Create colorful tregenza sky patches.

tregenza.py

# coding=utf-8
import os
import random
import glob


def renderTregenzaPatches(outputPath='tregenzaPatch.hdr',imgResolution=200,reinhartMF=1,cleanUp=True):
    """
    :param outputPath: A filepath where the created image should be written to. Defaults to tregenzaPatch.hdr in the same
        directory that the script is being run in.
    :param imgResolution: Resolution of the generated fish eye image. Defaults to 200 pixels.
    :param reinhartMF: Sky resolution. Specify a value between 1 to 6. In Windows, only 1 is likely to work.
    :param cleanUp: Set this to True to delete all the files that were created during the process.
    :return:
    """

    viewDefinition="-vth -x {res} -y {res} -vd 0 0 1 -vv 180 -vh 180 -vp 0 0 0 -vu 0 -1 0".format(res=imgResolution)

    skyGlow="""
    #@rfluxmtx u=+Y h=u
    void glow groundglow 0 0 4 1 1 1 0
    groundglow source ground 0 0 4 0 0 -1 180
    
    #@rfluxmtx u=+Y h=r{MF} 
    void glow skyglow 0 0 4 1 1 1 0
    skyglow source skydome 0 0 4 0 0 1 180
    """.format(MF=reinhartMF)

    
    with open('skyDome.rad','w') as skyDome:
        skyDome.write(skyGlow)

    cmd = """vwrays -ff {view}  | rfluxmtx -ffc -n 16 -x {res} -y {res} -ld- -ab 1  -o skyTregenza%04d.hdr - skyDome.rad"""\
        .format(view=viewDefinition,res=imgResolution)

    os.system(cmd)
    cleanUpList = ['skyDome.rad']



    Patches=144*reinhartMF*reinhartMF+1+1

    genskyvecHeader=["#?RADIANCE"]
    genskyvecHeader.append("genskyvec -m %s"%reinhartMF)
    genskyvecHeader.append("NROWS=%s"%Patches)
    genskyvecHeader.append("NCOLS=1")
    genskyvecHeader.append("NCOMP=3")
    genskyvecHeader.append("FORMAT=ascii\n")
    genskyvecHeader.append("\n")
    genskyvecHeader="\n".join(genskyvecHeader)

    for val in xrange(Patches):
        genskyvecHeader+="%.8f\t%.8f\t%.8f\n"%(random.random(),random.random(),random.random())


    with open('sky.vec','wb') as skyVec:
        skyVec.write(genskyvecHeader)


    os.system('dctimestep skyTregenza%04d.hdr sky.vec > {}'.format(outputPath))

    cleanUpList.append('sky.vec')
    cleanUpList.extend(glob.glob("skyTregenza*.hdr"))

    if cleanUp:
        for files in cleanUpList:
            os.remove(files)

    return outputPath

renderTregenzaPatches('tregenzaPatches.hdr',imgResolution=600)