Improve display driver sample for very small monochrome displays #67090
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Rounding errors due to the division of non-integrally divisible buffer sizes lead to the loss of one byte. This can be avoided with the DIV_ROUND_UP() macro. Signed-off-by: Stephan Linz <linz@li-pro.net>
In exceptional cases, monochrome displays can deviate from the general interpretation (PIXEL_FORMAT_MONO01) of a logical 1 as pixel on (white) and 0 as pixel off (black) and instead set the capability to PIXEL_FORMAT_MONO10. This small but significant difference has been ignored so far, resulting in an inverse display for those displays. In order to be technically correct here, the buffers for a "white" background should be set to 0 instead of 1 and for "black" to 1 instead of 0. Signed-off-by: Stephan Linz <linz@li-pro.net>
With extremely small displays (much smaller than 64x24), the calculation of the blocks in the four corners fails. These might then be too large and no longer fit into the available area of the small displays. Signed-off-by: Stephan Linz <linz@li-pro.net>
jfischer-no
approved these changes
Jan 9, 2024
kartben
approved these changes
Jan 12, 2024
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The current implementation of
samples/drivers/displayis good enough for colorful LCD or OLED displays with standard resolution, e.g. 128x64 or larger. But in case of monochromatic or RGB colorful LED panels with very small resolution (below 64x24 or down to 3x3), the internal calculation will fail. Then it results in wrong dimensions or scaling values for the rendered blocks in the corners (TOP/BOTTOM, LEFT/RIGHT).This PR will also deal with these display types, so anyone can use this example as an initial evaluation example for the full range of possible displays in the wild.