Merge branch 'dev/jerrans/REMIX-4388' into 'main'

REMIX-4388: If we find an unsuitable BLAS for updating then we need to force a rebuild

Closes REMIX-4388

See merge request lightspeedrtx/dxvk-remix-nv!1574

Author: jerrans

src/dxvk/rtx_render/rtx_accel_manager.cpp

@@ -603,7 +603,15 @@ namespace dxvk {
       // Try to reuse our dynamic BLAS if it exists
       Rc<PooledBlas>& selectedBlas = blasEntry->dynamicBlas;
 
-      const bool build = forceRebuild || !selectedBlas.ptr() || selectedBlas->accelStructure->info().size != sizeInfo.accelerationStructureSize;
+      bool build = forceRebuild || !selectedBlas.ptr() || selectedBlas->accelStructure->info().size != sizeInfo.accelerationStructureSize;
+
+      // Validate that the selected blas is compatible with the current build info for update purposes
+      bool update = blasEntry->frameLastUpdated == currentFrame;
+      if (update && !build && !validateUpdateMode(selectedBlas->buildInfo, buildInfo)) {
+        // If an update is requested but the BLAS is not compatible with the current build info then force a rebuild
+        update = false;
+        build = true;
+      }
 
       // There is no such BLAS - create one
       if (build) {
@@ -619,12 +627,6 @@ namespace dxvk {
       selectedBlas->frameLastTouched = currentFrame;
       blasEntry->dynamicBlas->opacityMicromapSourceHash = boundOpacityMicromapHash;
 
-      // Validate that the selected blas is compatible with the current build info for update purposes
-      bool update = blasEntry->frameLastUpdated == currentFrame;
-      if (update && !build && !validateUpdateMode(selectedBlas->buildInfo, buildInfo)) {
-        update = false;
-      }
-
       if (update || build) {
         if (update && !build) {
           buildInfo.srcAccelerationStructure = selectedBlas->accelStructure->getAccelStructure();