unit ugluVectorExHelper;

{$mode objfpc}{$H+}
{$modeswitch typehelpers}

interface

uses
  Classes, SysUtils;

type
  generic TgluVectorHelper<T> = class
  public type
    TBaseType = T;
    PBaseType = ^TBaseType;

    TVector2 = array[0..1] of T;
    TVector3 = array[0..2] of T;
    TVector4 = array[0..3] of T;

    PVector2 = ^TVector2;
    PVector3 = ^TVector3;
    PVector4 = ^TVector4;

  public
    class function Vector2(const x, y: T): TVector2; overload; inline;
    class function Vector3(const x, y, z: T): TVector3; overload; inline;
    class function Vector4(const x, y, z, w: T): TVector4; overload; inline;

    class function Equals(const v1: TVector2; const v2: TVector2): Boolean; overload; inline;
    class function Equals(const v1: TVector3; const v2: TVector3): Boolean; overload; inline;
    class function Equals(const v1: TVector4; const v2: TVector4): Boolean; overload; inline;

    class function ToString(const v: TVector2; const aRound: Integer = -3): String; overload;
    class function ToString(const v: TVector3; const aRound: Integer = -3): String; overload;
    class function ToString(const v: TVector4; const aRound: Integer = -3): String; overload;

    class function TryFromString(const s: String; out v: TVector2): Boolean; overload; inline;
    class function TryFromString(const s: String; out v: TVector3): Boolean; overload; inline;
    class function TryFromString(const s: String; out v: TVector4): Boolean; overload; inline;
    class function TryFromString(const s: String; p: PBaseType; aCount: Integer): Boolean;
  end;

  generic TgluVectorHelperI<T> = class(specialize TgluVectorHelper<T>)
  public
    class function Length(const v: TVector2): Double; overload; inline;
    class function Length(const v: TVector3): Double; overload; inline;
    class function Length(const v: TVector4): Double; overload; inline;

    class function SqrLength(const v: TVector2): Double; overload; inline;
    class function SqrLength(const v: TVector3): Double; overload; inline;
    class function SqrLength(const v: TVector4): Double; overload; inline;

    class function Multiply(const v: TVector2; const a: T): TVector2; overload; inline;
    class function Multiply(const v: TVector3; const a: T): TVector3; overload; inline;
    class function Multiply(const v: TVector4; const a: T): TVector4; overload; inline;

    class function Multiply(const v1, v2: TVector2): TVector2; overload; inline;
    class function Multiply(const v1, v2: TVector3): TVector3; overload; inline;
    class function Multiply(const v1, v2: TVector4): TVector4; overload; inline;

    class function Add(const v1, v2: TVector2): TVector2; overload; inline;
    class function Add(const v1, v2: TVector3): TVector3; overload; inline;
    class function Add(const v1, v2: TVector4): TVector4; overload; inline;

    class function Sub(const v1, v2: TVector2): TVector2; overload; inline;
    class function Sub(const v1, v2: TVector3): TVector3; overload; inline;
    class function Sub(const v1, v2: TVector4): TVector4; overload; inline;

    class function ClampVal(const v, aMin, aMax: T): T; overload; inline;
    class function Clamp(const v, aMin, aMax: TVector2): TVector2; overload; inline;
    class function Clamp(const v, aMin, aMax: TVector3): TVector3; overload; inline;
    class function Clamp(const v, aMin, aMax: TVector4): TVector4; overload; inline;
    class function Clamp(const v: TVector2; const aMin, aMax: T): TVector2; overload; inline;
    class function Clamp(const v: TVector3; const aMin, aMax: T): TVector3; overload; inline;
    class function Clamp(const v: TVector4; const aMin, aMax: T): TVector4; overload; inline;
  end;

  generic TgluVectorHelperF<T> = class(specialize TgluVectorHelperI<T>)
  public
    class function Normalize(const v: TVector2): TVector2; overload; inline;
    class function Normalize(const v: TVector3): TVector3; overload; inline;
    class function Normalize(const v: TVector4): TVector4; overload; inline;

    class function Divide(const v: TVector2; const a: T): TVector2; overload; inline;
    class function Divide(const v: TVector3; const a: T): TVector3; overload; inline;
    class function Divide(const v: TVector4; const a: T): TVector4; overload; inline;

    class function Dot(const v1: TVector2; const v2: TVector2): T; overload; inline;
    class function Dot(const v1: TVector3; const v2: TVector3): T; overload; inline;
    class function Dot(const v1: TVector4; const v2: TVector4): T; overload; inline;

    class function Cross(const v1: TVector3; const v2: TVector3): TVector3; overload; inline;

    class function Angle(const v1: TVector2; const v2: TVector2): Double; overload; inline;
    class function Angle(const v1: TVector3; const v2: TVector3): Double; overload; inline;
    class function Angle2(const v1: TVector2; const v2: TVector2): Double; overload; inline;
  end;

