user/src/com/google/gwt/resources/rg/ImageResourceGenerator.java - gwt - Git at Google

 /*
  * Copyright 2008 Google Inc.
  *
  * 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.google.gwt.resources.rg;

 import com.google.gwt.core.ext.TreeLogger;
 import com.google.gwt.core.ext.UnableToCompleteException;
 import com.google.gwt.core.ext.typeinfo.JMethod;
 import com.google.gwt.core.ext.typeinfo.JType;
 import com.google.gwt.dev.util.Util;
 import com.google.gwt.resources.client.ImageResource.ImageOptions;
 import com.google.gwt.resources.client.ImageResource.RepeatStyle;
 import com.google.gwt.resources.client.impl.ImageResourcePrototype;
 import com.google.gwt.resources.ext.AbstractResourceGenerator;
 import com.google.gwt.resources.ext.ClientBundleFields;
 import com.google.gwt.resources.ext.ClientBundleRequirements;
 import com.google.gwt.resources.ext.ResourceContext;
 import com.google.gwt.resources.ext.ResourceGeneratorUtil;
 import com.google.gwt.resources.rg.ImageBundleBuilder.Arranger;
 import com.google.gwt.resources.rg.ImageBundleBuilder.ImageRect;
 import com.google.gwt.user.rebind.SourceWriter;
 import com.google.gwt.user.rebind.StringSourceWriter;

 import java.awt.geom.AffineTransform;
 import java.io.File;
 import java.io.IOException;
 import java.net.URL;
 import java.util.EnumMap;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.IdentityHashMap;
 import java.util.Map;
 import java.util.Set;

 /**
  * Builds an image strip for all ImageResources defined within an ClientBundle.
  */
 public final class ImageResourceGenerator extends AbstractResourceGenerator {
   /**
    * This is shared that can be shared across permutations for a given
    * ClientBundle type.
    */
   static class CachedState {
     /**
      * Associates an ImageRect with the ImageBundleBuilder that will emit its
      * bytes.
      */
     public final Map<ImageRect, ImageBundleBuilder> buildersByImageRect = new IdentityHashMap<ImageRect, ImageBundleBuilder>();

     /**
      * Associates a layout constraint with an ImageBundleBuilder that can
      * satisfy that constraint.
      */
     public final Map<RepeatStyle, ImageBundleBuilder> buildersByRepeatStyle = new EnumMap<RepeatStyle, ImageBundleBuilder>(
         RepeatStyle.class);

     /**
      * Associates a method name with the ImageRect that contains the data for
      * that method.
      */
     public final Map<String, ImageRect> imageRectsByName = new HashMap<String, ImageRect>();

     /**
      * Records that ImageRects that also need to provide an RTL-flipped version.
      */
     public final Set<ImageRect> rtlImages = new HashSet<ImageRect>();

     public final Map<ImageBundleBuilder, URL[]> urlsByBuilder = new IdentityHashMap<ImageBundleBuilder, URL[]>();

     /**
      * Maps an ImageRect to two URLs that contain the normal and flipped
      * contents.
      */
     public final Map<ImageRect, URL[]> urlsByExternalImageRect = new IdentityHashMap<ImageRect, URL[]>();
   }

   /**
    * This data is specific to a particular permutation.
    */
   static class LocalState {
     /**
      * Maps resource URLs to field names within the generated ClientBundle type.
      * These fields will be statically initialized to an expression that can be
      * used to access the contents of the resource URL.
      *
      * @see ImageResourceGenerator#maybeDeploy
      */
     public final Map<URL, String> fieldNamesByUrl = new HashMap<URL, String>();

     /**
      * Maps an ImageRect to a pair of Java expressions. The first can be used to
      * access the normal version of the resource, while the second, optional,
      * field is used to access an RTL-flipped version.
      */
     public final Map<ImageRect, String[]> urlExpressionsByImageRect = new HashMap<ImageRect, String[]>();
   }

