I'm using the Cairo graphics library in VB6 to work with PDFs by converting them to images for easier manipulation. My goal is to resize these images to a specific maximum width and height without losing the ability to view all details. However, I'm struggling with the resizing function using Cairo in VB6. Here's my attempt:
I'm not sure how to properly use the Cairo library for resizing images. Assistance in correcting my approach would be appreciated.Code:Public Function Resize(ByRef srf As cCairoSurface, ByVal uMaxWidth As Long, ByVal uMaxHeight As Long) As cCairoSurface Dim lNewWidth As Long Dim lNewHeight As Long ' Save original image for comparison srf.WriteContentToPngFile "d:\path\before_resize.png" (looks as expected) ' Calculate new dimensions ScaleImage srf.Width, srf.Height, uMaxWidth, uMaxHeight, lNewWidth, lNewHeight, scaleDownAsNeeded ' Create new resized image Dim nNew As cCairoSurface Set nNew = srf.CreateSimilar(CAIRO_CONTENT_COLOR_ALPHA, lNewWidth, lNewHeight, False) Dim Ctx As cCairoContext Set Ctx = nNew.CreateContext() ' Fill background (testing purposes) Ctx.SetSourceRGBA 1, 0.5, 1, 0.5 (creates a pink surface as expected) Ctx.Rectangle 0, 0, lNewWidth, lNewHeight Ctx.Fill ' Attempt to render resized content srf.CreateContext.RenderSurfaceContent nNew, 0, 0, 200, 200, CAIRO_FILTER_BEST, 0.5 (does not have any effect) ' Save resized image for comparison nNew.WriteContentToPngFile "d:\path\after_resize.png" 'shows a pink image only. ' Need assistance correcting my approach. End Function




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