#PH4100 Major Poject - Photometry - Star field simulation program
#Aaron Andrews
#Last edited: 03/10/2016

#This program generates a set number of stars with random positions and max. grey values

import math
import random as rm
import numpy as np
import matplotlib
import matplotlib.pyplot as plt
import matplotlib.image as mpimg

def SimStarField(nxPixel,nyPixel,MaxPixelValue,nStars):
    #Create empty arrays
    Image1=np.zeros((nxPixel,nyPixel)) #array to be output once filled - each cell contains grey values
    PosX=np.zeros(nStars) #x coordinates
    PosY=np.zeros(nStars) #y coordinates
    Peak=np.zeros(nStars) #peak grey value for each star

    #Loop over all stars
    n=0
    while n<nStars:
        #Random value generation (eventually will be replaced with retrieval from database of stars)
        PosX[n]=rm.random()*nxPixel #genaerates random value between 0 and 1, multiplies by relevent range
        PosY[n]=rm.random()*nyPixel
        #MaxGrey[n]=rm.random()*MaxPixelValue
        Image1[int(PosX[n]),int(PosY[n])]=1
        n=n+1
    return Image1
    
    

#Defining variables
ImageX=640 #pixels, x axis
ImageY=480 #pixels, y axis
MaxGrey=65535

Nstars=50 #number of stars to generate

SimStarField(ImageX,ImageY,MaxGrey,Nstars)


    
'''
plt.figure(1)
plt.plot(PosX,PosY,'+')
plt.title('Random generated star positions')
plt.xlabel('X position')
plt.ylabel('Y position')
plt.xlim(0,ImageX)
plt.ylim(0,ImageY)
plt.show(1)'''