From 70ab3b53e9e2db2e3bba05f4f133a44af8041eec Mon Sep 17 00:00:00 2001
From: unknown <>
Date: Sun, 10 Mar 2024 17:31:31 -0400
Subject: [PATCH] swap neighbors raw

---
 src/main/c/fluidsim.c               |  2 +-
 src/main/c/includes/mainFunctions.h |  8 ++++
 src/main/c/velocitystep.c           | 57 +++++++++++++++++++++++++++++
 3 files changed, 66 insertions(+), 1 deletion(-)

diff --git a/src/main/c/fluidsim.c b/src/main/c/fluidsim.c
index 298405b..c070db3 100644
--- a/src/main/c/fluidsim.c
+++ b/src/main/c/fluidsim.c
@@ -853,7 +853,7 @@ JNIEXPORT void JNICALL Java_electrosphere_FluidSim_simulate(
             u0 = currentChunk->ju0;
             v0 = currentChunk->jv0;
             w0 = currentChunk->jw0;
-            Java_electrosphere_FluidSim_setBoundsToNeighbors(env,chunkJRaw,DIM,chunkMask,0,jd);
+            setBoundsToNeighborsRaw(env,chunkJRaw,DIM,chunkMask,0,currentChunk->d);
         }
     }
 }
\ No newline at end of file
diff --git a/src/main/c/includes/mainFunctions.h b/src/main/c/includes/mainFunctions.h
index 109dad6..740f66d 100644
--- a/src/main/c/includes/mainFunctions.h
+++ b/src/main/c/includes/mainFunctions.h
@@ -91,6 +91,14 @@ JNIEXPORT void JNICALL Java_electrosphere_FluidSim_advectDensity
 JNIEXPORT void JNICALL Java_electrosphere_FluidSim_setBoundsToNeighbors
   (JNIEnv *, jobject, jint, jint, jint, jobjectArray);
 
+JNIEXPORT void JNICALL setBoundsToNeighborsRaw
+  (JNIEnv * env,
+  jobject this,
+  jint N,
+  jint chunk_mask,
+  jint vector_dir,
+  float ** neighborArray);
+
 /*
  * Class:     electrosphere_FluidSim
  * Method:    copyNeighbors
diff --git a/src/main/c/velocitystep.c b/src/main/c/velocitystep.c
index e731d2b..569f9b6 100644
--- a/src/main/c/velocitystep.c
+++ b/src/main/c/velocitystep.c
@@ -668,6 +668,63 @@ void advect(JNIEnv * env, uint32_t chunk_mask, int N, int b, jobjectArray jrd, j
     }
 }
 
