Create a simplified Falcor material system in slang test (#2721)

* Duplicate an example of differentiating Falcor's material system

* Add a second BSDF

* WIP: update test; grad didn't pass through

* Finalize test

---------

Co-authored-by: Lifan Wu <lifanw@nvidia.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/tests/autodiff/material/DiffuseMaterial.slang b/tests/autodiff/material/DiffuseMaterial.slang
new file mode 100644
index 000000000..e762e17c8
--- /dev/null
+++ b/tests/autodiff/material/DiffuseMaterial.slang
@@ -0,0 +1,17 @@
+//TEST_IGNORE_FILE:
+
+__exported import IMaterial;
+__exported import DiffuseMaterialInstance;
+
+struct DiffuseMaterial : IMaterial
+{
+    float3 baseColor;
+
+    typedef DiffuseMaterialInstance MaterialInstance;
+
+    DiffuseMaterialInstance setupMaterialInstance()
+    {
+        DiffuseMaterialInstance mi = { {baseColor} };
+        return mi;
+    }
+};