Hi, I am just learning OpenGLES 2.0, and I am trying to use an array of color values for my vertex colors. Rather than use floats I wanted to use unsigned chars for the RGB values, to save memory.
It seems to work but the shader compile is producing this warning:

WARNING: 0:25: Overflow in implicit constant conversion, minimum range for lowp float is (-2,2)
Here is the shader code I am using. I assume that the divide by 255 is producing the warning? What is the correct way to do this? Surely passing floats for colors is not a better option?

attribute vec4 position;

attribute vec3 normal;
attribute lowp vec4 color;

varying lowp vec4 colorVarying;

uniform mat4 modelViewProjectionMatrix;
uniform mat3 normalMatrix;

void main()
vec3 eyeNormal = normalize(normalMatrix * normal);
vec3 lightPosition = vec3(0.0, 0.0, 1.0);

float nDotVP = max(0.0, dot(eyeNormal, normalize(lightPosition)));

colorVarying = (color/255.0) * nDotVP;

gl_Position = modelViewProjectionMatrix * position;