JAL-3763 refactored getCoveringMapping for virtual feature discovery
[jalview.git] / src / jalview / viewmodel / seqfeatures / FeatureRendererModel.java
index 284ee4f..8f513c9 100644 (file)
  */
 package jalview.viewmodel.seqfeatures;
 
-import jalview.api.AlignViewportI;
-import jalview.api.FeatureColourI;
-import jalview.api.FeaturesDisplayedI;
-import jalview.datamodel.AlignmentI;
-import jalview.datamodel.SequenceFeature;
-import jalview.datamodel.SequenceI;
-import jalview.renderer.seqfeatures.FeatureRenderer;
-import jalview.schemes.FeatureColour;
-import jalview.util.ColorUtils;
-
 import java.awt.Color;
 import java.beans.PropertyChangeListener;
 import java.beans.PropertyChangeSupport;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Hashtable;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 
-public abstract class FeatureRendererModel implements
-        jalview.api.FeatureRenderer
+import jalview.api.AlignViewportI;
+import jalview.api.FeatureColourI;
+import jalview.api.FeaturesDisplayedI;
+import jalview.datamodel.AlignedCodonFrame;
+import jalview.datamodel.AlignedCodonFrame.SequenceToSequenceMapping;
+import jalview.datamodel.AlignmentI;
+import jalview.datamodel.MappedFeatures;
+import jalview.datamodel.SearchResultMatchI;
+import jalview.datamodel.SearchResults;
+import jalview.datamodel.SearchResultsI;
+import jalview.datamodel.SequenceFeature;
+import jalview.datamodel.SequenceI;
+import jalview.datamodel.features.FeatureMatcherSetI;
+import jalview.datamodel.features.SequenceFeatures;
+import jalview.renderer.seqfeatures.FeatureRenderer;
+import jalview.schemes.FeatureColour;
+import jalview.util.ColorUtils;
+
+public abstract class FeatureRendererModel
+        implements jalview.api.FeatureRenderer
 {
+  /*
+   * a data bean to hold one row of feature settings from the gui
+   */
+  public static class FeatureSettingsBean
+  {
+    public final String featureType;
 
-  /**
+    public final FeatureColourI featureColour;
+
+    public final FeatureMatcherSetI filter;
+
+    public final Boolean show;
+
+    public FeatureSettingsBean(String type, FeatureColourI colour,
+            FeatureMatcherSetI theFilter, Boolean isShown)
+    {
+      featureType = type;
+      featureColour = colour;
+      filter = theFilter;
+      show = isShown;
+    }
+  }
+
+  /*
    * global transparency for feature
    */
   protected float transparency = 1.0f;
 
-  protected Map<String, FeatureColourI> featureColours = new ConcurrentHashMap<String, FeatureColourI>();
+  /*
+   * colour scheme for each feature type
+   */
+  protected Map<String, FeatureColourI> featureColours = new ConcurrentHashMap<>();
 
-  protected Map<String, Boolean> featureGroups = new ConcurrentHashMap<String, Boolean>();
+  /*
+   * visibility flag for each feature group
+   */
+  protected Map<String, Boolean> featureGroups = new ConcurrentHashMap<>();
+
+  /*
+   * filters for each feature type
+   */
+  protected Map<String, FeatureMatcherSetI> featureFilters = new HashMap<>();
 
   protected String[] renderOrder;
 
   Map<String, Float> featureOrder = null;
 
-  protected PropertyChangeSupport changeSupport = new PropertyChangeSupport(
-          this);
-
   protected AlignViewportI av;
 
+  private PropertyChangeSupport changeSupport = new PropertyChangeSupport(
+          this);
+
   @Override
   public AlignViewportI getViewport()
   {
@@ -99,6 +140,7 @@ public abstract class FeatureRendererModel implements
     this.renderOrder = frs.renderOrder;
     this.featureGroups = frs.featureGroups;
     this.featureColours = frs.featureColours;
+    this.featureFilters = frs.featureFilters;
     this.transparency = frs.transparency;
     this.featureOrder = frs.featureOrder;
     if (av != null && av != fr.getViewport())
@@ -155,7 +197,7 @@ public abstract class FeatureRendererModel implements
     {
       av.setFeaturesDisplayed(fdi = new FeaturesDisplayed());
     }
-    List<String> nft = new ArrayList<String>();
+    List<String> nft = new ArrayList<>();
     for (String featureType : featureTypes)
     {
       if (!fdi.isRegistered(featureType))
@@ -191,7 +233,7 @@ public abstract class FeatureRendererModel implements
     renderOrder = neworder;
   }
 
