[Description] Specifies the x-radius of the gradient ellipse, in the brush's coordinate space. [Method] 
SetRadiusX
G e t C e n t e r
G e t G r a d i e n t O r i g i n O f f s e t
G e t G r a d i e n t S t o p C o l l e c t i o n
G e t R a d i u s X
G e t R a d i u s Y
S e t C e n t e r
S e t G r a d i e n t O r i g i n O f f s e t
S e t R a d i u s X
S e t R a d i u s Y