IDEA-148164 Add translucent thumb over error stripes in the project view tree

platform/platform-api/src/com/intellij/util/ui/ButtonlessScrollBarUI.java

@@ -637,9 +637,9 @@ public class ButtonlessScrollBarUI extends BasicScrollBarUI {
     if (alwaysShowTrack() || myMouseOverScrollbarExpandLevel > 0) {
       doPaintTrack(g, c, trackBounds);
     }
-    RegionPainter painter = UIUtil.getClientProperty(c, RegionPainter.BUTTONLESS_SCROLL_BAR_UI_EXTRA_TRACK);
+    RegionPainter<Object> painter = UIUtil.getClientProperty(c, RegionPainter.BUTTONLESS_SCROLL_BAR_UI_EXTRA_TRACK);
     if (painter != null) {
-      painter.paint(g, trackBounds.x, trackBounds.y, trackBounds.width, trackBounds.height);
+      painter.paint((Graphics2D)g, trackBounds.x, trackBounds.y, trackBounds.width, trackBounds.height, null);
     }
   }
 
@@ -698,9 +698,15 @@ public class ButtonlessScrollBarUI extends BasicScrollBarUI {
       paintMacThumb(g, thumbBounds);
     }
     else {
-      g.translate(thumbBounds.x, thumbBounds.y);
-      paintMaxiThumb((Graphics2D)g, thumbBounds);
-      g.translate(-thumbBounds.x, -thumbBounds.y);
+      RegionPainter<Integer> painter = UIUtil.getClientProperty(scrollbar, RegionPainter.BUTTONLESS_SCROLL_BAR_UI_MAXI_THUMB);
+      if (painter != null) {
+        painter.paint((Graphics2D)g, thumbBounds.x, thumbBounds.y, thumbBounds.width, thumbBounds.height, myThumbFadeColorShift);
+      }
+      else {
+        g.translate(thumbBounds.x, thumbBounds.y);
+        paintMaxiThumb((Graphics2D)g, thumbBounds);
+        g.translate(-thumbBounds.x, -thumbBounds.y);
+      }
     }
   }
 

platform/platform-api/src/com/intellij/util/ui/RegionPainter.java

@@ -16,35 +16,92 @@
 package com.intellij.util.ui;
 
 import com.intellij.openapi.util.Key;
-import com.intellij.util.ui.UIUtil;
 
-import java.awt.Graphics;
+import java.awt.Graphics2D;
 import java.awt.image.BufferedImage;
 
 /**
+ * The {@code RegionPainter} interface defines exactly one method, {@code paint}.
+ * It is used in situations where the developer can change the painting routine
+ * of a component without having to resort to subclassing the component.
+ * It is also generically useful when doing any form of painting delegation.
+ * <p>
+ * Painters are simply encapsulations of Java2D code and make it fairly trivial
+ * to reuse existing painters or to combine them together.
+ * Implementations of this interface are also trivial to write,
+ * such that if you can't find a painter that does what you need,
+ * you can write one with minimal effort.
+ *
  * @author Sergey.Malenkov
+ * @see com.sun.java.swing.Painter
  */
-public interface RegionPainter {
-  void paint(Graphics g, int x, int y, int width, int height);
+public interface RegionPainter<T> {
+  /**
+   * Renders to the given {@link Graphics2D} object.
+   *
+   * @param g      the {@code Graphics2D} object to render to
+   * @param x      X position of the area to paint
+   * @param y      Y position of the area to paint
+   * @param width  width of the area to paint
+   * @param height height of the area to paint
+   * @param object an optional configuration parameter
+   */
+  void paint(Graphics2D g, int x, int y, int width, int height, T object);
 
-  Key<RegionPainter> BUTTONLESS_SCROLL_BAR_UI_EXTRA_TRACK = Key.create("BUTTONLESS_SCROLL_BAR_UI_EXTRA_TRACK");
+  /**
+   * This key is used in the {@link ButtonlessScrollBarUI}
+   * to paint error stripes over the scrollbar track.
+   *
+   * @see ButtonlessScrollBarUI
+   * @see UIUtil#putClientProperty
+   */
+  Key<RegionPainter<Object>> BUTTONLESS_SCROLL_BAR_UI_EXTRA_TRACK = Key.create("BUTTONLESS_SCROLL_BAR_UI_EXTRA_TRACK");
 
