From 0568af7ce0112c0dfac880f552a6158f8df97c3a Mon Sep 17 00:00:00 2001
From: Rodrigo Braz Monteiro <zeratul@cellosoft.com>
Date: Tue, 3 Apr 2007 21:05:33 +0000
Subject: [PATCH] added ClampSignedInteger32() to utils and used that to remove
 branching from YV12->RGB32 conversion, hopefully making it faster. Also,
 fixed a warning in lavc audio provider.

Originally committed to SVN as r988.
---
 aegisub/audio_provider_lavc.cpp |  2 +-
 aegisub/utils.h                 | 40 +++++++++++++++++++++++++--------
 aegisub/video_frame.cpp         |  6 ++---
 3 files changed, 35 insertions(+), 13 deletions(-)

diff --git a/aegisub/audio_provider_lavc.cpp b/aegisub/audio_provider_lavc.cpp
index 60080647e..d5c468820 100644
--- a/aegisub/audio_provider_lavc.cpp
+++ b/aegisub/audio_provider_lavc.cpp
@@ -111,7 +111,7 @@ LAVCAudioProvider::LAVCAudioProvider(wxString _filename)
 	}
 #endif
 	audStream = -1;
-	for (int i = 0; i < lavcfile->fctx->nb_streams; i++) {
+	for (unsigned int i = 0; i < lavcfile->fctx->nb_streams; i++) {
 		codecContext = lavcfile->fctx->streams[i]->codec;
 		if (codecContext->codec_type == CODEC_TYPE_AUDIO) {
 			stream = lavcfile->fctx->streams[i];
diff --git a/aegisub/utils.h b/aegisub/utils.h
index 799c5bc13..6a7a930a5 100644
--- a/aegisub/utils.h
+++ b/aegisub/utils.h
@@ -57,15 +57,6 @@ void AppendBitmapMenuItem (wxMenu* parentMenu,int id,wxString text,wxString help
 int SmallestPowerOf2(int x);
 
 
-///////////
-// Inlines
-inline void IntSwap(int &a,int &b) {
-	int c = a;
-	a = b;
-	b = c;
-}
-
-
 //////////
 // Macros
 #ifndef MIN
@@ -79,3 +70,34 @@ inline void IntSwap(int &a,int &b) {
 #ifndef MID
 #define MID(a,b,c) MAX((a),MIN((b),(c)))
 #endif
+
+#ifndef FORCEINLINE
+#ifdef __VISUALC__
+#define FORCEINLINE __forceinline
+#else
+#define FORCEINLINE __attribute__((always_inline))
+#endif
+#endif
+
+
+///////////
+// Inlines
+inline void IntSwap(int &a,int &b) {
+	int c = a;
+	a = b;
+	b = c;
+}
+
+
+//////////////////////////
+// Clamp integer to range
+// Code taken from http://bob.allegronetwork.com/prog/tricks.html#clamp
+FORCEINLINE int ClampSignedInteger32(int x,int min,int max) {
+	x -= min;
+	x &= (~x) >> 31;
+	x += min;
+	x -= max;
+	x &= x >> 31;
+	x += max;
+	return x;
+}
diff --git a/aegisub/video_frame.cpp b/aegisub/video_frame.cpp
index d9cc248e0..2b26a5612 100644
--- a/aegisub/video_frame.cpp
+++ b/aegisub/video_frame.cpp
@@ -299,9 +299,9 @@ void AegiVideoFrame::ConvertFrom(const AegiVideoFrame &source) {
 				y = (*src_y++ - 16) * 298;
 
 				// Assign
-				*dst++ = MID(0,(y + 516 * u           + 128) >> 8,255);	// Blue
-				*dst++ = MID(0,(y - 100 * u - 208 * v + 128) >> 8,255);	// Green
-				*dst++ = MID(0,(y           + 409 * v + 128) >> 8,255);	// Red
+				*dst++ = ClampSignedInteger32((y + 516 * u + 128) >> 8,0,255);				// Blue
+				*dst++ = ClampSignedInteger32((y - 100 * u - 208 * v + 128) >> 8,0,255);	// Green
+				*dst++ = ClampSignedInteger32((y + 409 * v + 128) >> 8,0,255);				// Red
 				*dst++ = 0;
 			}
 		}