IPPM_PerformDilation.m

function [IdealXYNew, Result_SL, ErrorChange] = IPPM_PerformDilation( RealXY, IdealXY, Result_SL )

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    % cf. IPPM

    %This function calculates an optimal dilation factor D with given
    %dilation center

    CenterX         = Result_SL.GridCenterX;
    CenterY         = Result_SL.GridCenterY;
    [NumOfPoints,~] = size(RealXY);
    
    %First, Remove "Offset"
    IdealXYRelative = IdealXY - ones(NumOfPoints,1) * [CenterX CenterY];    
    RealXYRelative  = RealXY  - ones(NumOfPoints,1) * [CenterX CenterY];
    
    IdealCenterDistance = sqrt(IdealXYRelative(1)^2 + IdealXYRelative(2)^2);    
    RealCenterDistance  = sqrt(RealXYRelative(1)^2  + RealXYRelative(2)^2);
    
    DilationFactor      = mean( RealCenterDistance / IdealCenterDistance );
    IdealXYRelativeNew  = [IdealXYRelative(:,1) * DilationFactor, IdealXYRelative(:,2) * DilationFactor];
    IdealXYNew          = IdealXYRelativeNew + ones(NumOfPoints,1) * [CenterX CenterY];
    
    Result_SL.GridSpace = Result_SL.GridSpace * DilationFactor;
    
    ErrorChange     = IPPM_GetError( RealXY, IdealXY ) - IPPM_GetError( RealXY, IdealXYNew );
    %disp([' >>> Dilation: Error decreased by ',num2str(ErrorChange)])

end