Include all Imath headers with via #include <Imath/...>

Since Imath is an external library that installs its headers under a
Imath subdirectory, the conventional construct is for the #include to
use that subdir.

Note that when building with an internal, auto-fetched Imath library,
the ImathConfig.h header needs special attention since its location in
the source tree is not under the Imath subdir. When this is the
situation, symlink/copy ImathConfig.h into the Imath subdir.

Signed-off-by: Cary Phillips <cary@ilm.com>

Author: cary-ilm

cmake/OpenEXRSetup.cmake

@@ -391,6 +391,36 @@ else()
   endif()
 endif()
 
+# Installed Imath headers use #include <Imath/ImathVec.h> and <Imath/ImathConfig.h>.
+# Build-tree Imath targets expose src/Imath (legacy <ImathVec.h>) and a flat
+# config/ImathConfig.h (<ImathConfig.h>). Mirror the installed layout for any
+# non-imported in-tree Imath (FetchContent, add_subdirectory, etc.).
+if(TARGET Imath AND TARGET ImathConfig)
+  get_target_property(_openexr_imath_imported Imath IMPORTED)
+  get_target_property(_openexr_imathcfg_imported ImathConfig IMPORTED)
+  if(NOT _openexr_imath_imported
+     AND NOT _openexr_imathcfg_imported
+     AND EXISTS "${Imath_SOURCE_DIR}/src/Imath/ImathVec.h")
+    set(_openexr_imath_gen_cfg "${Imath_BINARY_DIR}/config/ImathConfig.h")
+    set(_openexr_imath_cfg_compat "${PROJECT_BINARY_DIR}/OpenEXR_ImathIncludeCompat")
+    if(EXISTS "${_openexr_imath_gen_cfg}")
+      file(MAKE_DIRECTORY "${_openexr_imath_cfg_compat}/Imath")
+      configure_file("${_openexr_imath_gen_cfg}"
+                     "${_openexr_imath_cfg_compat}/Imath/ImathConfig.h" COPYONLY)
+    endif()
+    set(_openexr_imath_inc_patch_key "${Imath_SOURCE_DIR}|${Imath_BINARY_DIR}")
+    if(NOT OPENEXR_IMATH_SUBDIR_INCLUDE_PATCH STREQUAL _openexr_imath_inc_patch_key)
+      target_include_directories(Imath INTERFACE
+        "$<BUILD_INTERFACE:${Imath_SOURCE_DIR}/src>")
+      if(EXISTS "${_openexr_imath_gen_cfg}")
+        target_include_directories(ImathConfig INTERFACE
+          "$<BUILD_INTERFACE:${_openexr_imath_cfg_compat}>")
+      endif()
+      set(OPENEXR_IMATH_SUBDIR_INCLUDE_PATCH "${_openexr_imath_inc_patch_key}" CACHE INTERNAL "")
+    endif()
+  endif()
+endif()
+
 ###########################################
 # Check if we need to emulate vld1q_f32_x2
 ###########################################

src/bin/exrcheck/main.cpp

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: BSD-3-Clause
 // Copyright (c) Contributors to the OpenEXR Project.
 
-#include <ImathConfig.h>
+#include <Imath/ImathConfig.h>
 #include <ImfCheckFile.h>
 #include <ImfMisc.h>
 #include <OpenEXRConfig.h>

src/bin/exrenvmap/EnvmapImage.cpp

@@ -10,7 +10,7 @@
 //-----------------------------------------------------------------------------
 
 #include "EnvmapImage.h"
-#include <ImathFun.h>
+#include <Imath/ImathFun.h>
 
 #include "namespaceAlias.h"
 using namespace IMF;

src/bin/exrenvmap/EnvmapImage.h

@@ -14,7 +14,7 @@
 
 #include "namespaceAlias.h"
 
-#include <ImathBox.h>
+#include <Imath/ImathBox.h>
 #include <ImfArray.h>
 #include <ImfEnvmap.h>
 #include <ImfRgba.h>

src/bin/exrenvmap/namespaceAlias.h

@@ -7,7 +7,7 @@
 #define NAMESPACEALIAS_H_
 
 #include "IexNamespace.h"
-#include "ImathNamespace.h"
+#include <Imath/ImathNamespace.h>
 #include "ImfNamespace.h"
 
 namespace IMF   = OPENEXR_IMF_NAMESPACE;

src/bin/exrmakepreview/makePreview.cpp

@@ -11,8 +11,8 @@
 
 #include "makePreview.h"
 
-#include <ImathFun.h>
-#include <ImathMath.h>
+#include <Imath/ImathFun.h>
+#include <Imath/ImathMath.h>
 #include <ImfArray.h>
 #include <ImfInputFile.h>
 #include <ImfOutputFile.h>

src/bin/exrmaketiled/Image.h

@@ -12,7 +12,7 @@
 //
 //----------------------------------------------------------------------------
 
-#include <ImathBox.h>
+#include <Imath/ImathBox.h>
 #include <ImfArray.h>
 #include <ImfFrameBuffer.h>
 #include <ImfPixelType.h>

src/bin/exrmaketiled/makeTiled.cpp

@@ -13,7 +13,7 @@
 #include "Image.h"
 
 #include "Iex.h"
-#include "ImathFun.h"
+#include <Imath/ImathFun.h>
 #include "ImfChannelList.h"
 #include "ImfDeepScanLineInputPart.h"
 #include "ImfDeepScanLineOutputPart.h"

src/bin/exrmaketiled/namespaceAlias.h

@@ -7,7 +7,7 @@
 #define NAMESPACEALIAS_H_
 
 #include <IexNamespace.h>
-#include <ImathNamespace.h>
+#include <Imath/ImathNamespace.h>
 #include <ImfNamespace.h>
 
 namespace IMF   = OPENEXR_IMF_NAMESPACE;

src/bin/exrmultiview/Image.h

@@ -13,7 +13,7 @@
 //----------------------------------------------------------------------------
 
 #include <Iex.h>
-#include <ImathBox.h>
+#include <Imath/ImathBox.h>
 #include <ImfArray.h>
 #include <ImfChannelList.h>
 #include <ImfFrameBuffer.h>