  TgluVectorP  = specialize TgluVectorHelper<Pointer>;
  TgluVectorE  = specialize TgluVectorHelper<Cardinal>;

  TgluVectorI  = specialize TgluVectorHelperI<Integer>;
  TgluVectorUS = specialize TgluVectorHelperI<Word>;
  TgluVectorUB = specialize TgluVectorHelperI<Byte>;

  TgluVectorF  = specialize TgluVectorHelperF<Single>;
  TgluVectorD  = specialize TgluVectorHelperF<Double>;

  TPointerTypeHelper = type helper for Pointer
    function ToString(const aRound: Integer = -3): String;
    class function TryFromString(s: String; out v: Pointer): Boolean; static;
  end;

  TCardinalTypeHelper = type helper for Cardinal
    function ToString(const aRound: Integer = -3): String;
    class function TryFromString(s: String; out v: Cardinal): Boolean; static;
  end;

  TIntegerTypeHelper = type helper for Integer
    function ToString(const aRound: Integer = -3): String;
    class function TryFromString(s: String; out v: Integer): Boolean; static;
  end;

  TWordTypeHelper = type helper for Word
    function ToString(const aRound: Integer = -3): String;
    class function TryFromString(s: String; out v: Word): Boolean; static;
  end;

  TByteTypeHelper = type helper for Byte
    function ToString(const aRound: Integer = -3): String;
    class function TryFromString(s: String; out v: Byte): Boolean; static;
  end;

  TSingleTypeHelper = type helper for Single
    function ToString(const aRound: Integer = -3): String;
    class function TryFromString(s: String; out v: Single): Boolean; static;
  end;

  TDoubleTypeHelper = type helper for Double
    function ToString(const aRound: Integer = -3): String;
    class function TryFromString(s: String; out v: Double): Boolean; static;
  end;

implementation

uses
  Math;

function IntToStrRounded(i: Int64; const aRound: Integer): String;
var p: Cardinal;
begin
  if (aRound > 0) then begin
    p := Round(power(10, aRound));
    i := i div p;
    i := i * p;
  end;
  result := IntToStr(i);
end;

function FloatToStrRounded(f: Extended; const aRound: Integer): String;
var p: Cardinal; fmt: TFormatSettings;
begin
  if (aRound > 0) then begin
    p := Round(power(10, aRound));
    f := Round(f / p) * p;
  end;
  fmt.DecimalSeparator := '.';
  result := Format('%.*f', [Max(0, -aRound), f], fmt);
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TPointerTypeHelper////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TPointerTypeHelper.ToString(const aRound: Integer): String;
begin
  result := '0x' + IntToHex({%H-}PtrUInt(self), 2 * SizeOf(Pointer));
end;

class function TPointerTypeHelper.TryFromString(s: String; out v: Pointer): Boolean;
var
 i: Int64;
begin
  s := StringReplace(s, '0x', '$', [rfReplaceAll, rfIgnoreCase]);
  result := TryStrToInt64(s, i);
  if result
    then v := {%H-}Pointer(PtrUInt(i))
    else v := nil;
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TCardinalTypeHelper///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TCardinalTypeHelper.ToString(const aRound: Integer): String;
begin
  result := IntToStrRounded(self, aRound);
end;

class function TCardinalTypeHelper.TryFromString(s: String; out v: Cardinal): Boolean;
var i: LongInt;
begin
  result := TryStrToInt(s, i);
  if result
    then v := i
    else v := 0;
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TIntegerTypeHelper////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TIntegerTypeHelper.ToString(const aRound: Integer): String;
begin
  result := IntToStrRounded(self, aRound);
end;

class function TIntegerTypeHelper.TryFromString(s: String; out v: Integer): Boolean;
begin
  result := TryStrToInt(s, v);
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TWordTypeHelper///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TWordTypeHelper.ToString(const aRound: Integer): String;
begin
  result := IntToStrRounded(self, aRound);
end;

