From b86e27a9c4db3686e0cc323d5e4f87bfc7e75da0 Mon Sep 17 00:00:00 2001
From: AndreaRigoni <andrea.rigoni@pd.infn.it>
Date: Tue, 2 Sep 2025 12:42:46 +0200
Subject: [PATCH] add VTK save early

---
 CMakeLists.txt          |  5 +++++
 src/Math/CMakeLists.txt |  3 ++-
 src/Math/VoxImage.cpp   | 34 ++++++++++++++++++++++++++++++++++
 src/Math/VoxImage.h     |  1 +
 4 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3ca4afc..b2d63ef 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -79,6 +79,11 @@ include(${EIGEN3_USE_FILE})
 find_package(ROOT CONFIG REQUIRED)
 include(${ROOT_USE_FILE})
 
+find_package(VTK REQUIRED)
+include(${VTK_USE_FILE})
+
+
+
 option(CENTOS_SUPPORT "VTK definitions for CentOS" OFF)
 if(CENTOS_SUPPORT)
     find_package(VTK CONFIG REQUIRED)
diff --git a/src/Math/CMakeLists.txt b/src/Math/CMakeLists.txt
index de44c98..be21785 100644
--- a/src/Math/CMakeLists.txt
+++ b/src/Math/CMakeLists.txt
@@ -32,7 +32,8 @@ set(SOURCES VoxRaytracer.cpp
             Structured4DGrid.cpp)
 
 set(LIBRARIES ${Eigen_LIBRARY}
-              ${ROOT_LIBRARIES})
+              ${ROOT_LIBRARIES}
+              ${VTK_LIBRARIES})
 
 set(libname ${PACKAGE_LIBPREFIX}Math)
 set(ULIB_SHARED_LIBRARIES ${ULIB_SHARED_LIBRARIES} ${libname} PARENT_SCOPE)
diff --git a/src/Math/VoxImage.cpp b/src/Math/VoxImage.cpp
index 55c4e36..93a9e34 100644
--- a/src/Math/VoxImage.cpp
+++ b/src/Math/VoxImage.cpp
@@ -30,9 +30,43 @@
 
 #include "VoxImage.h"
 
+#include <vtkSmartPointer.h>
+#include <vtkImageData.h>
+
+#include <vtkXMLImageDataWriter.h>
+
 
 namespace uLib {
 
+void Abstract::VoxImage::SaveToVtkVti (const char *file)
+{
+    Abstract::VoxImage *voxels = this;
+
+    vtkSmartPointer<vtkImageData> image = vtkSmartPointer<vtkImageData>::New();
+    image->SetDimensions(voxels->GetDims()(0), voxels->GetDims()(1), voxels->GetDims()(2));
+    image->SetSpacing(voxels->GetSpacing()(0), voxels->GetSpacing()(1), voxels->GetSpacing()(2));
+    image->SetOrigin(voxels->GetOrigin()(0), voxels->GetOrigin()(1), voxels->GetOrigin()(2));
+    image->AllocateScalars(VTK_FLOAT, 1);
+
+    int nx = voxels->GetDims()(0);
+    int ny = voxels->GetDims()(1);
+    int nz = voxels->GetDims()(2);
+
+    size_t npoints = nx*ny*nz;
+    float *scalar = static_cast<float*>(image->GetScalarPointer());
+
+    for (size_t i = 0; i < npoints; i++) {
+        scalar[i] = static_cast<float>(voxels->GetValue(i));
+    }
+
+    vtkSmartPointer<vtkXMLImageDataWriter> writer = vtkSmartPointer<vtkXMLImageDataWriter>::New();
+    writer->SetFileName(file);
+    writer->SetInputData(image);
+    writer->Write();
+}
+
+
+
 void Abstract::VoxImage::ExportToVtk (const char *file, bool density_type)
 {
     FILE * vtk_file = fopen(file,"wb");
diff --git a/src/Math/VoxImage.h b/src/Math/VoxImage.h
index b82b198..fee3a7e 100644
--- a/src/Math/VoxImage.h
+++ b/src/Math/VoxImage.h
@@ -58,6 +58,7 @@ public:
     void ExportToVtk(const char *file, bool density_type = 0);
     void ExportToVtkXml(const char *file, bool density_type = 0);
     int ImportFromVtk(const char *file);
+    void SaveToVtkVti (const char *file);
 
 protected: