src/main/java/org/gm4java/im4java/GMOperation.java
public GMOperation gravity(final Gravity value) {
        if (value == null) {
            throw new IllegalArgumentException("Gravity value must be defined");
        }
        gravity(value.toString());
        return this;
    }
public GMOperation gravity(final Gravity value) {
        if (value == null) {
            throw new IllegalArgumentException("Gravity value must be defined");
        }
        gravity(value.toString());
        return this;
    }
Defines the gravity for geometry-based operations. See documentation for more details, as this option works in
conjunction with various options in different ways.

@param value
Gravity value to use, defining the coordinate system to use.
@return Builder object for chained options setup.