Change some indices for better readability

Use level instead of dridNumber in NodeIndicesMultiGPU
and instead of i in loops in MultipleGridBuilder

src/gpu/GridGenerator/grid/GridBuilder/MultipleGridBuilder.cpp

@@ -609,8 +609,8 @@ void MultipleGridBuilder::findGeoFluidNodes()
 const std::vector<uint> *MultipleGridBuilder::getGeoFluidSizes() const
 {
     std::vector<uint> geoFluidSizes;
-    for (uint i = 0; i < grids.size(); i++) {
-        geoFluidSizes.push_back(grids[i]->getGeoFluidSize());
+    for (uint level = 0; level < grids.size(); level++) {
+        geoFluidSizes.push_back(grids[level]->getGeoFluidSize());
     }
     return &geoFluidSizes;
 }
@@ -618,8 +618,8 @@ const std::vector<uint> *MultipleGridBuilder::getGeoFluidSizes() const
 const std::vector<const uint*> *MultipleGridBuilder::getGeoFluidNodeIndices() const
 {
     std::vector<const uint*> getGeoFluidNodes;
-    for (uint i = 0; i < grids.size(); i++) {
-        getGeoFluidNodes.push_back(grids[i]->getGeoFluidNodes());
+    for (uint level = 0; level < grids.size(); level++) {
+        getGeoFluidNodes.push_back(grids[level]->getGeoFluidNodes());
     }
     return &getGeoFluidNodes;
 }

src/gpu/VirtualFluids_GPU/Parameter/NodeIndicesMultiGPU.cpp

@@ -7,12 +7,12 @@ NodeIndicesMultiGPU::NodeIndicesMultiGPU(const std::vector<uint> *geoFluidSizes,
     this->geoFluidNodeIndices = geoFluidNodesIndices;
 }
 
-uint NodeIndicesMultiGPU::getGeoFluidSize(uint gridNumber) 
+uint NodeIndicesMultiGPU::getGeoFluidSize(uint level) 
 { 
-    return (*this->geoFluidSizes)[gridNumber];
+    return (*this->geoFluidSizes)[level];
 }
 
-const uint* NodeIndicesMultiGPU::getGeoFluidNodeIndices(uint gridNumber)
+const uint* NodeIndicesMultiGPU::getGeoFluidNodeIndices(uint level)
 {
-    return (*this->geoFluidNodeIndices)[gridNumber];
+    return (*this->geoFluidNodeIndices)[level];
 }

src/gpu/VirtualFluids_GPU/Parameter/NodeIndicesMultiGPU.h

@@ -13,8 +13,8 @@ class NodeIndicesMultiGPU
 public:
     NodeIndicesMultiGPU(const std::vector<uint> *geoFluidSizes, const std::vector<const uint*> * geoFluidNodes);
 
-    uint getGeoFluidSize(uint gridNumber);
-    const uint* getGeoFluidNodeIndices(uint gridNumber);
+    uint getGeoFluidSize(uint level);
+    const uint *getGeoFluidNodeIndices(uint level);
 };
 
 #endif
\ No newline at end of file