parse_camera rendering bug

CHANGELOG.md

@@ -46,6 +46,7 @@ and this project aspires to adhere to [Semantic Versioning](https://semver.org/s
 - Updated several preferred tpl versions
 
 ### Fixed
+- Fix parse_camera where order you apply camera operations matters.
 - Fixed WarpX filter that was not allowing for rendering of the output streamlines
 - Fixed Uniform Grid bug only accepting 2D slices along the Z-axis.
 - Resolved a few cases where MPI_COMM_WORLD was used instead instead of the selected MPI communicator.

src/libs/ascent/runtimes/flow_filters/ascent_runtime_conduit_to_vtkm_parsing.cpp

@@ -114,22 +114,41 @@ parse_camera(const conduit::Node camera_node, vtkm::rendering::Camera &camera)
                           view_vals[3]);
   }
 
-  if(camera_node.has_child("look_at"))
+  if(camera_node.has_child("position"))
   {
       conduit::Node n;
-      camera_node["look_at"].to_float64_array(n);
+      camera_node["position"].to_float64_array(n);
       const float64 *coords = n.as_float64_ptr();
-      vtkmVec3f look_at(coords[0], coords[1], coords[2]);
-      camera.SetLookAt(look_at);
+      vtkmVec3f position(coords[0], coords[1], coords[2]);
+      camera.SetPosition(position);
   }
 
-  if(camera_node.has_child("position"))
+  // this is an offset from the current azimuth
+  if(camera_node.has_child("azimuth"))
+  {
+      vtkm::Float64 azimuth = camera_node["azimuth"].to_float64();
+      camera.Azimuth(azimuth);
+  }
+
+  if(camera_node.has_child("elevation"))
+  {
+      vtkm::Float64 elevation = camera_node["elevation"].to_float64();
+      camera.Elevation(elevation);
+  }
+
+  if(camera_node.has_child("zoom"))
+  {
+      double zoom = camera_node["zoom"].to_float64();
+      camera.Zoom(zoom_to_vtkm_zoom(zoom));
+  }
+
+  if(camera_node.has_child("look_at"))
   {
       conduit::Node n;
-      camera_node["position"].to_float64_array(n);
+      camera_node["look_at"].to_float64_array(n);
       const float64 *coords = n.as_float64_ptr();
-      vtkmVec3f position(coords[0], coords[1], coords[2]);
-      camera.SetPosition(position);
+      vtkmVec3f look_at(coords[0], coords[1], coords[2]);
+      camera.SetLookAt(look_at);
   }
 
   if(camera_node.has_child("up"))
@@ -155,12 +174,6 @@ parse_camera(const conduit::Node camera_node, vtkm::rendering::Camera &camera)
       if(camera_node.has_child("ypan")) xpan = camera_node["ypan"].to_float64();
       camera.Pan(xpan, ypan);
   }
-
-  if(camera_node.has_child("zoom"))
-  {
-      double zoom = camera_node["zoom"].to_float64();
-      camera.Zoom(zoom_to_vtkm_zoom(zoom));
-  }
   //
   // With a new potential camera position. We need to reset the
   // clipping plane as not to cut out part of the data set
@@ -179,18 +192,6 @@ parse_camera(const conduit::Node camera_node, vtkm::rendering::Camera &camera)
       clipping_range.Max = camera_node["far_plane"].to_float64();
       camera.SetClippingRange(clipping_range);
   }
-
-  // this is an offset from the current azimuth
-  if(camera_node.has_child("azimuth"))
-  {
-      vtkm::Float64 azimuth = camera_node["azimuth"].to_float64();
-      camera.Azimuth(azimuth);
-  }
-  if(camera_node.has_child("elevation"))
-  {
-      vtkm::Float64 elevation = camera_node["elevation"].to_float64();
-      camera.Elevation(elevation);
-  }
 }
 
 bool is_valid_name(const std::string &name)

src/libs/vtkh/rendering/Renderer.cpp

@@ -6,6 +6,8 @@
 #include <vtkh/utils/vtkm_dataset_info.hpp>
 #include <vtkm/rendering/raytracing/Logger.h>
 
+#define _DEBUG 0
+
 namespace vtkh {
 
 Renderer::Renderer()
@@ -212,7 +214,16 @@ Renderer::DoExecute()
   }
 
   int total_renders = static_cast<int>(m_renders.size());
-
+
+#if _DEBUG
+  std::cerr << "total renders: " << total_renders << std::endl;
+  vtkm::Bounds g_bounds = m_input->GetGlobalBounds();
+  std::cerr << "Global Bounds: " << std::endl;
+  std::cerr << "X: " << g_bounds.X.Min << " " << g_bounds.X.Max << std::endl;
+  std::cerr << "Y: " << g_bounds.Y.Min << " " << g_bounds.Y.Max << std::endl;
+  std::cerr << "Z: " << g_bounds.Z.Min << " " << g_bounds.Z.Max << std::endl;
+#endif
+
   int num_domains = static_cast<int>(m_input->GetNumberOfDomains());
   for(int dom = 0; dom < num_domains; ++dom)
   {
@@ -228,6 +239,7 @@ Renderer::DoExecute()
     const vtkm::cont::Field &field = data_set.GetField(m_field_name);
     const vtkm::cont::CoordinateSystem &coords = data_set.GetCoordinateSystem();
 
+
     if(cellset.GetNumberOfCells() == 0)
     {
       continue;
@@ -248,6 +260,10 @@ Renderer::DoExecute()
 
       Render::vtkmCanvas &canvas = m_renders[i].GetCanvas();
       const vtkmCamera &camera = m_renders[i].GetCamera();
+#if _DEBUG     
+      std::cerr << "CAMERA BEFORE VTKM RENDERCELLS: " << std::endl;
+      camera.Print();
+#endif
       m_mapper->SetCanvas(&canvas);
       m_mapper->RenderCells(cellset,
                             coords,