--First stop time
celestia:settimescale(0)

--Then get variables containing Mars, the observer and the Celestia co-ord->km conversion factors
mars = celestia:find("Mars")
obs = celestia:getobserver()
km_per_mly=9466411.842
mly_per_km=1.0 / km_per_mly

--Clear render flags & labels
celestia:hide("orbits", "constellations", "boundaries", "markers", "grid")
celestia:hidelabel("planets", "moons", "spacecraft", "asteroids", "comets", "constellations", "stars", "galaxies", "locations")

--Preload Mars textures
mars:preloadtexture()

--Create arrays with the TASC generated MEX locations for each image
names = {
          "10-113_14.28.18_VMC_Img_No_1.png",
          "10-113_14.29.06_VMC_Img_No_2.png",
          "10-113_14.29.50_VMC_Img_No_3.png",
          "10-113_14.30.34_VMC_Img_No_4.png",
          "10-113_14.31.18_VMC_Img_No_5.png",
          "10-113_14.32.02_VMC_Img_No_6.png",
          "10-113_14.32.46_VMC_Img_No_7.png",
          "10-113_14.33.30_VMC_Img_No_8.png",
          "10-113_14.34.14_VMC_Img_No_9.png",
          "10-113_14.34.58_VMC_Img_No_10.png",
          "10-113_14.35.42_VMC_Img_No_11.png",
          "10-113_14.36.26_VMC_Img_No_12.png",
          "10-113_14.37.10_VMC_Img_No_13.png",
          "10-113_14.37.53_VMC_Img_No_14.png",
          "10-113_14.38.37_VMC_Img_No_15.png",
          "10-113_14.39.21_VMC_Img_No_16.png",
          "10-113_14.40.05_VMC_Img_No_17.png",
          "10-113_14.40.49_VMC_Img_No_18.png",
          "10-113_14.41.33_VMC_Img_No_19.png",
          "10-113_14.42.17_VMC_Img_No_20.png",
          "10-113_14.43.01_VMC_Img_No_21.png",
          "10-113_14.43.45_VMC_Img_No_22.png",
          "10-113_14.44.29_VMC_Img_No_23.png",
          "10-113_14.45.13_VMC_Img_No_24.png",
          "10-113_14.45.57_VMC_Img_No_25.png",
          "10-113_14.46.41_VMC_Img_No_26.png",
          "10-113_14.47.25_VMC_Img_No_27.png",
          "10-113_14.48.08_VMC_Img_No_28.png",
          "10-113_14.48.52_VMC_Img_No_29.png",
          "10-113_14.49.36_VMC_Img_No_30.png",
          "10-113_14.50.20_VMC_Img_No_31.png",
          "10-113_14.51.04_VMC_Img_No_32.png",
          "10-113_14.51.48_VMC_Img_No_33.png",
          "10-113_14.52.32_VMC_Img_No_34.png",
          "10-113_14.53.16_VMC_Img_No_35.png",
          "10-113_14.54.00_VMC_Img_No_36.png",
          "10-113_14.54.44_VMC_Img_No_37.png",
          "10-113_14.55.28_VMC_Img_No_38.png",
          "10-113_14.56.12_VMC_Img_No_39.png",
          "10-113_14.56.56_VMC_Img_No_40.png",
          "10-113_14.57.39_VMC_Img_No_41.png",
          "10-113_14.58.22_VMC_Img_No_42.png",
          "10-113_14.59.07_VMC_Img_No_43.png",
          "10-113_14.59.51_VMC_Img_No_44.png",
          "10-113_15.00.35_VMC_Img_No_45.png",
          "10-113_15.01.19_VMC_Img_No_46.png",
          "10-113_15.02.03_VMC_Img_No_47.png",
          "10-113_15.02.46_VMC_Img_No_48.png",
          "10-113_15.03.31_VMC_Img_No_49.png",
          "10-113_15.04.14_VMC_Img_No_50.png",
          "10-113_15.04.59_VMC_Img_No_51.png",
          "10-113_15.05.42_VMC_Img_No_52.png",
          "10-113_15.06.27_VMC_Img_No_53.png",
          "10-113_15.07.10_VMC_Img_No_54.png",
          "10-113_15.07.54_VMC_Img_No_55.png",
        }