   /**
    * This is set to <code>true</code> by {@link #init} if {@link #shared} was
    * initialized from cached data.
    */
   private boolean prepared;
   private CachedState shared;
   private LocalState local;
   private JType stringType;

   @Override
   public String createAssignment(TreeLogger logger, ResourceContext context,
       JMethod method) throws UnableToCompleteException {
     String name = method.getName();

     SourceWriter sw = new StringSourceWriter();
     sw.println("new " + ImageResourcePrototype.class.getName() + "(");
     sw.indent();
     sw.println('"' + name + "\",");

     ImageRect rect = shared.imageRectsByName.get(name);
     assert rect != null : "No ImageRect ever computed for " + name;

     String[] urlExpressions = local.urlExpressionsByImageRect.get(rect);
     assert urlExpressions != null : "No URL expression for " + name;
     assert urlExpressions.length == 2;

     if (urlExpressions[1] == null) {
       sw.println(urlExpressions[0] + ",");
     } else {
       sw.println("com.google.gwt.i18n.client.LocaleInfo.getCurrentLocale().isRTL() ?"
           + urlExpressions[1] + " : " + urlExpressions[0] + ",");
     }
     sw.println(rect.getLeft() + ", " + rect.getTop() + ", " + rect.getWidth()
         + ", " + rect.getHeight() + ", " + rect.isAnimated());

     sw.outdent();
     sw.print(")");

     return sw.toString();
   }

   /**
    * We use this as a signal that we have received all image methods and can now
    * create the bundled images.
    */
   @Override
   public void createFields(TreeLogger logger, ResourceContext context,
       ClientBundleFields fields) throws UnableToCompleteException {
     if (!prepared) {
       finalizeArrangements(logger, context);
     }

     for (ImageRect rect : shared.imageRectsByName.values()) {
       String[] urlExpressions;
       {
         URL[] contents;
         ImageBundleBuilder builder = shared.buildersByImageRect.get(rect);
         if (builder == null) {
           contents = shared.urlsByExternalImageRect.get(rect);
         } else {
           contents = shared.urlsByBuilder.get(builder);
         }
         assert contents != null && contents.length == 2;

         urlExpressions = new String[2];
         urlExpressions[0] = maybeDeploy(context, fields, contents[0]);
         urlExpressions[1] = maybeDeploy(context, fields, contents[1]);
       }
       local.urlExpressionsByImageRect.put(rect, urlExpressions);
     }
   }

   @Override
   public void finish(TreeLogger logger, ResourceContext context)
       throws UnableToCompleteException {
     local = null;
   }

   @Override
   public void init(TreeLogger logger, ResourceContext context) {
     // The images are bundled differently when data resources are supported
     String key = context.getClientBundleType().getQualifiedSourceName() + ":"
         + context.supportsDataUrls();
     shared = context.getCachedData(key, CachedState.class);
     prepared = shared != null;
     if (prepared) {
       logger.log(TreeLogger.DEBUG, "Using cached data");
     } else {
       shared = new CachedState();
       context.putCachedData(key, shared);
     }
     local = new LocalState();

     stringType = context.getGeneratorContext().getTypeOracle().findType(
         String.class.getCanonicalName());
     assert stringType != null : "No String type";
   }

   /**
    * Process each image method. This will either assign the image to an
    * ImageBundleBuilder or reencode an external image.
    */
   @Override
   public void prepare(TreeLogger logger, ResourceContext context,
       ClientBundleRequirements requirements, JMethod method)
       throws UnableToCompleteException {
     if (prepared) {
       return;
     }

     URL[] resources = ResourceGeneratorUtil.findResources(logger, context,
         method);

     if (resources.length != 1) {
       logger.log(TreeLogger.ERROR, "Exactly one image may be specified", null);
       throw new UnableToCompleteException();
     }

     ImageBundleBuilder builder = getBuilder(method);
     URL resource = resources[0];
     String name = method.getName();

