Minimalist SSD1306 Display Library

Reduce footprint to under 9k for basic sample and make it compatible with Adafruit_SSD1306 for graphics API as a fallback.

For ATmega328p only.

No scrolling functions, no display rotation, all configuration is through macros, ATmega328p TWI library for display communication. Function argument types reduced to minimum and number of arguments reduced by having X & Y cursors for the current pixel position.

The library supports:

• WHITE, BLACK, INVERT, NONE colors

• patterned lines, upto 8 bit line pattern, disabled via GFX_NO_LINE_PATTERNS definition which reduces memory footprint by 420 bytes.

• filled and unfilled rectangles, rounded rectangles, circles

• 5x7 96 character ASCII font,

• double width and/or double height characters

• optional tiny 3x5 character font for digits, enabled by GFX_SMALL_FONT, adds 360 bytes to memory use. Of the 360 bytes, 204 bytes is font data and 156 is overhead shared with GFX_LARGE_FONTS option.
  

• optional character based font substitution for double height double width characters for digits, enabled by GFX_LARGE_FONT, adds 690 bytes to memory use. Of the 690 bytes, 534 bytes is font data and 156 is overhead shared with GFX_SMALL_FONTS option.
  vs

• optional BitBlit functions for character and bitmap rendering, can be disabled via GFX_NO_BIT_BLIT definition. This reduces the memory footprint by 856 bytes if both text and bitmap rendering functions are used, and 622 bytes if only text functions are used.

  However, bit blit functions speed up rendering by a factor of 3.

  GFX_BIT_BLIT Enabled	GFX_NO_BIT_BLIT

  The numbers at the bottom of the images are uSec: Min/Avg/Max for rendering the bitmap and/or text, taken from an 8MHz arduino.