Terrace node, make smoothness a hybrid input

Author: Auburn

include/FastNoise/Generators/Modifiers.h

@@ -282,14 +282,16 @@ namespace FastNoise
 
         void SetSource( SmartNodeArg<> gen ) { this->SetSourceMemberVariable( mSource, gen ); }
         void SetStepCount( float stepCount ) { mStepCount = stepCount; mStepCountRecip = 1 / stepCount; }
-        void SetSmoothness( float smoothness ) { mSmoothness = smoothness; if( mSmoothness != 0.0f ) mSmoothnessRecip = 1 + 1 / smoothness; }
+        
+        void SetSmoothness( float smoothness ) { mSmoothness = smoothness; if( smoothness != 0.0f ) mSmoothnessRecip = 1 + 1 / smoothness; }
+        void SetSmoothness( SmartNodeArg<> gen ) { this->SetSourceMemberVariable( mSmoothness, gen ); }
 
     protected:
         GeneratorSource mSource;
+        HybridSource mSmoothness = 0.0f;
+        float mSmoothnessRecip = 0.0f;
         float mStepCount = 1.0f;
         float mStepCountRecip = 1.0f;
-        float mSmoothness = 0.0f;
-        float mSmoothnessRecip = 0.0f;
     };
 
 #ifdef FASTNOISE_METADATA
@@ -303,7 +305,7 @@ namespace FastNoise
             groups.push_back( "Modifiers" );
             this->AddGeneratorSource( "Source", &Terrace::SetSource );
             this->AddVariable( { "Step Count", "Increasing the step count reduces the size of each step" }, 1.0f, &Terrace::SetStepCount );
-            this->AddVariable( { "Smoothness", "How smooth the transitions between steps are" }, 0.0f, &Terrace::SetSmoothness );
+            this->AddHybridSource( { "Smoothness", "How smooth the transitions between steps are" }, 0.0f, &Terrace::SetSmoothness, &Terrace::SetSmoothness );
 
             description =
                 "Cuts the input value into steps to give a terraced terrain effect";

include/FastNoise/Generators/Modifiers.inl

@@ -131,8 +131,31 @@ class FastSIMD::DispatchClass<FastNoise::Terrace, SIMD> final : public virtual F
         source *= float32v( mStepCount );
         float32v rounded = FS::Round( source );
 
-        if( mSmoothness != 0.0f )
+        if( mSmoothness.simdGeneratorPtr )
         {
+            // Dynamic smoothness from generator
+            float32v smoothness = this->GetSourceValue( mSmoothness, seed, pos... );
+            mask32v smoothnessMask = smoothness != float32v( 0.0f );
+
+            if( FS::AnyMask( smoothnessMask ) )
+            {
+                float32v diff = rounded - source;
+                mask32v diffSign = diff < float32v( 0 );
+
+                diff = FS::Abs( diff );
+                diff = float32v( 0.5f ) - diff;
+
+                float32v smoothnessRecip = float32v( 1.0f ) + FS::Reciprocal( smoothness );
+                diff *= smoothnessRecip;
+                diff = FS::Min( diff, float32v( 0.5f ) );
+                diff = FS::Select( diffSign, float32v( 0.5f ) - diff, diff - float32v( 0.5f ) );
+
+                rounded = FS::Select( smoothnessMask, rounded + diff, rounded );
+            }
+        }
+        else if( mSmoothness.constant != 0.0f )
+        {
+            // Constant smoothness, use precomputed reciprocal
             float32v diff = rounded - source;
             mask32v diffSign = diff < float32v( 0 );