LG1PCloudAmbStncl: Use RangeDescriptor obj instead of StagingBuffer

We directly use an instance of RangeDescriptor to avoid incurring
the memory cost of using a StagingBuffer here. It's unnecessary
since these stencils will always be 32bits large.

include/user/pcloudAmbienceStencil.h

@@ -18,16 +18,6 @@ class PcloudAmbienceStencil
 public:
 	typedef uint32_t PcloudAmbienceStimulusValue;
 
-	/**
-	 * RangeDescriptor describes a contiguous range of body spots for
-	 * point cloud ambience stencils.
-	 */
-	struct RangeDescriptor : public Stencil::RangeDescriptor
-	{
-		uint32_t bodySpot;
-		size_t nContiguousSpots;
-	};
-
 	PcloudAmbienceStencil() = default;
 	virtual ~PcloudAmbienceStencil() = default;
 };

include/user/stencil.h

@@ -2,6 +2,7 @@
 #define _STENCIL_H
 
 #include <cstddef>
+#include <cstdint>
 #include <mentalEntity.h>
 
 namespace smo {
@@ -40,6 +41,8 @@ public:
 	 */
 	struct RangeDescriptor
 	{
+		uint32_t bodySpot;
+		size_t nContiguousSpots;
 	};
 
 	Stencil() = default;

stimBuffApis/livoxGen1/CMakeLists.txt

@@ -15,7 +15,6 @@ if(ENABLE_STIMBUFFAPI_livoxGen1)
 	add_library(livoxGen1 SHARED
 		livoxGen1.cpp
 		pcloudStimulusProducer.cpp
-		lg1PcloudAmbienceStencil.cpp
 		ioUringAssemblyEngine.cpp
 		openClCollatingAndMeshingEngine.cpp
 		openClKernels.cl.S

stimBuffApis/livoxGen1/lg1PcloudAmbienceStencil.cpp

@@ -1,19 +0,0 @@
-#include "lg1PcloudAmbienceStencil.h"
-#include <unistd.h>
-
-namespace smo {
-namespace stim_buff {
-
-// Common IOEngineConstraints for LG1 ambience stencil StagingBuffer
-// (used for both input and output constraints)
-const StagingBuffer::IOEngineConstraints
-LG1PcloudAmbienceStencil::stencilBufferConstraints(
-	// slotStartAlignmentByteVal, slotPadToNBytes.
-	sizeof(void*),
-	sizeof(PcloudAmbienceStencil::RangeDescriptor),
-	// frameStartAlignmentByteVal, framePadToNBytes.
-	static_cast<size_t>(sysconf(_SC_PAGE_SIZE)),
-	static_cast<size_t>(sysconf(_SC_PAGE_SIZE)));
-
-} // namespace stim_buff
-} // namespace smo

stimBuffApis/livoxGen1/lg1PcloudAmbienceStencil.h

@@ -3,37 +3,23 @@
 
 #include "livoxGen1.h"
 #include <user/pcloudAmbienceStencil.h>
-#include <user/stagingBuffer.h>
-#include <unistd.h>
+#include <user/stencil.h>
 
 namespace smo {
 namespace stim_buff {
 
 /**
  * LG1PcloudAmbienceStencil represents Livox Gen1-specific stencils for
- * ambience data. The StagingBuffer is sized to handle the worst-case scenario
- * where every ambience body spot requires its own descriptor
- * (nDgramsPerFrame slots).
+ * ambience data. It holds a single RangeDescriptor with bodySpot=0 and
+ * nContiguousSpots=1.
  */
 class LG1PcloudAmbienceStencil
 :	public PcloudAmbienceStencil
 {
 public:
-	// Common IOEngineConstraints for stencil buffer (used for both input and output)
-	static const StagingBuffer::IOEngineConstraints stencilBufferConstraints;
-
-	/**
-	 * Constructor
-	 * @param nDgramsPerFrame Number of datagrams per frame, used to size the
-	 *        stencil buffer for worst-case scenario (one descriptor per dgram)
-	 */
-	explicit LG1PcloudAmbienceStencil(size_t nDgramsPerFrame)
+	explicit LG1PcloudAmbienceStencil()
 	:	PcloudAmbienceStencil(),
-	stencilBuffer(
-		stencilBufferConstraints,  // Input constraints
-		stencilBufferConstraints,  // Output constraints (same as input)
-		nDgramsPerFrame),
-	nRangeDescriptors(0)
+	rangeDescriptor{0, 1}
 	{}
 
 	~LG1PcloudAmbienceStencil() = default;
@@ -41,36 +27,33 @@ public:
 	// Implement pure virtual functions from Stencil
 	bool hasData() const override
 	{
-		return nRangeDescriptors > 0;
+		return true;
 	}
 
 	size_t getRelevantCount() const override
 	{
-		// TODO: Implement based on range descriptors
-		return 0;
+		return rangeDescriptor.nContiguousSpots;
 	}
 
 	bool isRelevant(size_t offset) const override
 	{
-		// TODO: Implement based on range descriptors
-		(void)offset;
-		return false;
+		return (offset >= rangeDescriptor.bodySpot &&
+			offset < rangeDescriptor.bodySpot + rangeDescriptor.nContiguousSpots);
 	}
 
 	size_t getNRangeDescriptors() const override
 	{
-		return nRangeDescriptors;
+		return 1;
 	}
 
 	bool buildStencilMetadata() override
 	{
-		// TODO: Implement stencil metadata building
+		// Metadata is already built (single fixed descriptor)
 		return true;
 	}
 
 public:
-	StagingBuffer stencilBuffer;
-	size_t nRangeDescriptors;
+	smo::cologex::Stencil::RangeDescriptor rangeDescriptor;
 };
 
 } // namespace stim_buff

stimBuffApis/livoxGen1/pcloudAmbienceStimulusBuffer.h

@@ -81,7 +81,7 @@ public:
 
 		// Construct stencils and add to list (FIFO behavior)
 		for (size_t i = 0; i < nStencils; ++i) {
-			stencils.emplace_back(nDgramsPerFrame_);
+			stencils.emplace_back();
 		}
 	}