可以在DRC rule file 里面添加
FLAG OFFGRID {NO | YES [MAXIMUM WARNINGS {number | ALL}]}
Parameters
• NO
Keyword that instructs the tool not to issue a warning when an off-grid vertex is found on an
original shape. This is the default behavior when you do not include this statement in the
rule file.
• YES
Keyword that instructs the tool to issue a warning when an off-grid vertex is found on an
original shape.
• MAXIMUM WARNINGS {number | ALL}
Optional keyword set specified with YES that indicates the number of warnings to report.
The default is 100 warnings.
number — a positive integer specifying the number of warnings to report.
ALL — specifies that all warnings are reported.

打开后，要使用OFFGRID函数

OFFGRID layer {resolution | x-resolution y-resolution}
[INSIDE OF LAYER layer2 [RELATIVE | ABSOLUTE]]
[CENTERS] [EDGE] [REGION [value]]
[[OFFSET [x_offset y_offset] [INSIDE BY value | OUTSIDE BY value]] …]
[HINT]


Example 1
The following rule check implements the specification “Diffusion must be on a 0.025 micron
grid (assuming 1000 database units per user-unit)”:
rule { OFFGRID diffusion 25 }
Example 2
This example shows a special case. The following rule check checks metal to a two-databaseunit
resolution grid because 3 -1 is evaluated as 2:
rule {
OFFGRID metal 3 -1}
whereas the following example results in a compilation error due to the negative y value for the
snap grid:
rule {
OFFGRID metal 3 (-1)}