first density diffusion test

src/main/c/includes/fluid/sim/grid2/density.h

@@ -32,7 +32,7 @@ void fluid_grid2_addDensity(
 /*
  * A single iteration of the jacobi to solve density diffusion
  */
-void fluid_grid2_solveDiffuseDensity(
+LIBRARY_API void fluid_grid2_solveDiffuseDensity(
   int chunk_mask,
   float ** d,
   float ** d0,

src/main/c/includes/fluid/sim/grid2/solver_consts.h

@@ -1,8 +1,40 @@
 #ifndef FLUID_GRID2_SOLVER_CONSTS_H
 #define FLUID_GRID2_SOLVER_CONSTS_H
 
+
+/**
+ * The number of times to relax most solvers
+ */
 #define FLUID_GRID2_LINEARSOLVERTIMES 20
+
+/**
+ * The number of times to relax the vector diffusion solver
+ */
 #define FLUID_GRID2_VECTOR_DIFFUSE_TIMES 20
+
+/**
+ * Width of a single grid cell
+ */
 #define FLUID_GRID2_H (1)
 
+/**
+ * Timestep to simulate by
+ */
+#define FLUID_GRID2_SIM_STEP 0.01f
+
+/**
+ * Really small value used for something
+ */
+#define FLUID_GRID2_REALLY_SMALL_VALUE 0.00001
+
+/**
+ * Diffusion constant
+ */
+#define FLUID_GRID2_DIFFUSION_CONSTANT 0.00001
+
+/**
+ * Viscosity constant
+ */
+#define FLUID_GRID2_VISCOSITY_CONSTANT 0.00001
+
 #endif

src/main/c/includes/fluid/sim/grid2/utilities.h

@@ -16,7 +16,7 @@ void fluid_grid2_add_source(float * x, float * s, float dt);
 /**
  * Sets the bounds of this cube to those of its neighbor
 */
-void fluid_grid2_setBoundsToNeighborsRaw(
+LIBRARY_API void fluid_grid2_setBoundsToNeighborsRaw(
   int chunk_mask,
   int vector_dir,
   float ** neighborArray

src/main/c/src/fluid/sim/grid2/density.c

@@ -41,7 +41,7 @@ void fluid_grid2_addDensity(
 /*
  * A single iteration of the jacobi to solve density diffusion
  */
-void fluid_grid2_solveDiffuseDensity(
+LIBRARY_API void fluid_grid2_solveDiffuseDensity(
   int chunk_mask,
   float ** d,
   float ** d0,

src/main/c/src/fluid/sim/grid2/fluidsim.c

@@ -19,12 +19,6 @@
 #define SAVE_STEPS 0
 #endif
 
-
-#define FLUID_GRID2_REALLY_SMALL_VALUE 0.00001
-
-#define FLUID_GRID2_DIFFUSION_CONSTANT 0.00001
-#define FLUID_GRID2_VISCOSITY_CONSTANT 0.00001
-
 static inline void fluid_grid2_saveStep(float * values, const char * name);
 static inline void fluid_grid2_applyGravity(Chunk * currentChunk, Environment * environment);
 static inline void fluid_grid2_clearArr(float ** d);

src/main/c/src/fluid/sim/grid2/velocity.c

@@ -652,7 +652,7 @@ void fluid_grid2_advect_velocity(uint32_t chunk_mask, int b, float ** jrd, float
 /**
  * Sets the bounds of this cube to those of its neighbor
 */
-void fluid_grid2_setBoundsToNeighborsRaw(
+LIBRARY_API void fluid_grid2_setBoundsToNeighborsRaw(
   int chunk_mask,
   int vector_dir,
   float ** neighborArray

