X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=overlay_effect.h;h=29c09416ddea3f79aaf3ee733870ff66468f0b1f;hp=121027a9f891aef043a735be1a7ff004097ee1e3;hb=f8e5ddc082f2267198292ea9e53d4a8b45f7b3b1;hpb=105717071781cb6ce338760937e43af29dcb228a

diff --git a/overlay_effect.h b/overlay_effect.h
index 121027a..29c0941 100644
--- a/overlay_effect.h
+++ b/overlay_effect.h
@@ -1,5 +1,5 @@
-#ifndef _OVERLAY_EFFECT_H
-#define _OVERLAY_EFFECT_H 1
+#ifndef _MOVIT_OVERLAY_EFFECT_H
+#define _MOVIT_OVERLAY_EFFECT_H 1
 
 // Put one image on top of another, using alpha where appropriate.
 // (If both images are the same aspect and the top image has alpha=1.0
@@ -10,16 +10,35 @@
 //
 // The first input is the bottom, and the second is the top.
 
+#include <string>
+
 #include "effect.h"
 
+namespace movit {
+
 class OverlayEffect : public Effect {
 public:
 	OverlayEffect();
-	virtual std::string effect_type_id() const { return "OverlayEffect"; }
-	std::string output_fragment_shader();
+	std::string effect_type_id() const override { return "OverlayEffect"; }
+	std::string output_fragment_shader() override;
+
+	bool needs_srgb_primaries() const override { return false; }
+	unsigned num_inputs() const override { return 2; }
+	bool strong_one_to_one_sampling() const override { return true; }
 
-	virtual bool needs_srgb_primaries() const { return false; }
-	virtual unsigned num_inputs() const { return 2; }
+	// Actually, if _either_ image has blank alpha, our output will have
+	// blank alpha, too (this only tells the framework that having _both_
+	// images with blank alpha would result in blank alpha).
+	// However, understanding that would require changes
+	// to EffectChain, so postpone that optimization for later.
+	AlphaHandling alpha_handling() const override { return INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK; }
+
+private:
+	// If true, overlays input1 on top of input2 instead of vice versa.
+	// Must be set before finalize.
+	bool swap_inputs;
 };
 
-#endif // !defined(_OVERLAY_EFFECT_H)
+}  // namespace movit
+
+#endif // !defined(_MOVIT_OVERLAY_EFFECT_H)