     ImageRect rect;
     try {
       rect = builder.assimilate(logger, name, resource);
       if (context.supportsDataUrls()
           || getRepeatStyle(method) == RepeatStyle.Both) {
         // Just use the calculated meta-data
         builder.removeMapping(name);
         rect.setPosition(0, 0);
         throw new UnsuitableForStripException(rect);
       }
       shared.buildersByImageRect.put(rect, builder);
     } catch (UnsuitableForStripException e) {
       // Add the image to the output as a separate resource
       URL normalContents;
       rect = e.getImageRect();

       if (rect.isAnimated()) {
         // Can't re-encode animated images, so we emit it as-is
         normalContents = resource;
       } else {
         normalContents = reencodeToTempFile(logger, rect);
       }
       shared.urlsByExternalImageRect.put(rect, new URL[] {normalContents, null});
     }

     shared.imageRectsByName.put(name, rect);

     if (getFlipRtl(method)) {
       shared.rtlImages.add(rect);
     }
   }

   private void finalizeArrangements(TreeLogger logger, ResourceContext context)
       throws UnableToCompleteException {
     for (Map.Entry<RepeatStyle, ImageBundleBuilder> entry : shared.buildersByRepeatStyle.entrySet()) {
       RepeatStyle repeatStyle = entry.getKey();
       ImageBundleBuilder builder = entry.getValue();
       Arranger arranger;

       switch (repeatStyle) {
         case None:
           arranger = new ImageBundleBuilder.BestFitArranger();
           break;
         case Horizontal:
           arranger = new ImageBundleBuilder.VerticalArranger();
           break;
         case Vertical:
           arranger = new ImageBundleBuilder.HorizontalArranger();
           break;
         case Both:
           // This is taken care of when writing the external images;
           continue;
         default:
           logger.log(TreeLogger.ERROR, "Unknown RepeatStyle" + repeatStyle);
           throw new UnableToCompleteException();
       }
       URL normalContents = renderToTempFile(logger, builder, arranger);

       shared.urlsByBuilder.put(builder, new URL[] {normalContents, null});
     }

     if (shared.rtlImages.size() > 0) {
       Set<ImageBundleBuilder> rtlBuilders = new HashSet<ImageBundleBuilder>();

       for (ImageRect rtlImage : shared.rtlImages) {
         // Create a transformation to mirror about the Y-axis and translate
         AffineTransform tx = new AffineTransform();
         tx.setTransform(-1, 0, 0, 1, rtlImage.getWidth(), 0);
         rtlImage.setTransform(tx);

         if (shared.buildersByImageRect.containsKey(rtlImage)) {
           /*
            * This image is assigned to a builder, so we'll just remember to
            * regenerate that builder.
            */
           rtlBuilders.add(shared.buildersByImageRect.get(rtlImage));
         } else {
           // Otherwise, emit the external version
           URL[] contents = shared.urlsByExternalImageRect.get(rtlImage);
           assert contents != null;
           contents[1] = reencodeToTempFile(logger, rtlImage);
         }
       }

       for (ImageBundleBuilder builder : rtlBuilders) {
         URL[] contents = shared.urlsByBuilder.get(builder);
         assert contents != null && contents.length == 2;

         contents[1] = renderToTempFile(logger, builder,
             new ImageBundleBuilder.IdentityArranger());
       }
     }
   }

   private ImageBundleBuilder getBuilder(JMethod method) {
     RepeatStyle repeatStyle = getRepeatStyle(method);
     ImageBundleBuilder builder = shared.buildersByRepeatStyle.get(repeatStyle);
     if (builder == null) {
       builder = new ImageBundleBuilder();
       shared.buildersByRepeatStyle.put(repeatStyle, builder);
     }
     return builder;
   }

   private boolean getFlipRtl(JMethod method) {
     ImageOptions options = method.getAnnotation(ImageOptions.class);
     if (options == null) {
       return false;
     } else {
       return options.flipRtl();
     }
   }

   private RepeatStyle getRepeatStyle(JMethod method) {
     ImageOptions options = method.getAnnotation(ImageOptions.class);
     if (options == null) {
       return RepeatStyle.None;
     } else {
       return options.repeatStyle();
     }
   }

