X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=gamma_expansion_effect.cpp;h=d4e532f8b816f1cf594a0f82ba199f5133f944cb;hp=cef1416ae5b8f7f5c7f9fc8c74641c11927412ef;hb=0dc1dfe6444a700ebd2c9f006cba000b90c3a7b0;hpb=93b0136eb2bd31043526b95dc3e920bc2ab880ee

diff --git a/gamma_expansion_effect.cpp b/gamma_expansion_effect.cpp
index cef1416..d4e532f 100644
--- a/gamma_expansion_effect.cpp
+++ b/gamma_expansion_effect.cpp
@@ -1,7 +1,44 @@
+#include <math.h>
+#include <assert.h>
+
 #include "gamma_expansion_effect.h"
+#include "util.h"
 
 GammaExpansionEffect::GammaExpansionEffect()
 	: source_curve(GAMMA_LINEAR)
 {
 	register_int("source_curve", (int *)&source_curve);
+	register_1d_texture("expansion_curve_tex", expansion_curve, EXPANSION_CURVE_SIZE);
+}
+
+std::string GammaExpansionEffect::output_fragment_shader()
+{
+	if (source_curve == GAMMA_LINEAR) {
+		return read_file("identity.frag");
+	}
+	if (source_curve == GAMMA_sRGB) {
+		for (unsigned i = 0; i < EXPANSION_CURVE_SIZE; ++i) {
+			float x = i / (float)(EXPANSION_CURVE_SIZE - 1);
+			if (x < 0.04045f) {
+				expansion_curve[i] = (1.0/12.92f) * x;
+			} else {
+				expansion_curve[i] = pow((x + 0.055) * (1.0/1.055f), 2.4);
+			}
+		}
+		invalidate_1d_texture("expansion_curve_tex");
+		return read_file("gamma_expansion_effect.frag");
+	}
+	if (source_curve == GAMMA_REC_709) {  // And Rec. 601.
+		for (unsigned i = 0; i < EXPANSION_CURVE_SIZE; ++i) {
+			float x = i / (float)(EXPANSION_CURVE_SIZE - 1);
+			if (x < 0.081f) {
+				expansion_curve[i] = (1.0/4.5f) * x;
+			} else {
+				expansion_curve[i] = pow((x + 0.099) * (1.0/1.099f), 1.0f/0.45f);
+			}
+		}
+		invalidate_1d_texture("expansion_curve_tex");
+		return read_file("gamma_expansion_effect.frag");
+	}
+	assert(false);
 }