+JNIEXPORT void JNICALL setBoundsToNeighborsRaw
+  (JNIEnv * env,
+  jobject this,
+  jint N,
+  jint chunk_mask,
+  jint vector_dir,
+  float ** neighborArray){
+    int DIM = N;
+    float * target = GET_ARR_RAW(env,neighborArray,CENTER_LOC);
+    float * source;
+    for(int x=1; x < DIM-1; x++){
+        for(int y = 1; y < DIM-1; y++){
+            target[IX(0,x,y)] = vector_dir==BOUND_DIR_U ? -target[IX(1,x,y)] : target[IX(1,x,y)];
+        }
+    }
+    for(int x=1; x < DIM-1; x++){
+        for(int y = 1; y < DIM-1; y++){
+            target[IX(DIM-1,x,y)] =     vector_dir==BOUND_DIR_U ? -target[IX(DIM-2,x,y)] : target[IX(DIM-2,x,y)];
+        }
+    }
+    for(int x=1; x < DIM-1; x++){
+        for(int y = 1; y < DIM-1; y++){
+            //((x)+(DIM)*(y) + (DIM)*(DIM)*(z))
+            target[IX(x,0,y)] =         vector_dir==BOUND_DIR_V ? -target[IX(x,1,y)] : target[IX(x,1,y)];
+            target[IX(x,DIM-1,y)] =     vector_dir==BOUND_DIR_V ? -target[IX(x,DIM-2,y)] : target[IX(x,DIM-2,y)];
+            target[IX(x,y,0)] =         vector_dir==BOUND_DIR_W ? -target[IX(x,y,1)] : target[IX(x,y,1)];
+            target[IX(x,y,DIM-1)] =     vector_dir==BOUND_DIR_W ? -target[IX(x,y,DIM-2)] : target[IX(x,y,DIM-2)];
+        }
+    }
+    for(int x = 1; x < DIM-1; x++){
+        target[IX(x,0,0)]         = (float)(0.5f * (target[IX(x,1,0)] + target[IX(x,0,1)]));
+        target[IX(x,DIM-1,0)]     = (float)(0.5f * (target[IX(x,DIM-2,0)] + target[IX(x,DIM-1,1)]));
+        target[IX(x,0,DIM-1)]     = (float)(0.5f * (target[IX(x,1,DIM-1)] + target[IX(x,0,DIM-2)]));
+        target[IX(x,DIM-1,DIM-1)] = (float)(0.5f * (target[IX(x,DIM-2,DIM-1)] + target[IX(x,DIM-1,DIM-2)]));
+
+        target[IX(0,x,0)] = (float)(0.5f * (target[IX(1,x,0)] + target[IX(0,x,1)]));
+        target[IX(DIM-1,x,0)] = (float)(0.5f * (target[IX(DIM-2,x,0)] + target[IX(DIM-1,x,1)]));
+        target[IX(0,x,DIM-1)] = (float)(0.5f * (target[IX(1,x,DIM-1)] + target[IX(0,x,DIM-2)]));
+        target[IX(DIM-1,x,DIM-1)] = (float)(0.5f * (target[IX(DIM-2,x,DIM-1)] + target[IX(DIM-1,x,DIM-2)]));
+
+
+        target[IX(0,0,x)] = (float)(0.5f * (target[IX(1,0,x)] + target[IX(0,1,x)]));
+        target[IX(DIM-1,0,x)] = (float)(0.5f * (target[IX(DIM-2,0,x)] + target[IX(DIM-1,1,x)]));
+        target[IX(0,DIM-1,x)] = (float)(0.5f * (target[IX(1,DIM-1,x)] + target[IX(0,DIM-2,x)]));
+        target[IX(DIM-1,DIM-1,x)] = (float)(0.5f * (target[IX(DIM-2,DIM-1,x)] + target[IX(DIM-1,DIM-2,x)]));
+
+    }
+    target[IX(0,0,0)]             = (float)((target[IX(1,0,0)]+target[IX(0,1,0)]+target[IX(0,0,1)])/3.0);
+    target[IX(DIM-1,0,0)]         = (float)((target[IX(DIM-2,0,0)]+target[IX(DIM-1,1,0)]+target[IX(DIM-1,0,1)])/3.0);
+    target[IX(0,DIM-1,0)]         = (float)((target[IX(1,DIM-1,0)]+target[IX(0,DIM-2,0)]+target[IX(0,DIM-1,1)])/3.0);
+    target[IX(0,0,DIM-1)]         = (float)((target[IX(0,0,DIM-2)]+target[IX(1,0,DIM-1)]+target[IX(0,1,DIM-1)])/3.0);
+    target[IX(DIM-1,DIM-1,0)]     = (float)((target[IX(DIM-2,DIM-1,0)]+target[IX(DIM-1,DIM-2,0)]+target[IX(DIM-1,DIM-1,1)])/3.0);
+    target[IX(0,DIM-1,DIM-1)]     = (float)((target[IX(1,DIM-1,DIM-1)]+target[IX(0,DIM-2,DIM-1)]+target[IX(0,DIM-1,DIM-2)])/3.0);
+    target[IX(DIM-1,0,DIM-1)]     = (float)((target[IX(DIM-1,0,DIM-2)]+target[IX(DIM-2,0,DIM-1)]+target[IX(DIM-1,1,DIM-1)])/3.0);
+    target[IX(DIM-1,DIM-1,DIM-1)] = (float)((target[IX(DIM-1,DIM-1,DIM-2)]+target[IX(DIM-1,DIM-2,DIM-1)]+target[IX(DIM-1,DIM-1,DIM-2)])/3.0);
+}
+
 JNIEXPORT void JNICALL Java_electrosphere_FluidSim_setBoundsToNeighbors
   (JNIEnv * env,
   jobject this,