   /**
    * Create a field in the ClientBundle type that is used to intern the URL
    * expressions that can be used to access the contents of the given resource.
    *
    * @return the name of the field that was created
    */
   private String maybeDeploy(ResourceContext context,
       ClientBundleFields fields, URL resource) throws UnableToCompleteException {
     if (resource == null) {
       return null;
     }

     String toReturn = local.fieldNamesByUrl.get(resource);
     if (toReturn == null) {
       String urlExpression = context.deploy(resource, false);
       toReturn = fields.define(stringType, "internedUrl"
           + local.fieldNamesByUrl.size(), urlExpression, true, true);
       local.fieldNamesByUrl.put(resource, toReturn);
     }
     return toReturn;
   }

   /**
    * Re-encode an image as a PNG to strip random header data.
    */
   private URL reencodeToTempFile(TreeLogger logger, ImageRect rect)
       throws UnableToCompleteException {
     try {
       byte[] imageBytes = ImageBundleBuilder.toPng(logger, rect);

       if (imageBytes == null) {
         return null;
       }

       File file = File.createTempFile(
           ImageResourceGenerator.class.getSimpleName(), ".png");
       file.deleteOnExit();
       Util.writeBytesToFile(logger, file, imageBytes);
       return file.toURI().toURL();
     } catch (IOException ex) {
       logger.log(TreeLogger.ERROR, "Unable to write re-encoded PNG", ex);
       throw new UnableToCompleteException();
     }
   }

   /**
    * Re-encode an image as a PNG to strip random header data.
    */
   private URL renderToTempFile(TreeLogger logger, ImageBundleBuilder builder,
       Arranger arranger) throws UnableToCompleteException {
     try {
       byte[] imageBytes = builder.render(logger, arranger);
       if (imageBytes == null) {
         return null;
       }

       File file = File.createTempFile(
           ImageResourceGenerator.class.getSimpleName(), ".png");
       file.deleteOnExit();
       Util.writeBytesToFile(logger, file, imageBytes);
       return file.toURI().toURL();
     } catch (IOException ex) {
       logger.log(TreeLogger.ERROR, "Unable to write re-encoded PNG", ex);
       throw new UnableToCompleteException();
     }
   }
 }
	/*
	* Copyright 2008 Google Inc.
	*
	* 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.google.gwt.resources.rg;

	import com.google.gwt.core.ext.TreeLogger;
	import com.google.gwt.core.ext.UnableToCompleteException;
	import com.google.gwt.core.ext.typeinfo.JMethod;
	import com.google.gwt.core.ext.typeinfo.JType;
	import com.google.gwt.dev.util.Util;
	import com.google.gwt.resources.client.ImageResource.ImageOptions;
	import com.google.gwt.resources.client.ImageResource.RepeatStyle;
	import com.google.gwt.resources.client.impl.ImageResourcePrototype;
	import com.google.gwt.resources.ext.AbstractResourceGenerator;
	import com.google.gwt.resources.ext.ClientBundleFields;
	import com.google.gwt.resources.ext.ClientBundleRequirements;
	import com.google.gwt.resources.ext.ResourceContext;
	import com.google.gwt.resources.ext.ResourceGeneratorUtil;
	import com.google.gwt.resources.rg.ImageBundleBuilder.Arranger;
	import com.google.gwt.resources.rg.ImageBundleBuilder.ImageRect;
	import com.google.gwt.user.rebind.SourceWriter;
	import com.google.gwt.user.rebind.StringSourceWriter;

	import java.awt.geom.AffineTransform;
	import java.io.File;
	import java.io.IOException;
	import java.net.URL;
	import java.util.EnumMap;
	import java.util.HashMap;
	import java.util.HashSet;
	import java.util.IdentityHashMap;
	import java.util.Map;
	import java.util.Set;