-  protected Map<String, float[][]> minmax = new Hashtable<String, float[][]>();
+  protected Map<String, float[][]> minmax = new Hashtable<>();
 
   public Map<String, float[][]> getMinMax()
   {
@@ -214,7 +256,8 @@ public abstract class FeatureRendererModel implements
       if (r[0] != 0 || mm[0] < 0.0)
       {
         r[0] = 1;
-        r[1] = (byte) ((int) 128.0 + 127.0 * (sequenceFeature.score / mm[1]));
+        r[1] = (byte) ((int) 128.0
+                + 127.0 * (sequenceFeature.score / mm[1]));
       }
       else
       {
@@ -256,17 +299,27 @@ public abstract class FeatureRendererModel implements
       {
         firing = Boolean.TRUE;
         findAllFeatures(true); // add all new features as visible
-        changeSupport.firePropertyChange("changeSupport", null, null);
+        notifyFeaturesChanged();
         firing = Boolean.FALSE;
       }
     }
   }
 
   @Override
-  public List<SequenceFeature> findFeaturesAtRes(SequenceI sequence, int res)
+  public void notifyFeaturesChanged()
   {
-    List<SequenceFeature> result = new ArrayList<SequenceFeature>();
-    if (!av.areFeaturesDisplayed())
+    changeSupport.firePropertyChange("changeSupport", null, null);
+  }
+
+  @Override
+  public List<SequenceFeature> findFeaturesAtColumn(SequenceI sequence, int column)
+  {
+    /*
+     * include features at the position provided their feature type is 
+     * displayed, and feature group is null or marked for display
+     */
+    List<SequenceFeature> result = new ArrayList<>();
+    if (!av.areFeaturesDisplayed() || getFeaturesDisplayed() == null)
     {
       return result;
     }
@@ -275,17 +328,16 @@ public abstract class FeatureRendererModel implements
             .getVisibleFeatures();
     String[] visibleTypes = visibleFeatures
             .toArray(new String[visibleFeatures.size()]);
+    List<SequenceFeature> features = sequence.findFeatures(column, column,
+            visibleTypes);
 
     /*
-     * include features at the position provided their feature type is 
-     * displayed, and feature group is null or marked for display
+     * include features unless they are hidden (have no colour), based on 
+     * feature group visibility, or a filter or colour threshold
      */
-    List<SequenceFeature> features = sequence.getFeatures().findFeatures(
-            res, res, visibleTypes);
-
     for (SequenceFeature sf : features)
     {
-      if (!featureGroupNotShown(sf))
+      if (getColour(sf) != null)
       {
         result.add(sf);
       }
@@ -319,7 +371,7 @@ public abstract class FeatureRendererModel implements
     }
     FeaturesDisplayedI featuresDisplayed = av.getFeaturesDisplayed();
 
-    Set<String> oldfeatures = new HashSet<String>();
+    Set<String> oldfeatures = new HashSet<>();
     if (renderOrder != null)
     {
       for (int i = 0; i < renderOrder.length; i++)
@@ -330,48 +382,19 @@ public abstract class FeatureRendererModel implements
         }
       }
     }
-    // <<<<<<< HEAD
-    //
-    // =======
-    // if (minmax == null)
-    // {
-    // minmax = new Hashtable<String, float[][]>();
-    // }
-    //
-    // Set<String> oldGroups = new HashSet<String>(featureGroups.keySet());
-    // >>>>>>> refs/heads/develop
+
     AlignmentI alignment = av.getAlignment();
-    List<String> allfeatures = new ArrayList<String>(); // or HashSet?
+    List<String> allfeatures = new ArrayList<>();
 
