1do_arc(3)                       Allegro manual                       do_arc(3)
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NAME

6       do_arc - Calculates all the points in a circular arc. Allegro game pro‐
7       gramming library.
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SYNOPSIS

10       #include <allegro.h>
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13       void do_arc(BITMAP *bmp, int x, int y, fixed a1, fixed a2, int  r,  int
14       d, void (*proc)(BITMAP *bmp, int x, int y, int d));
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DESCRIPTION

17       Calculates  all  the  points in a circular arc around point (x, y) with
18       radius r, calling the supplied function for  each  one.  This  will  be
19       passed a copy of the bmp parameter, the x and y position, and a copy of
20       the d parameter, so it is suitable for use  with  putpixel().  The  arc
21       will  be  plotted in an anticlockwise direction starting from the angle
22       a1 and ending when it reaches a2. These values are specified  in  16.16
23       fixed  point format, with 256 equal to a full circle, 64 a right angle,
24       etc.  Zero is to the right of  the  centre  point,  and  larger  values
25       rotate anticlockwise from there. Example:
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27          void draw_explosion_ring(BITMAP *bmp, int x, int y, int d)
28          {
29             ...
30          }
31             do_arc(screen, SCREEN_W/2, SCREEN_H/2,
32                 itofix(-21), itofix(43), 50, flame_color,
33                 draw_explosion_ring);
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SEE ALSO

37       do_circle(3), do_ellipse(3), do_line(3), arc(3)
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41Allegro                          version 4.2.2                       do_arc(3)
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