grf { grfid : "ZUU0"; name : string(STR_GRF_NAME); desc : string(STR_GRF_DESCRIPTION); version: 1; min_compatible_version: 1; } switch (FEAT_INDUSTRIES, SELF, switch_prod_change, [ STORE_PERM(extra_callback_info1, 0), extra_callback_info1 ] { return 0; } item (FEAT_INDUSTRIES, item_industry_coal_mine) { property { substitute: 00; // coal mine override: 00; } graphics { random_prod_change: switch_prod_change; } }