X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=gamma_expansion_effect.h;h=043731baf15ef48c8812d1ec6fb6e5234a5b87a3;hp=f079e7085f6e7ba6f6721f8aa3142e9ddb2f88e6;hb=fc55857d9ccf1edcc141fa0853a8bf2d6b40b4dc;hpb=2ced784c6599cb0b21427481ee17f4c8f6afdada

diff --git a/gamma_expansion_effect.h b/gamma_expansion_effect.h
index f079e70..043731b 100644
--- a/gamma_expansion_effect.h
+++ b/gamma_expansion_effect.h
@@ -1,18 +1,33 @@
 #ifndef _GAMMA_EXPANSION_EFFECT_H 
 #define _GAMMA_EXPANSION_EFFECT_H 1
 
+// An effect to convert the given gamma curve into linear light,
+// typically inserted by the framework automatically at the beginning
+// of the processing chain.
+//
+// Currently supports sRGB and Rec. 601/709.
+
 #include "effect.h"
 #include "effect_chain.h"
 
 #define EXPANSION_CURVE_SIZE 256
 
 class GammaExpansionEffect : public Effect {
-public:
+private:
+	// Should not be instantiated by end users.
 	GammaExpansionEffect();
+	friend class EffectChain;
+
+public:
+	virtual std::string effect_type_id() const { return "GammaExpansionEffect"; }
 	std::string output_fragment_shader();
 
-	virtual bool needs_linear_light() { return false; }
-	virtual bool needs_srgb_primaries() { return false; }
+	virtual bool needs_linear_light() const { return false; }
+	virtual bool needs_srgb_primaries() const { return false; }
+
+	// Actually processes its input in a nonlinear fashion,
+	// but does not touch alpha, and we are a special case anyway.
+	virtual AlphaHandling alpha_handling() const { return DONT_CARE_ALPHA_TYPE; }
 
 private:
 	GammaCurve source_curve;