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 -- The CACHE_GEOMETRY option is also recommended to improve performance.
  14
  15 -- Set the number of frames to be rendered for the animation.
  16 local frames = 360
  17
  18 -- Define the code to calculate where the camera is, in world coordinates.
  19 local eye = function(frame)
  20     -- just rotate around the center of the scene on the XZ plane
  21     local center    = vec_new(0, 0.4, 0)
  22     local distance  = 0.7
  23     local start     = math.pi
  24     local t = start + 2 * math.pi * frame / frames
  25     local v = vec_new(math.cos(t), 0, math.sin(t))
  26     return vec_add(vec_scale(v, distance), center)
  27 end
  28
  29 -- Define the code to calculate where the focal point of the scene is.
  30 local look = function(frame)
  31     -- keep the camera focused at the center
  32     return vec_new(0, 0, 0)
  33 end
  34
  35 -- Define the actual objects of the scene that will be rendered, in the
  36 -- extended u3d format.
  37 local scene = [[
  38 l -14687.0 7986.0 8976.0 1.0 1.0 1.0
  39 g checker.obj
  40 c 1.0 0.6 0.6 0.6
  41 m checker.ppm
  42 r -1.57 1.0 0.0 0.0
  43 p 1.0 1.0 1.0 100.0
  44 g teapot.raw
  45 c 0.9 0.7 0.1 0.2
  46 p 1.0 1.0 1.0 60.0
  47 t 0.0 0.1 0.0
  48 s 0.004 0.004 0.004
  49 ]]
  50
  51 -- Set the number of samples for supersampling.  If this is set to a value
  52 -- of two or greater, each frame will be rendered larger by the factor
  53 -- specified.  ImageMagick is used to scale the frames back down to size;
  54 -- if ImageMagick is not installed, this script will exit with error 1.
  55 local supersample = 2
  56
  57 -- Set the width and height of the viewport.
  58 local size = {w = 640, h = 480}
  59
  60 -- Set the number of concurrent renderings (for multi-core machines).
  61 local jobs = 6
  62
  63 -- Set the options to be passed directly to ffmpeg.
  64 local ffmpeg_opts = "-b 1024k"
  65
  66 -- end of configuration
  67 ---------------------------------------------------------------------------
  68
  69 function vec_new(x, y, z)
  70     return {x = x, y = y, z = z}
  71 end
  72
  73 function vec_add(a, b)
  74     return vec_new(a.x + b.x, a.y + b.y, a.z + b.z)
  75 end
  76
  77 function vec_scale(v, s)
  78     return vec_new(v.x * s, v.y * s, v.z * s)
  79 end
  80
  81 local fmt   = string.format
  82 local write = function(...) io.write(fmt(...)) io.flush() end
  83 local run   = function(...) return os.execute(fmt(...)) end
  84
  85 function render(i)
  86     while i do
  87         local w, h = size.w, size.h
  88         if 1 < supersample then
  89             w = w * supersample
  90             h = h * supersample
  91         end
  92         local filename  = fmt("frames/anim%04d.bmp", i)
  93         local command   = fmt("./rasterize -o %s >/dev/null", filename)
  94         local out = io.popen(command, "w")
  95         local e = eye(i)
  96         local l = look(i)
  97         write("\27[80D\27[2Kframe\t %4d / %d", i, frames)
  98         out:write(fmt([[
  99 U4
 100 %d %d
 101 %f %f %f
 102 %f %f %f
 103 0 1 0
 104 1.57 %f 0.1 1000
 105 1.0 1.0 1.0
 106 %s
 107 X
 108 ]], w, h, e.x, e.y, e.z, l.x, l.y, l.z, size.w/size.h, scene))
 109         i = coroutine.yield()
 110         out:close()
 111         if 1 < supersample and
 112                 run("convert %s -scale %dx%d %s", filename, size.w, size.h, filename) ~= 0 then
 113             print()
 114             os.exit(1)
 115         end
 116     end
 117 end
 118
 119 function renderings()
 120     local t = {}
 121     for i = 1,jobs do
 122         table.insert(t, coroutine.wrap(render))
 123     end
 124     local iterations = frames + jobs
 125     local frame = 0
 126     return function()
 127         frame = frame + 1
 128         if frame <= iterations then
 129             local i = frame
 130             if frames < i then i = null end
 131             return t[1 + frame % jobs], i
 132         end
 133     end
 134 end
 135
 136 print("Animating scene...")
 137
 138 run("rm -rf frames && mkdir frames >/dev/null 2>&1")
 139 for render,frame in renderings() do render(frame) end
 140
 141 print()
 142
 143 if run("ffmpeg -i frames/anim%%04d.bmp %s -y -an scene.avi", ffmpeg_opts) == 0 then
 144     print("Animation written to scene.avi.")
 145 else
 146     print("The animation could not be created. Is ffmpeg installed?")
 147     os.exit(2)
 148 end
 149