Keskustelu: Koodit: VB6: StretchBlt

'tavallista kuvan venyttelyä varten
Private Declare Function StretchBlt Lib "gdi32" (ByVal hdc As Long, ByVal X As Long, ByVal Y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal nSrcWidth As Long, ByVal nSrcHeight As Long, ByVal dwRop As Long) As Long
'näiden avulla sitten saadaankin jo parempi kuvanlaatu.
Private Declare Function SetStretchBltMode Lib "gdi32" (ByVal hdc As Long, ByVal hStretchMode As Long) As Long
Const STRETCHMODE = vbPaletteModeNone

Public Sub Zoomaa()

Dim z As Long

'tämän avulla saadaan parannettua kuvan laatua.
'jotta näet eron, kokeile ensin vain alemmalla rivillä ja sitten kummillakin.
z = SetStretchBltMode(Form1.Suurennettu.hdc, STRETCHMODE)
'kopsaus ja zoomaus.
z = StretchBlt(Form1.Suurennettu.hdc, 1, 1, 50, 50, Form1.Alkuperainen.hdc, 0, 0, 100, 100, vbSrcCopy)

End Sub