[Feature] Wiring frb buffers with plot_window

doc/source/visualizing/callbacks.rst

@@ -887,3 +887,20 @@ Overplot the Path of a Ray
    p.annotate_ray(oray)
    p.annotate_ray(ray)
    p.save()
+
+
+Applying filters on the final image
+-----------------------------------
+
+It is also possible to operate on the plotted image directly by using
+one of the fixed resolution buffer filter as described in
+:ref:`frb-filters`.
+
+.. python-script::
+
+   import yt
+
+   ds = yt.load('IsolatedGalaxy/galaxy0030/galaxy0030')
+   p = yt.SlicePlot(ds, 'z', 'density')
+   p.frb.apply_gauss_beam(sigma=30)
+   p.save()

doc/source/visualizing/manual_plotting.rst

@@ -91,7 +91,7 @@ using them matters.
    ds = yt.load("IsolatedGalaxy/galaxy0030/galaxy0030")
    slc = ds.slice("z", 0.5)
    frb = slc.to_frb((20, "kpc"), 512)
-   frb.apply_gauss_beam(nbeam=30, sigma=2.0)
+   frb.apply_gauss_beam(sigma=2.0)
    frb.apply_white_noise(5e-23)
    plt.imshow(frb["gas", "density"].d)
    plt.savefig("frb_filters.png")
@@ -101,13 +101,12 @@ Currently available filters:
 Gaussian Smoothing
 ~~~~~~~~~~~~~~~~~~
 
-.. function:: apply_gauss_beam(self, nbeam=30, sigma=2.0)
+.. function:: apply_gauss_beam(self, sigma=2.0)
 
    (This is a proxy for
    :class:`~yt.visualization.fixed_resolution_filters.FixedResolutionBufferGaussBeamFilter`.)
 
-    This filter convolves the FRB with 2d Gaussian that is "nbeam" pixel wide
-    and has standard deviation "sigma".
+    This filter convolves the FRB with 2d Gaussian that has standard deviation "sigma".
 
 White Noise
 ~~~~~~~~~~~

yt/visualization/fixed_resolution.py

@@ -87,7 +87,15 @@ class FixedResolutionBuffer:
         ("index", "dtheta"),
     )
 
-    def __init__(self, data_source, bounds, buff_size, antialias=True, periodic=False):
+    def __init__(
+        self,
+        data_source,
+        bounds,
+        buff_size,
+        antialias=True,
+        periodic=False,
+        filters=None,
+    ):
         self.data_source = data_source
         self.ds = data_source.ds
         self.bounds = bounds
@@ -97,6 +105,8 @@ def __init__(self, data_source, bounds, buff_size, antialias=True, periodic=Fals
         self._filters = []
         self.axis = data_source.axis
         self.periodic = periodic
+        self._data_valid = False
+        self._filters = filters if filters else []
 
         ds = getattr(data_source, "ds", None)
         if ds is not None:
@@ -122,7 +132,7 @@ def __delitem__(self, item):
         del self.data[item]
 
     def __getitem__(self, item):
-        if item in self.data:
+        if item in self.data and self._data_valid:
             return self.data[item]
         mylog.info(
             "Making a fixed resolution buffer of (%s) %d by %d",
@@ -162,6 +172,7 @@ def __getitem__(self, item):
 
         ia = ImageArray(buff, units=units, info=self._get_info(item))
         self.data[item] = ia
+        self._data_valid = True
         return self.data[item]
 
     def __setitem__(self, item, val):
@@ -539,14 +550,14 @@ class CylindricalFixedResolutionBuffer(FixedResolutionBuffer):
     that supports non-aligned input data objects, primarily cutting planes.
     """
 
-    def __init__(self, data_source, radius, buff_size, antialias=True):
-
+    def __init__(self, data_source, radius, buff_size, antialias=True, filters=None):
         self.data_source = data_source
         self.ds = data_source.ds
         self.radius = radius
         self.buff_size = buff_size
         self.antialias = antialias
         self.data = {}
+        self._filters = filters if filters else []
 
         ds = getattr(data_source, "ds", None)
         if ds is not None:
@@ -576,12 +587,6 @@ class OffAxisProjectionFixedResolutionBuffer(FixedResolutionBuffer):
     that supports off axis projections.  This calls the volume renderer.
     """
 
-    def __init__(self, data_source, bounds, buff_size, antialias=True, periodic=False):
-        self.data = {}
-        FixedResolutionBuffer.__init__(
-            self, data_source, bounds, buff_size, antialias, periodic
-        )
-
     def __getitem__(self, item):
         if item in self.data:
             return self.data[item]
@@ -628,11 +633,16 @@ class ParticleImageBuffer(FixedResolutionBuffer):
 
     """
 