	/**
	* Builds an image strip for all ImageResources defined within an ClientBundle.
	*/
	public final class ImageResourceGenerator extends AbstractResourceGenerator {
	/**
	* This is shared that can be shared across permutations for a given
	* ClientBundle type.
	*/
	static class CachedState {
	/**
	* Associates an ImageRect with the ImageBundleBuilder that will emit its
	* bytes.
	*/
	public final Map<ImageRect, ImageBundleBuilder> buildersByImageRect = new IdentityHashMap<ImageRect, ImageBundleBuilder>();

	/**
	* Associates a layout constraint with an ImageBundleBuilder that can
	* satisfy that constraint.
	*/
	public final Map<RepeatStyle, ImageBundleBuilder> buildersByRepeatStyle = new EnumMap<RepeatStyle, ImageBundleBuilder>(
	RepeatStyle.class);

	/**
	* Associates a method name with the ImageRect that contains the data for
	* that method.
	*/
	public final Map<String, ImageRect> imageRectsByName = new HashMap<String, ImageRect>();

	/**
	* Records that ImageRects that also need to provide an RTL-flipped version.
	*/
	public final Set<ImageRect> rtlImages = new HashSet<ImageRect>();

	public final Map<ImageBundleBuilder, URL[]> urlsByBuilder = new IdentityHashMap<ImageBundleBuilder, URL[]>();

	/**
	* Maps an ImageRect to two URLs that contain the normal and flipped
	* contents.
	*/
	public final Map<ImageRect, URL[]> urlsByExternalImageRect = new IdentityHashMap<ImageRect, URL[]>();
	}

	/**
	* This data is specific to a particular permutation.
	*/
	static class LocalState {
	/**
	* Maps resource URLs to field names within the generated ClientBundle type.
	* These fields will be statically initialized to an expression that can be
	* used to access the contents of the resource URL.
	*
	* @see ImageResourceGenerator#maybeDeploy
	*/
	public final Map<URL, String> fieldNamesByUrl = new HashMap<URL, String>();

	/**
	* Maps an ImageRect to a pair of Java expressions. The first can be used to
	* access the normal version of the resource, while the second, optional,
	* field is used to access an RTL-flipped version.
	*/
	public final Map<ImageRect, String[]> urlExpressionsByImageRect = new HashMap<ImageRect, String[]>();
	}

	/**
	* This is set to <code>true</code> by {@link #init} if {@link #shared} was
	* initialized from cached data.
	*/
	private boolean prepared;
	private CachedState shared;
	private LocalState local;
	private JType stringType;

	@Override
	public String createAssignment(TreeLogger logger, ResourceContext context,
	JMethod method) throws UnableToCompleteException {
	String name = method.getName();

	SourceWriter sw = new StringSourceWriter();
	sw.println("new " + ImageResourcePrototype.class.getName() + "(");
	sw.indent();
	sw.println('"' + name + "\",");

	ImageRect rect = shared.imageRectsByName.get(name);
	assert rect != null : "No ImageRect ever computed for " + name;

	String[] urlExpressions = local.urlExpressionsByImageRect.get(rect);
	assert urlExpressions != null : "No URL expression for " + name;
	assert urlExpressions.length == 2;

	if (urlExpressions[1] == null) {
	sw.println(urlExpressions[0] + ",");
	} else {
	sw.println("com.google.gwt.i18n.client.LocaleInfo.getCurrentLocale().isRTL() ?"
	+ urlExpressions[1] + " : " + urlExpressions[0] + ",");
	}
	sw.println(rect.getLeft() + ", " + rect.getTop() + ", " + rect.getWidth()
	+ ", " + rect.getHeight() + ", " + rect.isAnimated());

