simplify the Conversion ReserveResult API

Author: devsh

include/nbl/video/utilities/CAssetConverter.h

@@ -965,34 +965,27 @@ class CAssetConverter : public core::IReferenceCounted
 				inline uint64_t getMinASBuildScratchSize(const bool forHostOps) const
 				{
 					assert(m_minASBuildScratchSize[forHostOps]<=m_maxASBuildScratchSize[forHostOps]);
-					assert((forHostOps ? willHostASBuild():willDeviceASBuild()) == (m_maxASBuildScratchSize[forHostOps]>0));
 					return m_minASBuildScratchSize[forHostOps];
 				}
 				// Enough memory to build and compact all the Acceleration Structures at once, obviously respecting order of BLAS (build->compact) -> TLAS (build->compact)
 				inline uint64_t getMaxASBuildScratchSize(const bool forHostOps) const
 				{
 					assert(m_minASBuildScratchSize[forHostOps]<=m_maxASBuildScratchSize[forHostOps]);
-					assert((forHostOps ? willHostASBuild():willDeviceASBuild()) == (m_maxASBuildScratchSize[forHostOps]>0));
 					return m_maxASBuildScratchSize[forHostOps];
 				}
-				// What usage flags your scratch buffer must have, if returns NONE means are no Device AS Builds to perform.
-				inline auto getASBuildScratchUsages() const
-				{
-					assert((m_ASBuildScratchUsages!=IGPUBuffer::E_USAGE_FLAGS::EUF_NONE)==willDeviceASBuild());
-					return m_ASBuildScratchUsages;
-				}
 				// tells you if you need to provide a valid `SConvertParams::scratchForDeviceASBuild`
-				inline bool willDeviceASBuild() const {return m_willDeviceBuildSomeAS;}
+				inline bool willDeviceASBuild() const {return getMinASBuildScratchSize(false)>0;}
 				// tells you if you need to provide a valid `SConvertParams::scratchForHostASBuild`
 				inline bool willHostASBuild() const
 				{
-					assert(m_willHostBuildSomeAS==false); // host builds not supported yet
-					return m_willHostBuildSomeAS;
+					const bool retval = getMinASBuildScratchSize(true)>0;
+					assert(!retval); // host builds not supported yet
+					return retval;
 				}
 				// tells you if you need to provide a valid `SConvertParams::compactedASAllocator`
 				inline bool willCompactAS() const
 				{
-					assert((willDeviceASBuild()||willHostASBuild())==m_willCompactSomeAS);
+					assert(!m_willCompactSomeAS || willDeviceASBuild() || willHostASBuild());
 					return m_willCompactSomeAS;
 				}
 
@@ -1089,11 +1082,7 @@ class CAssetConverter : public core::IReferenceCounted
 				// 0 for device builds, 1 for host builds
 				uint64_t m_minASBuildScratchSize[2] = {0,0};
 				uint64_t m_maxASBuildScratchSize[2] = {0,0};
-				// is there even more than one usage needed?
-				core::bitflag<IGPUBuffer::E_USAGE_FLAGS> m_ASBuildScratchUsages = IGPUBuffer::E_USAGE_FLAGS::EUF_NONE;
-				// TODO: do we need those bools?
-				uint8_t m_willDeviceBuildSomeAS : 1 = false;
-				uint8_t m_willHostBuildSomeAS : 1 = false;
+				// We do all compactions on the Device for simplicity
 				uint8_t m_willCompactSomeAS : 1 = false;
 
 				//

src/nbl/video/utilities/CAssetConverter.cpp

@@ -3462,17 +3462,15 @@ ISemaphore::future_t<IQueue::RESULT> CAssetConverter::convert_impl(SReserveResul
 			}
 		}
 
-#ifdef NBL_ACCELERATION_STRUCTURE_CONVERSION
 		// check things necessary for building Acceleration Structures
-		using buffer_usage_f = IGPUBuffer::E_USAGE_FLAGS;
-		if (reservations.m_ASBuildScratchUsages!=buffer_usage_f::EUF_NONE)
+		if (reservations.willDeviceASBuild())
 		{
 			if (!params.scratchForDeviceASBuild)
 			{
 				logger.log("An Acceleration Structure will be built on Device but no scratch allocator provided!",system::ILogger::ELL_ERROR);
 				return retval;
 			}
-			// TODO: do the build input buffers also need `EUF_STORAGE_BUFFER_BIT` ?
+			using buffer_usage_f = IGPUBuffer::E_USAGE_FLAGS;
 			constexpr buffer_usage_f asBuildInputFlags = buffer_usage_f::EUF_ACCELERATION_STRUCTURE_BUILD_INPUT_READ_ONLY_BIT|buffer_usage_f::EUF_TRANSFER_DST_BIT|buffer_usage_f::EUF_SHADER_DEVICE_ADDRESS_BIT;
 			// we may use the staging buffer directly to skip an extra copy on small enough geometries
 			if (!params.utilities->getDefaultUpStreamingBuffer()->getBuffer()->getCreationParams().usage.hasFlags(asBuildInputFlags))
@@ -3496,7 +3494,7 @@ ISemaphore::future_t<IQueue::RESULT> CAssetConverter::convert_impl(SReserveResul
 			}
 		}
 		// the elusive and exotic host builds
-		if (reservations.m_willHostBuildSomeAS && !params.scratchForHostASBuild)
+		if (reservations.willHostASBuild() && !params.scratchForHostASBuild)
 		{
 			logger.log("An Acceleration Structure will be built on the Host but no Scratch Memory Allocator provided!", system::ILogger::ELL_ERROR);
 			return retval;
@@ -3507,7 +3505,6 @@ ISemaphore::future_t<IQueue::RESULT> CAssetConverter::convert_impl(SReserveResul
 			logger.log("An Acceleration Structure will be compacted but no Device Memory Allocator provided!", system::ILogger::ELL_ERROR);
 			return retval;
 		}
-#endif
 
 		//
 		auto findInStaging = [&reservations]<Asset AssetType>(const typename asset_traits<AssetType>::video_t* gpuObj)->core::blake3_hash_t*