class function TWordTypeHelper.TryFromString(s: String; out v: Word): Boolean;
var i: LongInt;
begin
  result := TryStrToInt(s, i);
  if result
    then v := i
    else v := 0;
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TByteTypeHelper///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TByteTypeHelper.ToString(const aRound: Integer): String;
begin
  result := IntToStrRounded(self, aRound);
end;

class function TByteTypeHelper.TryFromString(s: String; out v: Byte): Boolean;
var i: LongInt;
begin
  result := TryStrToInt(s, i);
  if result
    then v := i
    else v := 0;
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TSingleTypeHelper/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TSingleTypeHelper.ToString(const aRound: Integer): String;
begin
  result := FloatToStrRounded(self, aRound);
end;

class function TSingleTypeHelper.TryFromString(s: String; out v: Single): Boolean;
var f: TFormatSettings;
begin
  f.DecimalSeparator := '.';
  result := TryStrToFloat(s, v, f);
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TDoubleTypeHelper/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TDoubleTypeHelper.ToString(const aRound: Integer): String;
begin
  result := FloatToStrRounded(self, aRound);
end;

class function TDoubleTypeHelper.TryFromString(s: String; out v: Double): Boolean;
var f: TFormatSettings;
begin
  f.DecimalSeparator := '.';
  result := TryStrToFloat(s, v, f);
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TgluVectorHelper//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class function TgluVectorHelper.Vector2(const x, y: T): TVector2;
begin
  result[0] := x;
  result[1] := y;
end;

class function TgluVectorHelper.Vector3(const x, y, z: T): TVector3;
begin
  result[0] := x;
  result[1] := y;
  result[2] := z;
end;

class function TgluVectorHelper.Vector4(const x, y, z, w: T): TVector4;
begin
  result[0] := x;
  result[1] := y;
  result[2] := z;
  result[3] := w;
end;

class function TgluVectorHelper.Equals(const v1: TVector2; const v2: TVector2): Boolean;
begin
  result := (v1[0] = v2[0]) and (v1[1] = v2[1]);
end;

class function TgluVectorHelper.Equals(const v1: TVector3; const v2: TVector3): Boolean;
begin
  result := Equals(PVector2(@v1[0])^, PVector2(@v2[0])^) and (v1[2] = v2[2]);
end;

class function TgluVectorHelper.Equals(const v1: TVector4; const v2: TVector4): Boolean;
begin
  result := Equals(PVector3(@v1[0])^, PVector3(@v2[0])^) and (v1[3] = v2[3]);
end;

class function TgluVectorHelper.ToString(const v: TVector2; const aRound: Integer): String;
begin
  result := v[0].ToString(aRound) + '; ' + v[1].ToString(aRound);
end;

class function TgluVectorHelper.ToString(const v: TVector3; const aRound: Integer): String;
begin
  result := v[0].ToString(aRound) + '; ' + v[1].ToString(aRound) + '; ' + v[2].ToString(aRound);
end;

class function TgluVectorHelper.ToString(const v: TVector4; const aRound: Integer): String;
begin
  result := v[0].ToString(aRound) + '; ' + v[1].ToString(aRound) + '; ' + v[2].ToString(aRound) + '; ' + v[3].ToString(aRound);
end;

class function TgluVectorHelper.TryFromString(const s: String; out v: TVector2): Boolean;
begin
  result := TryFromString(s, @v[0], 2);
end;

class function TgluVectorHelper.TryFromString(const s: String; out v: TVector3): Boolean;
begin
  result := TryFromString(s, @v[0], 3);
end;

class function TgluVectorHelper.TryFromString(const s: String; out v: TVector4): Boolean;
begin
  result := TryFromString(s, @v[0], 4);
end;

class function TgluVectorHelper.TryFromString(const s: String; p: PBaseType; aCount: Integer): Boolean;
var
  i, j, l: Integer;
begin
  result := true;
  i := 1;
  j := 1;
  l := Length(s);
  while ({%H-}i <= {%H-}l) and (aCount > 0) and result {%H-}do begin
    if (s[i] = ';') or (i = l) then begin
      if (i = l) then inc(i);
      result := TBaseType.TryFromString(Trim(copy(s, j, i-{%H-}j)), p^);
      j      := i+1;
      inc(p);
      dec(aCount);
    end;
    inc(i);
  end;

  result := (aCount = 0);
  while (aCount > 0) do begin
    p^ := TBaseType(0);
    inc(p);
    dec(aCount);
  end;
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TgluVectorHelperI/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class function TgluVectorHelperI.Length(const v: TVector2): Double;
begin
  result := SQRT(v[0]*v[0] + v[1]*v[1]);
end;