     for (int i = 0; i < alignment.getHeight(); i++)
     {
       SequenceI asq = alignment.getSequenceAt(i);
       for (String group : asq.getFeatures().getFeatureGroups(true))
       {
-        // <<<<<<< HEAD
-        /*
-         * features in null group are always displayed; other groups
-         * keep their current visibility; new groups as 'newMadeVisible'
-         */
         boolean groupDisplayed = true;
         if (group != null)
-        // =======
-        // continue;
-        // }
-        //
-        // int index = 0;
-        // while (index < features.length)
-        // {
-        // String fgrp = features[index].getFeatureGroup();
-        // oldGroups.remove(fgrp);
-        // if (!featuresDisplayed.isRegistered(features[index].getType()))
-        // >>>>>>> refs/heads/develop
         {
-          // <<<<<<< HEAD
           if (featureGroups.containsKey(group))
-          // =======
-          // if (fgrp != null)
-          // >>>>>>> refs/heads/develop
           {
             groupDisplayed = featureGroups.get(group);
           }
@@ -397,11 +420,8 @@ public abstract class FeatureRendererModel implements
       }
     }
 
-    /*
-    //<<<<<<< HEAD
-     * mark any new feature types as visible
-     */
-    Collections.sort(allfeatures, String.CASE_INSENSITIVE_ORDER);
+    // uncomment to add new features in alphebetical order (but JAL-2575)
+    // Collections.sort(allfeatures, String.CASE_INSENSITIVE_ORDER);
     if (newMadeVisible)
     {
       for (String type : allfeatures)
@@ -412,14 +432,6 @@ public abstract class FeatureRendererModel implements
           setOrder(type, 0);
         }
       }
-      // =======
-      // * oldGroups now consists of groups that no longer
-      // * have any feature in them - remove these
-      // */
-      // for (String grp : oldGroups)
-      // {
-      // featureGroups.remove(grp);
-      // >>>>>>> refs/heads/develop
     }
 
     updateRenderOrder(allfeatures);
@@ -452,7 +464,7 @@ public abstract class FeatureRendererModel implements
      */
     if (minmax == null)
     {
-      minmax = new Hashtable<String, float[][]>();
+      minmax = new Hashtable<>();
     }
     synchronized (minmax)
     {
@@ -489,7 +501,7 @@ public abstract class FeatureRendererModel implements
    */
   private void updateRenderOrder(List<String> allFeatures)
   {
-    List<String> allfeatures = new ArrayList<String>(allFeatures);
+    List<String> allfeatures = new ArrayList<>(allFeatures);
     String[] oldRender = renderOrder;
     renderOrder = new String[allfeatures.size()];
     boolean initOrders = (featureOrder == null);
@@ -502,7 +514,8 @@ public abstract class FeatureRendererModel implements
         {
           if (initOrders)
           {
-            setOrder(oldRender[j], (1 - (1 + (float) j) / oldRender.length));
+            setOrder(oldRender[j],
+                    (1 - (1 + (float) j) / oldRender.length));
           }
           if (allfeatures.contains(oldRender[j]))
           {
@@ -515,7 +528,8 @@ public abstract class FeatureRendererModel implements
               if (mmrange != null)
               {
                 FeatureColourI fc = featureColours.get(oldRender[j]);
-                if (fc != null && !fc.isSimpleColour() && fc.isAutoScaled())
+                if (fc != null && !fc.isSimpleColour() && fc.isAutoScaled()
+                        && !fc.isColourByAttribute())
                 {
                   fc.updateBounds(mmrange[0][0], mmrange[0][1]);
                 }
@@ -545,7 +559,8 @@ public abstract class FeatureRendererModel implements
         if (mmrange != null)
         {
           FeatureColourI fc = featureColours.get(newf[i]);
-          if (fc != null && !fc.isSimpleColour() && fc.isAutoScaled())
+          if (fc != null && !fc.isSimpleColour() && fc.isAutoScaled()
+                  && !fc.isColourByAttribute())
           {
             fc.updateBounds(mmrange[0][0], mmrange[0][1]);
           }
@@ -595,32 +610,11 @@ public abstract class FeatureRendererModel implements
     return fc;
   }
 
