BUG: CIRCLE(x,y),rad,,-0.1,0 Draws Only the Radius in Basic (67374)


The information in this article applies to:

  • Microsoft QuickBASIC Compiler for the Apple Macintosh 1.0
  • Microsoft QuickBASIC Compiler for the Apple Macintosh 1.0a
  • Microsoft QuickBASIC Compiler for the Apple Macintosh 1.0b
  • Microsoft QuickBASIC Compiler for the Apple Macintosh 1.0e
  • Microsoft QuickBASIC 4.0
  • Microsoft QuickBASIC 4.0b
  • Microsoft QuickBASIC 4.5
  • Microsoft BASIC Compiler for MS-DOS and OS/2 6.0
  • Microsoft BASIC Compiler for MS-DOS and OS/2 6.0b
  • Microsoft Basic Professional Development System (PDS) for MS-DOS and MS OS/2 7.0
  • Microsoft Basic Professional Development System (PDS) for MS-DOS and MS OS/2 7.1
This article was previously published under Q67374

SYMPTOMS

The CIRCLE command takes the following parameters: 
   CIRCLE[STEP](x,y),radius!,,start!,stop!
If you specify a start! value that is slightly larger than stop!, the CIRCLE command should draw an almost complete circle. However, if the difference between start! and stop! is very small, CIRCLE may draw only a point or radius. This problem happens in the interpreter environment and in compiled programs.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Changing the size of radius changes the requirement for the distance between start! and stop! necessary to reproduce the problem. When start! is near zero, leaving off the stop! produces different results from those obtained when stop! is specified. Use the following code examples to reproduce the problems described above.

Code Examples

' When start! or stop! is negative, CIRCLE draws a radius and
' treats the angle as positive. Without the negative sign, no
' radius is drawn.
'
SCREEN 12  'Problem occurs in any graphics screen mode.
10 CIRCLE (50, 50), 50, , -.01         'Works correctly.
20 CIRCLE (50, 150), 50, , -.01, 0     'Should be same as line
                                       '10 but draws only the radius.
30 CIRCLE (50, 250), 50, , -.011, 0    'Slightly larger difference
                                       'from start & stop works.
40 CIRCLE (420, 240), 200, , -.01, 0   'This works with same end/start
                                       'as line 20 but has larger
                                       'radius
On the Apple Macintosh, use the following code: 
CIRCLE (50, 50) 10, ,-0.001, 0
Modification Type:MinorLast Reviewed:8/16/2005
Keywords:kbbug KB67374
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