1 files changed, 34 insertions, 0 deletions
diff --git a/sys/imio/impl1.gx b/sys/imio/impl1.gx
new file mode 100644
index 00000000..4fe23b4b
--- /dev/null
+++ b/sys/imio/impl1.gx
@@ -0,0 +1,34 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<imhdr.h>
+include	<imio.h>
+
+# IMPL1? -- Put a line to an apparently one dimensional image.  If there
+# is only one input buffer, no image section, we are not referencing out of
+# bounds, and no datatype conversion needs to be performed, directly access
+# the pixels to reduce the overhead per line.
+
+pointer procedure impl1$t (im)
+
+pointer	im			# image header pointer
+int	fd, nchars
+long	offset
+pointer	bp, impgs$t(), fwritep()
+errchk	imopsf
+
+begin
+	repeat {
+	    if (IM_FAST(im) == YES && IM_PIXTYPE(im) == TY_PIXEL) {
+		fd = IM_PFD(im)
+		if (fd == NULL) {
+		    call imopsf (im)
+		    next
+		}
+		offset = IM_PIXOFF(im)
+		nchars = IM_PHYSLEN(im,1) * SZ_PIXEL
+		ifnoerr (bp = (fwritep (fd, offset, nchars) - 1) / SZ_PIXEL + 1)
+		    return (bp)
+	    }
+	    return (impgs$t (im, long(1), IM_LEN(im,1), 1))
+	}
+end