-  /**
-   * Returns the configured colour for a particular feature instance. This
-   * includes calculation of 'colour by label', or of a graduated score colour,
-   * if applicable. It does not take into account feature visibility or colour
-   * transparency.
-   * 
-   * @param feature
-   * @return
-   */
+  @Override
   public Color getColour(SequenceFeature feature)
   {
     FeatureColourI fc = getFeatureStyle(feature.getType());
-    return fc.getColor(feature);
-  }
-
-  /**
-   * Answers true unless the feature has a graduated colour scheme and the
-   * feature value lies outside the current threshold for display
-   * 
-   * @param sequenceFeature
-   * @return
-   */
-  protected boolean showFeature(SequenceFeature sequenceFeature)
-  {
-    FeatureColourI fc = getFeatureStyle(sequenceFeature.type);
-    return fc.isColored(sequenceFeature);
+    return getColor(feature, fc);
   }
 
   /**
@@ -632,7 +626,8 @@ public abstract class FeatureRendererModel implements
    */
   protected boolean showFeatureOfType(String type)
   {
-    return type == null ? false : av.getFeaturesDisplayed().isVisible(type);
+    return type == null ? false : (av.getFeaturesDisplayed() == null ? true
+            : av.getFeaturesDisplayed().isVisible(type));
   }
 
   @Override
@@ -667,9 +662,9 @@ public abstract class FeatureRendererModel implements
   {
     if (featureOrder == null)
     {
-      featureOrder = new Hashtable<String, Float>();
+      featureOrder = new Hashtable<>();
     }
-    featureOrder.put(type, new Float(position));
+    featureOrder.put(type, Float.valueOf(position));
     return position;
   }
 
@@ -701,32 +696,33 @@ public abstract class FeatureRendererModel implements
    * Replace current ordering with new ordering
    * 
    * @param data
-   *          { String(Type), Colour(Type), Boolean(Displayed) }
+   *          an array of { Type, Colour, Filter, Boolean }
    * @return true if any visible features have been reordered, else false
    */
-  public boolean setFeaturePriority(Object[][] data)
+  public boolean setFeaturePriority(FeatureSettingsBean[] data)
   {
     return setFeaturePriority(data, true);
   }
 
   /**
-   * Sets the priority order for features, with the highest priority (displayed
-   * on top) at the start of the data array
+   * Sets the priority order for features, with the highest priority (displayed on
+   * top) at the start of the data array
    * 
    * @param data
-   *          { String(Type), Colour(Type), Boolean(Displayed) }
+   *          an array of { Type, Colour, Filter, Boolean }
    * @param visibleNew
    *          when true current featureDisplay list will be cleared
-   * @return true if any visible features have been reordered or recoloured,
-   *         else false (i.e. no need to repaint)
+   * @return true if any visible features have been reordered or recoloured, else
+   *         false (i.e. no need to repaint)
    */
-  public boolean setFeaturePriority(Object[][] data, boolean visibleNew)
+  public boolean setFeaturePriority(FeatureSettingsBean[] data,
+          boolean visibleNew)
   {
     /*
      * note visible feature ordering and colours before update
      */
     List<String> visibleFeatures = getDisplayedFeatureTypes();
-    Map<String, FeatureColourI> visibleColours = new HashMap<String, FeatureColourI>(
+    Map<String, FeatureColourI> visibleColours = new HashMap<>(
             getFeatureColours());
 
