diff --git a/src/gui/MainWindow.cpp b/src/gui/MainWindow.cpp
index 351611d..ded2d7d 100644
--- a/src/gui/MainWindow.cpp
+++ b/src/gui/MainWindow.cpp
@@ -1,14 +1,71 @@
 #include "MainWindow.h"
 
+#include "hurricanedata/datareader.h"
 #include "cuda_runtime.h"
 #include <csignal>
 #include <iostream>
 #include <memory>
 
+#include <vector>
+#include "consts.h"
 #include "Shader.h"
 #include "input/Widget.h"
 #include "cuda_error.h"
 
+// FIXME: this is the worst code in this project - very ad hoc
+// this is a blocking operation, and really does not follow any practices of code design
+// should really be a proper class like GpuBufferHandler.
+void loadData(float* d_data, const int idx) {
+  std::cout << "hi\n";
+
+  std::vector<float> h_data;
+  std::cout << "hi\n";
+  std::string path = "data/trimmed";
+  std::cout << "hi\n";
+  std::string variable = "T";
+  std::cout << "hi\n";
+
+  DataReader dataReader(path, variable);
+  std::cout << "hi\n";
+
+  size_t dataLength = dataReader.fileLength(idx);
+  std::cout << "hi\n";
+
+  h_data.resize(dataLength);
+  std::cout << "hi\n";
+
+  dataReader.loadFile(h_data.data(), idx);
+  std::cout << "hi\n";
+
+  // getTemperature(h_data, idx); 
+  // getSpeed(h_data, idx); 
+
+  float* hostVolume = new float[VOLUME_WIDTH * VOLUME_HEIGHT * VOLUME_DEPTH];
+  for (int i = 0; i < VOLUME_WIDTH * VOLUME_HEIGHT * VOLUME_DEPTH; i++) {
+    hostVolume[i] = h_data[i + 0*VOLUME_DEPTH*VOLUME_HEIGHT*VOLUME_WIDTH];
+    // Discard missing values
+    if (h_data[i + 0*VOLUME_DEPTH*VOLUME_HEIGHT*VOLUME_WIDTH] + epsilon >= infty) hostVolume[i] = -infty;
+  }
+  std::cout << "hi\n";
+
+  // Reverse the order of hostVolume - why is it upside down anyway?
+  for (int i = 0; i < VOLUME_WIDTH; i++) {
+    for (int j = 0; j < VOLUME_HEIGHT; j++) {
+      for (int k = 0; k < VOLUME_DEPTH/2; k++) {
+        float temp = hostVolume[i + j*VOLUME_WIDTH + k*VOLUME_WIDTH*VOLUME_HEIGHT];
+        hostVolume[i + j*VOLUME_WIDTH + k*VOLUME_WIDTH*VOLUME_HEIGHT] = hostVolume[i + j*VOLUME_WIDTH + (VOLUME_DEPTH - 1 - k)*VOLUME_WIDTH*VOLUME_HEIGHT];
+        hostVolume[i + j*VOLUME_WIDTH + (VOLUME_DEPTH - 1 - k)*VOLUME_WIDTH*VOLUME_HEIGHT] = temp;
+      }
+    }
+  }
+  std::cout << "hi\n";
+
+  // Allocate + copy data to GPU
+  size_t volumeSize = sizeof(float) * VOLUME_WIDTH * VOLUME_HEIGHT * VOLUME_DEPTH;
+  std::cout << "hi\n";
+  cudaMemcpy(d_data, hostVolume, volumeSize, cudaMemcpyHostToDevice);
+  std::cout << "hi\n";
+}
 
 void Window::saveImage() {
   unsigned char* pixels = new unsigned char[this->w * this->h * 3];
@@ -41,6 +98,8 @@ void framebuffer_size_callback(GLFWwindow* window, int w, int h) {
 }
 
 int Window::init(float* data) {
+  this->data = data;
+
   // init glfw
   glfwInit();
   // requesting context version 1.0 makes glfw try to provide the latest version if possible
@@ -124,6 +183,7 @@ void Window::tick() {
   this->widget->tick(1000.0/diff);
   if (this->widget->dateChanged) {
     // TODO: Load new date file here
+    loadData(this->data, this->widget->date);
     this->widget->dateChanged = false;
   }
   if (this->widget->saveImage) {
diff --git a/src/gui/input/Widget.cpp b/src/gui/input/Widget.cpp
index d72243e..bcc42e2 100644
--- a/src/gui/input/Widget.cpp
+++ b/src/gui/input/Widget.cpp
@@ -107,7 +107,6 @@ void Widget::tick(double fps) {
   ImGui::DragFloat("Alpha accum. limit", &this->alphaAcumLimit, 0.01f, 0.0f, 1.0f, "%.2f");
   ImGui::DragInt("Opacity const. (log [1e-5, 1])", &this->opacityConst, 1, 0, 100, "%d%%", ImGuiSliderFlags_AlwaysClamp);
   ImGui::DragFloat("Levoy Width", &this->levoyWidth, 0.01f, 0.0f, 100.0f, "%.2f");
-  // ImGui::DragFloat("Levoy Focus", &this->levoyFocus, 0.01f, 250.0f, 350.0f, "%.2f");
   ImGui::DragFloat("Levoy Focus", &this->levoyFocus, 0.01f, 0.0f, 1.0f, "%.2f");
   
   // the items[] contains the entries for the combobox. The selected index is stored as an int on this->tfComboSelected
@@ -115,9 +114,7 @@ void Widget::tick(double fps) {
   // whatever value is selected here is available on the gpu as d_tfComboSelected.
   const char* items[] = {"Opacity - gradient", "Opacity - sigmoid", "Opacity - constant", "Opacity - levoy"};
   if (ImGui::BeginCombo("Transfer function", items[this->tfComboSelected])) {
-    // std::cout << "hello???\n";
     for (int n = 0; n < IM_ARRAYSIZE(items); n++) {
-      // std::cout << "letsssssa a asdfa???\n";
       const bool is_selected = (this->tfComboSelected == n);
       if (ImGui::Selectable(items[n], is_selected))
         this->tfComboSelected = n;
diff --git a/src/main.cu b/src/main.cu
index e01eb2d..7bf3789 100644
--- a/src/main.cu
+++ b/src/main.cu
@@ -43,8 +43,8 @@ void getSpeed(std::vector<float>& speedData, int idx = 0) {
 
 int main() {
   std::vector<float> data;
-  // getTemperature(data, 254); // 20121028
-  getSpeed(data, 254); // 20121028
+  getTemperature(data, 254); // 20121028
+  // getSpeed(data, 254); // 20121028
 
   std::cout << "DATA size: " << data.size() << std::endl;