X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=mix_effect.h;h=4ef62fe9a2454c4754635fd62566e93bbb63a96b;hp=c6739653b398b7cd9791af5361d32197dd3d8499;hb=37f56fcbe571b2322243f6de59494bf9e0cbb37a;hpb=b10c546f579c7ccb5939161e61a71cd18a3f9bbd

diff --git a/mix_effect.h b/mix_effect.h
index c673965..4ef62fe 100644
--- a/mix_effect.h
+++ b/mix_effect.h
@@ -4,6 +4,8 @@
 // Combine two images: a*x + b*y. If you set a within [0,1] and b=1-a,
 // you will get a fade; if not, you may get surprising results (consider alpha).
 
+#include <string>
+
 #include "effect.h"
 
 class MixEffect : public Effect {
@@ -15,6 +17,10 @@ public:
 	virtual bool needs_srgb_primaries() const { return false; }
 	virtual unsigned num_inputs() const { return 2; }
 
+	// TODO: In the common case where a+b=1, it would be useful to be able to set
+	// alpha_handling() to INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK. However, right now
+	// we have no way of knowing that at instantiation time.
+
 private:
 	float strength_first, strength_second;
 };