     FeaturesDisplayedI av_featuresdisplayed = null;
@@ -738,7 +734,8 @@ public abstract class FeatureRendererModel implements
       }
       else
       {
-        av.setFeaturesDisplayed(av_featuresdisplayed = new FeaturesDisplayed());
+        av.setFeaturesDisplayed(
+                av_featuresdisplayed = new FeaturesDisplayed());
       }
     }
     else
@@ -758,9 +755,9 @@ public abstract class FeatureRendererModel implements
     {
       for (int i = 0; i < data.length; i++)
       {
-        String type = data[i][0].toString();
-        setColour(type, (FeatureColourI) data[i][1]);
-        if (((Boolean) data[i][2]).booleanValue())
+        String type = data[i].featureType;
+        setColour(type, data[i].featureColour);
+        if (data[i].show)
         {
           av_featuresdisplayed.setVisible(type);
         }
@@ -850,11 +847,12 @@ public abstract class FeatureRendererModel implements
   {
     // conflict between applet and desktop - featureGroups returns the map in
     // the desktop featureRenderer
-    return (featureGroups == null) ? Arrays.asList(new String[0]) : Arrays
-            .asList(featureGroups.keySet().toArray(new String[0]));
+    return (featureGroups == null) ? Arrays.asList(new String[0])
+            : Arrays.asList(featureGroups.keySet().toArray(new String[0]));
   }
 
-  public boolean checkGroupVisibility(String group, boolean newGroupsVisible)
+  public boolean checkGroupVisibility(String group,
+          boolean newGroupsVisible)
   {
     if (featureGroups == null)
     {
@@ -866,7 +864,7 @@ public abstract class FeatureRendererModel implements
     }
     if (newGroupsVisible)
     {
-      featureGroups.put(group, new Boolean(true));
+      featureGroups.put(group, Boolean.valueOf(true));
       return true;
     }
     return false;
@@ -884,7 +882,7 @@ public abstract class FeatureRendererModel implements
   {
     if (featureGroups != null)
     {
-      List<String> gp = new ArrayList<String>();
+      List<String> gp = new ArrayList<>();
 
       for (String grp : featureGroups.keySet())
       {
@@ -902,7 +900,7 @@ public abstract class FeatureRendererModel implements
   @Override
   public void setGroupVisibility(String group, boolean visible)
   {
-    featureGroups.put(group, new Boolean(visible));
+    featureGroups.put(group, Boolean.valueOf(visible));
   }
 
   @Override
@@ -914,7 +912,7 @@ public abstract class FeatureRendererModel implements
       for (String gst : toset)
       {
         Boolean st = featureGroups.get(gst);
-        featureGroups.put(gst, new Boolean(visible));
+        featureGroups.put(gst, Boolean.valueOf(visible));
         if (st != null)
         {
           rdrw = rdrw || (visible != st.booleanValue());
@@ -930,7 +928,7 @@ public abstract class FeatureRendererModel implements
   @Override
   public Map<String, FeatureColourI> getDisplayedFeatureCols()
   {
-    Map<String, FeatureColourI> fcols = new Hashtable<String, FeatureColourI>();
+    Map<String, FeatureColourI> fcols = new Hashtable<>();
     if (getViewport().getFeaturesDisplayed() == null)
     {
       return fcols;
@@ -958,7 +956,7 @@ public abstract class FeatureRendererModel implements
   public List<String> getDisplayedFeatureTypes()
   {
     List<String> typ = getRenderOrder();
-    List<String> displayed = new ArrayList<String>();
+    List<String> displayed = new ArrayList<>();
     FeaturesDisplayedI feature_disp = av.getFeaturesDisplayed();
     if (feature_disp != null)
     {
@@ -979,24 +977,13 @@ public abstract class FeatureRendererModel implements
   @Override
   public List<String> getDisplayedFeatureGroups()
   {
-    List<String> _gps = new ArrayList<String>();
-    boolean valid = false;
+    List<String> _gps = new ArrayList<>();
     for (String gp : getFeatureGroups())
     {
       if (checkGroupVisibility(gp, false))
       {
-        valid = true;
         _gps.add(gp);
       }
-      if (!valid)
-      {
-        return null;
-      }
-      else
-      {
-        // gps = new String[_gps.size()];
-        // _gps.toArray(gps);
-      }
     }
     return _gps;
   }
@@ -1008,7 +995,7 @@ public abstract class FeatureRendererModel implements
    * @param sequenceFeature
    * @return
    */
-  protected boolean featureGroupNotShown(final SequenceFeature sequenceFeature)
+  public boolean featureGroupNotShown(final SequenceFeature sequenceFeature)
   {
     return featureGroups != null
             && sequenceFeature.featureGroup != null
@@ -1018,4 +1005,290 @@ public abstract class FeatureRendererModel implements
                     .booleanValue();
   }
 
