hello
dear @minggangyin
like as you know: (No. grid * average grid size = area of shape)
but with respect to below picture:
No. grid=7379
average grid size = 0.06 m2
total area=7379*0.06=442.74 m2
but my total area is just 18.2 m2. (i calculated area by rhino and i created my shape in rhino too.)
best
AHAD