GDS cells: PIXEL_A = panel a (colour-class rectangles), SENSOR_B = panel b (sensor structure)
Units: um. Panel width = 45 um. Panel b uses the same um/px as panel a (assumption).
GDS layer numbers (datatype 0) -> names:
   1: A YELLOW  (192 shapes)
   2: A ORANGE  (304 shapes)
   3: A GREEN  (75 shapes)
   4: A CYAN  (3 shapes)
   5: A BLUE  (45 shapes)
   6: A MAGENTA  (98 shapes)
   7: A RED  (482 shapes)
   8: A WHITE  (602 shapes)
  21: B TOPMETAL (sensor region)  (1 shapes)
  22: B GUARD_RING (approx.)  (3 shapes)
  23: B DIODE (circle)  (1 shapes)
  24: B PAD (small square)  (1 shapes)
  25: B BLOCK (inner square)  (1 shapes)