Simple STMap for Nuke that also supports alpha.

CS_STMap.tcl

set cut_paste_input [stack 0]
version 9.0 v8
CheckerBoard2 {
 inputs 0
 format "1920 1080 0 0 1920 1080 1 HD_1080"
 name CheckerBoard1
 selected true
 xpos -150
 ypos -417
}
Radial {
 output alpha
 area {480 270 1440 810}
 softness 0
 color 0
 name Radial1
 selected true
 xpos -150
 ypos -328
}
Dot {
 name Dot4
 selected true
 xpos -116
 ypos -198
}
Constant {
 inputs 0
 channels rgb
 format "1920 1080 0 0 1920 1080 1 HD_1080"
 name Constant1
 selected true
 xpos -40
 ypos -417
}
Expression {
 expr0 x/width
 expr1 y/height
 expr2 0
 expr3 1
 name Expression1
 selected true
 xpos -40
 ypos -322
}
CornerPin2D {
 to1 {240 270}
 to2 {1440 270}
 to3 {1680 810}
 to4 {480 810}
 invert false
 from1 {0 0}
 from2 {{width} 0}
 from3 {{width} {height}}
 from4 {0 {height}}
 name CornerPin2D1
 selected true
 xpos -40
 ypos -274
}
MergeExpression {
 inputs 2
 temp_name0 xPos
 temp_expr0 Br*input1.width
 temp_name1 yPos
 temp_expr1 Bg*input1.height
 expr0 Ar(xPos,yPos)
 expr1 Ag(xPos,yPos)
 expr2 Ab(xPos,yPos)
 expr3 Aa(xPos,yPos)*Ba
 name MergeExpression1
 selected true
 xpos -40
 ypos -202
}
Premult {
 name Premult1
 selected true
 xpos -40
 ypos -130
}