From 39f06923750d55c6f5b5450bde1bc8295c4c114c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maximilian=20N=C3=B6the?= <maximilian.noethe@tu-dortmund.de>
Date: Wed, 19 Dec 2018 17:17:10 +0100
Subject: [PATCH 1/2] Add script to export FACT camera geometry for ctapipe

---
 examples/export_ctapipe_camera_geometry.py | 30 ++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 examples/export_ctapipe_camera_geometry.py

diff --git a/examples/export_ctapipe_camera_geometry.py b/examples/export_ctapipe_camera_geometry.py
new file mode 100644
index 0000000..0a8c872
--- /dev/null
+++ b/examples/export_ctapipe_camera_geometry.py
@@ -0,0 +1,30 @@
+from astropy.table import Table
+from fact.instrument import get_pixel_coords
+import astropy.units as u
+import numpy as np
+
+x, y = get_pixel_coords()
+x = (x * u.mm).to(u.m)
+y = (y * u.mm).to(u.m)
+pix_id = np.arange(1440)
+
+radius = np.sqrt(np.diff(x)**2 + np.diff(y)**2).min() / 2
+pix_area = 1.5 * np.sqrt(3) * radius**2
+
+
+t = Table()
+
+t['pix_id'] = pix_id
+t['pix_x'] = -y
+t['pix_y'] = -x
+t['pix_area'] = pix_area
+t.meta['TAB_TYPE'] = 'ctapipe.instrument.CameraGeometry'
+t.meta['PIX_TYPE'] = 'hexagonal'
+t.meta['CAM_ID'] = 'FACT'
+t.meta['PIX_ROT'] = 0.0
+t.meta['CAM_ROT'] = 0.0
+t.meta['SOURCE'] = 'pyfact'
+t.meta['TAB_VER'] = '1'
+
+
+t.write('FACT.camgeom.fits.gz', overwrite=True)

From 62e481633a8e20e46b23a3f1c07007760f92f399 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maximilian=20N=C3=B6the?= <maximilian.noethe@tu-dortmund.de>
Date: Tue, 12 Feb 2019 13:31:56 +0100
Subject: [PATCH 2/2] Add comment about coord systems

---
 examples/export_ctapipe_camera_geometry.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/examples/export_ctapipe_camera_geometry.py b/examples/export_ctapipe_camera_geometry.py
index 0a8c872..3450a11 100644
--- a/examples/export_ctapipe_camera_geometry.py
+++ b/examples/export_ctapipe_camera_geometry.py
@@ -15,8 +15,11 @@
 t = Table()
 
 t['pix_id'] = pix_id
+
+# convert from fact coords into hess/cta camera coordinate system
 t['pix_x'] = -y
 t['pix_y'] = -x
+
 t['pix_area'] = pix_area
 t.meta['TAB_TYPE'] = 'ctapipe.instrument.CameraGeometry'
 t.meta['PIX_TYPE'] = 'hexagonal'