-  class Image implements RegionPainter {
+  /**
+   * This key is used in the {@link ButtonlessScrollBarUI}
+   * to paint the scrollbar maxi thumb.
+   *
+   * @see ButtonlessScrollBarUI
+   * @see UIUtil#putClientProperty
+   */
+  Key<RegionPainter<Integer>> BUTTONLESS_SCROLL_BAR_UI_MAXI_THUMB = Key.create("BUTTONLESS_SCROLL_BAR_UI_MAXI_THUMB");
+
+  /**
+   * This class provides a caching functionality for a region painter.
+   */
+  class Image implements RegionPainter<Object> {
     private BufferedImage myImage;
 
+    /**
+     * This method is called for the cached image before {@code drawImage}.
+     * It should be overridden if the image must be updated without creating a new image.
+     *
+     * @param image the cached image to update
+     */
     protected void updateImage(BufferedImage image) {
     }
 
+    /**
+     * This method is called if the cached image is invalidated or it's size is changed.
+     * It must be overridden to paint on newly created image.
+     *
+     * @param width  width of the new image
+     * @param height height of the new image
+     * @return new {@link BufferedImage} object
+     */
     protected BufferedImage createImage(int width, int height) {
       return UIUtil.createImage(width, height, BufferedImage.TYPE_INT_ARGB);
     }
 
+    /**
+     * This method is called to invalidate the cached image.
+     */
     protected void invalidate() {
       myImage = null;
     }
 
     @Override
-    public void paint(Graphics g, int x, int y, int width, int height) {
+    public void paint(Graphics2D g, int x, int y, int width, int height, Object object) {
       if (width > 0 && width > 0) {
         if (myImage == null || width != myImage.getWidth() || height != myImage.getHeight()) {
           myImage = createImage(width, height);

platform/platform-impl/src/com/intellij/ui/stripe/ErrorStripe.java

@@ -15,15 +15,12 @@
  */
 package com.intellij.ui.stripe;
 
-import com.intellij.util.ui.RegionPainter;
-
 import java.awt.Color;
-import java.awt.Graphics;
 
 /**
  * @author Sergey.Malenkov
  */
-public final class ErrorStripe implements RegionPainter, Comparable<ErrorStripe> {
+public final class ErrorStripe implements Comparable<ErrorStripe> {
   private final Color myColor;
   private final int myLayer;
 
@@ -44,12 +41,6 @@ public final class ErrorStripe implements RegionPainter, Comparable<ErrorStripe>
     return myLayer;
   }
 
-  @Override
-  public void paint(Graphics g, int x, int y, int width, int height) {
-    g.setColor(myColor);
-    g.fillRect(x, y, width, height);
-  }
-
   @Override
   public int hashCode() {
     return myLayer + myColor.hashCode();

platform/platform-impl/src/com/intellij/ui/stripe/ErrorStripePainter.java

@@ -19,7 +19,6 @@ import com.intellij.util.ui.RegionPainter;
 
 import java.awt.AlphaComposite;
 import java.awt.Composite;
-import java.awt.Graphics;
 import java.awt.Graphics2D;
 import java.awt.image.BufferedImage;
 import java.util.Iterator;
@@ -232,12 +231,12 @@ public class ErrorStripePainter extends RegionPainter.Image {
   }
 
   @Override
-  public void paint(Graphics g, int x, int y, int width, int height) {
+  public void paint(Graphics2D g, int x, int y, int width, int height, Object object) {
     myImageY = y;
-    super.paint(g, x, y, width, height);
+    super.paint(g, x, y, width, height, object);
   }
 
-  private abstract static class Value implements RegionPainter {
+  private abstract static class Value {
     boolean myModified;
 
     abstract boolean set(ErrorStripe stripe);
@@ -246,6 +245,8 @@ public class ErrorStripePainter extends RegionPainter.Image {
 
     abstract ErrorStripe get();
 
+    abstract void paint(Graphics2D g, int x, int y, int width, int height);
+
     void paint(Graphics2D g, int x, int y, int width, int height, boolean force) {
       if (force || myModified) {
         if (!force) {
@@ -284,12 +285,13 @@ public class ErrorStripePainter extends RegionPainter.Image {
     }
 
     @Override
-    public void paint(Graphics g, int x, int y, int width, int height) {
+    void paint(Graphics2D g, int x, int y, int width, int height) {
       myModified = false;
       if (myStripe != null) {
         int thickness = myAlignment != null ? myMin + myGap : height;
         y += getOffset(height, thickness);
-        myStripe.paint(g, x, y, width, thickness - myGap);
+        g.setColor(myStripe.getColor());
+        g.fillRect(x, y, width, thickness - myGap);
       }
     }
   }
@@ -323,7 +325,7 @@ public class ErrorStripePainter extends RegionPainter.Image {
     }
 
