MarkupLabel Control - Markup images not rendered correctly in 16.2.3

Print Page | Close Window

Markup images not rendered correctly in 16.2.3

Printed From: Codejock Forums
Category: Codejock Products
Forum Name: MarkupLabel Control
Forum Description: Topics Related to Codejock MarkupLabel Control
URL: http://forum.codejock.com/forum_posts.asp?TID=21859
Printed Date: 21 November 2024 at 1:26pm
Software Version: Web Wiz Forums 12.04 - http://www.webwizforums.com

Topic: Markup images not rendered correctly in 16.2.3

Posted By: flashk
Subject: Markup images not rendered correctly in 16.2.3
Date Posted: 25 August 2013 at 6:16pm

I just upgraded from 15.0.2 to 16.2.3 and noticed that markup controls don't render images with alpha channels correctly. I've attached a screenshot showing the difference between the two versions.

I'm using the following markup to specify the image from its resource ID (based on a 32-bit PNG):

<Image Source='1200' VerticalAlignment='Center' />

Is this a known issue? Do I need to change the markup or other setting to render the image correctly?

Replies:

Posted By: flashk
Date Posted: 12 September 2013 at 5:52pm

I believe I've found why the images are not being rendered correctly. The code for rendering markup images was changed from:

HDC hDC = pDC->GetDC();m_pImage->Draw(CDC::FromHandle(hDC), CPoint(0, 0), szRender);
pDC->ReleaseDC(hDC);

to:

pDC->DrawImage(m_pImage, CRect(0, 0, szRender.cx, szRender.cy));

This change seems to cause the image to be drawn using GDI+ instead of GDI. The CXTPMarkupGdiPlusDeviceContext class seems to draw images with alpha channels incorrectly. In CXTPMarkupGdiPlusDeviceContext::IconToGdiplusBitmap, the PixelFormat32bppARGB flag is used to create the bitmap for rendering. However, I believe the flag should be changed to PixelFormat32bppPARGB, since the CXTPImageManagerIcon object stores pre-multiplied alpha values.

Making this one change seems to fix the image rendering issues for me.

Posted By: markr
Date Posted: 13 February 2014 at 12:18am

It would be really nice to get this problem fixed in the XTP sources.

Posted By: astoyan
Date Posted: 01 July 2015 at 8:08pm

Thank you, flashk, for the suggestion. The fix has been added.

Regards,

Alexander

Posted By: markr
Date Posted: 02 July 2015 at 9:38am

> The fix has been added.

Excellent, thanks!