'任意の角度に画像を回転する
'DestPicture ：転送先のHDC(例：Picture1.hDC)
'SrcPicture ：転送元HDC
'PictureWidth ：横幅
'PictureHeight ：縦幅
'Angle ：角度

Public Sub Rotate _
　　(DestPicture As Long, _
　　SrcPicture As Long, _
　　PictureWidth As Long, _
　　PictureHeight As Long, _
　　Angle As Integer)

　　Dim i As Integer, j As Integer
　　Dim x As Single, y As Single '処理するピクセル位置(転送先)
　　Dim x_2 As Single, y_2 As Single '処理するピクセル位置(転送元)
　　Dim x_3 As Single, y_3 As Single
　　Dim x_temp As Single, y_temp As Single
　　Dim x_temp2 As Single, y_temp2 As Single
　　Dim Center As Single: Center = PictureWidth / 2

　　x = ((0 - Center) * Cos(Pi * Angle) - (0 - Center) * Sin(Pi * Angle))
　　y = ((0 - Center) * Sin(Pi * Angle) + (0 - Center) * Cos(Pi * Angle))

　　x_temp = ((1 - Center) * Cos(Pi * Angle) - (0 - Center) * Sin(Pi * Angle))
　　y_temp = ((1 - Center) * Sin(Pi * Angle) + (0 - Center) * Cos(Pi * Angle))
　　x_temp2 = ((0 - Center) * Cos(Pi * Angle) - (1 - Center) * Sin(Pi * Angle))
　　y_temp2 = ((0 - Center) * Sin(Pi * Angle) + (1 - Center) * Cos(Pi * Angle))

　　x_temp = x_temp - x
　　y_temp = y_temp - y
　　x_temp2 = x_temp2 - x
　　y_temp2 = y_temp2 - y

　　For j = 0 To PictureHeight
　　　　x_2 = x_temp2 * j + x
　　　　y_2 = y_temp2 * j + y
　　　　For i = 0 To PictureWidth
　　　　　　x_3 = x_temp * i + x_2 + Center
　　　　　　y_3 = y_temp * i + y_2 + Center
　　　　　　Call BitBlt(DestPicture, i, j, 1, 1, SrcPicture, x_3, y_3, SRCCOPY)
　　　　Next
　　Next
End Sub