(int(current * total))

geometry, area, perim, angle, width, height = self.OMBBox(newgeometry)

if geometry:
outFeat = QgsFeature()

outFeat.setGeometry(geometry)
outFeat.setAttributes([ area,
perim,
angle,
width,
height])
writer.addFeature(outFeat)

def featureOmbb(self, layer, writer, progress):
current = 0
features = vector.features(layer)
total = 100.0 / float(len(features))
outFeat = QgsFeature()
inFeat = QgsFeature()
for inFeat in features:
geometry, area, perim, angle, width, height = self.OMBBox(
inFeat.geometry())
if geometry:
outFeat.setGeometry(geometry)
outFeat.setAttributes([ area,
perim,
angle,
width,
height])
writer.addFeature(outFeat)
else:
progress.setInfo(self.tr("Can't calculate an OMBB for features n°") + str(inFeat.id()) + ".")
current += 1
progress.setPercentage(int(current * total))

def GetAngleOfLineBetweenTwoPoints(self, p1, p2, angle_unit="degrees"):
xDiff = p2.x() - p1.x()
yDiff = p2.y() - p1.y()
if angle_unit == "radians":
return atan2(yDiff, xDiff)
else:
return degrees(atan2(yDiff, xDiff))

def OMBBox(self, geom):

g = geom.convexHull()

if g.type() != 2:
return None, None, None, None, None, None
r = g.asPolygon()[0]

p0 = QgsPoint(r[0][0], r[0][1])

i = 0
l = len(r)
OMBBox = QgsGeometry()
gBBox = g.boundingBox()
OMBBox_area = gBBox.height() * gBBox.width()
OMBBox_angle = 0
OMBBox_width = 0
OMBBox_heigth = 0
OMBBox_perim = 0
while i < l - 1:
x = QgsGeometry(g)
angle = self.GetAngleOfLineBetweenTwoPoints(r[i], r[i + 1])
x.rotate(angle, p0)
bbox = x.boundingBox()
bb = QgsGeometry.fromWkt(bbox.asWktPolygon())
bb.rotate(-angle, p0)

a = bb.area()
if a <= OMBBox_area:
OMBBox = QgsGeometry(bb)
OMBBox_area = a
OMBBox_angle = angle
OMBBox_width = bbox.width()
OMBBox_heigth = bbox.height()
OMBBox_perim = 2 * OMBBox_width + 2 * OMBBox_heigth
i += 1

return OMBBox, OMBBox_area, OMBBox_perim, OMBBox_angle, OMBBox_width, OMBBox_heigth
@@ -130,6 +130,7 @@
from FieldsMapper import FieldsMapper
from Datasources2Vrt import Datasources2Vrt
from CheckValidity import CheckValidity
from OrientedMinimumBoundingBox import OrientedMinimumBoundingBox

pluginPath = os.path.normpath(os.path.join(
os.path.split(os.path.dirname(__file__))[0], os.pardir))
@@ -177,8 +178,8 @@ def __init__(self):
SetVectorStyle(), SetRasterStyle(),
SelectByExpression(), HypsometricCurves(),
SplitLinesWithLines(), CreateConstantRaster(),
FieldsMapper(), SelectByAttributeSum(), Datasources2Vrt(),
CheckValidity()
FieldsMapper(),SelectByAttributeSum(), Datasources2Vrt(),
CheckValidity(), OrientedMinimumBoundingBox()
]

if hasMatplotlib:

0 comments on commit 442bdfc

Please sign in to comment.
You can’t perform that action at this time.