With the transforms on cuFFT the capture's cost was no longer the transforms: on a 16 Mpixel
detector they are 26 ms, while bringing the four convolution surfaces back is 0.9 s, the
masked Pearson over them is 0.4 s and the greedy search is 1.4 s. All three now run where the
surfaces already are, and only the shortlist crosses PCIe.
The engine interface gains one virtual, PointShortlist, whose default is exactly what the
code did before - PointSurfaces, then BeamCenterPointScore, then BeamCenterShortlist2D on the
host - so the CPU path is unchanged and an engine that has nothing to gain overrides nothing.
Those two functions stop being file-local and become the documented reference the device
kernels are held to.
Memory: three 2h x 2w surfaces, not four. The last inverse's output is read where it lies in
the transform buffer, which nothing overwrites afterwards. Peak on a 16 Mpixel detector goes
from 1.68 GB to 2.55 GB, and DeviceMemoryNeeded counts the surfaces so the fit check and the
CPU fallback still cover it.
The parity test is widened to compensate for what the two paths no longer share. It now
compares the four convolutions, the scored surface (the device kernel against
BeamCenterPointScore, which is what PointScoreSurface exists for), the shortlist (the device
search against BeamCenterShortlist2D on one surface, exactly - the device path is
deterministic), and the whole score. Where the surfaces are compared the tolerance is stated
against the shortlist's reach: r is a ratio of two cancellations, so a weak centre carries
1e-4 of the transform's 1e-6 whichever path computed it, and at a peak - the only part of the
surface anything reads - the two agree to 7.5e-6.
leonarski_f
0f11897615