dates = {
          celestia:utctotdb(2010, 04, 23, 14, 28, 18),
          celestia:utctotdb(2010, 04, 23, 14, 29, 06),
          celestia:utctotdb(2010, 04, 23, 14, 29, 50),
          celestia:utctotdb(2010, 04, 23, 14, 30, 34),
          celestia:utctotdb(2010, 04, 23, 14, 31, 18),
          celestia:utctotdb(2010, 04, 23, 14, 32, 02),
          celestia:utctotdb(2010, 04, 23, 14, 32, 46),
          celestia:utctotdb(2010, 04, 23, 14, 33, 30),
          celestia:utctotdb(2010, 04, 23, 14, 34, 14),
          celestia:utctotdb(2010, 04, 23, 14, 34, 58),
          celestia:utctotdb(2010, 04, 23, 14, 35, 42),
          celestia:utctotdb(2010, 04, 23, 14, 36, 26),
          celestia:utctotdb(2010, 04, 23, 14, 37, 10),
          celestia:utctotdb(2010, 04, 23, 14, 37, 53),
          celestia:utctotdb(2010, 04, 23, 14, 38, 37),
          celestia:utctotdb(2010, 04, 23, 14, 39, 21),
          celestia:utctotdb(2010, 04, 23, 14, 40, 05),
          celestia:utctotdb(2010, 04, 23, 14, 40, 49),
          celestia:utctotdb(2010, 04, 23, 14, 41, 33),
          celestia:utctotdb(2010, 04, 23, 14, 42, 17),
          celestia:utctotdb(2010, 04, 23, 14, 43, 01),
          celestia:utctotdb(2010, 04, 23, 14, 43, 45),
          celestia:utctotdb(2010, 04, 23, 14, 44, 29),
          celestia:utctotdb(2010, 04, 23, 14, 45, 13),
          celestia:utctotdb(2010, 04, 23, 14, 45, 57),
          celestia:utctotdb(2010, 04, 23, 14, 46, 41),
          celestia:utctotdb(2010, 04, 23, 14, 47, 25),
          celestia:utctotdb(2010, 04, 23, 14, 48, 08),
          celestia:utctotdb(2010, 04, 23, 14, 48, 52),
          celestia:utctotdb(2010, 04, 23, 14, 49, 36),
          celestia:utctotdb(2010, 04, 23, 14, 50, 20),
          celestia:utctotdb(2010, 04, 23, 14, 51, 04),
          celestia:utctotdb(2010, 04, 23, 14, 51, 48),
          celestia:utctotdb(2010, 04, 23, 14, 52, 32),
          celestia:utctotdb(2010, 04, 23, 14, 53, 16),
          celestia:utctotdb(2010, 04, 23, 14, 54, 00),
          celestia:utctotdb(2010, 04, 23, 14, 54, 44),
          celestia:utctotdb(2010, 04, 23, 14, 55, 28),
          celestia:utctotdb(2010, 04, 23, 14, 56, 12),
          celestia:utctotdb(2010, 04, 23, 14, 56, 56),
          celestia:utctotdb(2010, 04, 23, 14, 57, 39),
          celestia:utctotdb(2010, 04, 23, 14, 58, 22),
          celestia:utctotdb(2010, 04, 23, 14, 59, 07),
          celestia:utctotdb(2010, 04, 23, 14, 59, 51),
          celestia:utctotdb(2010, 04, 23, 15, 00, 35),
          celestia:utctotdb(2010, 04, 23, 15, 01, 19),
          celestia:utctotdb(2010, 04, 23, 15, 02, 03),
          celestia:utctotdb(2010, 04, 23, 15, 02, 46),
          celestia:utctotdb(2010, 04, 23, 15, 03, 31),
          celestia:utctotdb(2010, 04, 23, 15, 04, 14),
          celestia:utctotdb(2010, 04, 23, 15, 04, 59),
          celestia:utctotdb(2010, 04, 23, 15, 05, 42),
          celestia:utctotdb(2010, 04, 23, 15, 06, 27),
          celestia:utctotdb(2010, 04, 23, 15, 07, 10),
          celestia:utctotdb(2010, 04, 23, 15, 07, 54),
        }

