Fixing gamma correction in EEP Step 1:

Thou shall always read the sky cubemap as sRGB using hardware sampling.

1 files changed, 20 insertions, 0 deletions

diff --git a/indra/llmath/llmath.h b/indra/llmath/llmath.h
index e508c9a199..bb19248f1f 100644
--- a/indra/llmath/llmath.h
+++ b/indra/llmath/llmath.h
@@ -537,6 +537,26 @@ inline void ll_remove_outliers(std::vector<VEC_TYPE>& data, F32 k)
 	}
 }
 
+// This converts from a non-linear sRGB floating point value (0..1) to a linear value.
+// Useful for gamma correction and such.  Note: any values passed through this should not be serialized.  You should also ideally cache the output of this.
+inline float sRGBtoLinear(const float val) {
+	if (val < 0.0031308f) {
+		return val * 12.92f;
+	}
+	else {
+		return 1.055f * pow(val, 1.0f / 2.4f) - 0.055f;
+	}
+}
+
+inline float linearTosRGB(const float val) {
+	if (val < 0.04045f) {
+		return val / 12.92f;
+	}
+	else {
+		return pow((val + 0.055f) / 1.055f, 2.4f);
+	}
+}
+
 // Include simd math header
 #include "llsimdmath.h"