A problem about ccBlendFunc

Halo, new to openGLES and shader, so this question might be rookie, don’t make fun of me.XD

Currently I am trying to blend a gray texture to a single sprite, so that the sprite would look like darkened.
Everything looks fine but I find that the mask effects all the sprites in the scene.

For example,
I have “A” - the mask, “B” - the sprite, “C” - the background,
I want A to dark B, but has no effect to C.

I am grateful if there is a way to do this.
Thank you guys.~~

Like darkened?You just call the B-sprite’s setColor fun.

WenHai Lin wrote:

Like darkened?You just call the B-sprite’s setColor fun.

Thx for answering!
Besides Darkened,
there are some additional special effects I want to add like darken only a part of B, the rest stay normal, for example a HP gauge.
So I don’t want to effect the background C.