| XEVI(3) | Library Functions Manual | XEVI(3) | 
Bool XeviQueryVersion (Display *dpy,
    int *major_version_return,
    int *minor_version_return);
int XeviGetVisualInfo (Display *dpy, VisualID *visual,
    int n_visual, ExtendedVisualInfo ** evi_return,
    int * n_info_return);
XeviQueryExtension returns True if the Extended Visual Information extension is available on the given display. A client must call XeviQueryExtension before calling any other EVI function in order to negotiate a compatible protocol version; otherwise the client will get undefined behavior (EVI may or may not work).
XeviQueryVersion returns True if the request succeeded; the values of the major and minor protocol version supported by the server are returned in major_version_return and minor_version_return.
XeviGetVisualInfo returns a list of ExtendedVisualInfo structures that describe visual information beyond that supported by the core protocol. This includes layer information relevant for systems supporting overlays and/or underlay planes, and information that allows applications better to determine the level of hardware support for multiple colormaps. XeviGetVisualInfo returns Success if successful, or an X error otherwise. If the argument visual is NULL, then information for all visuals of all screens is returned. Otherwise, it's a pointer to a list of visuals for which extended visual information is desired. n_visual is the number of elements in the array visual. evi_return returns a pointer to a list of ExtendedVisualInfo. When done, the client should free the list using XFree. n_info_return returns the number of elements in the array evi_return.
The ExtendedVisualInfo structure has the following fields:
VisualID	core_visual_id
int 	screen
int 	level
unsigned int	transparency_type
unsigned int	transparency_value
unsigned int	min_hw_colormaps
unsigned int	max_hw_colormaps
unsigned int	num_colormap_conflicts
VisualID *  	colormap_conflicts
The combination of core_visual_id and screen number uniquely specify the visual being described.
level returns the level number for the visual, 0 for normal planes, > 0 for overlays, < 0 for underlays.
transparency_type returns the type of transparency supported by the visual. XEVI_TRANSPARENCY_NONE if there are no transparent pixels, XEVI_TRANSPARENCY_PIXEL if the visual supports a transparent pixel, XEVI_TRANSPARENCY_MASK if the visual supports transparent plane(s).
transparency_value returns the pixel/plane value to set for transparency if transparency_type isn't XEVI_TRANSPARENCY_NONE.
min_hw_colormaps and max_hw_colormaps return the minimum and maximum number of hardware colormaps backing up the visual.
num_colormap_conflicts returns the number of elements in colormap_conflicts. This array returns a list of visuals that may cause conflicts in the use of the hardware colormap. For example, if a 12-bit hardware colormap is overloaded to support 8-bit colormaps, the corresponding 8-bit visuals would conflict with the 12-bit visuals.
| X Version 11 | X FUNCTIONS |