source: development/momentum_sink/create_buildings.py @ 2465

import Numeric
import math
import random
# add inundation dir to your pythonpath
from pmesh.mesh import Mesh
from coordinate_transforms.geo_reference import Geo_reference

WidtH = 200 # width of boudary in metres

#random.uniform(0,1) #proper implemantation of random generator

def create_mesh(maximum_triangle_area, depth,
                mesh_file=None,
                triangles_in_name = False):
    """
    triangles_in_name, if True is used to append the number of
    triangles in the mesh to the mesh file name.
    """

    WidtH = 200 # width of boudary in metres
    breadth = depth

    print "building footprint"
    print depth * breadth , "m^2"
    block = 625
    BL = block**0.5

    porosity = breadth/BL                               
    print porosity, " Building porosity"
    # create a mesh instance of class Mesh
    m = Mesh()

    # Boundary of problem
    outer_polygon = [[0,0],[5*WidtH,0],[5*WidtH,WidtH],[0,WidtH]]
    m.add_region_from_polygon(outer_polygon, tags={'wall':[0,2], 'wave':[3], 'back':[1]})

    # inner polygons => building boundaries
    
    whs = depth/2 
    lhs = breadth/2 
    Th = (45 *(3.142/180)) # sets an initial rotation      
    #Th = 0
    ForDep = (0.2*WidtH) + (BL-whs)
    RearDep = 1.2*WidtH 
        
    Breadths = Numeric.arrayrange( -(BL/2), WidtH+(BL/2), (BL))
    #Breadths = Numeric.arrayrange( (BL/2), WidtH-(BL/2), (BL)) # For ortho-offset
    print Breadths, "Breadths"
    Depths = Numeric.arrayrange( ForDep, RearDep, BL )
    print Depths, "Depths"

    for i,D in enumerate(Depths):
        #Breadths = Breadths + ((-1)**i)*(BL/2) #Used to offset buildings
        for B in Breadths:
            wh1 = (-whs) * math.cos(Th) + (-lhs) * math.sin(Th)
            lh1 = (-lhs) * math.cos(Th) - (-whs) * math.sin(Th)
            wh2 = (+whs) * math.cos(Th) + (-lhs) * math.sin(Th)
            lh2 = (-lhs) * math.cos(Th) - (+whs) * math.sin(Th)
            wh3 = (+whs) * math.cos(Th) + (+lhs) * math.sin(Th)
            lh3 = (+lhs) * math.cos(Th) - (+whs) * math.sin(Th)
            wh4 = (-whs) * math.cos(Th) + (+lhs) * math.sin(Th)
            lh4 = (+lhs) * math.cos(Th) - (-whs) * math.sin(Th)
            polygon = [[D+wh1,B+lh1],[D+wh2,B+lh2],[D+wh3,B+lh3],[D+wh4,B+lh4]]
            m.add_hole_from_polygon(polygon, tags={'wall':[0,1,2,3]})        
            #Th = Th + (90 *(3.14159/180)) # keeps rotating individual buildings.

    m.generate_mesh(maximum_triangle_area=maximum_triangle_area)
    triangle_count = m.get_triangle_count()
    
    if mesh_file is None:    
        return m, triangle_count
    else:
        if triangles_in_name is True:
            mesh_file = mesh_file[:-4] + '_Orth(45)_D=' + str(depth) + '_' + str(triangle_count) \
                        + mesh_file[-4:]
        m.export_mesh_file(mesh_file)
        return mesh_file, triangle_count

#-------------------------------------------------------------
if __name__ == "__main__":
    _, triangle_count = create_mesh(100,15,mesh_file="test.tsh")
    print "triangle_count",triangle_count