// Persistence of Vision Ray Tracer Scene Description File
// File: AM_Resize.inc
// Vers: 3.8
// Desc: http://news.povray.org/povray.newusers/thread/%3C60c8e000%241%40news.povray.org%3E/
// Date: 15 June 2021
// Auth: Alain Martel, to Herbert Pflaum
//       Thomas de Groot made a macro out of this.

//=======================================================================================================
#macro Resize (Obj, Center, DimFactor)
// 1) Obj is your object.

// 2) Find it's bounds :
#local TopRight   = max_extent(Obj);
#local BottomLeft = min_extent(Obj);

// 3) Find the centre of the object :
#local ObjCentre = (TopRight + BottomLeft )/2;

// 4) Place your object at the origin. Center "on" places the the 'center' of the object at the origin;
//    with Center "off", the 'base' of the object is placed at the origin :
#if (Center)
  #local Obj = object {Obj translate -ObjCentre }
#else
  #local Obj = object {Obj translate <-ObjCentre.x, BottomLeft.y, -ObjCentre.z> }
#end

// 5) Optionally, you can scale it to fit and prevent clipping :
#local Extent = max(TopRight.x, TopRight.y, TopRight.z);
// Find the largest dimension

// Standardize the dimension  to your needs. DimFactor=1 effectively scales your object down to a size of 1 unit;
// other values scales the object up or down :
#declare Obj = object {Obj scale DimFactor/Extent}

// 6) Finally, place the object in your scene : 

Obj

#end  //of macro

//=======================================================================================================

/*
Usage example in a scene: 
-------------------------

1) Include the macro:

#include "AM_Resize to standard.inc"


2) Apply the macro to your object (example with "the Bunny"):

#include "bunny_POV_geom.inc"
#declare Bunny =
object {bunny_
  rotate 180*y
}

object {
  Resize (Bunny, off, 1)  //resizing the object to 1 pov-unit
  rotate 10*y
  translate -0.5*z
  translate 1.0*x
}

*/