1al_set_new_display_option(3) al_set_new_display_option(3)
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6 al_set_new_display_option - Allegro 5 API
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9 #include <allegro5/allegro.h>
10 void al_set_new_display_option(int option, int value, int importance)
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14 Set an extra display option, to be used when creating new displays on
15 the calling thread. Display options differ from display flags, and
16 specify some details of the context to be created within the window
17 itself. These mainly have no effect on Allegro itself, but you may
18 want to specify them, for example if you want to use multisampling.
19 The 'importance' parameter can be either:
21 · ALLEGRO_REQUIRE - The display will not be created if the setting can
23 not be met.
24 · ALLEGRO_SUGGEST - If the setting is not available, the display will
26 be created anyway with a setting as close as possible to the
27 requested one. You can query the actual value used in that case by
28 calling al_get_display_option(3) after the display has been created.
29 · ALLEGRO_DONTCARE - If you added a display option with one of the
31 above two settings before, it will be removed again. Else this does
32 nothing.
33 The supported options are:
35 ALLEGRO_COLOR_SIZE
37 This can be used to ask for a specific bit depth. For example
38 to force a 16-bit framebuffer set this to 16.
39 ALLEGRO_RED_SIZE, ALLEGRO_GREEN_SIZE, ALLEGRO_BLUE_SIZE,
41 ALLEGRO_ALPHA_SIZE Individual color component size in bits.
42 ALLEGRO_RED_SHIFT, ALLEGRO_GREEN_SHIFT, ALLEGRO_BLUE_SHIFT,
44 ALLEGRO_ALPHA_SHIFT Together with the previous settings these
45 can be used to specify the exact pixel layout the display should
46 use. Normally there is no reason to use these.
47 ALLEGRO_ACC_RED_SIZE, ALLEGRO_ACC_GREEN_SIZE, ALLEGRO_ACC_BLUE_SIZE,
49 ALLEGRO_ACC_ALPHA_SIZE This can be used to define the required
50 accumulation buffer size.
51 ALLEGRO_STEREO
53 Whether the display is a stereo display.
54 ALLEGRO_AUX_BUFFERS
56 Number of auxiliary buffers the display should have.
57 ALLEGRO_DEPTH_SIZE
59 How many depth buffer (z-buffer) bits to use.
60 ALLEGRO_STENCIL_SIZE
62 How many bits to use for the stencil buffer.
63 ALLEGRO_SAMPLE_BUFFERS
65 Whether to use multisampling (1) or not (0).
66 ALLEGRO_SAMPLES
68 If the above is 1, the number of samples to use per pixel. Else
69 0.
70 ALLEGRO_RENDER_METHOD:
72 0 if hardware acceleration is not used with this display.
73 ALLEGRO_FLOAT_COLOR
75 Whether to use floating point color components.
76 ALLEGRO_FLOAT_DEPTH
78 Whether to use a floating point depth buffer.
79 ALLEGRO_SINGLE_BUFFER
81 Whether the display uses a single buffer (1) or another update
82 method (0).
83 ALLEGRO_SWAP_METHOD
85 If the above is 0, this is set to 1 to indicate the display is
86 using a copying method to make the next buffer in the flip chain
87 available, or to 2 to indicate a flipping or other method.
88 ALLEGRO_COMPATIBLE_DISPLAY
90 Indicates if Allegro's graphics functions can use this display.
91 If you request a display not useable by Allegro, you can still
92 use for example OpenGL to draw graphics.
93 ALLEGRO_UPDATE_DISPLAY_REGION
95 Set to 1 if the display is capable of updating just a region,
96 and 0 if calling al_update_display_region(3) is equivalent to
97 al_flip_display(3).
98 ALLEGRO_VSYNC
100 Set to 1 to tell the driver to wait for vsync in al_flip_dis‐
101 play(3), or to 2 to force vsync off. The default of 0 means
102 that Allegro does not try to modify the vsync behavior so it may
103 be on or off. Note that even in the case of 1 or 2 it is possi‐
104 ble to override the vsync behavior in the graphics driver so you
105 should not rely on it.
106 ALLEGRO_MAX_BITMAP_SIZE
108 When queried this returns the maximum size (width as well as
109 height) a bitmap can have for this display. Calls to al_cre‐
110 ate_bitmap(3) or al_load_bitmap(3) for bitmaps larger than this
111 size will fail. It does not apply to memory bitmaps which
112 always can have arbitrary size (but are slow for drawing).
113 ALLEGRO_SUPPORT_NPOT_BITMAP
115 Set to 1 if textures used for bitmaps on this display can have a
116 size which is not a power of two. This is mostly useful if you
117 use Allegro to load textures as otherwise only power-of-two tex‐
118 tures will be used internally as bitmap storage.
119 ALLEGRO_CAN_DRAW_INTO_BITMAP
121 Set to 1 if you can use al_set_target_bitmap(3) on bitmaps of
122 this display to draw into them. If this is not the case soft‐
123 ware emulation will be used when drawing into display bitmaps
124 (which can be very slow).
125 ALLEGRO_SUPPORT_SEPARATE_ALPHA
127 This is set to 1 if the al_set_separate_blender(3) function is
128 supported. Otherwise the alpha parameters will be ignored.
129 ALLEGRO_AUTO_CONVERT_BITMAPS
131 This is on by default. It causes any existing memory bitmaps
132 with the ALLEGRO_CONVERT_BITMAP flag to be converted to a dis‐
133 play bitmap of the newly created display with the option set.
134 Since: 5.1.0
136 ALLEGRO_SUPPORTED_ORIENTATIONS
138 This is a bit-combination of the orientations supported by the
139 application. The orientations are the same as for al_get_dis‐
140 play_orientation(3) with the additional possibilities:
141 · ALLEGRO_DISPLAY_ORIENTATION_PORTRAIT
143 · ALLEGRO_DISPLAY_ORIENTATION_LANDSCAPE
145 · ALLEGRO_DISPLAY_ORIENTATION_ALL
147 PORTRAIT means only the two portrait orientations are supported,
149 LANDSCAPE means only the two landscape orientations and ALL
150 allows all four orientations. When the orientation changes
151 between a portrait and a landscape orientation the display needs
152 to be resized. This is done by sending an ALLEGRO_EVENT_DIS‐
153 PLAY_RESIZE(3) message which should be handled by calling
154 al_acknowledge_resize(3).
155 Since: 5.1.0
157 ALLEGRO_OPENGL_MAJOR_VERSION
159 Request a specific OpenGL major version.
160 Since: 5.1.13
162 ALLEGRO_OPENGL_MINOR_VERSION
164 Request a specific OpenGL minor version.
165 Since: 5.1.13
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169 al_set_new_display_flags(3), al_get_display_option(3)
170Allegro reference manual al_set_new_display_option(3)