work with reshade (#15)

* use directxtex for dds textures

* use d3dx sdk for wic texture loading until we figure out how to load volume/cube textures without it

* update d3d9 loading

cmake/dxtk.cmake

@@ -0,0 +1,26 @@
+include_guard()
+include(FetchContent)
+
+FetchContent_Declare(
+    DirectXTex
+    GIT_REPOSITORY https://github.com/microsoft/DirectXTex
+    GIT_TAG jul2022)
+FetchContent_GetProperties(directxtex)
+if (directxtex_POPULATED)
+    return()
+endif()
+
+FetchContent_Populate(directxtex)
+
+add_library(directxtex)
+set(SOURCES
+    "${directxtex_SOURCE_DIR}/DDSTextureLoader/DDSTextureLoader9.h"
+    "${directxtex_SOURCE_DIR}/DDSTextureLoader/DDSTextureLoader9.cpp"
+    "${directxtex_SOURCE_DIR}/WICTextureLoader/WICTextureLoader9.h"
+    "${directxtex_SOURCE_DIR}/WICTextureLoader/WICTextureLoader9.cpp"
+    )
+source_group(TREE ${directxtex_SOURCE_DIR} FILES ${SOURCES})
+target_sources(directxtex PRIVATE ${SOURCES})
+target_include_directories(directxtex PUBLIC "${directxtex_SOURCE_DIR}")
+
+set_target_properties(directxtex PROPERTIES FOLDER "Dependencies/")