	sw.outdent();
	sw.print(")");

	return sw.toString();
	}

	/**
	* We use this as a signal that we have received all image methods and can now
	* create the bundled images.
	*/
	@Override
	public void createFields(TreeLogger logger, ResourceContext context,
	ClientBundleFields fields) throws UnableToCompleteException {
	if (!prepared) {
	finalizeArrangements(logger, context);
	}

	for (ImageRect rect : shared.imageRectsByName.values()) {
	String[] urlExpressions;
	{
	URL[] contents;
	ImageBundleBuilder builder = shared.buildersByImageRect.get(rect);
	if (builder == null) {
	contents = shared.urlsByExternalImageRect.get(rect);
	} else {
	contents = shared.urlsByBuilder.get(builder);
	}
	assert contents != null && contents.length == 2;

	urlExpressions = new String[2];
	urlExpressions[0] = maybeDeploy(context, fields, contents[0]);
	urlExpressions[1] = maybeDeploy(context, fields, contents[1]);
	}
	local.urlExpressionsByImageRect.put(rect, urlExpressions);
	}
	}

	@Override
	public void finish(TreeLogger logger, ResourceContext context)
	throws UnableToCompleteException {
	local = null;
	}

	@Override
	public void init(TreeLogger logger, ResourceContext context) {
	// The images are bundled differently when data resources are supported
	String key = context.getClientBundleType().getQualifiedSourceName() + ":"
	+ context.supportsDataUrls();
	shared = context.getCachedData(key, CachedState.class);
	prepared = shared != null;
	if (prepared) {
	logger.log(TreeLogger.DEBUG, "Using cached data");
	} else {
	shared = new CachedState();
	context.putCachedData(key, shared);
	}
	local = new LocalState();

	stringType = context.getGeneratorContext().getTypeOracle().findType(
	String.class.getCanonicalName());
	assert stringType != null : "No String type";
	}

	/**
	* Process each image method. This will either assign the image to an
	* ImageBundleBuilder or reencode an external image.
	*/
	@Override
	public void prepare(TreeLogger logger, ResourceContext context,
	ClientBundleRequirements requirements, JMethod method)
	throws UnableToCompleteException {
	if (prepared) {
	return;
	}

	URL[] resources = ResourceGeneratorUtil.findResources(logger, context,
	method);

	if (resources.length != 1) {
	logger.log(TreeLogger.ERROR, "Exactly one image may be specified", null);
	throw new UnableToCompleteException();
	}

	ImageBundleBuilder builder = getBuilder(method);
	URL resource = resources[0];
	String name = method.getName();

	ImageRect rect;
	try {
	rect = builder.assimilate(logger, name, resource);
	if (context.supportsDataUrls()
	\|\| getRepeatStyle(method) == RepeatStyle.Both) {
	// Just use the calculated meta-data
	builder.removeMapping(name);
	rect.setPosition(0, 0);
	throw new UnsuitableForStripException(rect);
	}
	shared.buildersByImageRect.put(rect, builder);
	} catch (UnsuitableForStripException e) {
	// Add the image to the output as a separate resource
	URL normalContents;
	rect = e.getImageRect();

	if (rect.isAnimated()) {
	// Can't re-encode animated images, so we emit it as-is
	normalContents = resource;
	} else {
	normalContents = reencodeToTempFile(logger, rect);
	}
	shared.urlsByExternalImageRect.put(rect, new URL[] {normalContents, null});
	}

	shared.imageRectsByName.put(name, rect);

	if (getFlipRtl(method)) {
	shared.rtlImages.add(rect);
	}
	}

	private void finalizeArrangements(TreeLogger logger, ResourceContext context)
	throws UnableToCompleteException {
	for (Map.Entry<RepeatStyle, ImageBundleBuilder> entry : shared.buildersByRepeatStyle.entrySet()) {
	RepeatStyle repeatStyle = entry.getKey();
	ImageBundleBuilder builder = entry.getValue();
	Arranger arranger;

