2012

start_offset = 56 because ((55 - 45) * 256 / 45) = 56
end_offset = 28 because ((95 - 90) * 256 / 45) = 28
high_radius = 0 because (radius < 255)
radius = 3
starting octant = 1 because arc starts in the 45 degree
octant
ending octant = 2 because arc ends in the 90 degree octant
Codes 00C and 00D: Bulge-Specified Arcs
Special codes 00C and 00D (12 and 13) provide another mechanism for
including arc segments in shape descriptions.
They are similar to codes 8 and 9 in that you can use them to specify X-Y
displacements. However, codes 00C and 00D draw arcs by applying a bulge
factor to the displacement vector. Code 00C draws one arc segment, while
code 00D draws multiple arc segments (polyarcs) until it is terminated by a
(0,0) displacement.
Code 00C must be followed by three bytes describing the arc:
0C,X-displacement,Y-displacement,Bulge
Both the X and Y displacement and the bulge, which specifies the curvature
of the arc, can range from -127 to +127. If the line segment specified by the
displacement has length D, and the perpendicular distance from the midpoint
of that segment has height H, the magnitude of the bulge is ((2* H / D) * 127).
The sign is negative if the arc from the current location to the new location
is clockwise.
A semicircle has bulge 127 (or -127) and is the greatest arc that can be
represented as a single-arc segment using these codes (use two consecutive
arc segments for larger arcs). A bulge specification of 0 is valid and represents
a straight-line segment. Note, however, that using code 8 for a straight-line
segment saves a byte in the shape description.
Create Shape Definition Files | 115