1 files changed, 28 insertions, 0 deletions
diff --git a/noao/twodspec/apextract/apgscur.x b/noao/twodspec/apextract/apgscur.x
new file mode 100644
index 00000000..5306ff9a
--- /dev/null
+++ b/noao/twodspec/apextract/apgscur.x
@@ -0,0 +1,28 @@
+include	"apertures.h"
+
+# AP_GSCUR -- Set the graphics cursor to the aperture given by the index.
+# It computes the position of the cursor for the specified dispersion line.
+
+procedure ap_gscur (index, gp, line, aps, y)
+
+int	index			# Index of aperture
+pointer	gp			# GIO pointer
+int	line			# Dispersion line
+pointer	aps[ARB]		# Apertures
+real	y			# Y cursor coordinate
+
+int	apaxis
+real	x
+pointer	ap
+
+real	ap_cveval()
+
+begin
+	if (index < 1 || IS_INDEF (y))
+	    return
+
+	ap = aps[index]
+	apaxis = AP_AXIS(ap)
+	x = AP_CEN(ap, apaxis) + ap_cveval (AP_CV(ap), real (line))
+	call gscur (gp, x, y)
+end