-    def __init__(self, data_source, bounds, buff_size, antialias=True, periodic=False):
-        self.data = {}
-        FixedResolutionBuffer.__init__(
-            self, data_source, bounds, buff_size, antialias, periodic
-        )
+    def __init__(
+        self,
+        data_source,
+        radius,
+        buff_size,
+        antialias=True,
+        periodic=False,
+        filters=None,
+    ):
+        super().__init__(data_source, radius, buff_size, antialias, periodic, filters)
 
         # set up the axis field names
         axis = self.axis

yt/visualization/fixed_resolution_filters.py

@@ -2,13 +2,18 @@
 
 import numpy as np
 
+from yt._maintenance.deprecation import issue_deprecation_warning
+
 filter_registry = {}
 
 
 def apply_filter(f):
     @wraps(f)
     def newfunc(*args, **kwargs):
-        args[0]._filters.append((f.__name__, (args, kwargs)))
+        frb = args[0]
+        frb._filters.append((f.__name__, (args, kwargs)))
+        # Invalidate the data of the frb to force its regeneration
+        frb._data_valid = False
         return args[0]
 
     return newfunc
@@ -37,33 +42,34 @@ class FixedResolutionBufferGaussBeamFilter(FixedResolutionBufferFilter):
     """
     This filter convolves
     :class:`yt.visualization.fixed_resolution.FixedResolutionBuffer` with
-    2d gaussian that is 'nbeam' pixels wide and has standard deviation
-    'sigma'.
+    2d gaussian that has standard deviation 'sigma'. Extra arguments
+    are directly passed to `scipy.ndimage.gaussian_filter`.
     """
 
     _filter_name = "gauss_beam"
 
-    def __init__(self, nbeam=30, sigma=2.0):
-        self.nbeam = nbeam
+    def __init__(self, sigma=2.0, truncate=4.0, **kwargs):
+        if "nbeam" in kwargs:
+            issue_deprecation_warning(
+                "The `nbeam` argument has been deprecated and should be replaced by "
+                "the `truncate` argument where `truncate=nbeam/sigma`."
+            )
+            truncate = kwargs["nbeam"] / sigma
+
         self.sigma = sigma
+        self.truncate = truncate
+        self.extra_args = kwargs
 
     def apply(self, buff):
         from yt.utilities.on_demand_imports import _scipy
 
-        hnbeam = self.nbeam // 2
-        sigma = self.sigma
-
-        l = np.linspace(-hnbeam, hnbeam, num=self.nbeam + 1)
-        x, y = np.meshgrid(l, l)
-        g2d = (1.0 / (sigma * np.sqrt(2.0 * np.pi))) * np.exp(
-            -((x / sigma) ** 2 + (y / sigma) ** 2) / (2 * sigma ** 2)
+        spl = _scipy.ndimage.gaussian_filter(
+            buff,
+            self.sigma,
+            truncate=self.truncate,
+            **self.extra_args,
         )
-        g2d /= g2d.max()
-
-        npm, nqm = np.shape(buff)
-        spl = _scipy.signal.convolve(buff, g2d)
-
-        return spl[hnbeam : npm + hnbeam, hnbeam : nqm + hnbeam]
+        return spl
 
 
 class FixedResolutionBufferWhiteNoiseFilter(FixedResolutionBufferFilter):

yt/visualization/plot_container.py

@@ -60,8 +60,10 @@ def invalidate_data(f):
     @wraps(f)
     def newfunc(*args, **kwargs):
         rv = f(*args, **kwargs)
-        args[0]._data_valid = False
-        args[0]._plot_valid = False
+        plot = args[0]
+        # if plot._frb is not None:
+        #   plot._frb._data_valid = False
+        plot._plot_valid = False
         return rv
 
     return newfunc
@@ -94,16 +96,15 @@ def newfunc(*args, **kwargs):
 def validate_plot(f):
     @wraps(f)
     def newfunc(*args, **kwargs):
-        if hasattr(args[0], "_data_valid"):
-            if not args[0]._data_valid:
-                args[0]._recreate_frb()
-        if hasattr(args[0], "_profile_valid"):
-            if not args[0]._profile_valid:
-                args[0]._recreate_profile()
-        if not args[0]._plot_valid:
+        plot = args[0]
+        if hasattr(plot, "data_is_valid") and not plot.data_is_valid:
+            plot._recreate_frb()
+        if hasattr(plot, "_profile_valid") and not plot._profile_valid:
+            plot._recreate_profile()
+        if not plot._plot_valid:
             # it is the responsibility of _setup_plots to
-            # call args[0].run_callbacks()
-            args[0]._setup_plots()
+            # call plot.run_callbacks()
+            plot._setup_plots()
         rv = f(*args, **kwargs)
         return rv
 
@@ -428,7 +429,10 @@ def _switch_ds(self, new_ds, data_source=None):
             new_object = getattr(new_ds, name)(**kwargs)
 
         self.data_source = new_object
-        self._data_valid = self._plot_valid = False
+
+        if self._frb is not None:
+            self._frb._data_valid = False
+        self._plot_valid = False
 
         for d in "xyz":
             lim_name = d + "lim"