tdevdraw: fake dpi calculation on Mac - plan9port - [fork] Plan 9 from user space
HTML git clone git://src.adamsgaard.dk/plan9port
DIR Log
DIR Files
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DIR README
DIR LICENSE
---
DIR commit 58b1904e3eec4d80a9a30e4267d902b523351aec
DIR parent cc9547960e7cf12129e84c9489eb5dcd6235144b
HTML Author: Russ Cox <rsc@swtch.com>
Date: Sun, 25 Nov 2012 23:55:27 -0500
devdraw: fake dpi calculation on Mac
R=rsc
http://codereview.appspot.com/6782115
Diffstat:
M src/cmd/devdraw/cocoa-screen.m | 8 ++++++++
1 file changed, 8 insertions(+), 0 deletions(-)
---
DIR diff --git a/src/cmd/devdraw/cocoa-screen.m b/src/cmd/devdraw/cocoa-screen.m
t@@ -396,6 +396,14 @@ initimg(void)
[win.img setSize: ptsize];
win.topixelscale = size.width / ptsize.width;
win.topointscale = 1.0f / win.topixelscale;
+
+ // NOTE: This is not really the display DPI.
+ // On retina, topixelscale is 2; otherwise it is 1.
+ // This formula gives us 220 for retina, 110 otherwise.
+ // That's not quite right but it's close to correct.
+ // http://en.wikipedia.org/wiki/List_of_displays_by_pixel_density#Apple
+ displaydpi = win.topixelscale * 110;
+
return i;
}