1 files changed, 62 insertions, 0 deletions
diff --git a/sys/plio/plpoint.x b/sys/plio/plpoint.x
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+++ b/sys/plio/plpoint.x
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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include <plset.h>
+include <plio.h>
+
+# PL_POINT -- Perform a rasterop operation on a single point in a line of a
+# 2-dimensional plane of a mask.  If the dimensionality of the mask exceeds 2,
+# the pl_setplane() procedure should be called first to define the plane of
+# the mask to be modified.
+
+procedure pl_point (pl, x, y, rop)
+
+pointer	pl			#I mask descriptor
+int	x			#I pixel to be modified
+int	y			#I line to be modified
+int	rop			#I rasterop defining operation
+
+long	v[PL_MAXDIM]
+int	npix, ll_len
+pointer	sp, ll_out, ll_reg, rl_out, ll_dst, op
+errchk	plvalid, pl_access, pl_linerop, pl_update
+pointer	pl_access()
+int	pl_r2li()
+
+begin
+	call plvalid (pl)
+	call amovl (PL_PLANE(pl,1), v, PL_MAXDIM)
+	v[2] = y
+
+	call smark (sp)
+	call salloc (ll_out, LL_MAXLEN(pl), TY_SHORT)
+	call salloc (ll_reg, LL_CURHDRLEN + 6, TY_SHORT)
+	call salloc (rl_out, RL_FIRST * 3, TY_INT)
+
+	# Access the destination line in the mask.
+	ll_dst = pl_access (pl, v)
+
+	# Construct the edit-region list.
+	npix = 1
+	RLI_AXLEN(rl_out) = npix
+	RLI_LEN(rl_out) = RL_FIRST
+
+	op = rl_out + (RL_FIRST - 1) * 3
+	Memi[op+RL_XOFF] = 1
+	Memi[op+RL_NOFF] = npix
+	Memi[op+RL_VOFF] = 1
+
+	ll_len = pl_r2li (Memi[rl_out], 1, Mems[ll_reg], npix)
+
+	# Edit the affected line.
+	call pl_linerop (Mems[ll_reg], 1, 1, Mems[ll_dst], x, PL_MAXVAL(pl),
+	    Mems[ll_out], npix, rop)
+
+	# Update the edited line in the mask.
+	call pl_update (pl, v, Mems[ll_out])
+
+	# Compress the mask if excessive free space has accumulated.
+	if (PL_NEEDCOMPRESS(pl))
+	    call pl_compress (pl)
+
+	call sfree (sp)
+end