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-rw-r--r--src/utility/Math.h23
1 files changed, 23 insertions, 0 deletions
diff --git a/src/utility/Math.h b/src/utility/Math.h
index e8d190c7..314e4e37 100644
--- a/src/utility/Math.h
+++ b/src/utility/Math.h
@@ -1,10 +1,33 @@
#pragma once
#include <cstdint>
+#include <concepts>
namespace Pinetime {
namespace Utility {
// returns the arcsin of `arg`. asin(-32767) = -90, asin(32767) = 90
int16_t Asin(int16_t arg);
+
+ // Round half away from zero integer division
+ // If T signed, divisor cannot be std::numeric_limits<T>::min()
+ // Adapted from https://github.com/lucianpls/rounding_integer_division
+ // Under the MIT license
+ template <std::integral T>
+ constexpr T RoundedDiv(T dividend, T divisor) {
+ bool neg = divisor < 0;
+ if (neg) {
+ // overflows if divisor is minimum value for T
+ divisor = -divisor;
+ }
+
+ T m = dividend % divisor;
+ T h = divisor / 2 + divisor % 2;
+ T res = (dividend / divisor) + (!(dividend < 0) & (m >= h)) - ((dividend < 0) & ((m + h) <= 0));
+
+ if (neg) {
+ res = -res;
+ }
+ return res;
+ }
}
}