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Fix galaxy hue calculation

pull/1295/head
Andrew Tribick 2022-01-01 11:25:45 +01:00 committed by ajtribick
parent 33116aad4a
commit 4a9403ecf5
1 changed files with 4 additions and 3 deletions
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7
src/celengine/galaxy.cpp
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@ -115,12 +115,13 @@ void galaxyTextureEval(float u, float v, float /*w*/, std::uint8_t *pixel)
void colorTextureEval(float u, float /*v*/, float /*w*/, std::uint8_t *pixel)
{
unsigned int i = static_cast<unsigned int>((static_cast<float>(u)*0.5f + 0.5f)*255.99f); // [-1, 1] -> [0, 255]
int i = static_cast<int>((u * 0.5f + 0.5f) * 255.99f); // [-1, 1] -> [0, 255]
// generic Hue profile as deduced from true-color imaging for spirals
// Hue in degrees
float hue = 25.0f * std::tanh(0.0615f * (27.0f - static_cast<float>(i)));
if (i >= 28) hue += 220.0f;
float hue = (i < 28)
? 25.0f * std::tanh(0.0615f * static_cast<float>(27 - i))
: 245.0f;
//convert Hue to RGB
float r, g, b;
DeepSkyObject::hsv2rgb(&r, &g, &b, hue, 0.20f, 1.0f);