ScanPulseEffectOverlay

vec3 ScanPulseEffectOverlay(
    float lfTime,
    vec2 lScreenSpaceUV,
    vec3 lInputColour,
    vec3 lWorldPosition,
    vec4 lScanConfigPos,
    vec4 lColour1AndBlend,
    vec4 lColour2AndTime,
    inout vec3 lSunColourVec3 )
{
    // MIXING COLOURS
    if (lColour1AndBlend.w <= 0.0)
        return lInputColour;

    // Make the scan effect slower at the beginning
    lColour2AndTime.w = pow(lColour2AndTime.w, 3.0);

    vec3  lWorldToScanPt = lWorldPosition - lScanConfigPos.xyz;
    float lfDistToScanPt = length(lWorldToScanPt);

    // adjust distance so that values inside the pulse radius fall 0..1
    float lfDistanceScale = 2.0 / lfDistToScanPt;
    float lfRadius = 1.0 / lScanConfigPos.w;
    float lfCurrent01 = lfDistToScanPt * lScanConfigPos.w * lfRadius * lfDistanceScale;
    float lfTarget = lColour2AndTime.w * lfRadius * lfDistanceScale;

    // calculate wave parameters
    float lfAbsTargetToCurrent = abs(lfTarget - lfCurrent01) * 3.0;
    float lfCurrentToTarget = (lfCurrent01 - lfTarget) * 2.9;
    float lfBaseWaveMask = 1.0 - (lfAbsTargetToCurrent * 2.0);
    float lfEdge = clamp(lfBaseWaveMask, -0.0, 1.0);
    lfBaseWaveMask -= lfCurrentToTarget * 2.0;
    lfBaseWaveMask = clamp(lfBaseWaveMask, 0.0, 1.0);
    lfBaseWaveMask = smoothstep(0.0, 1.1, pow(lfBaseWaveMask, 8.0));
    float lfFineEdgeMask = smoothstep(0.88, 0.98, lfEdge * lfEdge) * 5.0;

    // get scan colors
    vec3 scanCol = lColour1AndBlend.xyz;
    vec3 scanCol2 = lColour2AndTime.xyz;

    // save original colors
    vec3 origColour = lInputColour;
    vec3 origSun = lSunColourVec3;

    // apply wave effect
    vec3 waveCol = mix(scanCol2, scanCol, lfAbsTargetToCurrent);
    lInputColour = mix(lInputColour, waveCol, lfBaseWaveMask);
    lSunColourVec3 = mix(lSunColourVec3, vec3(0.0), lfBaseWaveMask);

    // apply detail scan lines
    float scanDetailLines = clamp(
        sin((lScreenSpaceUV.y) * 1500.0 + lfTime* 5.0) * 0.8,
        0.0, 1.0);
    lInputColour = mix(lInputColour, scanCol, scanDetailLines * lfBaseWaveMask);
    lSunColourVec3 = mix(lSunColourVec3, vec3(0.0), scanDetailLines * lfBaseWaveMask);

    // apply edge line
    vec3 lEdgeColour = mix(vec3(1.0), vec3(1.0, 0.0, 0.0), smoothstep(0.25, 1.0, 0.9));

// calculate scan luminance
float lfScanLuminance = (lInputColour.x * 0.3) + (lInputColour.y * 0.59) + (lInputColour.z * 0.11);

// blend original and modified colors based on luminance and other factors
float alpha = 0.9;
origColour = mix(origColour,
    origColour * 0.0,
    (1.0 - lfScanLuminance) * scanDetailLines * lfBaseWaveMask * lColour1AndBlend.w);
lInputColour = mix(origColour, lInputColour, alpha*lColour1AndBlend.w);
lSunColourVec3 = mix(origSun, lSunColourVec3, alpha*lColour1AndBlend.w);

// return modified color
return lInputColour;

}