Comment 2 for bug 703191

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Clarke Wixon (cwixon) wrote :

I'm a little dismayed at the lack of action here, because Natty Alpha 2 just came out, and I verified it has exactly the same problem (following booting from the AMD64 LiveCD).

I have objectively verified my findings. There is NO DIFFERENCE between RGB-ordered font rendering and BGR-ordered font rendering in Gnome/GTK+ applications, where there absolutely should be.

I opened up a galculator window (selected because it is a static window with a variety of fine text and no blinking cursor or other distractions). With the program open and otherwise unused, I selected each of the four possible subpixel antialiasing options (RGB, BGR, VRGB, VBGR) via the Gnome appearance settings panel, in turn, and each time I captured a screenshot of just the galculator window.

I then calculated md5sums on each of the resulting PNG files.

7e9d1be5a35fb8c9e02f5744db81d765 Screenshot-galculator-bgr.png
7e9d1be5a35fb8c9e02f5744db81d765 Screenshot-galculator-rgb.png
778b69aa3eb0dee4aa6faca84eb6ee15 Screenshot-galculator-vbgr.png
f6d55d5d5fcdd6d43ad9e12547138aa0 Screenshot-galculator-vrgb.png

As you will see, the -bgr and -rgb screenshots calculate to exactly the same md5sum. THERE IS NOT A SINGLE PIXEL DIFFERENCE.

In contrast, -rgb, -vrgb, and -vbgr are all different, as expected.

Would someone mind confirming this bug? I'd like to get it fixed. Font rendering is one of the reasons I moved away from Windows more than five years ago.

I'm attaching 4x enlargements of a crop of each of the galculator window screenshots. If you look at the color fringing around the word "log," you should be able to see what I'm talking about. Between -vbgr and -vrgb, the red and blue fringes around the "o" and "g" switch between top and bottom, as expected. But with both -rgb and -bgr, the red fringes stay on the left and the blue fringes stay on the right in both cases, when they should be switching.

I don't know how much more I can say about this, so I'll leave it there and hope for some further input from a developer or maintainer.