1 files changed, 86 insertions, 0 deletions
diff --git a/sys/qpoe/qpiorpix.gx b/sys/qpoe/qpiorpix.gx
new file mode 100644
index 00000000..e766749c
--- /dev/null
+++ b/sys/qpoe/qpiorpix.gx
@@ -0,0 +1,86 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include <mach.h>
+include <syserr.h>
+include	"../qpio.h"
+
+# QPIO_READPIX -- Sample the event list within the indicated rectangular
+# region, using the given blocking factor, to produce a rectangular array
+# of "pixels", where each pixel is a count of the number of events mapping
+# to that location which pass the event attribute filter and region mask.
+#
+# NOTE -- It is left up to the caller to zero the output buffer before
+# we are called.  (We merely increment the counts of the affected pixels).
+
+int procedure qpio_readpix$t (io, obuf, vs, ve, ndim, xblock, yblock)
+
+pointer	io			#I QPIO descriptor
+PIXEL	obuf[ARB]		#O output pixel buffer
+int	vs[ndim], ve[ndim]	#I vectors defining region to be extracted
+int	ndim			#I should be 2 for QPOE
+real	xblock, yblock		#I blocking factors
+
+double	x, y
+pointer	sp, evl, ev_p
+int	evtype, maxpix, maskval, xoff, yoff, xw, yw, nev, totev, pix, i, j
+errchk	qpio_getevents, qpio_setrange, syserr
+int	qpio_getevents()
+
+begin
+	# Verify arguments.
+	if (xblock <= 0 || xblock > (ve[1] - vs[1] + 1))
+	    call syserr (SYS_QPBLOCKOOR)
+	if (yblock <= 0 || yblock > (ve[2] - vs[2] + 1))
+	    call syserr (SYS_QPBLOCKOOR)
+
+	# Compute the size of the output matrix in integer pixels.  This
+	# truncates the last partially filled pixel in each axis.
+
+	xw = int ((ve[1] - vs[1] + 1) / xblock + (EPSILOND * 1000))
+	yw = int ((ve[2] - vs[2] + 1) / yblock + (EPSILOND * 1000))
+	if (xw <= 0 || yw <= 0)
+	    return (0)
+
+	call smark (sp)
+	call salloc (evl, SZ_EVLIST, TY_POINTER)
+
+	xoff = IO_EVXOFF(io)
+	yoff = IO_EVYOFF(io)
+	maxpix = xw * yw
+	totev = 0
+
+	evtype = IO_EVXTYPE(io)
+	if (IO_EVXTYPE(io) != IO_EVYTYPE(io))
+	    call syserr (SYS_QPINVEVT)
+
+	# Define the region from which we wish to read events.
+	call qpio_setrange (io, vs, ve, ndim)
+
+	# Read the events.
+	while (qpio_getevents (io, Memi[evl], maskval, SZ_EVLIST, nev) > 0) {
+	    switch (evtype) {
+	    $for (silrd)
+	    case TY_PIXEL:
+		# Process a sequence of neighbor events.
+		do i = 1, nev {
+		    ev_p = (Memi[evl+i-1] - 1) * SZ_SHORT / SZ_PIXEL + 1
+
+		    x = Mem$t[ev_p+xoff]  
+		    y = Mem$t[ev_p+yoff]
+
+		    j = int ((y - vs[2]) / yblock + (EPSILOND * 1000))
+		    if (j >= 0 && j < yw) {
+			pix = j * xw + (x - vs[1]) / xblock + 1
+			if (pix > 0 && pix <= maxpix)
+			    obuf[pix] = obuf[pix] + 1
+		    }
+		}
+	    $endfor
+	    }
+
+	    totev = totev + nev
+	}
+
+	call sfree (sp)
+	return (totev)
+end