I have a cunning plan

[ci skip]

CHANGES.rst

@@ -10,6 +10,9 @@ Cubeviz
 Imviz
 ^^^^^
 
+- New Simple Image Rotation plugin to rotate the celestial axes of
+  images if they have valid WCS. [#1340]
+
 Mosviz
 ^^^^^^
 

docs/imviz/plugins.rst

@@ -251,3 +251,28 @@ The columns are as follow:
 
 Once you have the results in a table, you can further manipulated them as
 documented in :ref:`astropy:astropy-table`.
+
+
+.. _rotate-image-simple:
+
+Simple Image Rotation
+=====================
+
+.. warning::
+
+    Distortion is ignored, so using this plugin on distorted data is
+    not recommended.
+
+.. note::
+
+    Zoom box in :ref:`imviz-compass` will not show when rotation mode is on.
+
+This plugins rotates image(s) by its celestial axes by the given angle.
+You can toggle the rotation mode on and off. When on, by default, it
+will align image(s) to N-up and E-left orientation.
+If rotation mode is on but an image does not have a valid WCS, it will
+not be rotated.
+
+Given that this plugin affects the linking of the entire data collection
+in Imviz, it is not recommended to keep toggling this on and off
+continuously. You might also notice some lag when a lot of images are loaded.

jdaviz/configs/imviz/imviz.yaml

@@ -25,6 +25,7 @@ tray:
   - imviz-compass
   - imviz-line-profile-xy
   - imviz-aper-phot-simple
+  - imviz-rotate-image
   - g-export-plot
 viewer_area:
   - container: col

jdaviz/configs/imviz/plugins/__init__.py

@@ -7,3 +7,4 @@
 from .compass import *  # noqa
 from .aper_phot_simple import *  # noqa
 from .line_profile_xy import *  # noqa
+from .rotate_image import *  # noqa

jdaviz/configs/imviz/plugins/rotate_image/__init__.py

@@ -0,0 +1 @@
+from .rotate_image import *  # noqa

jdaviz/configs/imviz/plugins/rotate_image/rotate_image.py

@@ -0,0 +1,40 @@
+from traitlets import Bool, observe
+
+from jdaviz.core.custom_traitlets import FloatHandleEmpty
+from jdaviz.core.registries import tray_registry
+from jdaviz.core.template_mixin import TemplateMixin
+
+__all__ = ['RotateImageSimple']
+
+
+@tray_registry('imviz-rotate-image', label="Simple Image Rotation")
+class RotateImageSimple(TemplateMixin):
+    template_file = __file__, "rotate_image.vue"
+
+    rotate_mode_on = Bool(False).tag(sync=True)
+    angle = FloatHandleEmpty(0).tag(sync=True)
+
+    @observe('angle')
+    def vue_rotate_image(*args, **kwargs):
+        pass  # TODO
+
+        # Create a small dummy image
+
+        # Create a fake WCS with desired orientation
+
+        # Add it into data collection
+
+        # Make it reference. Remember which one as old reference.
+        # If no API to make something reference, remove everything, readd
+        # with it first, and relink.
+
+        # When angle changes, is updating Data.coords with new WCS good enough?
+
+        # Find a way to hide this image from Data dropdown, blink, etc
+
+        # When toggle off, discard this from data_collection and restore old reference.
+
+        # Have compass hide zoom box when rotate_mode_on is True
+        # and un-hide it when False.
+
+        # Write tests.

jdaviz/configs/imviz/plugins/rotate_image/rotate_image.vue

@@ -0,0 +1,28 @@
+<template>
+  <j-tray-plugin>
+    <v-row>
+      <j-docs-link :link="'https://jdaviz.readthedocs.io/en/'+vdocs+'/'+config+'/plugins.html#simple-image-rotation'">Rotate image N-up/E-left.</j-docs-link>
+    </v-row>
+
+    <v-row>
+      <v-switch
+        label="Rotate celestial axes"
+        hint="Toggle N-E axes rotation on or off"
+        v-model="rotate_mode_on"
+        persistent-hint>
+      </v-switch>
+    </v-row>
+
+    <v-row v-if="rotate_mode_on">
+      <v-col>
+        <v-text-field
+          v-model='angle'
+          type="number"
+          label="Angle"
+          hint="Rotation angle of N-axis in degree clockwise (0 is N-up)"
+        ></v-text-field>
+      </v-col>
+    </v-row>
+
+  </j-tray-plugin>
+</template>

licenses/MPDAF_LICENSE.txt

@@ -0,0 +1,28 @@
+Copyright (c) 2010-2019 CNRS / Centre de Recherche Astrophysique de Lyon
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its contributors
+   may be used to endorse or promote products derived from this software without
+   specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.