random node

1 files changed, 29 insertions, 5 deletions

diff --git a/rotord/rotor.h b/rotord/rotor.h
index ed566c7..b681e72 100755
--- a/rotord/rotor.h
+++ b/rotord/rotor.h
@@ -603,12 +603,33 @@ namespace Rotor {
 	//http://create.stephan-brumme.com/fnv-hash/
 	const uint32_t Prime = 0x01000193; //   16777619
 	const uint32_t Seed  = 0x811C9DC5; // 2166136261
+	/// hash a byte
+	inline uint32_t fnv1a(unsigned char oneByte, uint32_t hash = Seed)
+	{
+	  return (oneByte ^ hash) * Prime;
+	}
+	/// hash a short (two bytes)
+	inline uint32_t fnv1a(unsigned short twoBytes, uint32_t hash = Seed)
+	{
+	  const unsigned char* ptr = (const unsigned char*) &twoBytes;
+	  hash = fnv1a(*ptr++, hash);
+	  return fnv1a(*ptr  , hash);
+	}
+	/// hash a 32 bit integer (four bytes)
+	inline uint32_t fnv1a(uint32_t fourBytes, uint32_t hash = Seed)
+	{
+	  const unsigned char* ptr = (const unsigned char*) &fourBytes;
+	  hash = fnv1a(*ptr++, hash);
+	  hash = fnv1a(*ptr++, hash);
+	  hash = fnv1a(*ptr++, hash);
+	  return fnv1a(*ptr  , hash);
+	}
 	class Random: public Signal_node {
 		public:
 			Random(){};
 			Random(map<string,string> &settings) {
 				base_settings(settings);
-				seed=ofToFloat(find_setting(settings,"amount"));
+				seed=(float)find_setting(settings,"seed",Seed);
 				for (auto p:parameter_inputs){
 					if (p->parameter=="seed") p->receiver=&seed;
 				}
@@ -616,16 +637,19 @@ namespace Rotor {
 			};
 			Random* clone(map<string,string> &_settings) { return new Random(_settings);};
 			const float output(const Time_spec &time) {
-			    if (inputs.size()) { //there should there be a way to specify number of inputs in the code rather than in xml
+			    if (inputs.size()) {
                     if (inputs[0]->connection) {
-                    	return 0.0f;
-                        //return (((Signal_node*)inputs[0]->connection)->get_output(time))/divide_amount;
+                    	//hash the integer part and add the fractional part back on
+                    	float o=(((Signal_node*)inputs[0]->connection)->get_output(time));
+                    	uint32_t m=(int)o;
+	                    return ((float)fnv1a(m,(uint32_t)(seed+0.5f)))+(o-m);
                     }
 			    }
 				return 0.0f;
 			}
 			float seed;
-			uint32_t key;
+		private:
+			
 	};
 	class Signal_output: public Signal_node {
 		public: