sub-pixel rendering test application

[totaam]

Issue migrated from trac ticket # 1580

component: core | priority: major | resolution: fixed

2017-07-14 17:04:51: antoine created the issue

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Follow up from #559.

The same way that #1553 provided a test application for #1309 (image depth settings), we should provide test applications for sub-pixel rendering.

[totaam]

2017-07-20 17:48:29: antoine changed status from new to assigned

[totaam]

2017-08-03 17:26:31: antoine uploaded file fontrendering.png (75.3 KiB)

screenshot of the new fontrendering test application

[totaam]

2017-08-03 17:34:51: antoine uploaded file fontrendering-win32.png (62.4 KiB)

test app running on win32

[totaam]

2017-08-03 17:54:55: antoine commented

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r16604 adds a test application (very slow to run..), which looks like this on Linux (with or without xpra):
[[Image(fontrendering.png)]]

The right hand side shows the difference between the antialias setting shown on the left and the "NONE" setting.

So far it shows that I am unable to force sub-pixel rendering to turn on, only gray (which is the default is seems).

Interestingly, it does enable sub-pixel rendering on MS Windows where the colours are clearly visible on the deltas:
[[Image(fontrendering-win32.png)]]
Looks like it uses more blue on the right hand side, and orange (red) on the left. So this would imply an RGB sub-pixel order which is correct. (this inverted since we XOR the two images!)
And this is confirmed by the value retrieved through the API, see Native_GUI.exe output.

[totaam]

2017-08-10 16:45:23: antoine changed status from assigned to closed

[totaam]

2017-08-10 16:45:23: antoine set resolution to fixed