Reversi Game Implementation in Visual Basic 6

This mini version of the classic Reversi game demonstrates core programming concepts using Visual Basic 6. The implementation uses two-dimensional arrays to track game state and includes logic for validating moves and flipping pieces.

Core Game Logic

The game uses two 4×4 Boolean arrays:

white(4,4) tracks positions of white pieces
black(4,4) tracks positions of black pieces

When a piece is placed on the board, the corresponding array element is set to True. The game logic then checks adjacent positions to determine which pieces should be flipped.

Game Implementation Details

Board Representation

The game board is implemented using an array of 16 image controls arranged in a 4×4 grid. Each square is represented by an indexed image control (Image1(0) to Image1(15)).

Drag-and-Drop Mechanics

Players drag either the white or black piece image onto the board. The game validates each move to ensure it follows Reversi rules before updating the game state.

Game Logic

Using If...Then and Select Case statements, the program checks valid moves and flips trapped pieces between the newly placed piece and existing pieces of the same color.

Score Tracking

The game continuously counts and displays the number of white and black pieces. At game end, it declares the winner based on piece count.

Designing the Interface

To create the game interface:

Insert an image control and duplicate it to create a 4×4 grid
Create solid white and black circle images (saved as JPEG files)
Implement drag-and-drop functionality using the DragDrop method

Board Layout Positions

Image1(12)	Image1(13)	Image1(14)	Image1(15)
Image1(8)	Image1(9)	Image1(10)	Image1(11)
Image1(4)	Image1(5)	Image1(6)	Image1(7)
Image1(0)	Image1(1)	Image1(2)	Image1(3)

Figure 1: Image control positions on the game board

Game Interface at Runtime

Figure 2: Reversi game in action with white and black pieces

Code Implementation

The following subroutine checks the status of each position on the board:

Option Base 1
Dim white(4, 4) As Boolean
Dim black(4, 4) As Boolean
Dim i, j, k, w, b As Integer
Dim imgtag As String

' Check board status and update piece positions
Sub checkstatus()
    k = 0
    For j = 1 To 4
        For i = 1 To 4
            ' Check for white pieces
            If Image1(k).Picture = Image17.Picture Then
                white(i, j) = True
            Else
                white(i, j) = False
            End If
            
            ' Check for black pieces
            If Image1(k).Picture = Image18.Picture Then
                black(i, j) = True
            Else
                black(i, j) = False
            End If
            
            k = k + 1
        Next i
    Next j
End Sub

How the CheckStatus Subroutine Works

This procedure:

Iterates through each position on the 4×4 board
Checks if the image at each position matches the white piece image (Image17)
Updates the white array accordingly
Checks if the image matches the black piece image (Image18)
Updates the black array accordingly

Game Logic Implementation

The core game mechanics involve:

Move validation: Ensuring moves follow Reversi rules
Piece flipping: Identifying and flipping trapped pieces
Turn management: Alternating between players
Win detection: Determining when the game ends and who won

' Example of move validation logic
If ValidMove(row, col, currentPlayer) Then
    PlacePiece(row, col, currentPlayer)
    FlipPieces(row, col, currentPlayer)
    currentPlayer = IIf(currentPlayer = WHITE, BLACK, WHITE)
Else
    MsgBox "Invalid move! Please try again."
End If

Tip: The actual implementation would include more complex logic to check all eight directions around the placed piece to determine which opponent pieces are trapped between two pieces of the current player's color.