calcBlendFactor(): templated, also a small speedup be reordering instructions

This commit is contained in:
Ingo Weyrich
2020-09-20 15:07:14 +02:00
parent 5b97e0cde3
commit cd63427eca

View File

@@ -34,23 +34,14 @@
#include "sleef.h"
namespace {
float calcBlendFactor(float val, float threshold) {
// sigmoid function
// result is in ]0;1] range
// inflexion point is at (x, y) (threshold, 0.5)
return 1.f / (1.f + xexpf(16.f - 16.f * val / threshold));
}
#ifdef __SSE2__
vfloat calcBlendFactor(vfloat valv, vfloat thresholdv) {
template<typename T>
T calcBlendFactor(T val, T threshold) {
// sigmoid function
// result is in ]0;1] range
// inflexion point is at (x, y) (threshold, 0.5)
const vfloat onev = F2V(1.f);
const vfloat c16v = F2V(16.f);
return onev / (onev + xexpf(c16v - c16v * valv / thresholdv));
return 1.f / (1.f + xexpf(16.f - (16.f / threshold) * val));
}
#endif
float tileAverage(const float * const *data, size_t tileY, size_t tileX, size_t tilesize) {