1set_clip_rect(3)                Allegro manual                set_clip_rect(3)
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NAME

6       set_clip_rect  -  Sets the clipping rectangle of a bitmap. Allegro game
7       programming library.
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SYNOPSIS

10       #include <allegro.h>
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13       void set_clip_rect(BITMAP *bitmap, int x1, int y1, int x2, int y2);
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DESCRIPTION

16       Each bitmap has an associated clipping rectangle, which is the area  of
17       the  image  that  it is OK to draw onto. Nothing will be drawn to posi‐
18       tions outside this space. This function sets the clipping rectangle for
19       the  specified bitmap. Pass the coordinates of the top-left and bottom-
20       right corners of the clipping rectangle in this order; these  are  both
21       inclusive,  i.e. set_clip_rect(bitmap, 16, 16, 32, 32) will allow draw‐
22       ing to (16, 16) and (32, 32), but not to (15, 15) and (33, 33).
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24       Drawing operations will be performed (at least partially) on the bitmap
25       as  long  as  the  first  coordinates of its clipping rectangle are not
26       greater than the second  coordinates  and  its  intersection  with  the
27       actual  image is non-empty. If either condition is not fulfilled, draw‐
28       ing will be turned off for the bitmap, e.g.
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30          set_clip_rect(bmp, 0, 0, -1, -1); /* disable drawing on bmp */
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32       Note that passing "out-of-bitmap" coordinates is allowed, but they  are
33       likely   to   be   altered   (and   so   the  coordinates  returned  by
34       get_clip_rect() will be different).  However,  such  modifications  are
35       guaranteed  to  preserve the external effect of the clipping rectangle,
36       that is not to modify the actual area of the image that  it  is  OK  to
37       draw onto.
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SEE ALSO

41       get_clip_rect(3),          add_clip_rect(3),         set_clip_state(3),
42       get_clip_state(3), ex12bit(3), excamera(3)
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46Allegro                          version 4.4.3                set_clip_rect(3)
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