Can I get sprite position on fragment shader (*.fp file)? (SOLVED)

Questions
1

I thought

varying mediump vec4 position;

would give me the position of the sprite, but apparently not.
It give me warning, error, and, stopped dmengine instead.

WARNING:GRAPHICS: The fragment shader uses varying position, but previous shader does not write to it.
Out of resource error.

ERROR:GRAPHICS: gl error 1281: invalid value

Assertion failed: 0, file ..\src\opengl\graphics_opengl.cpp, line 1091

Do I need to pass the position via constant?

2

Yeah, I think the only solution is to pass the sprite position via constant.