refactor: Move chunkware to third_party

third_party/chunkware_dsp/SimpleGain.h

@@ -0,0 +1,56 @@
+/*
+ *	Gain Functions (header)
+ *
+ *  File		: SimpleGain.h
+ *	Library		: SimpleSource
+ *  Version		: 1.12
+ *  Class		: 
+ *
+ *	2006, ChunkWare Music Software, OPEN-SOURCE
+ *
+ *	Permission is hereby granted, free of charge, to any person obtaining a
+ *	copy of this software and associated documentation files (the "Software"),
+ *	to deal in the Software without restriction, including without limitation
+ *	the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ *	and/or sell copies of the Software, and to permit persons to whom the
+ *	Software is furnished to do so, subject to the following conditions:
+ *
+ *	The above copyright notice and this permission notice shall be included in
+ *	all copies or substantial portions of the Software.
+ *
+ *	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ *	THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *	FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ *	DEALINGS IN THE SOFTWARE.
+ */
+
+
+#ifndef __SIMPLE_GAIN_H__
+#define __SIMPLE_GAIN_H__
+
+#include "SimpleHeader.h"		// common header
+
+namespace chunkware_simple
+{
+	//-------------------------------------------------------------
+	// gain functions
+	//-------------------------------------------------------------
+
+	// linear -> dB conversion
+	static INLINE double lin2dB( double lin ) {
+		static const double LOG_2_DB = 8.6858896380650365530225783783321;	// 20 / ln( 10 )
+		return log( lin ) * LOG_2_DB;
+	}
+
+	// dB -> linear conversion
+	static INLINE double dB2lin( double dB ) {
+		static const double DB_2_LOG = 0.11512925464970228420089957273422;	// ln( 10 ) / 20
+		return exp( dB * DB_2_LOG );
+	}
+
+}	// end namespace chunkware_simple
+
+#endif	// end __SIMPLE_GAIN_H__