     @Override
-    public void paint(Graphics g, int x, int y, int width, int height) {
+    void paint(Graphics2D g, int x, int y, int width, int height) {
       myModified = false;
       if (mySet != null) {
         Iterator<ErrorStripe> iterator = mySet.iterator();
@@ -333,13 +335,15 @@ public class ErrorStripePainter extends RegionPainter.Image {
             int count = Math.min(height / thickness, mySet.size());
             y += getOffset(height, thickness * count);
             do {
-              iterator.next().paint(g, x, y, width, thickness - myGap);
+              g.setColor(iterator.next().getColor());
+              g.fillRect(x, y, width, thickness - myGap);
               y += thickness;
             }
             while (--count > 0 && iterator.hasNext());
           }
           else {
-            iterator.next().paint(g, x, y, width, thickness - myGap);
+            g.setColor(iterator.next().getColor());
+            g.fillRect(x, y, width, thickness - myGap);
           }
         }
       }

platform/platform-impl/src/com/intellij/ui/stripe/ExtraErrorStripePainter.java

@@ -15,7 +15,7 @@
  */
 package com.intellij.ui.stripe;
 
-import java.awt.Graphics;
+import java.awt.Graphics2D;
 
 /**
  * @author Sergey.Malenkov
@@ -38,7 +38,7 @@ public class ExtraErrorStripePainter extends ErrorStripePainter {
   }
 
   public int getGroupGap() {
-    return myGroupGap;
+    return myGroupGap != null ? myGroupGap : getMinimalThickness();
   }
 
   public void setGroupGap(int gap) {
@@ -71,7 +71,7 @@ public class ExtraErrorStripePainter extends ErrorStripePainter {
   }
 
   @Override
-  public void paint(Graphics g, int x, int y, int width, int height) {
+  public void paint(Graphics2D g, int x, int y, int width, int height, Object object) {
     int min = getMinimalThickness();
     int gap = myGroupGap == null ? min : myGroupGap;
     int pos = x;
@@ -81,7 +81,7 @@ public class ExtraErrorStripePainter extends ErrorStripePainter {
     else {
       x += gap + min;
     }
-    myPainter.paint(g, pos, y, min, height);
-    super.paint(g, x, y, width - gap - min, height);
+    myPainter.paint(g, pos, y, min, height, object);
+    super.paint(g, x, y, width - gap - min, height, object);
   }
 }

platform/platform-impl/src/com/intellij/ui/stripe/TranslucencyThumbPainter.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.ui.stripe;
+
+import com.intellij.openapi.Disposable;
+import com.intellij.ui.Gray;
+import com.intellij.util.ui.JBUI;
+import com.intellij.util.ui.RegionPainter;
+import com.intellij.util.ui.UIUtil;
+
+import javax.swing.JScrollBar;
+import java.awt.*;
+
+/**
+ * @author Sergey.Malenkov
+ */
+final class TranslucencyThumbPainter implements Disposable, RegionPainter<Integer> {
+  private static final BasicStroke BASIC_STROKE = new BasicStroke();
+  private final ErrorStripePainter myPainter;
+  private final JScrollBar myScrollBar;
+
+  TranslucencyThumbPainter(ErrorStripePainter painter, JScrollBar bar) {
+    myPainter = painter;
+    myScrollBar = bar;
+    UIUtil.putClientProperty(myScrollBar, BUTTONLESS_SCROLL_BAR_UI_MAXI_THUMB, this);
+  }
+
+  @Override
+  public void dispose() {
+    UIUtil.putClientProperty(myScrollBar, BUTTONLESS_SCROLL_BAR_UI_MAXI_THUMB, null);
+  }
+
+  @Override
+  public void paint(Graphics2D g, int x, int y, int width, int height, Integer object) {
+    g = (Graphics2D)g.create(x, y, width, height);
+    g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
+    g.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_NORMALIZE);
+    g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, .5f));
+    g.setStroke(BASIC_STROKE);
+
+    boolean dark = UIUtil.isUnderDarcula();
+    int offset = object != null ? object + 11 : 11;
+    Color start = getColor(dark ? 95 + offset : 251 - offset);
+    Color stop = getColor(dark ? 80 + offset : 215 - offset);
+
+    Paint paint;
+    if (Adjustable.VERTICAL == myScrollBar.getOrientation()) {
+      x = 2;
+      y = 1;
+      width -= 3;
+      height -= 2;
+      if (myPainter instanceof ExtraErrorStripePainter) {
+        ExtraErrorStripePainter extra = (ExtraErrorStripePainter)myPainter;
+        int gap = extra.getMinimalThickness() - 1;
+        x += gap;
+        width -= gap;
+      }
+      paint = UIUtil.getGradientPaint(x, 0, start, x + width, 0, stop);
+    }
+    else {
+      x = 1;
+      y = 2;
+      width -= 2;
+      height -= 3;
+      paint = UIUtil.getGradientPaint(0, y, start, 0, y + height, stop);
+    }
+    int arc = JBUI.scale(3);
+    g.setPaint(paint);
+    g.fillRoundRect(x + 1, y + 1, width - 2, height - 2, arc, arc);
+    g.setColor(getColor(dark ? 85 : 201));
+    g.drawRoundRect(x, y, width - 1, height - 1, arc, arc);
+    g.dispose();
+  }
+
+  private static Color getColor(int gray) {
+    return Gray.get(gray < 0 ? 0 : gray > 255 ? 255 : gray);
+  }
+}

