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@@ -188,13 +188,22 @@ static _FORCE_INLINE_ unsigned int nearest_power_of_2(unsigned int x) {
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return ++x;
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}
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+// We need this definition inside the function below.
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+static inline int get_shift_from_power_of_2(unsigned int p_pixel);
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+
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template<class T>
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static _FORCE_INLINE_ T nearest_power_of_2_templated(T x) {
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--x;
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+
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+ // The number of operations on x is the base two logarithm
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+ // of the p_number of bits in the type. Add three to account
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+ // for sizeof(T) being in bytes.
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+ size_t num = get_shift_from_power_of_2(sizeof(T)) + 3;
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+
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// If the compiler is smart, it unrolls this loop
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// If its dumb, this is a bit slow.
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- for (size_t i = 0; i < sizeof(T); i++)
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+ for (size_t i = 0; i < num; i++)
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x |= x >> (1 << i);
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return ++x;
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