unit Functs;

interface

uses
  WinTypes, Classes, Graphics, SysUtils;

type
  TPoint2D = record
    X, Y: Real;
  end;
  TPoint3D = record
    X, Y, Z: Real;
  end;

function Point2D(X, Y: Real): TPoint2D;
function RoundPoint(P: TPoint2D): TPoint;
function FloatPoint(P: TPoint): TPoint2D;
function Point3D(X, Y, Z: Real): TPoint3D;
function Angle2D(P: TPoint2D): Real;
function Dist2D(P: TPoint2D): Real;
function Dist3D(P: TPoint3D): Real;
function RelAngle2D(PA, PB: TPoint2D): Real;
function RelDist2D(PA, PB: TPoint2D): Real;
function RelDist3D(PA, PB: TPoint3D): Real;
procedure Rotate2D(var P: TPoint2D; Angle2D: Real);
procedure RelRotate2D(var P: TPoint2D; PCentr: TPoint2D; Angle2D: Real);
procedure Move2D(var P: TPoint2D; Angle2D, Distance: Real);
function Between(PA, PB: TPoint2D; Preference: Real): TPoint2D;
function DistLine(A, B, C: Real; P: TPoint2D): Real;
function Dist2P(P, P1, P2: TPoint2D): Real;
function DistD1P(DX, DY: Real; P1, P: TPoint2D): Real;
function NearLine2P(P, P1, P2: TPoint2D; D: Real): Boolean;
function AddPoints(P1, P2: TPoint2D): TPoint2D;
function SubPoints(P1, P2: TPoint2D): TPoint2D;

function Invert(Col: TColor): TColor;
function Dark(Col: TColor; Percentage: Byte): TColor;
function Light(Col: TColor; Percentage: Byte): TColor;
function Mix(Col1, Col2: TColor; Percentage: Byte): TColor;
function MMix(Cols: array of TColor): TColor;
function Log(Base, Value: Real): Real;
function Modulator(Val, Max: Real): Real;
function M(I, J: Integer): Integer;
function Tan(Angle2D: Real): Real;
procedure Limit(var Value: Integer; Min, Max: Integer);
function Exp2(Exponent: Byte): Word;
function GetSysDir: String;
function GetWinDir: String;

implementation

function Point2D(X, Y: Real): TPoint2D;
begin
  Point2D.X := X;
  Point2D.Y := Y;
end;

function RoundPoint(P: TPoint2D): TPoint;
begin
  RoundPoint.X := Round(P.X);
  RoundPoint.Y := Round(P.Y);
end;

function FloatPoint(P: TPoint): TPoint2D;
begin
  FloatPoint.X := P.X;
  FloatPoint.Y := P.Y;
end;

function Point3D(X, Y, Z: Real): TPoint3D;
begin
  Point3D.X := X;
  Point3D.Y := Y;
  Point3D.Z := Z;
end;

function Angle2D(P: TPoint2D): Real;
begin
  if P.X = 0 then
  begin
    if P.Y > 0 then Result := Pi / 2;
    if P.Y = 0 then Result := 0;
    if P.Y < 0 then Result := Pi / -2;
end
else
Result := Arctan(P.Y / P.X);

if P.X < 0 then
begin
if P.Y < 0 then Result := Result + Pi;
if P.Y >= 0 then Result := Result - Pi;
  end;

  If Result < 0 then Result := Result + 2 * Pi;
end;

function Dist2D(P: TPoint2D): Real;
begin
Result := Sqrt(P.X * P.X + P.Y * P.Y);
end;

function Dist3D(P: TPoint3D): Real;
begin
Dist3d := Sqrt(P.X * P.X + P.Y * P.Y + P.Z * P.Z);
end;

function