diff --git a/src/helpers/BezierCurve.cpp b/src/helpers/BezierCurve.cpp index 9c8fc514..e79863a3 100644 --- a/src/helpers/BezierCurve.cpp +++ b/src/helpers/BezierCurve.cpp @@ -48,27 +48,25 @@ float CBezierCurve::getXForT(float t) { // Todo: this probably can be done better and faster float CBezierCurve::getYForPoint(float x) { - if (x >= 1.0) - return 1.0; + if (x >= 1.f) + return 1.f; - // binary search for the range UPDOWN X - int upperT = BAKEDPOINTS - 1; - int lowerT = 0; - int mid = upperT / 2; + int index = 0; + bool below = true; + for (int step = (BAKEDPOINTS + 1) / 2; step > 0; step /= 2) { + if (below) + index += step; + else + index -= step; - while (std::abs(upperT - lowerT) > 1) { - if (m_aPointsBaked[mid].x > x) { - upperT = mid; - } else { - lowerT = mid; - } - - mid = (upperT + lowerT) / 2; + below = m_aPointsBaked[index].x < x; } + int lowerIndex = index - (!below || index == BAKEDPOINTS - 1); + // in the name of performance i shall make a hack - const auto LOWERPOINT = &m_aPointsBaked[std::clamp(lowerT, 0, BAKEDPOINTS - 1)]; - const auto UPPERPOINT = &m_aPointsBaked[std::clamp(upperT, 0, BAKEDPOINTS - 1)]; + const auto LOWERPOINT = &m_aPointsBaked[lowerIndex]; + const auto UPPERPOINT = &m_aPointsBaked[lowerIndex + 1]; const auto PERCINDELTA = (x - LOWERPOINT->x) / (UPPERPOINT->x - LOWERPOINT->x); @@ -76,4 +74,4 @@ float CBezierCurve::getYForPoint(float x) { return 0.f; return LOWERPOINT->y + (UPPERPOINT->y - LOWERPOINT->y) * PERCINDELTA; -} \ No newline at end of file +}