| 223 | } |
| 224 | |
| 225 | std::optional<size_t> EffectStage::FetchProcessAndAdvance( |
| 226 | Buffers &data, size_t bound, bool doZeroes, size_t outBufferOffset) |
| 227 | { |
| 228 | std::optional<size_t> oCurBlockSize; |
| 229 | // Generator always supplies zeroes in |
| 230 | doZeroes = doZeroes || !mIsProcessor; |
| 231 | if (!doZeroes) |
| 232 | oCurBlockSize = mUpstream.Acquire(mInBuffers, bound); |
| 233 | else { |
| 234 | if (!mCleared) { |
| 235 | // Need to do this the first time, only, that we begin to give zeroes |
| 236 | // to the processor |
| 237 | mInBuffers.Rewind(); |
| 238 | const auto blockSize = mInBuffers.BlockSize(); |
| 239 | for (size_t ii = 0; ii < mInBuffers.Channels(); ++ii) { |
| 240 | auto p = &mInBuffers.GetWritePosition(ii); |
| 241 | std::fill(p, p + blockSize, 0); |
| 242 | } |
| 243 | mCleared = true; |
| 244 | } |
| 245 | oCurBlockSize = { |
| 246 | mIsProcessor ? bound : limitSampleBufferSize(bound, mDelayRemaining) }; |
| 247 | if (!mIsProcessor) |
| 248 | // Do this (ignoring result) so we can correctly Release() upstream |
| 249 | mUpstream.Acquire(mInBuffers, bound); |
| 250 | } |
| 251 | if (!oCurBlockSize) |
| 252 | return {}; |
| 253 | |
| 254 | const auto curBlockSize = *oCurBlockSize; |
| 255 | if (curBlockSize == 0) |
| 256 | assert(doZeroes || mUpstream.Remaining() == 0); // post of Acquire() |
| 257 | else { |
| 258 | // Called only in Acquire() |
| 259 | // invariant or post of mUpstream.Acquire() satisfies pre of Process() |
| 260 | // because curBlockSize <= bound <= mInBuffers.blockSize() |
| 261 | // == data.BlockSize() |
| 262 | // and mInBuffers.BlockSize() <= mInBuffers.Remaining() by invariant |
| 263 | // and data.BlockSize() <= data.Remaining() by pre of Acquire() |
| 264 | for (size_t ii = 0, nn = mInstances.size(); ii < nn; ++ii) { |
| 265 | auto &pInstance = mInstances[ii]; |
| 266 | if (!pInstance) |
| 267 | continue; |
| 268 | if (!Process(*pInstance, ii, data, curBlockSize, outBufferOffset)) |
| 269 | return {}; |
| 270 | } |
| 271 | |
| 272 | if (doZeroes) { |
| 273 | // Either a generator or doing the tail; will count down delay |
| 274 | mLastZeroes = limitSampleBufferSize(curBlockSize, DelayRemaining()); |
| 275 | if (!mIsProcessor) { |
| 276 | // This allows polling the progress meter for a generator |
| 277 | if (!mUpstream.Release()) |
| 278 | return {}; |
| 279 | } |
| 280 | } |
| 281 | else { |
| 282 | // Will count down the upstream |