class function TgluVectorHelperI.Length(const v: TVector3): Double;
begin
  result := SQRT(v[0]*v[0] + v[1]*v[1] + v[2]*v[2]);
end;

class function TgluVectorHelperI.Length(const v: TVector4): Double;
begin
  result := SQRT(v[0]*v[0] + v[1]*v[1] + v[2]*v[2]) * v[3];
end;

class function TgluVectorHelperI.SqrLength(const v: TVector2): Double;
begin
  result := v[0]*v[0] + v[1]*v[1];
end;

class function TgluVectorHelperI.SqrLength(const v: TVector3): Double;
begin
  result := v[0]*v[0] + v[1]*v[1] + v[2]*v[2];
end;

class function TgluVectorHelperI.SqrLength(const v: TVector4): Double;
begin
  result := (v[0]*v[0] + v[1]*v[1] + v[2]*v[2]) * v[3];
end;

class function TgluVectorHelperI.Multiply(const v: TVector2; const a: T): TVector2;
begin
  result[0] := v[0] * a;
  result[1] := v[1] * a;
end;

class function TgluVectorHelperI.Multiply(const v: TVector3; const a: T): TVector3;
begin
  result[0] := v[0] * a;
  result[1] := v[1] * a;
  result[2] := v[2] * a;
end;

class function TgluVectorHelperI.Multiply(const v: TVector4; const a: T): TVector4;
begin
  result[0] := v[0] * a;
  result[1] := v[1] * a;
  result[2] := v[2] * a;
  result[3] := v[3] * a;
end;

class function TgluVectorHelperI.Multiply(const v1, v2: TVector2): TVector2;
begin
  result[0] := v1[0] * v2[0];
  result[1] := v1[1] * v2[1];
end;

class function TgluVectorHelperI.Multiply(const v1, v2: TVector3): TVector3;
begin
  result[0] := v1[0] * v2[0];
  result[1] := v1[1] * v2[1];
  result[2] := v1[2] * v2[2];
end;

class function TgluVectorHelperI.Multiply(const v1, v2: TVector4): TVector4;
begin
  result[0] := v1[0] * v2[0];
  result[1] := v1[1] * v2[1];
  result[2] := v1[2] * v2[2];
  result[3] := v1[3] * v2[3];
end;

class function TgluVectorHelperI.Add(const v1, v2: TVector2): TVector2;
begin
  result[0] := v1[0] + v2[0];
  result[1] := v1[1] + v2[1];
end;

class function TgluVectorHelperI.Add(const v1, v2: TVector3): TVector3;
begin
  result[0] := v1[0] + v2[0];
  result[1] := v1[1] + v2[1];
  result[2] := v1[2] + v2[2];
end;

class function TgluVectorHelperI.Add(const v1, v2: TVector4): TVector4;
begin
  result[0] := v1[0] + v2[0];
  result[1] := v1[1] + v2[1];
  result[2] := v1[2] + v2[2];
  result[3] := v1[3] + v2[3];
end;


class function TgluVectorHelperI.Sub(const v1, v2: TVector2): TVector2;
begin
  result[0] := v1[0] - v2[0];
  result[1] := v1[1] - v2[1];
end;

class function TgluVectorHelperI.Sub(const v1, v2: TVector3): TVector3;
begin
  result[0] := v1[0] - v2[0];
  result[1] := v1[1] - v2[1];
  result[2] := v1[2] - v2[2];
end;

class function TgluVectorHelperI.Sub(const v1, v2: TVector4): TVector4;
begin
  result[0] := v1[0] - v2[0];
  result[1] := v1[1] - v2[1];
  result[2] := v1[2] - v2[2];
  result[3] := v1[3] - v2[3];
end;

class function TgluVectorHelperI.ClampVal(const v, aMin, aMax: T): T;
begin
  if (v < aMin) then
    result := aMin
  else if (v > aMax) then
    result := aMax
  else
    result := v;
end;

class function TgluVectorHelperI.Clamp(const v, aMin, aMax: TVector2): TVector2;
begin
  result[0] := ClampVal(v[0], aMin[0], aMax[0]);
  result[1] := ClampVal(v[1], aMin[1], aMax[1]);
end;

class function TgluVectorHelperI.Clamp(const v, aMin, aMax: TVector3): TVector3;
begin
  result[0] := ClampVal(v[0], aMin[0], aMax[0]);
  result[1] := ClampVal(v[1], aMin[1], aMax[1]);
  result[2] := ClampVal(v[2], aMin[2], aMax[2]);
end;

