Question of ImageMaterialProperty.repeat,need help plz

Here’s my demo

I have used a canvas as an image in ImageMaterialProperty and setted it as a material for a 3 segmengts line.And let this image repeat 21times in my demo.I want to see the image repeats evenly.It means that the length of each image in polyline is the same.
Also i find that each segment repeats the image 7 times and if I change the repeat times into 30 times, each segment repeate the image 10 times.(Each line segmengt always repeats (total repeat time/line segments amount))

Q: So how can the polyline repeats the image evenly.

Can anybody helps me plz :sneezing_face: