diff --git a/.github/workflows/ci-gpu.yml b/.github/workflows/ci-gpu.yml
index f11a982d5..e38f7c60e 100644
--- a/.github/workflows/ci-gpu.yml
+++ b/.github/workflows/ci-gpu.yml
@@ -81,7 +81,7 @@ jobs:
     - name: Configure
       run: |
         cd build
-        cmake .. -DPBRT_USE_PREGENERATED_RGB_TO_SPECTRUM_TABLES=True -DPBRT_OPTIX7_PATH=../optix/${{ matrix.optix }} -DPBRT_GPU_SHADER_MODEL=sm_80
+        cmake .. -DCMAKE_TOOLCHAIN_FILE="$env:VCPKG_INSTALLATION_ROOT"/scripts/buildsystems/vcpkg.cmake -DPBRT_USE_PREGENERATED_RGB_TO_SPECTRUM_TABLES=True -DPBRT_OPTIX7_PATH=../optix/${{ matrix.optix }} -DPBRT_GPU_SHADER_MODEL=sm_80
 
     - name: Build
       # We need to limit the number of jobs so that it doesn't OOM 
diff --git a/src/pbrt/textures.cpp b/src/pbrt/textures.cpp
index 5ee23c805..48a0aeb2b 100644
--- a/src/pbrt/textures.cpp
+++ b/src/pbrt/textures.cpp
@@ -23,6 +23,11 @@
 
 #include <Ptexture.h>
 
+// Windows strikes again.
+#ifdef RGB
+#undef RGB
+#endif
+
 namespace pbrt {
 
 std::string TextureEvalContext::ToString() const {