Visual Basic.NET How to Program (PDF)

Chapter 16 Graphics and Multimedia 723
132 ' account for new row tile color switch
133 light = Not light
134 Next ' next row
135
136 End Sub ' ResetBoard
137
138 ' display board in form OnPaint event
139 Protected Overrides Sub OnPaint(ByVal paintEvent _
140 As PaintEventArgs)
141
142 ' obtain graphics object
143 Dim graphicsObject As Graphics = paintEvent.Graphics
144 Dim row, column As Integer
145
146 For row = 0 To mBoard.GetUpperBound(0)
147
148 For column = 0 To mBoard.GetUpperBound(1)
149
150 ' draw image specified in board array
151 graphicsObject.DrawImage( _
152 CType(mChessTile(mBoard(row, column)), _
153 Image), New Point(TILESIZE * column, _
154 TILESIZE * row))
155 Next
156
157 Next
158
159 End Sub ' OnPaint
160
161 ' return index of piece that intersects point
162 ' optionally exclude a value
163 Private Function CheckBounds(ByVal point As Point, _
164 Optional ByVal exclude As Integer = -1) As Integer
165
166 Dim rectangle As Rectangle ' current bounding rectangle
167 Dim i As Integer
168
169 For i = 0 To mChessPieces.Count - 1
170
171 ' get piece rectangle
172 rectangle = Getpiece(i).LocationRectangle()
173
174 ' check if rectangle contains point
175 If (rectangle.Contains(point) AndAlso i exclude) Then
176 Return i
177 End If
178
179 Next
180
181 Return -1
182 End Function ' CheckBounds
183
Fig. 16.26 Chess-game code (part 4 of 9).