Q21947: CIRCLE Starting Angle of -0 Does Not Draw Line from Center

Article: Q21947
Product(s): See article
Version(s): 2.00 2.01 3.00 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | B_BasicCom | mspl13_basic
Last Modified: 29-DEC-1989

In SCREEN 1 or 2 (or a higher graphics mode such as SCREEN 8), a
CIRCLE statement with a start or end angle value of negative zero (-0)
does not generate a line from the circle edge to the center in
QuickBASIC Versions 2.00, 2.01, 3.00, 4.00, 4.00b, and 4.50, Microsoft
BASIC Compiler Versions 6.00 and 6.00b for MS-DOS, and Microsoft BASIC
PDS Version 7.00. It does generate the line in BASICA or GW-BASIC
Version 3.20.

The following is an example:

   10 SCREEN 1
   20 X=0
   25 REM  Radius=100, -x=start angle, 1=end angle:
   30 CIRCLE (160,100),100,,-X,1

A workaround is to use x=.00001 instead of x=0 in the above program,
as follows:

   10 SCREEN 1
   20 X=.00001
   30 CIRCLE (160,100),100,,-X,1

Microsoft considers this to be an acceptable difference between the
QuickBASIC Compiler and the BASIC interpreters.