Files
Upsilon/kandinsky/src/postprocess_gamma_context.cpp
2019-11-01 19:44:53 +01:00

86 lines
3.1 KiB
C++

#include <kandinsky/postprocess_gamma_context.h>
#include <ion.h>
#include <math.h>
constexpr int MaxGammaStates = 7;
constexpr float MaxGammaGamut = 0.75;
constexpr float toGamma(int gamma) {
return 1.f / (1 + (float(gamma) / MaxGammaStates * MaxGammaGamut));
}
constexpr int clampGamma(int gamma) {
return gamma < -MaxGammaStates ? -MaxGammaStates : (gamma > MaxGammaStates ? MaxGammaStates : gamma);
}
KDPostProcessGammaContext::KDPostProcessGammaContext() :
m_redGamma(0), m_greenGamma(0), m_blueGamma(0) {}
void KDPostProcessGammaContext::gamma(int& red, int& green, int& blue) {
red = m_redGamma;
green = m_greenGamma;
blue = m_blueGamma;
}
void KDPostProcessGammaContext::gamma(float& red, float& green, float& blue) {
red = (m_redGamma + MaxGammaStates) / float(MaxGammaStates*2);
green = (m_greenGamma + MaxGammaStates) / float(MaxGammaStates*2);
blue = (m_blueGamma + MaxGammaStates) / float(MaxGammaStates*2);
}
void KDPostProcessGammaContext::setGamma(int red, int green, int blue) {
m_redGamma = clampGamma(red);
m_greenGamma = clampGamma(green);
m_blueGamma = clampGamma(blue);
}
void KDPostProcessGammaContext::pushRect(KDRect rect, const KDColor * pixels) {
const float redGamma = toGamma(m_redGamma);
const float greenGamma = toGamma(m_greenGamma);
const float blueGamma = toGamma(m_blueGamma);
KDColor workingBuffer[rect.width()];
for (KDCoordinate y = 0; y < rect.height(); y++) {
KDRect workingRect(rect.x(), rect.y()+y, rect.width(), 1);
for (KDCoordinate x = 0; x < rect.width(); x++) {
const KDColor color = pixels[y*rect.width()+x];
const KDColor result = KDColor::RGB888(
(uint8_t)(powf(color.red()/255.f, redGamma)*255),
(uint8_t)(powf(color.green()/255.f, greenGamma)*255),
(uint8_t)(powf(color.blue()/255.f, blueGamma)*255));
workingBuffer[x] = result;
}
KDPostProcessContext::pushRect(workingRect, workingBuffer);
}
}
void KDPostProcessGammaContext::pushRectUniform(KDRect rect, KDColor color) {
const float redGamma = toGamma(m_redGamma);
const float greenGamma = toGamma(m_greenGamma);
const float blueGamma = toGamma(m_blueGamma);
const KDColor result = KDColor::RGB888(
(uint8_t)(powf(color.red()/255.f, redGamma)*255),
(uint8_t)(powf(color.green()/255.f, greenGamma)*255),
(uint8_t)(powf(color.blue()/255.f, blueGamma)*255));
KDPostProcessContext::pushRectUniform(rect, result);
}
void KDPostProcessGammaContext::pullRect(KDRect rect, KDColor * pixels) {
const float redGamma = 1.f/toGamma(m_redGamma);
const float greenGamma = 1.f/toGamma(m_greenGamma);
const float blueGamma = 1.f/toGamma(m_blueGamma);
KDPostProcessContext::pullRect(rect, pixels);
for (KDCoordinate y = 0; y < rect.height(); y++) {
for (KDCoordinate x = 0; x < rect.width(); x++) {
const KDColor color = pixels[y*rect.width()+x];
const KDColor result = KDColor::RGB888(
(uint8_t)(powf(color.red()/255.f, redGamma)*255),
(uint8_t)(powf(color.green()/255.f,greenGamma)*255),
(uint8_t)(powf(color.blue()/255.f, blueGamma)*255));
pixels[y*rect.width()+x] = result;
}
}
}