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+  public List<SequenceFeature> findFeaturesAtResidue(SequenceI sequence,
+          int fromResNo, int toResNo)
+  {
+    List<SequenceFeature> result = new ArrayList<>();
+    if (!av.areFeaturesDisplayed() || getFeaturesDisplayed() == null)
+    {
+      return result;
+    }
+
+    /*
+     * include features at the position provided their feature type is 
+     * displayed, and feature group is null or the empty string
+     * or marked for display
+     */
+    List<String> visibleFeatures = getDisplayedFeatureTypes();
+    String[] visibleTypes = visibleFeatures
+            .toArray(new String[visibleFeatures.size()]);
+    List<SequenceFeature> features = sequence.getFeatures().findFeatures(
+            fromResNo, toResNo, visibleTypes);
+  
+    for (SequenceFeature sf : features)
+    {
+      if (!featureGroupNotShown(sf) && getColour(sf) != null)
+      {
+        result.add(sf);
+      }
+    }
+    return result;
+  }
+
+  /**
+   * Removes from the list of features any whose group is not shown, or that are
+   * visible and duplicate the location of a visible feature of the same type.
+   * Should be used only for features of the same, simple, feature colour (which
+   * normally implies the same feature type). No filtering is done if
+   * transparency, or any feature filters, are in force.
+   * 
+   * @param features
+   */
+  public void filterFeaturesForDisplay(List<SequenceFeature> features)
+  {
+    /*
+     * don't remove 'redundant' features if 
+     * - transparency is applied (feature count affects depth of feature colour)
+     * - filters are applied (not all features may be displayable)
+     */
+    if (features.isEmpty() || transparency != 1f
+            || !featureFilters.isEmpty())
+    {
+      return;
+    }
+
+    SequenceFeatures.sortFeatures(features, true);
+    SequenceFeature lastFeature = null;
+
+    Iterator<SequenceFeature> it = features.iterator();
+    while (it.hasNext())
+    {
+      SequenceFeature sf = it.next();
+      if (featureGroupNotShown(sf))
+      {
+        it.remove();
+        continue;
+      }
+
+      /*
+       * a feature is redundant for rendering purposes if it has the
+       * same extent as another (so would just redraw the same colour);
+       * (checking type and isContactFeature as a fail-safe here, although
+       * currently they are guaranteed to match in this context)
+       */
+      if (lastFeature != null
+              && sf.getBegin() == lastFeature.getBegin()
+              && sf.getEnd() == lastFeature.getEnd()
+              && sf.isContactFeature() == lastFeature.isContactFeature()
+              && sf.getType().equals(lastFeature.getType()))
+      {
+        it.remove();
+      }
+      lastFeature = sf;
+    }
+  }
+
+  @Override
+  public Map<String, FeatureMatcherSetI> getFeatureFilters()
+  {
+    return featureFilters;
+  }
+
+  @Override
+  public void setFeatureFilters(Map<String, FeatureMatcherSetI> filters)
+  {
+    featureFilters = filters;
+  }
+
+  @Override
+  public FeatureMatcherSetI getFeatureFilter(String featureType)
+  {
+    return featureFilters.get(featureType);
+  }
+
+  @Override
+  public void setFeatureFilter(String featureType, FeatureMatcherSetI filter)
+  {
+    if (filter == null || filter.isEmpty())
+    {
+      featureFilters.remove(featureType);
+    }
+    else
+    {
+      featureFilters.put(featureType, filter);
+    }
+  }
+
+  /**
+   * Answers the colour for the feature, or null if the feature is excluded by
+   * feature group visibility, by filters, or by colour threshold settings. This
+   * method does not take feature visibility into account.
+   * 
+   * @param sf
+   * @param fc
+   * @return
+   */
+  public Color getColor(SequenceFeature sf, FeatureColourI fc)
+  {
+    /*
