25     """Back-end for display objects. 
   30         The display object that we're providing the implementation for 
   42         """Close the display, cleaning up any allocated resources 
   44         if hasattr(self, 
"verbose") 
and self.
verbose and hasattr(self, 
"display"):
 
   45             print(
"virtual[%s]._close()" % (self.frame))
 
   47     def _buffer(self, enable=True):
 
   48         """Enable or disable buffering of writes to the display 
   53             `True` or `False`, as appropriate 
   56             print(
"virtual[%s]._buffer(%s)" % (self.frame, enable))
 
   58     def _dot(self, symb, c, r, size, ctype, *args, **kwargs):
 
   59         """Draw a symbol at (c, r) 
   64             The desired symbol. See `dot` for details 
   70             Size of symbol, in pixels 
   72             The desired color, either e.g. `lsst.afw.display.RED` or a color name known to X11 
   74             Extra arguments to backend 
   76             Extra keyword arguments to backend 
   79             print(
"virtual[%s]._dot('%s', %.2f, %.2f, size=%g, ctype=%s, %s, %s)" %
 
   80                   (self.frame, symb, c, r, size, ctype, args, kwargs))
 
   82     def _drawLines(self, points, ctype):
 
   83         """Draw line defined by the list points 
   87         points : `list` of `tuple` of `float` 
   88             A list of 0-indexed positions [(x, y), (x, y), ...] 
   90             The desired color, either e.g. `lsst.afw.display.RED` or a color name known to X11 
   93             print(
"virtual[%s]._drawLines(%s, ctype=%s)" %
 
   94                   (self.frame, points, ctype))
 
   97         """Erase all glyphs drawn on display 
  100             print(
"virtual[%s]._erase()" % (self.frame))
 
  103         """Flush any I/O buffers 
  106             print(
"virtual[%s]._flush()" % self.frame)
 
  108     def _setCallback(self, what, func):
 
  110             print(
"setCallback %s -> %s" % (what, func))
 
  113         """Return an event generated by a keypress or mouse click 
  115         from .interface 
import Event
 
  119             print(
"virtual[%s]._getEvent() -> %s" % (self.frame, ev))
 
  123     def _getMaskTransparency(self):
 
  124         """Return the mask transparency for a display 
  127             print(
"virtual[%s]._getMaskTransparency()" % self.frame)
 
  129     def _mtv(self, image, wcs=None, mask=None, title=""):
 
  130         """Display an image and maybe a mask overlay on a display 
  134         image : `lsst.afw.image.Image` 
  135             `~lsst.afw.image.Image` to display 
  136         mask : `lsst.afw.image.Mask` 
  137             `~lsst.afw.image.Mask` to display 
  138         wcs : `lsst.afw.geom.SkyWcs` 
  139             A Wcs to associate with data 
  141             Name to display with the data 
  144             print(
"virtual[%s]._mtv(image=%s, mask=%s, wcs=%s, title=\"%s\")" %
 
  145                   (self.frame, 
"Image" if image 
else None,
 
  146                    "Mask" if mask 
else None, 
"Wcs" if wcs 
else None, title))
 
  148     def _setImageColormap(self, cmap):
 
  149         """Set the desired colormap 
  154             the name of a colormap (e.g. "gray") or a backend-specific object 
  157             print(
"virtual[%s]._setImageColormap(cmap=\"%s\")" % (self.frame, cmap))
 
  159     def _setMaskTransparency(self, transparency, maskplane):
 
  160         """Set the transparency of a maskplane 
  164         transparency : `float` 
  165             The desired transparency, in the range [0, 100] 
  167             The maskplane to set (None: all) 
  170             print(
"virtual[%s]._setMaskTransparency(%g, maskplane=\"%s\")" %
 
  171                   (self.frame, transparency, maskplane))
 
  173     def _scale(self, algorithm, min, max, *args, unit=None, **kwargs):
 
  174         """Set the scaling from DN to displayed pixels 
  179             Scaling algorithm (e.g. linear) 
  181             The minimum value of the stretch (or "zscale" or "minmax") 
  183             The maximum value of the stretch 
  185             Units for min and max (e.g. Percent, Absolute, Sigma) 
  187             Optional arguments to the backend 
  189             Optional keyword arguments to the backend 
  192             print(
"virtual[%s]._scale(%s, %s, %s, %s, %s, %s)" % (self.frame, algorithm,
 
  193                                                                   min, max, unit, args, kwargs))
 
  196         """Show the requested display 
  199             print(
"virtual[%s]._show()" % self.frame)
 
  201     def _pan(self, r, c):
 
  202         """Pan to a row and column 
  207             Desired column (x) position 
  209             Desired row (y) position 
  212             print(
"virtual[%s]._pan(%.2f, %.2f)" % (self.frame, r, c))
 
  214     def _zoom(self, zoomfac):
 
  223             print(
"virtual[%s]._zoom(%g)" % (self.frame, zoomfac))