def main():
comm = MPI.COMM_WORLD
id= comm.Get_rank()
wsize= comm.Get_size()
tstart = MPI.Wtime()
fsky = open("skymap.png","r")
reader = Reader(fsky)
skypixelwidth, skypixelheight, skypixels, metadata=reader.read_flat()
pixelwidth = int(argv[1])
pixelheight = int(argv[2])
tskymapstart = MPI.Wtime()
telepixels = np.zeros((pixelwidth*pixelheight*3),dtype=np.uint8)
colorpixels = np.zeros((pixelwidth*pixelheight),dtype=np.uint8)
skystartall = np.zeros((pixelwidth*pixelheight),dtype=np.uint32)
telestartall = np.zeros((pixelwidth*pixelheight),dtype=np.uint32)
colorall = np.zeros((pixelwidth*pixelheight),dtype=np.uint8)
totnstepsall=np.zeros((wsize),dtype=np.uint32)
tskymapend = MPI.Wtime()
tskymap = tskymapend-tskymapstart
tmin = 1.e6
tpercparmin=1.e6
hinit=1.e-1
#h=1.e-4
Router = 1000.
Rplane = 700.
Rs = 2.
every = 1
deltalamb = 1.e-1
imagewidth = 50;
imageheight = 50;
tiny = 1.e-30
epsilon=1.e-8
eccentricity = 0.2
Rfac = 1.+1.e-10
heps = 1.e-14
semilatusr = 10.0
tstartpp=MPI.Wtime() #percent parallelized
numperprocess = pixelheight*pixelwidth/wsize
skystart=np.zeros((numperprocess),dtype=np.int32)
telestart=np.zeros((numperprocess),dtype=np.int32)
color = np.zeros((numperprocess),dtype=np.int8)
totnsteps=np.zeros((numperprocess),dtype=np.int32)
trk4all=np.zeros((numperprocess),dtype=np.float)
ttelestop = MPI.Wtime()
ttele = ttelestop-tstartpp
trk4=float("inf")
for index in range(numperprocess):
ypix = int((id*numperprocess+index)/pixelwidth)
xpix = (id*numperprocess+index)%pixelwidth
tstartrk4=MPI.Wtime()
totnsteps[index],skystart[index],telestart[index],color[index]=integrateNullGeodesic(xpix, ypix, pixelheight,pixelwidth, skypixelheight,skypixelwidth,imagewidth,imageheight,Rs,Router,Rplane,eccentricity, semilatusr, epsilon, tiny, hinit,Rfac,heps)
tendrk4=MPI.Wtime()
trk4=min(trk4,(tendrk4-tstartrk4)/float(totnsteps[index]))
totnstepsmax=max(totnsteps)
tstoppp = MPI.Wtime()
tpercpar=tstoppp-tstartpp
comm.Barrier()
if id==0:
totnstepsmaxall=0
else:
totnstepsmaxall=None
comm.Barrier()
totnstepsmaxall=comm.reduce(totnstepsmax,op=MPI.MAX,root=0)
tskymapall = comm.reduce(tskymap, op=MPI.MAX, root=0)
tteleall = comm.reduce(ttele,op=MPI.MAX,root=0)
comm.Gatherv(skystart,skystartall,root=0)
comm.Gatherv(telestart, telestartall, root=0)
comm.Gatherv(color,colorall, root=0)
trk4min=comm.reduce(trk4,op=MPI.MIN,root=0)
comm.Barrier()
tend = MPI.Wtime()
tall = tend-tstart
if id==0:
tindexstart = MPI.Wtime()
for index in range(pixelheight*pixelwidth):
if(colorall[index]==1):
telepixels[telestartall[index]:telestartall[index]+3]=skypixels[skystartall[index]:skystartall[index]+3]
else:
telepixels[telestartall[index]]=255 #leave other two indices zero,red
tindexend = MPI.Wtime()
tindex = tindexend-tindexstart
if id==0:
twritestart = MPI.Wtime()
ftele = open('teleview_{pw}_{ph}_{ws}.png'.format(pw=pixelwidth,ph=pixelheight,ws=wsize), "w")
telewrite=Writer(width=pixelwidth,height=pixelheight,greyscale=False,alpha=False)
telewrite.write_array(ftele,telepixels)
ftele.close()
twriteend=MPI.Wtime()
twrite = twriteend-twritestart
fsky.close()
comm.Barrier()
tmax = comm.reduce(tall,MPI.MAX,root=0)
tpercparmin = comm.reduce(tpercpar/tall,op=MPI.MIN,root=0)
comm.Barrier()
if (id==0):
# print("Telescope dimensions in M", 2.*imagewidth, 2.*imageheight)
# print("Telescope resolution", pixelwidth, pixelheight)
# print("Skymap resolution", skypixelwidth, skypixelheight)
# print("Schwarzschild radius in M", 2.*Rs)
# print("Outer radius in M", 2.*Router)
# print("Telescope radius in M", 2.*Rplane)
# print("Number of processes = ",wsize)
# print("Maximum number of integration steps taken is",totnstepsmaxall)
# print("The time for a single step of the RK4 is",trk4min)
# print("Total runtime = ",tmax)
# print("Fraction parallel = ", tpercparmin)
print pixelwidth,pixelheight,wsize,totnstepsmaxall,trk4min,tmax,tpercparmin, tindex, twrite, tskymapall, tteleall
MPI.Finalize()
