Parameterized variations

2.10/Source/varpdj.pas

@@ -0,0 +1,123 @@
+unit varpdj;
+
+interface
+
+uses
+  BaseVariation, XFormMan;
+
+type
+  TVariationPDJ = class(TBaseVariation)
+  private
+    FA,FB,FC,FD: double;
+  public
+    constructor Create;
+
+    class function GetName: string; override;
+    class function GetInstance: TBaseVariation; override;
+
+    class function GetNrVariables: integer; override;
+    class function GetVariableNameAt(const Index: integer): string; override;
+
+    function SetVariable(const Name: string; var value: double): boolean; override;
+    function GetVariable(const Name: string; var value: double): boolean; override;
+
+
+    procedure CalcFunction; override;
+  end;
+
+implementation
+
+uses
+  Math;
+
+{ TVariationTest }
+
+///////////////////////////////////////////////////////////////////////////////
+procedure TVariationPDJ.CalcFunction;
+begin
+  FPx^ := FPx^ + vvar * (sin(FA * FTy^) - cos(FB * FTx^));
+  FPy^ := FPy^ + vvar * (sin(FC * FTx^) - cos(FD * FTy^));
+end;
+
+///////////////////////////////////////////////////////////////////////////////
+constructor TVariationPDJ.Create;
+begin
+  FA := 6 * Random - 3;
+  FB := 6 * Random - 3;
+  FC := 6 * Random - 3;
+  FD := 6 * Random - 3;
+end;
+
+///////////////////////////////////////////////////////////////////////////////
+class function TVariationPDJ.GetInstance: TBaseVariation;
+begin
+  Result := TVariationPDJ.Create;
+end;
+
+///////////////////////////////////////////////////////////////////////////////
+class function TVariationPDJ.GetName: string;
+begin
+  Result := 'pdj';
+end;
+
+///////////////////////////////////////////////////////////////////////////////
+class function TVariationPDJ.GetVariableNameAt(const Index: integer): string;
+begin
+  case Index Of
+  0: Result := 'pdj_a';
+  1: Result := 'pdj_b';
+  2: Result := 'pdj_c';
+  3: Result := 'pdj_d';
+  else
+    Result := '';
+  end
+end;
+
+///////////////////////////////////////////////////////////////////////////////
+function TVariationPDJ.SetVariable(const Name: string; var value: double): boolean;
+begin
+  Result := False;
+  if Name = 'pdj_a' then begin
+    FA := Value;
+    Result := True;
+  end else if Name = 'pdj_b' then begin
+    FB := Value;
+    Result := True;
+  end else if Name = 'pdj_c' then begin
+    FC := Value;
+    Result := True;
+  end else if Name = 'pdj_d' then begin
+    FD := Value;
+    Result := True;
+  end 
+end;
+
+///////////////////////////////////////////////////////////////////////////////
+class function TVariationPDJ.GetNrVariables: integer;
+begin
+  Result := 4
+end;
+
+///////////////////////////////////////////////////////////////////////////////
+function TVariationPDJ.GetVariable(const Name: string; var value: double): boolean;
+begin
+  Result := False;
+  if Name = 'pdj_a' then begin
+    Value := FA;
+    Result := True;
+  end else if Name = 'pdj_b' then begin
+    Value := FB;
+    Result := True;
+  end else if Name = 'pdj_c' then begin
+    Value := FC;
+    Result := True;
+  end else if Name = 'pdj_d' then begin
+    Value := FD;
+    Result := True;
+  end
+end;
+
+///////////////////////////////////////////////////////////////////////////////
+initialization
+  RegisterVariation(TVariationPDJ);
+end.