unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, DIB, StdCtrls;

type
  TForm1 = class(TForm)
    DXPaintBox1: TDXPaintBox;
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    procedure DXPaintBox1MouseMove(Sender: TObject; Shift: TShiftState; X,
      Y: Integer);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

var
  dib: TDIB;

procedure TForm1.DXPaintBox1MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
var
  a: TLightArray;
begin
  DXPaintBox1.DIB.Assign(dib);
  SetLength(a, 1);
  a[0].X := X;
  a[0].Y := Y;
  a[0].Size1 := 4;
  a[0].Size2 := 4;
  a[0].Color := clWhite;

  DXPaintBox1.DIB.InitLight(1, 1);
  DXPaintBox1.DIB.DrawLights(a, clBlack);
  DXPaintBox1.Repaint;
end;

procedure TForm1.FormCreate(Sender: TObject);
const
  ImgPath1 = 'C:\Temp\DX.jpg';
begin
  dib := TDIB.Create;
  dib.LoadFromFile(ImgPath1);
  DXPaintBox1.DIB.Assign(dib);
  DXPaintBox1.Width := dib.Width;
  DXPaintBox1.Height := dib.Height;
  DXPaintBox1.Repaint;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  dib.Free;
end;

end.

object Form1: TForm1
  Left = 0
  Top = 0
  Caption = 'Form1'
  ClientHeight = 142
  ClientWidth = 177
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  OnCreate = FormCreate
  OnDestroy = FormDestroy
  PixelsPerInch = 96
  TextHeight = 13
  object DXPaintBox1: TDXPaintBox
    Left = 8
    Top = 8
    Width = 129
    Height = 126
    AutoStretch = False
    Center = False
    KeepAspect = False
    Stretch = False
    ViewWidth = 0
    ViewHeight = 0
    OnMouseMove = DXPaintBox1MouseMove
  end
end