code: public DepictionGenerator withMappedRxnAlign(boolean val) {
          DepictionGenerator copy = new DepictionGenerator(this);
          copy.alignMappedReactions = val;
          return copy;
      }
docs: Specifies that reactions with atom-atom mappings should have their reactants/product
  coordinates aligned. Default: true.
  
  @param val setting value
  @return new generator for method chaining