TPC stores the fill definitions in the TpcFills.dat file in the program folder. The file is self documented, explaining how to modify or add your own fill to TPC.
#TPC Fill Definition
# Syntax: Name, TPC ID, image pathname,AutoCAD Hatch,AutoCAD angle, AutoCAD space factor, AutoCAD linewidth factor
# Name - displayed in pull down list of fill types and placed in legend if fill is inserted as a legend item
# TPC ID - constant value stored with each filled object (do not modify this)
# image pathname - jpg, bmp, ico, etc
# AutoCAD hatch name - the AutoCAD hatch definitions are found in the TPC.PAT file in TPC's DXF folder
# AutoCAD hatch scale factor - multiplies the definition by this scale
None,0
Solid,1,,,SOLID
Horizontal,2,,,HORIZ
Vertical,3,,,VERT
Diagonal \,4,,,FDIAG
Diagonal /,5,,,BDIAG
Cross,6,,,GRID
Diagonal Cross,7,,,GRIDDIAG
Brick,8,,brick.bmp,BRICK,0.5
Brick Filled,9,,brick_fl.bmp
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