build: lcms: upstream in favor of fork; add fast float scaffold

.gitmodules

@@ -64,5 +64,5 @@
 	shallow = true
 [submodule "dependencies/Little-CMS"]
 	path = dependencies/Little-CMS
-	url = https://github.com/Tom94/Little-CMS
+	url = https://github.com/mm2/Little-CMS
 	shallow = true

CMakeLists.txt

@@ -236,7 +236,7 @@ include_directories(
     "${CMAKE_CURRENT_SOURCE_DIR}/include"
 )
 if (TEV_USE_LIBHEIF)
-    include_directories(${LCMS_INCLUDE} ${LIBHEIF_INCLUDE})
+    include_directories(${LIBHEIF_INCLUDE})
 endif()
 
 set(TEV_DEFINITIONS -DTEV_VERSION="${TEV_VERSION_ARCH}")

dependencies/CMakeLists.txt

@@ -104,12 +104,26 @@ if (TEV_USE_LIBHEIF)
     set(LIBHEIF_INCLUDE "${CMAKE_CURRENT_SOURCE_DIR}/libheif/libheif/api" "${CMAKE_CURRENT_BINARY_DIR}/libheif" PARENT_SCOPE)
 
     # Compile Little-CMS for ICC color profile handling
-    set(BUILD_SHARED_LIBS OFF CACHE BOOL " " FORCE)
-    set(BUILD_TOOLS OFF CACHE BOOL " " FORCE)
-    set(BUILD_TESTS OFF CACHE BOOL " " FORCE)
-    add_subdirectory(Little-CMS EXCLUDE_FROM_ALL)
 
-    set(LCMS_INCLUDE "${CMAKE_CURRENT_SOURCE_DIR}/Little-CMS/include" PARENT_SCOPE)
+    # WARNING: Enabling the fast float plugin (GPLv3) causes a License conflict with the rest of tev (BSD 3-clause). Therefore, we disable
+    # it here for now. Currently seeking to purchase a more permissive license as per https://www.littlecms.com/plugin/. Will enable once
+    # this is resolved.
+    file(GLOB LCMS_SRCS
+        Little-CMS/src/*.c Little-CMS/include/*.h
+        # Little-CMS/plugins/fast_float/src/*.c Little-CMS/plugins/fast_float/include/*.h
+    )
+
+    file(GLOB LCMS_HDRS
+        Little-CMS/include/*.h
+        # Little-CMS/plugins/fast_float/include/*.h
+    )
+
+    add_library(lcms2 STATIC ${LCMS_SRCS} ${LCMS_HDRS})
+    set_target_properties(lcms2 PROPERTIES PUBLIC_HEADER "${LCMS_HDRS}")
+    target_include_directories(lcms2 PUBLIC
+        "${CMAKE_CURRENT_SOURCE_DIR}/Little-CMS/include"
+        # "${CMAKE_CURRENT_SOURCE_DIR}/Little-CMS/plugins/fast_float/include"
+    )
 endif()
 
 # Compile OpenEXR

include/tev/imageio/HeifImageLoader.h

@@ -12,6 +12,8 @@ namespace tev {
 
 class HeifImageLoader : public ImageLoader {
 public:
+    HeifImageLoader();
+
     bool canLoadFile(std::istream& iStream) const override;
     Task<std::vector<ImageData>>
         load(std::istream& iStream, const fs::path& path, const std::string& channelSelector, int priority) const override;

src/imageio/HeifImageLoader.cpp

@@ -7,6 +7,7 @@
 #include <libheif/heif.h>
 
 #include <lcms2.h>
+// #include <lcms2_fast_float.h>
 
 #include <ImfChromaticities.h>
 
@@ -15,6 +16,14 @@ using namespace std;
 
 namespace tev {
 
+HeifImageLoader::HeifImageLoader() {
+    cmsSetLogErrorHandler([](cmsContext, cmsUInt32Number errorCode, const char* message) {
+        tlog::error() << fmt::format("lcms error #{}: {}", errorCode, message);
+    });
+
+    // cmsPlugin(cmsFastFloatExtensions());
+}
+
 bool HeifImageLoader::canLoadFile(istream& iStream) const {
     // libheif's spec says it needs the first 12 bytes to determine whether the image can be read.
     uint8_t header[12];
@@ -135,10 +144,6 @@ Task<vector<ImageData>> HeifImageLoader::load(istream& iStream, const fs::path&,
             return (cmsHTRANSFORM) nullptr;
         }
 
-        cmsSetLogErrorHandler([](cmsContext, cmsUInt32Number errorCode, const char* message) {
-            tlog::error() << fmt::format("lcms error #{}: {}", errorCode, message);
-        });
-
         // Create ICC profile from the raw data
         cmsHPROFILE srcProfile = cmsOpenProfileFromMem(profileData.data(), (cmsUInt32Number)profileSize);
         if (!srcProfile) {