Dogcows Code - chaz/rasterize/blob - animate.lua

   1 #!/usr/bin/env lua
   2
   3 --
   4 -- CS5600 University of Utah
   5 -- Charles McGarvey
   6 -- mcgarvey@eng.utah.edu
   7 --
   8
   9 -- This program automates the process of creating simple fly-by animations.
  10 -- The rasters are saved in the `frames' directory, and if ffmpeg is
  11 -- installed, the frames will also be combined into a video file.  This script
  12 -- must be called from the same directory where the rasterize program is.
  13
  14 -- Set the number of frames to be rendered for the animation.
  15 local frames = 360
  16
  17 -- Define the code to calculate where the camera is, in world coordinates.
  18 local eye = function(frame)
  19     -- just rotate around the center of the scene on the XZ plane
  20     local center    = vec_new(0, 1, 0)
  21     local distance  = 4
  22     local start     = math.pi
  23     local t = start + 2 * math.pi * frame / frames
  24     local v = vec_new(math.cos(t), 0, math.sin(t))
  25     return vec_add(vec_scale(v, distance), center)
  26 end
  27
  28 -- Define the code to calculate where the focal point of the scene is.
  29 local look = function(frame)
  30     -- keep the camera focused on the buddha
  31     return vec_new(2, 1, 2)
  32 end
  33
  34 -- Define the actual objects of the scene that will be rendered, in the
  35 -- extended u3d format.
  36 local scene = [[
  37 L 0 1000000 0 1 1 1 1 1 1
  38 L 0 0 1000000 1 1 1 1 1 1
  39 g ak47.obj
  40 c 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1
  41 M 0.9 0.9 0.9 128
  42 g dragon.raw
  43 M 0.3 0.3 0.3 5
  44 c 0.7 0.3 0.2 0.8 0.2 0.1 0.9 0.2 0.2
  45 t -2 -1 -2
  46 s 2 2 2
  47 g budda.raw
  48 c 0.1 0.2 0.7 0.1 0.3 0.9 0.2 0.1 0.8
  49 t 2 -1.5 2
  50 s 10 10 10
  51 g bunny.raw
  52 M 0.2 0.2 0.2 1
  53 c 0.9 0.8 0.9 0.8 0.7 0.9 0.9 0.8 0.7
  54 t -2 -1 2
  55 s 10 10 10
  56 ]]
  57
  58 -- Set the number of samples for supersampling.  If this is set to a value of
  59 -- two or greater, each frame will be rendered larger by the factor specified.
  60 -- ImageMagick is used to scale the frames back down to size; if ImageMagick
  61 -- is not installed, the resulting frames will end up bigger than they should
  62 -- be and the aliasing problem will not be fixed.
  63 local supersample = 4
  64
  65 -- Set the width and height of the viewport.
  66 local size = {w = 640, h = 480}
  67
  68 -- Set the number of concurrent renderings (for multi-core machines).
  69 local jobs = 6
  70
  71
  72 -- end of configuration
  73 ---------------------------------------------------------------------------
  74
  75 local fmt   = string.format
  76 local write = function(...) return io.write(fmt(...)) end
  77 local run   = function(...) return os.execute(fmt(...)) end
  78
  79 function vec_new(x, y, z)
  80     return {x = x, y = y, z = z}
  81 end
  82
  83 function vec_add(a, b)
  84     return vec_new(a.x + b.x, a.y + b.y, a.z + b.z)
  85 end
  86
  87 function vec_scale(v, s)
  88     return vec_new(v.x * s, v.y * s, v.z * s)
  89 end
  90
  91 function render(i)
  92     while i do
  93         local w, h = size.w, size.h
  94         if 1 < supersample then
  95             w = w * supersample
  96             h = h * supersample
  97         end
  98         local filename  = fmt("frames/anim%04d.bmp", i)
  99         local command   = fmt("./rasterize -o %s >/dev/null", filename)
 100         local out = io.popen(command, "w")
 101         local e = eye(i)
 102         local l = look(i)
 103         write("\27[80D\27[2Kframe\t %4d / %d", i + 1, frames)
 104         out:write(fmt([[
 105 U3
 106 %d %d
 107 %f %f %f
 108 %f %f %f
 109 0 1 0
 110 1.57 %f 0.1 1000
 111 %s
 112 X
 113 ]], w, h, e.x, e.y, e.z, l.x, l.y, l.z, size.w/size.h, scene))
 114         i = coroutine.yield()
 115         out:close()
 116         if 1 < supersample then
 117             run("convert %s -scale %dx%d %s", filename, size.w, size.h, filename)
 118         end
 119     end
 120 end
 121
 122 print("Animating scene...")
 123
 124 local threads = {}
 125 for i = 1,jobs do
 126     table.insert(threads, coroutine.wrap(render))
 127 end
 128
 129 run("rm -rf frames && mkdir frames >/dev/null 2>&1")
 130 for i = 0,(frames-1) do
 131     threads[1 + (i % jobs)](i)
 132 end
 133 for _,thread in ipairs(threads) do thread(null) end
 134 print()
 135
 136 if run("ffmpeg -i frames/anim%04d.bmp -b 1024k -y -an scene.avi") == 0 then
 137     print("Animation written to scene.avi.")
 138 end
 139