REM Created in CorelPhotoPaint Version 9.439
REM Created On Saturday, February, 12, 2000 by Alex Link
REM With special thanks for the insights and improvements from
REM Alex Vakulenko.
' 	spinfill9.csc  - a mask rotater script
' The script requires only an active mask but no masks saved to channel.
' The center of the screen is always the center of rotation.
' The center of the mask must be on the right-half of the screen for 
' correct operation of the script.
' Use guidelines with rulers on for precision mask placement.
' Use the Channels Docker to access more than 20 masks.

WITHOBJECT "CorelPhotoPaint.Automation.9"
	csw& = .GetDocumentWidth()
	csh& = .GetDocumentHeight()
	CONST pi# = 3.1415926536
	FUNCTION ATAN2(y#, x#)	' Thank you for this gem, Alex
		IF x=0 THEN
			ATAN2=SGN(y)*pi/2
		ELSE
			ATAN2=ATAN(y/x) - (x<0)*pi
		END IF
	END FUNCTION
	.MaskChannelAdd "m1"
	Msg$ = "Enter the number of rotation steps desired: " & CHR(13) & \\
		"Even dividers of 360 work best for large numbers," & CHR(13) & \\
		"for example 90 plots fine, 50 does not."
	uix$ = INPUTBOX(Msg$)
	n = VAL(uix$)
	IF n = 0 THEN n = 12
	xstep& = 360/n

For I = 1 TO n-1 STEP 1
	xrot& = I*xstep&	' angle of rotation in degrees 
	rot = ANGLECONVERT(1,2,xrot&)	' angle of rotation in radians
	cx& = csw&/2			' default center of rotation 
	cy& = csh&/2
	.GetMaskRectangle l&, t&, r&, b&
	r&=r&+1			' mask size correction factor
	b&=b&+1			' mask size correction factor
	w# = r&-l&		' width of mask
	h# = b&-t&		' height of mask
	da# = ATAN2(h,w)	' diagonal angle of corner 2
	Ra# = SQR(w*w + h*h)/2	' radius size to corner positions of bounding box
	' find center of mask 
	ocx&= (l&+r&)/2
	ocy&= (t&+b&)/2
	' calculate rotation of offset (if any)
	ox# = ocx-cx		' x-offset	
	oy# = cy-ocy		' y-offset (with -y)
	oa# = ATAN2(oy,ox)	' angle of offset
	ro# = SQR(ox*ox+oy*oy)	' length of offset radius
	' calculate final rotated offset
	fox& = ro*cos(oa+rot)
	foy& = -ro*sin(oa+rot)	' (with -y)
		
	' new corner positions converted to -y space
	' new corner positions translated to screen center (200, 200)
	' new corner positions translated for rotated offset
	
	x1& = cx-Ra*cos(da-rot)+fox
	y1& = cy-Ra*sin(da-rot)+foy

	x2& = cx+Ra*cos(da+rot)+fox
	y2& = cy-Ra*sin(da+rot)+foy
	
	x3& = cx+Ra*cos(da-rot)+fox
	y3& = cy+Ra*sin(da-rot)+foy
	
	x4& = cx-Ra*cos(da+rot)+fox
	y4& = cy+Ra*sin(da+rot)+foy
	
	.MaskDistort x1&, y1&, x2&, y2&, x3&, y3&, x4&, y4&, TRUE	' plot it

	.MaskChannelAdd "m" & STR(I+1)
	.MaskChannelToMask 0, 0
Next I
' ............................................................
' Create transparent overlay view
FOR J = 0 TO n-1
	.MaskChannelToMask J, 0								' >>>>>>> edit here:
	.EditFill 4, 90, 100, 1, 0, 0, csh&-1, 0, csh&-1, 0, csh&-1 ' fill merge mode, transparency
		.FillSolid 5, 0, 0, 0, 0							'and here for color
		.EndEditFill
NEXT J
' Create a shape mask
FOR K = 0 TO n-1
	.MaskChannelToMask K, 1	
NEXT K
.MaskChannelAdd "shape"
END WITHOBJECT