LinearGradientFilling

LinearGradientFilling[{col1,col2,…,coln}] is a two-dimensional graphics directive specifying that faces of polygons and other filled graphics objects are to be drawn using a progressive transition between colors coli along a straight horizontal line.

LinearGradientFilling[{pos1,pos2,…,posn}->{col1,col2,…,coln}] uses the colors coli at the scaled positions posi.

LinearGradientFilling[{pos1,pos2,…,posn}->{col1,col2,…,coln},dir] draws along the straight line with a direction dir.

LinearGradientFilling[{pos1,…,posn}->{col1,…,coln},dir,padding] uses the specified padding when drawing beyond the boundary positions pos1 and posn. 

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