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8.2.5.3} Roto-translation transformation

 This directive provides a coordinate transformation, predefined by a ROT--DEFIni
 card, for all bodies embedded between the two lines.

 $Start_transform [ROT-DEFIni name] (or [ROT-DEFIni number])
 ..............
 ..............
 ..............
 $End_transform


 Two nested (signed) transformations R2 and R1 can be used, acting on a
 body vector r as   r'=R2(R1(r)):

 $Start_transform R2
 ...
 $Start_transform R1
 ...
 $End_transform
 ...
 $End_transform

 
Example 1:
....
* Cylindrical target is transformed with transformation "Rotdefi1"
$Start_transform Rotdefi1 RCC targRepl 0.0 0.0 -5.0 0.0 0.0 10.0 5.0 $End_transform ....
* ROT-DEFI transformation: shift of (0,-2,-30) then rotation of -21 degrees
* around the x axis
ROT-DEFI 0.0 -2.0 -30.0Rotdefi1 ROT-DEFI 100. -21. Rotdefi1 Example 2 (with lattice): ....
* Cylindrical target
RCC target 0.0 0.0 -5.0 0.0 0.0 10.0 5.0
* Target replica is transformed with inverse transformation of the lattice
$Start_transform -Rotdefi1 RCC targRepl 0.0 0.0 -5.0 0.0 0.0 10.0 5.0 $End_transform ....
* Regions
TARGET 5 +target REPLICA 5 +targRepl ....
* Lattice
LATTICE REPLICA Rotdefi1 ....
* ROT-DEFI transformations shift of (0,-2,-30) then rotation of -21 degrees
* around the x axis
ROT-DEFI 0.0 -2.0 -30.0Rotdefi1 ROT-DEFI 100. -21. Rotdefi1
Example 3:
ROT-DEFIni 3. -90. 0. 0. 0. 0. XtoZ ........................................ $Start_transform XtoZ $Start_translat 0. -30. +20. $Start_expansion 10. QUA Elipsoid 0.0025 0.04 0.0064 0.0 0.0 0.0 0.055 0.64 0.0256 1.8881 $End_expansion $End_translat $End_transform transforms an ellipsoid centred at (11, 8, -2), with semiaxes 20, 5 and 12.5 cm long parallel to the coordinate axes, to a similar one with semiaxes 200, 50 and 125 cm, centred at (11, -22, 18) and rotated by 90 degrees (axis z becomes axis x).
Example 4:
Trivial example where the combined nested transformation is the identity. The first transformation (ft) is a rotation by 90 deg around the y axis, followed by a shift of 10 cm along the z axis. The second transformation is the inverse: a shift of -10 cm along the z axis and a rotation of -90 deg around the y axis. ROT-DEFI 200. 90. ft ROT-DEFI 0.0 10.ft ROT-DEFI 0.0 -10.st ROT-DEFI 200. -90. st $start_transform st $start_transform ft
* Cylindrical target
RCC target 0.0 0.0 0.0 0.0 0.0 10. 2. $end_transform $end_transform

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