Drawing rotated ellipses, Please help.

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Ryan Burnside

Thanks for all the help so far.

After a brief head explosion and some mopping of the floor I came up with this.

Function draw_oval(centerx#,centery#,width#,height#,rot#,n#)
	' draw the shape with a for loop
	
	
	Local angle#=360.0/n
	Local r1#=width/2.0
	Local r2#=height/2.0

	For Local i#=0 To n-1
	
		Local x1#=centerx+Cos(i*angle)*r1
		Local y1#=centery+Sin(i*angle)*r2
		Local x2#=centerx+Cos((i+1)*angle)*r1
		Local y2#=centery+Sin((i+1)*angle)*r2
		' get new data
		Local d1#=point_distance(centerx,centery,x1,y1)
		Local a1#=point_direction(centerx,centery,x1,y1)
		Local fx#=centerx+Cos(a1+rot)*d1
		Local fy#=centery+Sin(a1+rot)*d1
		
		Local d2#=point_distance(centerx,centery,x2,y2)
		Local a2#=point_direction(centerx,centery,x2,y2)
		Local fx2#=centerx+Cos(a2+rot)*d2
		Local fy2#=centery+Sin(a2+rot)*d2
	
		DrawLine(fx,fy,fx2,fy2)
		
	Next
End Function

The problem if drawing even width ovals remains. I don't know how to draw an oval with an even width. Using a central pixel always will make the width odd. If I tell it to draw a 32x32 oval I get a 31x31 oval.