ugBASIC User Manual

   CIRCLE [x], [y], r[, c]
   CIRCLE x, y, rx, ry[, c]

The CIRCLE command in BASIC draws a circle on the screen. In other words, it defines a complete circle based on the coordinates and radius that you specify.

This command allows you to draw a circle with starting coordinates in (x,y) and radius r. The color is indicated by the parameter c. If the abscissa and/or ordinate is omitted, the last graphic position drawn will be used. In addition, the color can also be omitted and, if necessary, the last color set with the PEN or INK command will be used.

There is also another additional syntax, that can be used to draw ellipses: you can give both the radii rx and ry in the color determined by fq (see HIRES).

The accuracy of the circle depends on the resolution of your screen. Lower-resolution screens may display less sharp circles.

  ' Draw a circle
  CIRCLE 100,100,42
  ' Draw an ellipse
  CIRCLE 100,100,21,42
  CIRCLE ,,21,RED

See also the following example files:

• graphics_position_01.bas
• graphics_position_02.bas
• graphics_shapes_02.bas

 Ci

• Atari (400/800)
• Atari XL/XE
• Commodore 128 (MOS 8502)
• Commodore 128 (Zilog Z80)
• Commodore 64
• Commodore 64+REU
• TRS-80 Color Computer
• TRS-80 Color Computer 3
• ColecoVision
• Amstrad CPC 664
• Dragon 32
• Dragon 64
• Thomson MO5
• Thomson MO5
• Olivetti Prodest PC128
• Commodore PLUS/4
• SEGA SC-3000
• SEGA SG-1000
• VG-5000
• Commodore VIC-20
• ZX Spectrum 48

ELLIPSE

If you have encountered a problem using this command, if you think there is a bug or the explanation is unclear, please open an issue for this keyword on GitHub. Thank you!