# rotz

## rotation autour de l´axe des z

Like all linear transformations that command is in 2 modes: direct and matrix.

## rotz obj

### rotz(an) obj(id) [poi(x,y)]

Rotates angle an around z axis with respect to the point (x,y) (its center of gravity by default) the object identifier id

### rotz(an) vertex(s) object(id)

Rotates the vertex s of the object id angle an around the z axis with respect to its center of gravity.
Note:
object is fog, light, traj, var, view, vol.
Examples:
1) rotz(PI/2) poi(100,-20,50) vertex[1,5] vol(1,3): rotates around the z axis the vertices (1,2,3,4,5) of the volumes 1 et 3 angle PI/2 with respect to point (100,-20,50).
2) rotz(PI/2) var("x"): rotates around the z axis the variable x angle PI/2 with respect to its center of gravity.
3) rotz(.1*PI) eye view(2): rotates angle .1*PI around the z axis the eye of the view 2.

### rotz(a1,a2)vol(a)rotz(b1,b2)vol(b)

Varies rotz matrix vol(a) in the interval [a1,a2] when rotz matrix vol(b) varies in the interval [b1,b2].
Can be used for attach the rotz variations of volume a to those of its father b.
Note: rotz(b1,b2) may be any other transformation transf(b1,b2).

## rotz image

### rotz(an)image(id)

Rotates image id angle an with around its center.
Options:
col(r,v,b,t): complete with pixels color (r, g, b, t) (black and transparent by default).
poi(x,y): normalized center of rotation (0.5, 0.5 default).
rotz(an1,an2): vortex.

## rotz matrix

### rotz matrix vol(id)

Returns the z rotation angle of the volume id matrix.
Options:
format(f): modulo f.

### rotz(an)matrix vol(id)

Rotates volume id angle an around the z axis by changing its matrix.
Options:
ini: from the basic transformation.

## roty view

### rotz(an)eye view(id)

Rotates angle an around the z axis the eye of the view id.

### rotz(an)aim view(id)

Rotates angle an around the z axis the aim point of the view id.
Options:
validate(0): from the initial position.