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 = 2
  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 -- Set the options to be passed directly to ffmpeg.
  72 local ffmpeg_opts = "-b 1024k"
  73
  74 -- end of configuration
  75 ---------------------------------------------------------------------------
  76
  77 function vec_new(x, y, z)
  78     return {x = x, y = y, z = z}
  79 end
  80
  81 function vec_add(a, b)
  82     return vec_new(a.x + b.x, a.y + b.y, a.z + b.z)
  83 end
  84
  85 function vec_scale(v, s)
  86     return vec_new(v.x * s, v.y * s, v.z * s)
  87 end
  88
  89 local fmt   = string.format
  90 local write = function(...) io.write(fmt(...)) io.flush() end
  91 local run   = function(...) return os.execute(fmt(...)) end
  92
  93 function render(i)
  94     while i do
  95         local w, h = size.w, size.h
  96         if 1 < supersample then
  97             w = w * supersample
  98             h = h * supersample
  99         end
 100         local filename  = fmt("frames/anim%04d.bmp", i)
 101         local command   = fmt("./rasterize -o %s >/dev/null", filename)
 102         local out = io.popen(command, "w")
 103         local e = eye(i)
 104         local l = look(i)
 105         write("\27[80D\27[2Kframe\t %4d / %d", i, frames)
 106         out:write(fmt([[
 107 U3
 108 %d %d
 109 %f %f %f
 110 %f %f %f
 111 0 1 0
 112 1.57 %f 0.1 1000
 113 %s
 114 X
 115 ]], w, h, e.x, e.y, e.z, l.x, l.y, l.z, size.w/size.h, scene))
 116         i = coroutine.yield()
 117         out:close()
 118         if 1 < supersample then
 119             run("convert %s -scale %dx%d %s", filename, size.w, size.h, filename)
 120         end
 121     end
 122 end
 123
 124 function renderings()
 125     local t = {}
 126     for i = 1,jobs do
 127         table.insert(t, coroutine.wrap(render))
 128     end
 129     local iterations = frames + jobs
 130     local frame = 0
 131     return function()
 132         frame = frame + 1
 133         if frame <= iterations then
 134             local i = frame
 135             if frames < i then i = null end
 136             return t[1 + frame % jobs], i
 137         end
 138     end
 139 end
 140
 141 print("Animating scene...")
 142
 143 run("rm -rf frames && mkdir frames >/dev/null 2>&1")
 144 for render,frame in renderings() do render(frame) end
 145
 146 print()
 147
 148 if run("ffmpeg -i frames/anim%%04d.bmp %s -y -an scene.avi", ffmpeg_opts) == 0 then
 149     print("Animation written to scene.avi.")
 150 end
 151