varying vec2 v_vTexcoord;
varying vec4 v_vColour;

uniform float f_alpha; 

void main()
{
    vec4 texColor = texture2D(gm_BaseTexture, v_vTexcoord);
    vec3 dkblue = vec3(0.0, 0.0, 0.5);
    
    gl_FragColor = vec4(mix(texColor.rgb, dkblue, f_alpha), texColor.a);
}