+     * is the feature group displayed?
+     */
+    if (featureGroupNotShown(sf))
+    {
+      return null;
+    }
+
+    /*
+     * does the feature pass filters?
+     */
+    if (!featureMatchesFilters(sf))
+    {
+      return null;
+    }
+  
+    return fc.getColor(sf);
+  }
+
+  /**
+   * Answers true if there no are filters defined for the feature type, or this
+   * feature matches the filters. Answers false if the feature fails to match
+   * filters.
+   * 
+   * @param sf
+   * @return
+   */
+  protected boolean featureMatchesFilters(SequenceFeature sf)
+  {
+    FeatureMatcherSetI filter = featureFilters.get(sf.getType());
+    return filter == null ? true : filter.matches(sf);
+  }
+
+  @Override
+  public MappedFeatures findComplementFeaturesAtResidue(
+          final SequenceI sequence, final int pos)
+  {
+    SequenceI ds = sequence.getDatasetSequence();
+    if (ds == null)
+    {
+      ds = sequence;
+    }
+    final char residue = ds.getCharAt(pos - ds.getStart());
+
+    List<SequenceFeature> found = new ArrayList<>();
+    List<AlignedCodonFrame> mappings = this.av.getAlignment()
+            .getCodonFrame(sequence);
+
+    /*
+     * fudge: if no mapping found, check the complementary alignment
+     * todo: only store in one place? StructureSelectionManager?
+     */
+    if (mappings.isEmpty())
+    {
+      mappings = this.av.getCodingComplement().getAlignment()
+              .getCodonFrame(sequence);
+    }
+
+    /*
+     * todo: direct lookup of CDS for peptide and vice-versa; for now,
+     * have to search through an unordered list of mappings for a candidate
+     */
+    SequenceToSequenceMapping mapping = null;
+    SequenceI mapFrom = null;
+
+    for (AlignedCodonFrame acf : mappings)
+    {
+      mapping = acf.getCoveringCodonMapping(ds);
+      if (mapping == null)
+      {
+        continue;
+      }
+      SearchResultsI sr = new SearchResults();
+      mapping.markMappedRegion(ds, pos, sr);
+      for (SearchResultMatchI match : sr.getResults())
+      {
+        int fromRes = match.getStart();
+        int toRes = match.getEnd();
+        mapFrom = match.getSequence();
+        List<SequenceFeature> fs = findFeaturesAtResidue(
+                mapFrom, fromRes, toRes);
+        for (SequenceFeature sf : fs)
+        {
+          if (!found.contains(sf))
+          {
+            found.add(sf);
+          }
+        }
+      }
+
+      /*
+       * just take the first mapped features we find
+       */
+      if (!found.isEmpty())
+      {
+        break;
+      }
+    }
+    if (found.isEmpty())
+    {
+      return null;
+    }
+
+    /*
+     * sort by renderorder (inefficiently but ok for small scale);
+     * NB this sorts 'on top' feature to end, for rendering
+     */
+    List<SequenceFeature> result = new ArrayList<>();
+    final int toAdd = found.size();
+    int added = 0;
+    for (String type : renderOrder)
+    {
+      for (SequenceFeature sf : found)
+      {
+        if (type.equals(sf.getType()))
+        {
+          result.add(sf);
+          added++;
+        }
+        if (added == toAdd)
+        {
+          break;
+        }
+      }
+    }
+    
+    return new MappedFeatures(mapping.getMapping(), mapFrom, pos, residue, result);
+  }
+
+  @Override
+  public boolean isVisible(SequenceFeature feature)
+  {
+    if (feature == null)
+    {
+      return false;
+    }
+    if (getFeaturesDisplayed() == null
+            || !getFeaturesDisplayed().isVisible(feature.getType()))
+    {
+      return false;
+    }
+    if (featureGroupNotShown(feature))
+    {
+      return false;
+    }
+    FeatureColourI fc = featureColours.get(feature.getType());
+    if (fc != null && fc.isOutwithThreshold(feature))
+    {
+      return false;
+    }
+    if (!featureMatchesFilters(feature))
+    {
+      return false;
+    }
+    return true;
+  }
+
 }