Limited angle CBCT reconstruction issue

I tried to follow the closed issue #40 for limited angle CBCT reconstruction. In #40, fan-beam geometry was used and I use conebeam geometry:

numRows = 768
numCols = 1024
numAngles = 360
angles=360.0
pixelSize = 0.388
device_1=th.device("cuda:0")
leapct.set_conebeam(numAngles, numRows, numCols, pixelSize, pixelSize, 0.5*(numRows-1), 0.5*(numCols-1)-412, leapct.setAngleArray(numAngles, angles), 1000, 1500)
leapct.set_offsetScan(True)
leapct.set_volume(256, 256, 87, voxelWidth=2*0.908, voxelHeight=2.0)
leapct.print_parameters()
g = leapct.allocateProjections()
f = leapct.allocateVolume()
f = leapct.load_volume('..\pro_001_cbct_crop_fit.npy').astype(np.float32)
f = f/30
f = np.ascontiguousarray(f)
leapct.project(g,f)

If numAngles and angles are 360, the projections are correct:

but if numAngles and angles are other than 360, the projections are very strange and incorrect:

Could you let me know if there are some setting incorrect and how can I fix this issue?

Thank you very much.

Ryan

Start by reproducing the supplied cone-beam setup and reading the entry points set_conebeam, setAngleArray, set_offsetScan, and project. Compare the generated projections when numAngles and angles are 360 versus other values; done means non-360-angle projections are geometrically correct or the issue is narrowed to an incorrect setting.