## reb Class REB_TrapShapeEightCurve

```Object
common:Generic
common:TrapShape
reb:REB_TrapShapeEightCurve
```

`class TrapShape:REB_TrapShapeEightCurve`

This shape uses the eight function.

This variant of the function has a signed and absolute value version of the distance. The function also has a complex conjugate and a polar variant. The transformed value is the complex return value of the function.

Ultra Fractal Source
``` class REB_TrapShapeEightCurve(common.ulb:TrapShape) {
; This shape uses the eight function.<br>
; <p>
; This variant of the function has a signed and absolute value
; version of the distance. The function also has a complex conjugate and a
; polar variant. The transformed value is the complex return value of the function.
public:
import "common.ulb"

; Constructor
func REB_TrapShapeEightCurve(Generic pparent)
TrapShape.TrapShape(pparent)
endfunc

; Call this for each iteration being trapped.
float func Iterate(complex pz)
TrapShape.Iterate(pz)
float theta = 0
float d =  0
float rr = 0
theta = atan2(pz)
int sgn = 1
if @sgn
sgn = -1
endif
rr = @a*cos(theta)^(-2)*cos(2*theta)^0.5
if !@ptraps
if @absval
d = abs(cabs(pz) - cabs(rr*cos(theta)+ sgn*flip(rr*sin(theta))))
else
d = cabs(pz - (rr*cos(theta) + sgn*flip(rr*sin(theta))))
endif
m_LastZ = (rr*cos(theta) + sgn*flip(rr*sin(theta)))
else
float x = real(pz)
float y = imag(pz)
if @disttype == 0
d = abs(x-rr*cos(theta) + y-rr*sin(theta))
else
d = (abs(x-rr*cos(theta)) + abs(y-rr*sin(theta)))
endif
m_LastZ = x-rr*cos(theta) + flip(y-rr*sin(theta))
endif
return d
endfunc

default:
title = "Eight Curve"
int param v_trapshapeeightcurve
caption = "Version (Trap Shape Eight Curve)"
default = 101
hint = "This version parameter is used to detect when a change has been made to the formula that is incompatible with the previous version. When that happens, this field will reflect the old version number to alert you to the fact that an alternate rendering is being used."
visible = @v_trapshapeeightcurve < 101
endparam
bool param ptraps
caption = "Use as Polar Traps"
default = false
endparam
param disttype
caption = "Distance type"
default = 0
enum = "Abs total" "Abs parts"
visible = @ptraps
hint = "The distance function must be positive. \
The absolute value can be taken of the \
whole function or of its individual parts."
endparam
float param a
caption = "Polar parameter"
default = 0.2
hint = "Affects spread and scale of trap"
endparam
bool param sgn
caption = "Conjugate transform"
default = false
visible = !@ptraps
endparam
param absval
caption = "Absolute Value"
default = false
visible = !@ptraps
endparam
}
```

Constructor Summary
`REB_TrapShapeEightCurve()`

`REB_TrapShapeEightCurve(Generic pparent)`
Constructor

Method Summary
` float` `Iterate(complex pz)`
Call this for each iteration being trapped.

Methods inherited from class common:TrapShape
`GetColorChannel, GetTextureValue, GetTransformedPoint, Init, IterateSilent, SetThreshold`

Methods inherited from class common:Generic
`GetParent`

Methods inherited from class Object

Constructor Detail

### REB_TrapShapeEightCurve

`public REB_TrapShapeEightCurve(Generic pparent)`
Constructor

### REB_TrapShapeEightCurve

`public REB_TrapShapeEightCurve()`
Method Detail

### Iterate

`public float Iterate(complex pz)`
Call this for each iteration being trapped.

Overrides:
`Iterate` in class `TrapShape`