platform/platform-impl/src/com/intellij/ui/stripe/Updater.java

@@ -20,6 +20,7 @@ import com.intellij.openapi.Disposable;
 import com.intellij.openapi.actionSystem.CustomShortcutSet;
 import com.intellij.openapi.actionSystem.ShortcutSet;
 import com.intellij.openapi.keymap.KeymapManager;
+import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.util.registry.Registry;
 import com.intellij.util.ui.JBUI;
 import com.intellij.util.ui.RegionPainter;
@@ -31,7 +32,7 @@ import org.jetbrains.annotations.NotNull;
 import javax.swing.JScrollBar;
 import javax.swing.JScrollPane;
 import java.awt.Cursor;
-import java.awt.Graphics;
+import java.awt.Graphics2D;
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
 
@@ -60,15 +61,21 @@ public abstract class Updater<Painter extends ErrorStripePainter> implements Dis
     myScrollBar.addMouseListener(myMouseAdapter);
     myScrollBar.addMouseMotionListener(myMouseAdapter);
     myQueue = new MergingUpdateQueue("ErrorStripeUpdater", 100, true, myScrollBar, this);
-    UIUtil.putClientProperty(myScrollBar, RegionPainter.BUTTONLESS_SCROLL_BAR_UI_EXTRA_TRACK, new RegionPainter() {
+    UIUtil.putClientProperty(myScrollBar, RegionPainter.BUTTONLESS_SCROLL_BAR_UI_EXTRA_TRACK, new RegionPainter<Object>() {
       @Override
-      public void paint(Graphics g, int x, int y, int width, int height) {
+      public void paint(Graphics2D g, int x, int y, int width, int height, Object object) {
         DaemonCodeAnalyzerSettings settings = DaemonCodeAnalyzerSettings.getInstance();
         myPainter.setMinimalThickness(settings == null ? 2 : Math.min(settings.ERROR_STRIPE_MARK_MIN_HEIGHT, JBUI.scale(4)));
         myPainter.setErrorStripeGap(Registry.intValue("error.stripe.gap", 0));
-        myPainter.paint(g, x, y, width, height);
+        if (myPainter instanceof ExtraErrorStripePainter) {
+          ExtraErrorStripePainter extra = (ExtraErrorStripePainter)myPainter;
+          extra.setGroupSwap(!myScrollBar.getComponentOrientation().isLeftToRight());
+        }
+        myPainter.paint(g, x, y, width, height, object);
       }
     });
+    Disposer.register(this, new TranslucencyThumbPainter(myPainter, myScrollBar));
+    Disposer.register(this, new TranslucencyThumbPainter(null, pane.getHorizontalScrollBar()));
   }
 
   @Override
@@ -141,9 +148,7 @@ public abstract class Updater<Painter extends ErrorStripePainter> implements Dis
       @Override
       public void run() {
         update(myPainter);
-        if (myPainter.isModified()) {
-          myScrollBar.repaint();
-        }
+        myScrollBar.repaint();
       }
     });
   }

platform/util/resources/misc/registry.properties

@@ -606,7 +606,7 @@ editor.config.stop.at.project.root.description=Stops searching for .editorconfig
 editor.bold.underline.height=2
 editor.bold.underline.height.description=Underline height for EffectType.BOLD_LINE_UNDERSCORE
 
-error.stripe.enabled=false
+error.stripe.enabled=true
 error.stripe.gap=1
 error.stripe.gap.description=Minimal space between error stripe.