Fix handling of RT accelerations structures for non-RT stages (#1753)

* Fix handling of RT accelerations structures for non-RT stages

The recent change that added support for the `GL_EXT_ray_query` extension made is so that a shader that declares a `RaytracingAccelerationStructure` as an input to a non-RT shader stage but then never *uses* it wouldn't enable any RT extension, resulting in a compilation failure in glslang.

This change reverts that behavior so that such shaders enable `GL_EXT_ray_tracing`, since that is the older of the two RT extensions that introduce `accelerationStructureEXT`. It is possible that we will need to revisit this decision based on which of the two extensions ends up being more broadly supported, but I think that right now it is fair to say that there exist drivers that support `GL_EXT_ray_tracing` but not `GL_EXT_ray_query`, so the former is the better default.

* fixup: failing test

1 files changed, 6 insertions, 10 deletions

diff --git a/source/slang/slang-emit-glsl.cpp b/source/slang/slang-emit-glsl.cpp
index fb4417119..86339e94b 100644
--- a/source/slang/slang-emit-glsl.cpp
+++ b/source/slang/slang-emit-glsl.cpp
@@ -1831,17 +1831,13 @@ void GLSLSourceEmitter::emitSimpleTypeImpl(IRType* type)
                     // could provide the `accelerationSturctureEXT` type, but there
                     // can be drivers that provide only one and not the other.
                     //
-                    // Because we can't pick one upon just seeing the type, we need to
-                    // emit the type here but *not* call `_requireRayTracing()` or
-                    // anything like it, because we don't yet know the specific extension
-                    // we should ask for.
+                    // For now we will just kludge this by assuming that any driver
+                    // that supports one of these extensions supports the other.
                     //
-                    // TODO: We might eventually want to have this step set a flag that
-                    // will cause a compilation error if nothing else in the code requires
-                    // a specific concrete ray-tracing extension. Ideally all of these
-                    // details could be subusmed under the capability system sooner or
-                    // later.
-                    // 
+                    // TODO: Revisit that decision once the driver landscape is more stable/clear.
+                    //
+                    _requireRayTracing();
+
                     m_writer->emit("accelerationStructureEXT");
                 }
                 break;