Bridgetek FT800, Руководство по программированию

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FT800 Series Programmer Guide
Version 2.1
Document Reference No.: BRT_000030 Clearance No.: BRT#037
141
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4.42 TAG_MASK
Control the writing of the tag buffer
Encoding
31 24 23 1 0
0x14 Reserved
ma
sk
Parameters
mask
Allow updates to the tag buffer. The initial value is one and it means the tag
buffer of the FT800 is updated with the value given by the TAG command.
Therefore, the following graphics objects will be attached to the tag value
given by the TAG command.
The value zero means the tag buffer of the FT800 is set as the default value,
rather than the value given by TAG command in the display list.
Description
Every graphics object drawn on screen is attached with the tag value which is
defined in the FT800 tag buffer. The FT800 tag buffer can be updated by TAG
command.
The default value of the FT800 tag buffer is determined by CLEAR_TAG and
CLEAR commands. If there is no CLEAR_TAG command present in the display
list, the default value in tag buffer shall be 0.
TAG_MASK command decides whether the FT800 tag buffer takes the value
from the default value of the FT800 tag buffer or the TAG command of the
display list.
Graphics context
The value of mask is part of the graphics context, as described in section 4.1
See also
TAG, CLEAR_TAG, STENCIL_MASK, COLOR_MASK