src/test/c/fluid/sim/grid2/density_diffuse_tests.c

@@ -1,4 +1,36 @@
 
+#include "stb/stb_ds.h"
+
+#include "fluid/queue/boundsolver.h"
+#include "fluid/queue/chunkmask.h"
+#include "fluid/queue/chunk.h"
+#include "fluid/env/environment.h"
+#include "fluid/env/utilities.h"
+#include "fluid/sim/grid2/density.h"
+#include "fluid/sim/grid2/solver_consts.h"
+#include "fluid/sim/grid2/utilities.h"
+#include "../../../util/chunk_test_utils.h"
+#include "../../../util/test.h"
+
+
+int fluid_sim_grid2_density_diffuse_tests_kernelx[27] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0,
+    1, 1, 1, 1, 1, 1, 1, 1, 1,
+    2, 2, 2, 2, 2, 2, 2, 2, 2,
+};
+
+int fluid_sim_grid2_density_diffuse_tests_kernely[27] = {
+    0, 0, 0, 1, 1, 1, 2, 2, 2,
+    0, 0, 0, 1, 1, 1, 2, 2, 2,
+    0, 0, 0, 1, 1, 1, 2, 2, 2,
+};
+
+int fluid_sim_grid2_density_diffuse_tests_kernelz[27] = {
+    0, 1, 2, 0, 1, 2, 0, 1, 2,
+    0, 1, 2, 0, 1, 2, 0, 1, 2,
+    0, 1, 2, 0, 1, 2, 0, 1, 2,
+};
+
 
 
 
@@ -7,17 +39,70 @@
 
 
 
+/**
+ * Testing density diffusion
+ */
+int fluid_sim_grid2_density_diffuse_test1(){
+    int rVal = 0;
+    printf("fluid_sim_grid2_density_diffuse_test1\n");
+    Environment * env = fluid_environment_create();
+    int chunkCount =  27;
+
+    Chunk ** queue = NULL;
+    for(int i = 0; i < chunkCount; i++){
+        arrput(queue,chunk_create(
+            fluid_sim_grid2_density_diffuse_tests_kernelx[i],
+            fluid_sim_grid2_density_diffuse_tests_kernely[i],
+            fluid_sim_grid2_density_diffuse_tests_kernelz[i]
+        ));
+        chunk_fill(queue[i],0);
+    }
+    //link neighbors
+    chunk_link_neighbors(queue);
+    fluid_solve_bounds(1,queue,env);
 
 
 
 
+    Chunk * currentChunk = queue[0];
+    currentChunk->d[CENTER_LOC][IX(2,2,2)] = MAX_FLUID_VALUE;
+
+    float * tmpArr;
+    for(int j = 0; j < 27; j++){
+        tmpArr = currentChunk->d[j];
+        currentChunk->d[j] = currentChunk->d0[j];
+        currentChunk->d0[j] = tmpArr;
+    }
+    //diffuse density
+    for(int l = 0; l < FLUID_GRID2_LINEARSOLVERTIMES; l++){
+            fluid_grid2_solveDiffuseDensity(currentChunk->chunkMask,currentChunk->d,currentChunk->d0,currentChunk->u,currentChunk->v,currentChunk->w,FLUID_GRID2_DIFFUSION_CONSTANT,FLUID_GRID2_VISCOSITY_CONSTANT,FLUID_GRID2_SIM_STEP);
+            fluid_grid2_setBoundsToNeighborsRaw(currentChunk->chunkMask,0,currentChunk->d);
+    }
+    //swap all density arrays
+    //swap vector fields
+    for(int j = 0; j < 27; j++){
+        tmpArr = currentChunk->d[j];
+        currentChunk->d[j] = currentChunk->d0[j];
+        currentChunk->d0[j] = tmpArr;
+    }
+
+    //sum the result
+    float afterSum = chunk_queue_sum(queue);
+
+    rVal += assertEqualsFloat(afterSum,MAX_FLUID_VALUE,"Density diffuse step changed density sum!  %f %f  \n");
+
+    return rVal;
+}
 
 
 
-
-
+/**
+ * Testing density diffusion
+ */
 int fluid_sim_grid2_density_diffuse_tests(int argc, char **argv){
     int rVal = 0;
 
+    rVal += fluid_sim_grid2_density_diffuse_test1();
+
     return rVal;
 }