How to set distance to this text?

[Turbe$Z]

function text_render ( ) 
	for i,v in pairs ( messages ) do 
		local x, y, z = unpack ( v ) 
		local sx, sy, _ = getScreenFromWorldPosition ( x, y, z ) 
		if sx then 
			dxDrawText ( i, sx+2, sy+2, sw, sh, tocolor ( 0, 0, 0, 255 ), 2.0, "default-bold" ) 
			dxDrawText ( i, sx, sy, sw, sh, tocolor ( 0, 136, 255, 255 ), 2.0, "default-bold" ) 
		end 
	end 
end
addEventHandler("onClientRender",getRootElement(),text_render) 

i want set max distance for this, but how?  

Edited April 16, 2017 by Turbo777

[IIYAMA]

 

local cameraX, cameraY, cameraZ  = getCameraMatrix ()
for i,v in pairs ( messages ) do 
    local x, y, z = unpack ( v ) 
  	if getDistanceBetweenPoints3D (cameraX, cameraY, cameraZ, x, y, z ) < 100 then
      local sx, sy = getScreenFromWorldPosition ( x, y, z ) 
      if sx then 
          dxDrawText ( i, sx+2, sy+2, sw, sh, tocolor ( 0, 0, 0, 255 ), 2.0, "default-bold" ) 
          dxDrawText ( i, sx, sy, sw, sh, tocolor ( 0, 136, 255, 255 ), 2.0, "default-bold" ) 
      end 
    end
end 

 

 

If you also want to scale the text according to the REAL distance, see: