I am reading the The OpenGLŪ Shading Language (Language Version: 1.2) http://www.opengl.org/registry/doc/G...ull.1.20.8.pdf mentions, "8.9 Noise Functions - Noise functions are available to both fragment and vertex shaders. ".

I have the following code snippet on my fragment shader:
Code :
			float x = 0.5;
			float noise = noise1(x);

It gives me the following error:

Code :
ERROR: 0:26: 'noise1' : no matching overloaded function found

What did I do wrong?

Thanks in advance for your help.