man ggi_mode (Fonctions bibliothèques) - ggi_mode, ggi_coord, ggi_graphtype : LibGGI mode description
NAME
ggi_mode, ggi_coord, ggi_graphtype : LibGGI mode description
SYNOPSIS
#include <ggi/ggi.h>
typedef struct { sint16 x, y; } ggi_coord;
typedef uint32 ggi_graphtype;
typedef struct { sint32 frames; ggi_coord visible; ggi_coord virt; ggi_coord size; ggi_graphtype graphtype; ggi_coord dpp; } ggi_mode;
DESCRIPTION
The mode structure describes a visual configuration given by its size and other graphic properties.
STRUCTURE MEMBERS
- frames
 - The number of frames. Some displays have multi-buffer capabilites (double-buffering, triple-buffering...). See libggi frame-related functions for information on working with multiple frames.
 - visible
 - The size of the visible area. This is what the user will see.
 - virt
 - The virtual size of the visual. It can be larger (but not smaller) than the visible area, in which case only a part of it is displayed. It is useful for scrolling or backing up portions of screen efficiently. See ggi[Set|Get]Origin functions for more.
 - size
 - TODO : Write something here.
 - graphtype
 - It holds information on the type of display. libggi defines macros to construct graphtypes values or access individual field.
 - depth ( access via GT_DEPTH(gt), GT_SETDEPTH(gt,x) )
 - The number of significant bits holding color information.
 - size ( access via GT_SIZE(gt), GT_SETSIZE(gt,x) )
 - The actual size (in bits) of a pixel. For instance, on a 32 bits X server the pixel size is 32 but the depth is only 24 (8bits RGB channels, 8 unused).
 - scheme ( access via GT_SCHEME(gt), GT_SETSCHEME(gt,x) )
 - The following schemes are available :
 - •
 - GT_TEXT : text mode only
 - •
 - GT_TRUECOLOR : true color mode
 - •
 - GT_GREYSCALE : pixels represent level of gray
 - •
 - GT_PALETTE : pixels are entries in a CLUT (Color Look-Up Table)
 - •
 - GT_STATIC_PALETTE
 - •
 - GT_SUBSAMPLE_YUV
 - •
 - GT_SUBSAMPLE_U_YCRBR
 - •
 - GT_SUBSAMPLE_S_YCRBR
 - •
 - GT_NIL
 
- subscheme ( access via GT_SUBSCHEME(gt) , GT_SETSUBSCHEME(gt,x) )
 - One of:
 - •
 - GT_SUB_REVERSE_ENDIAN
 - •
 - GT_SUB_HIGHBIT_RIGHT
 - •
 - GT_SUB_PACKED_GETPUT
 
Graphtypes can be constructed directly or via the GT_CONSTRUCT(depth,scheme,size) macro. The following common graphtypes are defined :
- •
 - GT_TEXT16
 - •
 - GT_TEXT32
 - •
 - GT_1BIT
 - •
 - GT_2BIT
 - •
 - GT_4BIT
 - •
 - GT_8BIT
 - •
 - GT_15BIT
 - •
 - GT_16BIT
 - •
 - GT_24BIT
 - •
 - GT_32BIT
 - •
 - GT_AUTO
 - •
 - GT_INVALID
 
- dpp
 - It stands for dot-per-pixel.
 
When filling a mode structure for setting a visual, any field can be assigned GGI_AUTO (GT_AUTO for graphtype) if a specific value isn't required.
SEE ALSO
ggiCheckMode(3), ggiSetMode(3)