mathr / blog / #

ray42 as a Lua package using tolua

cube of spheres 3D

ray42 was nice as it was, but I got fed up with having to recompile each time I wanted to render a new scene, and C++ isn't a particularly friendly scene description language. So I'm now using tolua to make a Lua package from the core of ray42, and it seems to work ok.

The image above was generated by this code:


local s = nil
for x = -1, 1 do for y = -1, 1 do for z = -1, 1 do
  local m
  if x*y*z == 0 then m = gold else m = cyan end
  local t = sphere3(m, 0.5):translate(v3(x,y,z)*1.5)
  if s ~= nil then s = s + t else s = t end
end end end
s = s:transform(rotate3(0.3,1,2) * rotate3(0.3,0,2) * rotate3(0.3,0,1))

local l = Lights3:new(rgb(0.25,0.25,0.25))
l:add(v3(-3,0,0), rgb(0.5,0.5,0.5))
l:add(v3( 3,0,0), rgb(0.5,0.5,0.5))
l:add(v3(0,-3,0), rgb(0.5,0.5,0.5))
l:add(v3(0, 3,0), rgb(0.5,0.5,0.5))
l:add(v3(0,0,-3), rgb(0.5,0.5,0.5))
l:add(v3(0,0, 3), rgb(0.5,0.5,0.5))

render3(s, l, 788, 576, 4/3, 2)

One small tip when using tolua with recent versions of g++: activate the -Wno-write-strings flag to avoid drowning in a flood of:

warning: deprecated conversion from string constant to 'char*'

It is quite boring writing wrappers for ray42's C++ template classes because tolua doesn't seem to understand templates, maybe I should be using tolua++ or some other tool entirely.