# DECgraphics
DECgraphics is an option that displays walls as continuous lines rather than as broken dashes, which is the best that plain ASCII can do.  It also displays certain dungeon features with distinct symbols. DECgraphics is a smaller character set than IBMgraphics, so it is missing some symbols, particularly on the Rogue level.
DECgraphics requires a display device that displays DEC Special Graphics. DEC Special Graphics works by sending the terminal an escape code which tells it to toggle to an alternate character set with line drawing characters.  The curses SYMSET also uses DEC Special Graphics to approximate IBMgraphics.
To use DECgraphics, the option must be set to TRUE, either in-game or in the configuration file.

The complete symbol list
Because the DEC Special Graphics character set is limited and lacks the double line drawing characters, the Rogue level is rendered using only normal ASCII characters.
The symbols affected by DECgraphics in the normal dungeon are listed here.  DEC Special Graphics is a 7bit system. The code points listed here use the NetHack internal representation, which sets the 8th bit high.

Code point
Usage
Appearance
ASCII

0xf8
vertical wall
│
|

0xf1
horizontal wall
─
-

0xec
top left corner
┌
-

0xeb
top right corner
┐
-

0xed
bottom left corner
└
-

0xea
bottoom right corner
┘
-

0xee
cross wall
┼
-

0xf6
T up wall
┴
-

0xf7
T down wall
┬
-

0xf5
T left wall
┤
|

0xf4
T right wall
├
|

0xfe
normal door
·
.

0xe1
vertical open door
▒
-

0xe1
horizontal open door
▒
|

0xfc
bars
≠ or π
#

0xe7
tree
±
#

0xfe
room
·
.

0xf9
up ladder
≤
&lt;

0xfa
down ladder
≥
&gt;

0xfb
altar
π or _
_

0xe0
pool
◆
}

0xfe
ice
·
.

0xe0
lava
◆
}

0xfe
vertical open drawbridge
·
.

0xfe
horizontal open drawbridge
·
.

0xe0
under water
◆
}

0xf8
vertical beam
│
|

0xf1
horizontal beam
─
-

0xef
swallow top center
⎺
-

0xf8
swallow middle left
│
|

0xf8
swallow middle right
│
|

0xf3
swallow bottom center
⎽
-

0xef
explosion top center
⎺
-

0xf8
explosion middle left
│
|

0xf8
explosion middle right
│
|

0xf3
explosion bottom center
⎽
-

In the above table, "bars" and "altar" are listed with two appearances.  The first applies to 3.6.3 or newer.
The second applies to 3.6.2 and prior.
These symbols can be reinstated by putting the following line into the configuration file:

 SYMBOLS=S_altar:_,S_bars:\m{