#version 410

uniform float eyePos;
uniform sampler2D texture1;
uniform bool doTexture;
in vec3 xyzV;

out vec4 fragColor;

vec3 mf(vec3 x)
{
    return x - floor(x);
}

float pi = 3.141592653589793238;

void main (void)
{
    vec3 xyz = xyzV;
    
    float lon = atan(xyz.y, xyz.x);
    float lat = atan(xyz.z, length(xyz.xy));
    
    vec2 b = vec2(lon,lat);
    vec2 c = b * 36.0 / 2.0 / pi; // marks ever 10 degrees
    
    ivec2 d = ivec2(c + vec2(10000,10000)); // for checkering, integer coords
    
    c -= floor(c);
    fragColor = vec4(c, 1.0, 1.0);
    
    float lineWidth = 0.032;
    float xThresh = lineWidth / cos(lat); // prevent narrowing of lines at the poles
    int oe = (d.x + d.y + 10000) % 2;
    fragColor = c.x < xThresh || c.y < lineWidth ? vec4(0.1, 0.9, 0.1, 1.0) : oe > 0 ? vec4(.3,.4,.2,1) : vec4(.6,.7,.8,2);
    
    fragColor *= vec4(.4,.4,.4,1);
    
    if(doTexture)
    {
        vec2 k = b / (2.0 * pi);
        k = b / vec2(2 * pi, pi);
        k = (k + vec2(1.0, 1.0) / 2.0);
        fragColor = (fragColor + texture(texture1, k)) / 2.0;
        
        fragColor = texture(texture1, k);
    }
    
}