阶段性完成

Assets/OtherPlugins/Le Tai's Asset/TranslucentImage/Resources/Shaders/interop_birp.cginc

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+// Copyright (c) Le Loc Tai <leloctai.com> . All rights reserved. Do not redistribute.
+
+#include <UnityCG.cginc>
+
+// This need to be a macro since the type of tex can change :(
+#define SAMPLE_SCREEN_TEX(tex, uv) UNITY_SAMPLE_SCREENSPACE_TEXTURE(tex, UnityStereoTransformScreenSpaceTex(uv))
+
+// This piecewise approximation has a precision better than 0.5 / 255 in gamma space over the [0..255] range
+// i.e. abs(l2g_exact(g2l_approx(value)) - value) < 0.5 / 255
+// It is much more precise than GammaToLinearSpace but remains relatively cheap
+half3 UIGammaToLinearShim(half3 value)
+{
+    half3 low = 0.0849710 * value - 0.000163029;
+    half3 high = value * (value * (value * 0.265885 + 0.736584) - 0.00980184) + 0.00319697;
+
+    // We should be 0.5 away from any actual gamma value stored in an 8 bit channel
+    const half3 split = (half3)0.0725490; // Equals 18.5 / 255
+    return (value < split) ? low : high;
+}