Rebecca did not know why Gawain was interested in this question, but at least her ancestor did not look like he was about to criticize her, so she breathed a sigh of relief. "I just calculated while drawing... It was much easier if I treated the whole courtyard like a sheet of paper."
That answer was far too vague. Gawain frowned slightly. "Specifically?"
"This side of the courtyard is one line, and the side next to it is another," Rebecca said, vigorously waving her arms as she gestured. "Then, using those two lines as a reference, I treated the entire courtyard like a sheet of paper. I broke every line in the Magic Array into lots of key points, and calculated the distance from each key point to the two sides of the courtyard—then I just had to enlarge the numbers from the draft. Calculations are a mage's specialty!"
Calculation was indeed a mage's specialty, but ordinary mages did not calculate like this!
Gawain stared at Rebecca in astonishment. The girl explained things in a complete mess, and Heti probably had not understood what she meant, but Gawain had: she had established a coordinate system in the courtyard, then enlarged the Magic Array from the draft proportionally based on that system.
There was no need to stand somewhere high up at all. She only needed to calculate where every key point belonged, then connect those points according to the draft.
But merely coming up with the idea was not enough. Rebecca also needed extraordinarily strong geometric visualization and mental arithmetic abilities—because this world did not possess a complete mathematical or geometric system. Either she had painstakingly built everything up through addition, subtraction, multiplication, and division, or she had invented all kinds of formulas herself!
Of course, Rebecca's method was not