anchor.diff:      function GetDainParams(aDir: string; aAlpha: Boolean): string;
   
       procedure WriteEmptyAnim;
  -    procedure MakeInterpImagesPair(RT: TRXType; aID_1, aID_2, aID_1_Base, aID_2_Base: Integer; aBaseMoveX, aBaseMoveY: Integer; aBaseDir: string; aExportType: TInterpExportType);
  +    procedure MakeInterpImagesPair(RT: TRXType; aID_1, aID_2, aID_1_Base, aID_2_Base: Integer; aBaseMoveX, aBaseMoveY: Integer; aUseBase: Boolean; aBaseDir: string; aExportType: TInterpExportType);
       procedure DoInterp(RT: TRXType; A, ABase: TKMAnimLoop; aUseBase, aUseBaseForTeamMask, aSimpleAlpha: Boolean; aBkgRGB: Cardinal; var aPicOffset: Integer; aDryRun: Boolean);
       procedure DoInterpUnit(aUT: TKMUnitType; aAction: TKMUnitActionType; aDir: TKMDirection; var aPicOffset: Integer; aDryRun: Boolean);
       procedure DoInterpSerfCarry(aWare: TKMWareType; aDir: TKMDirection; var aPicOffset: Integer; aDryRun: Boolean);
  
positive.code:     CanvasSize := Max(CanvasSize, GetCanvasSize(aID_1_Base, RT, aBaseMoveX, aBaseMoveY));
    if aID_2_Base >= 0 then
      CanvasSize := Max(CanvasSize, GetCanvasSize(aID_2_Base, RT, aBaseMoveX, aBaseMoveY));
  
    Worked := fSprites[RT].ExportImageForInterp(origSpritesDir + '1.png', aID_1, aID_1_Base, aBaseMoveX, aBaseMoveY, aExportType, CanvasSize);
    AllBlank := AllBlank and not Worked;
  
negative.code:     BaseMoveY := ABase.MoveY - A.MoveY;
  
      if aSimpleAlpha then
        MakeInterpImagesPair(RT, StepSprite, StepNextSprite, StepSpriteBase, StepNextSpriteBase, BaseMoveX, BaseMoveY, True, dirBase, ietNormal)
      else
      begin
        MakeInterpImagesPair(RT, StepSprite, StepNextSprite, StepSpriteBase, StepNextSpriteBase, BaseMoveX, BaseMoveY, True, dirBase, ietBase);
        MakeInterpImagesPair(RT, StepSprite, StepNextSprite, StepSpriteBase, StepNextSpriteBase, BaseMoveX, BaseMoveY, True, dirShad, ietShadows);
        MakeInterpImagesPair(RT, StepSprite, StepNextSprite, StepSpriteBase, StepNextSpriteBase, BaseMoveX, BaseMoveY, aUseBaseForTeamMask, dirTeam, ietTeamMask);
      end;
  
      //Determine maximum bounds of the pair, to crop out the base background sprite
  