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#define INVERSE_2PI 0.1591549430918953358
uniform sampler2D gradTabTexture;
uniform lowp float opacity;
uniform highp float angle;
varying highp vec2 coord;
void main()
{
highp float t;
if (abs(coord.y) == abs(coord.x))
t = (atan(-coord.y + 0.002, coord.x) + angle) * INVERSE_2PI;
else
t = (atan(-coord.y, coord.x) + angle) * INVERSE_2PI;
gl_FragColor = texture2D(gradTabTexture, vec2(t - floor(t), 0.5)) * opacity;
}
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