Includes: Only From `Source/` (#873)

* Includes: Only From `Source/`

Avoid adding all directories to include paths:

- automatically structure includes more clearly, e.g. a util include
  with a short name is clearly seen as such
- should have some small positive impact on compile time, since the
  compiler has to search less directories for an include file

* Includes: Fix Non-Local Paths

Add missing prefix relative to `Source/` for WarpX-local includes.

2 files changed, 1 insertions, 3 deletions

diff --git a/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/Make.package b/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/Make.package
index 086fc82a0..93cefcb66 100644
--- a/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/Make.package
+++ b/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/Make.package
@@ -3,6 +3,4 @@ CEXE_sources += PsatdAlgorithm.cpp
 CEXE_sources += GalileanAlgorithm.cpp
 CEXE_sources += PMLPsatdAlgorithm.cpp
 
-
-INCLUDE_LOCATIONS += $(WARPX_HOME)/Source/FieldSolver/SpectralSolver/SpectralAlgorithms
 VPATH_LOCATIONS   += $(WARPX_HOME)/Source/FieldSolver/SpectralSolver/SpectralAlgorithms
diff --git a/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/SpectralBaseAlgorithm.cpp b/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/SpectralBaseAlgorithm.cpp
index c917391f9..73a0bb9af 100644
--- a/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/SpectralBaseAlgorithm.cpp
+++ b/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/SpectralBaseAlgorithm.cpp
@@ -4,7 +4,7 @@
  *
  * License: BSD-3-Clause-LBNL
  */
-#include <SpectralBaseAlgorithm.H>
+#include "SpectralBaseAlgorithm.H"
 #include <cmath>
 
 using namespace amrex;