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Low-level Graphics on Raspberry Pi vs other Linux distributions
In the very first post on this subject I suggested the examples would apply to other systems as well - luckily I did add the caveat 'some of the code' ;) As it appears that the support for the framebuffer driver and the functionality it provides seems to in...

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Low-level Graphics on Raspberry Pi (more images)
In an earlier post we looked at converting an image to 16 bit 5:6:5 format for direct copying to framebuffer. The obvious drawback of that approach is the requirement on the image size to exactly match the display/framebuffer size (or the width at least). M...

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Modifying Ctrl+Alt+Del behavior in Debian Jessie vs Wheezy
Finally got up to testing Raspbian Jessie and being a mixed user of Linux and Windows ran into an issue with the 'three finger salute' Ctrl-Alt-Del (C-D-A) key combination. In Windows this is normally used to lock up the UI when going away from the computer...

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Low-level Graphics on Raspberry Pi (even more palette)
Another effect with palette: fade in/out. We can - in addition to rotating the entries - modify the palette entry RGB values on the fly and make the pixels drawn in this color to fade in or out. Draw some background stuff (blue and white checkerboard), a bl...

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Low-level Graphics on Raspberry Pi (more palette)
In a previous post we briefly looked at palette animation. Now (hopefully) a slightly more appetising example of what could be done with this technique. Let's draw some 'rainbow striped' blocks and customise the palette to include 16 colors sliding from red...

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Low-level Graphics on Raspberry Pi (Images)
One of the recurring themes regarding Raspberry Pi graphics is the 16-bit RGB 5:6:5 display mode vs typically 24-bit images. The '565' mode is the default on HDMI and possibly the only one available on TFT add-on displays like this one from Adafruit . There...

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Low-level Graphics on Raspberry Pi (part X+3)
Again life has happened and the time has slipped. Thanks for the response on the Raspberry Pi forum. To iterate the message from there: I have disabled comments here because I cannot guarantee any kind of decent response time, sorry. Just a quick, short one...

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Low-level Graphics on Raspberry Pi (part X update III)
Finally managed to find the cause for the (intermittent - reproducible at will only straight after boot) screen blanking issue (mentioned in previous post ): the changes in the framebuffer driver seem to require the calls to KDSETMODE to be inside the FBIOP...

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Low-level Graphics on Raspberry Pi (part X update II)
Finally... in continuation to this post , after some elaboration on the forum I managed to get down to testing this properly - it appears that the changes in the fb driver can be made to work! Replace the 'switch page' by either (ioctl version): // switch p...

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Low-level Graphics on Raspberry Pi (part X update)
BREAKING NEWS: The Raspberry Pi Linux framebuffer driver has been updated and the PAN_DISPLAY function mentioned in Part X has been added - so the smooth double-buffer page-flipping animation should now be possible without further hacks! Based on a quick te...
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