When this option is enabled, the X server does the following:

•Specifies that the overlay visual has 256 entries.

•Creates the default colormap with entry 255 pre-allocated to Transparent. A client calling XAllocNamedColor for entry Transparent in the default colormap will be returned entry 255.

•For all other colormaps, returns all 256 entries as allocable, but issues a warning message:

Warning: XCreateColormap is creating 256 entry cmaps in overlay visual. Though allocable, entry 255 is hard-coded to transparency.

This warning is issued once per server execution.

CRX-48Z Device-Dependent Information

Supported Visuals

The following visuals are supported:

•Class PseudoColor Depth 8 Layer Image -

supports DBE and MBX hardware double-buffering

•Class PseudoColor Depth 8 Layer Overlay - supports DBE and MBX software double-buffering

•Class DirectColor Depth 24 Layer Image –

•supports DBE and MBX hardware double-buffering

•Class TrueColor Depth 24 Layer Image -

supports DBE and MBX hardware double-buffering

Supported Screen Options

The following Screen Options are supported:

•CountTransparentInOverlayVisual

•SwapBuffersOnVBlank

•ImageTextViaBitMap

•EnableIncludeInferiorsFix

CRX-48Z Transparent Overlay Visuals

The default number of colormap entries in the overlay visual for the CRX-48Z is 255. Entry 255 is excluded because its value is hard-coded to transparent (that is, show the image planes).

This may have the following two consequences for X11 applications running in the overlay planes (the default visual):

•Clients attempting to allocate 256 entries do not have their request granted.

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Graphics Administration Guide for HP-UX 10.20