OLED displays driven by SSD1306 drivers only natively support in hard ware 0 degree and 180 degree rendering. This feature is done in software and not free. Using this feature will increase the time to calculate what data to send over i2c to the OLED. If you are strapped for cycles, this can cause keycodes to not register. In testing however, the rendering time on an `atmega32u4` board only went from 2ms to 5ms and keycodes not registering was only noticed once we hit 15ms.
90 Degree Rotated Rendering is achieved by using bitwise operations to rotate each 8 block of memory and uses two precalculated arrays to remap buffer memory to OLED memory. The memory map defines are precalculated for remap performance and are calculated based on the OLED Height, Width, and Block Size. For example, in the default 128x32 implementation we have a 64 byte block size. This gives us eight 8 byte blocks that need to be rotated and rendered. The OLED renders horizontally two 8 byte blocks before moving down a page, e.g:
90 Degree Rotated Rendering is achieved by using bitwise operations to rotate each 8 block of memory and uses two precalculated arrays to remap buffer memory to OLED memory. The memory map defines are precalculated for remap performance and are calculated based on the OLED Height, Width, and Block Size. For example, in the 128x32 implementation with a `uint8_t` block type, we have a 64 byte block size. This gives us eight 8 byte blocks that need to be rotated and rendered. The OLED renders horizontally two 8 byte blocks before moving down a page, e.g:
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@ -133,14 +143,22 @@ So those precalculated arrays just index the memory offsets in the order in whic
## OLED API
```C++
// Initialize the OLED display, rotating the rendered output 180 degrees if true.