How can I create a pat file (hatch) for this image?

[tsui224567]

I have try the the introduction from youtube, but the error messages are always 

existed. I don't know why. Does anyone can transform these pattern into code?

[hugha]

Try this:

;-------------------------------------------------------------------------------
; Written by HatchKit Professional
; HatchKit Professional (c)1990-2019 Cadro Pty Ltd
; www.hatchkit.com.au/
;-------------------------------------------------------------------------------
;-Date : 2020-03-15
;-Time : 17:02:31
;-HatchKit Version : 3.1.11.2740
;-HatchKit Output Filetype : AutoCAD format
;-------------------------------------------------------------------------------
*Entities,DXF Entity Section
-90,0,149.63,49.8753,35,99.751,-0.2486
-90,15,149.63,49.8753,35,99.751,-0.2486
-0.02806264,0,49.875,12285.0,-0.28328495,15,-12340.0
-0.02806264,0,149.63,12285.0,-0.28328495,15,-12340.0

hth,

Hugh Adamson

[hak_vz]

Here you have an excellent free code for generating hatch patterns (hatchmaker.lisp from Lanny Schiele).

You create your hatch element in real dimensions and cut it with a rectangle. After that scale it all to rectangle 1 × 1 unit. All lines should be on a grid 0.01 × 0.01 ( dimensions rounded to two decimals), and angles rounded to two decimals.

@hugha  has provided a pattern that probably solves your current task, but using hatchmaker (lisp code) can help you to generate patterns you need. I'm using this code for many years and it helped me a lot. You just have to play with it to figure out how it works and how to use patterns it generates (appropriate scaling).

[Sea-Haven]

Here is a pat for a floor tile closer to what you want if dwg in mm  then scale is 1. The numbers should make sense.

*HT600x3003ET,600x300mm 3mm Free patterns from www.AUTOCADhatch.com
0,3,0, 0,603, 300,-3.0
0,3,3, 0,603, 300,-3.0
90,3,3, 0,303, 600,-3.0
90,0,3, 0,303, 600,-3.0