Quarter-Circle Gradient

Is there any way to quarter the radial gradient in texcoord so i get it from green-left to red-top? I managed to create a quarter-circle bar and now im trying to set the gradient to it.

Thats what i managed to achieve
image
Idea ies to add a gradient to that quartercircle

Hope this helps:
GradientMapped

Thats exactly what i imagined to achieve. Thank you very much, you are the best!!!