class function TgluVectorHelperI.Clamp(const v, aMin, aMax: TVector4): TVector4;
begin
  result[0] := ClampVal(v[0], aMin[0], aMax[0]);
  result[1] := ClampVal(v[1], aMin[1], aMax[1]);
  result[2] := ClampVal(v[2], aMin[2], aMax[2]);
  result[3] := ClampVal(v[3], aMin[3], aMax[3]);
end;

class function TgluVectorHelperI.Clamp(const v: TVector2; const aMin, aMax: T): TVector2;
begin
  result[0] := ClampVal(v[0], aMin, aMax);
  result[1] := ClampVal(v[1], aMin, aMax);
end;

class function TgluVectorHelperI.Clamp(const v: TVector3; const aMin, aMax: T): TVector3;
begin
  result[0] := ClampVal(v[0], aMin, aMax);
  result[1] := ClampVal(v[1], aMin, aMax);
  result[2] := ClampVal(v[2], aMin, aMax);
end;

class function TgluVectorHelperI.Clamp(const v: TVector4; const aMin, aMax: T): TVector4;
begin
  result[0] := ClampVal(v[0], aMin, aMax);
  result[1] := ClampVal(v[1], aMin, aMax);
  result[2] := ClampVal(v[2], aMin, aMax);
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TgluVectorHelperF/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class function TgluVectorHelperF.Normalize(const v: TVector2): TVector2;
var l: Double;
begin
  l := Length(v);
  result[0] := v[0] / l;
  result[1] := v[1] / l;
end;

class function TgluVectorHelperF.Normalize(const v: TVector3): TVector3;
var l: Double;
begin
  l := Length(v);
  result[0] := v[0] / l;
  result[1] := v[1] / l;
  result[2] := v[2] / l;
end;

class function TgluVectorHelperF.Normalize(const v: TVector4): TVector4;
begin
  result := v;
  if (result[3] <> 0) then
    result := Divide(v, v[3]);
  PVector3(@result[0])^ := Normalize(PVector3(@result[0])^);
end;

class function TgluVectorHelperF.Divide(const v: TVector2; const a: T): TVector2;
begin
  result[0] := v[0] / a;
  result[1] := v[1] / a;
end;

class function TgluVectorHelperF.Divide(const v: TVector3; const a: T): TVector3;
begin
  result[0] := v[0] / a;
  result[1] := v[1] / a;
  result[2] := v[2] / a;
end;

class function TgluVectorHelperF.Divide(const v: TVector4; const a: T): TVector4;
begin
  result[0] := v[0] / a;
  result[1] := v[1] / a;
  result[2] := v[2] / a;
  result[3] := v[3] / a;
end;

class function TgluVectorHelperF.Dot(const v1: TVector2; const v2: TVector2): T;
begin
  result := v1[0] * v2[0] + v1[1] * v2[1];
end;

class function TgluVectorHelperF.Dot(const v1: TVector3; const v2: TVector3): T;
begin
  result := v1[0] * v2[0] + v1[1] * v2[1] + v1[2] * v2[2];
end;

class function TgluVectorHelperF.Dot(const v1: TVector4; const v2: TVector4): T;
begin
  result := v1[0] * v2[0] + v1[1] * v2[1] + v1[2] * v2[2] + v1[3] * v2[3];
end;

class function TgluVectorHelperF.Cross(const v1: TVector3; const v2: TVector3): TVector3;
begin
  result[0] := v1[1] * v2[2] - v1[2] * v2[1];
  result[1] := v1[2] * v2[0] - v1[0] * v2[2];
  result[2] := v1[0] * v2[1] - v1[1] * v2[0];
end;

class function TgluVectorHelperF.Angle(const v1: TVector2; const v2: TVector2): Double;
begin
  result := ArcCos(Dot(v1, v2) / (Length(v1) * Length(v2)));
end;

class function TgluVectorHelperF.Angle(const v1: TVector3; const v2: TVector3): Double;
begin
  result := ArcCos(Dot(v1, v2) / (Length(v1) * Length(v2)));
end;

class function TgluVectorHelperF.Angle2(const v1: TVector2; const v2: TVector2): Double;
begin
  result := arctan2(
    v2[0] * v1[1] - v2[1] * v1[0],
    v2[0] * v1[0] + v2[1] * v1[1]);
end;

end.