 xarr = {
          -656.975,
          -681.779,
          -704.491,
          -727.179,
          -749.842,
          -772.479,
          -795.089,
          -817.671,
          -840.225,
          -862.749,
          -885.242,
          -907.704,
          -930.134,
          -952.022,
          -974.384,
          -996.712,
          -1019.004,
          -1041.258,
          -1063.474,
          -1085.651,
          -1107.789,
          -1129.885,
          -1151.938,
          -1173.949,
          -1195.916,
          -1217.837,
          -1239.712,
          -1261.044,
          -1282.824,
          -1304.555,
          -1326.235,
          -1347.863,
          -1369.438,
          -1390.960,
          -1412.426,
          -1433.836,
          -1455.188,
          -1476.481,
          -1497.714,
          -1518.887,
          -1539.517,
          -1560.087,
          -1581.547,
          -1602.463,
          -1623.312,
          -1644.092,
          -1664.801,
          -1684.971,
          -1706.004,
          -1726.030,
          -1746.910,
          -1766.786,
          -1787.506,
          -1807.227,
          -1827.326,
        }

 zarr = {
          9995.963,
          9948.493,
          9904.623,
          9860.413,
          9815.862,
          9770.97,
          9725.74,
          9680.169,
          9634.26,
          9588.011,
          9541.424,
          9494.498,
          9447.235,
          9400.719,
          9352.787,
          9304.519,
          9255.913,
          9206.971,
          9157.692,
          9108.077,
          9058.126,
          9007.839,
          8957.217,
          8906.259,
          8854.967,
          8803.34,
          8751.379,
          8700.276,
          8647.654,
          8594.699,
          8541.41,
          8487.788,
          8433.834,
          8379.547,
          8324.928,
          8269.977,
          8214.694,
          8159.079,
          8103.134,
          8046.857,
          7991.541,
          7935.908,
          7877.351,
          7819.762,
          7761.843,
          7703.595,
          7645.019,
          7587.456,
          7526.88,
          7468.677,
          7407.431,
          7348.588,
          7286.674,
          7227.192,
          7166.005,
        }

 yarr = {
          -8961.556,
          -8986.961,
          -9009.927,
          -9032.583,
          -9054.928,
          -9076.958,
          -9098.672,
          -9120.069,
          -9141.146,
          -9161.902,
          -9182.334,
          -9202.440,
          -9222.218,
          -9241.228,
          -9260.352,
          -9279.142,
          -9297.595,
          -9315.711,
          -9333.485,
          -9350.917,
          -9368.004,
          -9384.744,
          -9401.133,
          -9417.172,
          -9432.855,
          -9448.182,
          -9463.151,
          -9477.429,
          -9491.681,
          -9505.565,
          -9519.082,
          -9532.226,
          -9544.997,
          -9557.392,
          -9569.407,
          -9581.040,
          -9592.290,
          -9603.151,
          -9613.623,
          -9623.703,
          -9633.171,
          -9642.259,
          -9651.359,
          -9659.848,
          -9667.930,
          -9675.603,
          -9682.862,
          -9689.554,
          -9696.128,
          -9701.998,
          -9707.705,
          -9712.740,
          -9717.567,
          -9721.753,
          -9725.604,
        }

obsno = 55
obstring = "23 April 2010"

--Set the initial time
celestia:settime(dates[1]);

--Go to Mars then write title
obs:track(mars)
celestia:flash("European Space Agency\nMars Express Visual Monitoring Camera\nObservation "..obstring, 15)
obs:goto(mars,5)
obs:goto((mars:getposition() + celestia:newvector(xarr[1], yarr[1], zarr[1]) * (mly_per_km)),5)
wait(10)
celestia:flash("Press 'M' for next image, 'N' for previous image.\nUse left and right arrow keys to rotate the\nplanet to the same orientation as the image.", 10)
wait(10)
celestia:showlabel("locations", "moons", "spacecraft")

--Create a function that goes to a given image number
gotoimage = function(imgno)
	
	celestia:settime(dates[imgno])
		
	obs:setposition(mars:getposition() + celestia:newvector(xarr[imgno], yarr[imgno], zarr[imgno]) * (mly_per_km))
		
	celestia:select(mars)
	
	obs:track(mars)
	
	celestia:flash(names[imgno], 60)	

end

--Create a function that will go to the next image in the series
next = function(goto)

	if (count + 1)>obsno then
		count = 1
	else
		count = count + 1
	end
	
	gotoimage(count)
end

--Create a function that will go to the previous image in the series
last = function()
	
	if (count - 1)<1 then
		count = obsno
	else
		count = count - 1
	end
  
    gotoimage(count)
end

--Create a counter holding the position of the current image
count = 1

--Set the position to the first image
gotoimage(count)

--Add the necessary keyboard callback code
keymap = { n = last, m = next }

celestia_keyboard_callback = function(key) 
     f = keymap[key]
     if f then 
        f() 
        return true
     end
        return false
end

celestia:requestkeyboard(true)
repeat
     wait(10)
until false