1al_set_new_bitmap_flags(3)                          al_set_new_bitmap_flags(3)
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NAME

6       al_set_new_bitmap_flags - Allegro 5 API
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SYNOPSIS

9              #include <allegro5/allegro.h>
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11              void al_set_new_bitmap_flags(int flags)
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DESCRIPTION

14       Sets the flags to use for newly created bitmaps.  Valid flags are:
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16       ALLEGRO_MEMORY_BITMAP
17              Create  a  bitmap residing in system memory.  Operations on, and
18              with, memory bitmaps will not be hardware accelerated.  However,
19              direct  pixel  access  can be relatively quick compared to video
20              bitmaps, which depend on the display driver in use.
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22              Note: Allegro's software rendering routines are currently  some‐
23              what unoptimised.
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25              Note:  Combining  ALLEGRO_VIDEO_BITMAP and ALLEGRO_MEMORY_BITMAP
26              flags is invalid.
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28       ALLEGRO_VIDEO_BITMAP
29              Creates a bitmap that resides in the video card  memory.   These
30              types  of bitmaps receive the greatest benefit from hardware ac‐
31              celeration.
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33              Note: Creating a video bitmap will fail if there is  no  current
34              display  or the current display driver cannot create the bitmap.
35              The latter will happen if for example the format  or  dimensions
36              are not supported.
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38              Note: Bitmaps created with this flag will be converted to memory
39              bitmaps when the last display is destroyed.  In most cases it is
40              therefore easier to use the ALLEGRO_CONVERT_BITMAP flag instead.
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42              Note:  Combining  ALLEGRO_VIDEO_BITMAP and ALLEGRO_MEMORY_BITMAP
43              flags is invalid.
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45       ALLEGRO_CONVERT_BITMAP
46              This is the default.  It will try to create a video  bitmap  and
47              if that fails create a memory bitmap.  Bitmaps created with this
48              flag when there is no active display will be converted to  video
49              bitmaps  next  time a display is created.  They also will remain
50              video bitmaps if the last display is destroyed and then  another
51              is created again.  Since 5.1.0.
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53              Note:  You  can  combine this flag with ALLEGRO_MEMORY_BITMAP or
54              ALLEGRO_VIDEO_BITMAP to force the initial type (and fail in  the
55              latter  case  if  no  video bitmap can be created) - but usually
56              neither of those combinations is very useful.
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58              You can use the display option  ALLEGRO_AUTO_CONVERT_BITMAPS  to
59              control which displays will try to auto-convert bitmaps.
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61       ALLEGRO_FORCE_LOCKING
62              Does  nothing since 5.1.8.  Kept for backwards compatibility on‐
63              ly.
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65       ALLEGRO_NO_PRESERVE_TEXTURE
66              Normally, every effort is taken to preserve the contents of bit‐
67              maps, since some platforms may forget them.  This can take extra
68              processing time.  If you know it  doesn't  matter  if  a  bitmap
69              keeps  its pixel data, for example when it's a temporary buffer,
70              use this flag to tell Allegro not to  attempt  to  preserve  its
71              contents.
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73       ALLEGRO_ALPHA_TEST
74              This  is a driver hint only.  It tells the graphics driver to do
75              alpha testing instead of alpha blending on bitmaps created  with
76              this  flag.   Alpha  testing  is usually faster and preferred if
77              your bitmaps have only one level of alpha  (0).   This  flag  is
78              currently  not  widely  implemented  (i.e., only for memory bit‐
79              maps).
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81       ALLEGRO_MIN_LINEAR
82              When drawing a scaled down version of  the  bitmap,  use  linear
83              filtering.   This usually looks better.  You can also combine it
84              with the MIPMAP flag for even better quality.
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86       ALLEGRO_MAG_LINEAR
87              When drawing a magnified version of a bitmap, use linear filter‐
88              ing.   This will cause the picture to get blurry instead of cre‐
89              ating a big rectangle for each pixel.  It  depends  on  how  you
90              want things to look like whether you want to use this or not.
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92       ALLEGRO_MIPMAP
93              This  can  only  be used for bitmaps whose width and height is a
94              power of two.  In that case, it will generate  mipmaps  and  use
95              them when drawing scaled down versions.  For example if the bit‐
96              map is 64x64, then extra bitmaps of  sizes  32x32,  16x16,  8x8,
97              4x4, 2x2 and 1x1 will be created always containing a scaled down
98              version of the original.
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SEE ALSO

101       al_get_new_bitmap_flags(3), al_get_bitmap_flags(3)
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104
105Allegro reference manual                            al_set_new_bitmap_flags(3)
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