fix a bug in shift uniformly
fix a bug in shift uniformly

thewtex/tomviz,thewtex/tomviz,cryos/tomviz,mathturtle/tomviz,OpenChemistry/tomviz,mathturtle/tomviz,mathturtle/tomviz,cryos/tomviz,thewtex/tomviz,cjh1/tomviz,OpenChemistry/tomviz,cryos/tomviz,cjh1/tomviz,OpenChemistry/tomviz,cjh1/tomviz,OpenChemistry/tomviz