Draw Path Block

Code	Parameters	Meaning
0	-	End of path (when writing a path, a parameter is used to indicate the remaining length of the block, which is updated as data is written and the end of path marker is moved)
1	Pointer	Continuation of path at pointer
2	X, Y	Move to x,y starting a new sub-path
3	X, Y	Move to x,y without starting a new sub-path (internal use)
4	-	Close sub-path with move
5	-	Close sub-path with line
6	CX1, CY1, CX2, CY2, X, Y	Bezier curve to x,y using control points cx1, cy1 and cx2, cy2
7	X, Y	Move to x,y without starting a new sub-path (mostly used for internal use)
8	X, Y	Line to x,y

Draw path blocks consist of a block of words; code(element type) followed by any parameters. The block is terminated by an ‘End of Path’ element.

There are some order constraints on these codes (element types):

path elements 2 and 3 start new subpaths
path elements 6,7 and 8 may only appear while there is a current subpath
path elements 4 and 5 may only appear while there is a current subpath, and end it, leaving no current subpath
path elements 2 and 3 can also be used to close the current subpath (which is part of starting a new subpath)

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