Performance Optimizations

Every developer who creates real-time applications that use three-dimensional (3-D) graphics is concerned about performance optimization. This section provides you with guidelines about getting the best performance from your scene. 

• Keep the textures small. 
• Only set needed textures in material
• D3D Effect (Shader Text) heavy debase performance, especially work with multi-texture. Only use shader when really needed (if possible, instead of it by checking object's styles like Alpha Test, Alpha Blend, Color Add...); if a material include shader text, assign it to objects as less as possible.
• Check material's No Receive Shadow option for unneeded object like sky.
• Check Exclusive VB style for meshs. This feature use more video memory but can speed up rendering, especially for massive vertices objects.
• For scripting, keep the " .new() " invocation out of loop as possible, because the ".new()" function is slow. If a function's return value is a class (e.g. vec, color, rect, etc), it will call ".new()" inner. See example code:
  
  local starttime=os.clock()
  
  for i=0,9999 do
  local v1=vec.new(1,2,3)
  local v2=vec.new(5,6,7)
  local v=v1+v2 -- most operator function also has a inner .new() call
  end
  
  print(os.clock()-starttime) -- approximately 1
  
  
  local starttime=os.clock()
  
  local v1=vec.new(1,2,3)
  local v2=vec.new(5,6,7)
  local v=vec.new()
  
  for i=0,9999 do
  v.x=v1.x+v2.x
  v.y=v1.y+v2.y
  v.z=v1.z+v2.z
  end
  
  print(os.clock()-starttime) -- approximately 0.01