use simpler code for shift_stack_uniformly
use simpler code for shift_stack_uniformly

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