Texas Instruments TI-84 - Manual (Page 199)

Chapter 8: Draw Instructions 196
pattern specifies one of four shading patterns.
patres specifies one of eight shading resolutions.
Shade(lowerfunc,upperfunc[,Xleft,Xright,pattern,patres])
pattern=1
pattern=2
pattern=3
pattern=4 vertical (default)
horizontal
negative—slope 45
¡
positive—slope 45
¡
patres=1
patres=2
patres=3
patres=4
patres=5
patres=6
patres=7
patres=8 shades every pixel (default)
shades every second pixel
shades every third pixel
shades every fourth pixel
shades every fifth pixel
shades every sixth pixel
shades every seventh pixel
shades every eighth pixel