	switch (repeatStyle) {
	case None:
	arranger = new ImageBundleBuilder.BestFitArranger();
	break;
	case Horizontal:
	arranger = new ImageBundleBuilder.VerticalArranger();
	break;
	case Vertical:
	arranger = new ImageBundleBuilder.HorizontalArranger();
	break;
	case Both:
	// This is taken care of when writing the external images;
	continue;
	default:
	logger.log(TreeLogger.ERROR, "Unknown RepeatStyle" + repeatStyle);
	throw new UnableToCompleteException();
	}
	URL normalContents = renderToTempFile(logger, builder, arranger);

	shared.urlsByBuilder.put(builder, new URL[] {normalContents, null});
	}

	if (shared.rtlImages.size() > 0) {
	Set<ImageBundleBuilder> rtlBuilders = new HashSet<ImageBundleBuilder>();

	for (ImageRect rtlImage : shared.rtlImages) {
	// Create a transformation to mirror about the Y-axis and translate
	AffineTransform tx = new AffineTransform();
	tx.setTransform(-1, 0, 0, 1, rtlImage.getWidth(), 0);
	rtlImage.setTransform(tx);

	if (shared.buildersByImageRect.containsKey(rtlImage)) {
	/*
	* This image is assigned to a builder, so we'll just remember to
	* regenerate that builder.
	*/
	rtlBuilders.add(shared.buildersByImageRect.get(rtlImage));
	} else {
	// Otherwise, emit the external version
	URL[] contents = shared.urlsByExternalImageRect.get(rtlImage);
	assert contents != null;
	contents[1] = reencodeToTempFile(logger, rtlImage);
	}
	}

	for (ImageBundleBuilder builder : rtlBuilders) {
	URL[] contents = shared.urlsByBuilder.get(builder);
	assert contents != null && contents.length == 2;

	contents[1] = renderToTempFile(logger, builder,
	new ImageBundleBuilder.IdentityArranger());
	}
	}
	}

	private ImageBundleBuilder getBuilder(JMethod method) {
	RepeatStyle repeatStyle = getRepeatStyle(method);
	ImageBundleBuilder builder = shared.buildersByRepeatStyle.get(repeatStyle);
	if (builder == null) {
	builder = new ImageBundleBuilder();
	shared.buildersByRepeatStyle.put(repeatStyle, builder);
	}
	return builder;
	}

	private boolean getFlipRtl(JMethod method) {
	ImageOptions options = method.getAnnotation(ImageOptions.class);
	if (options == null) {
	return false;
	} else {
	return options.flipRtl();
	}
	}

	private RepeatStyle getRepeatStyle(JMethod method) {
	ImageOptions options = method.getAnnotation(ImageOptions.class);
	if (options == null) {
	return RepeatStyle.None;
	} else {
	return options.repeatStyle();
	}
	}

	/**
	* Create a field in the ClientBundle type that is used to intern the URL
	* expressions that can be used to access the contents of the given resource.
	*
	* @return the name of the field that was created
	*/
	private String maybeDeploy(ResourceContext context,
	ClientBundleFields fields, URL resource) throws UnableToCompleteException {
	if (resource == null) {
	return null;
	}

	String toReturn = local.fieldNamesByUrl.get(resource);
	if (toReturn == null) {
	String urlExpression = context.deploy(resource, false);
	toReturn = fields.define(stringType, "internedUrl"
	+ local.fieldNamesByUrl.size(), urlExpression, true, true);
	local.fieldNamesByUrl.put(resource, toReturn);
	}
	return toReturn;
	}

	/**
	* Re-encode an image as a PNG to strip random header data.
	*/
	private URL reencodeToTempFile(TreeLogger logger, ImageRect rect)
	throws UnableToCompleteException {
	try {
	byte[] imageBytes = ImageBundleBuilder.toPng(logger, rect);

	if (imageBytes == null) {
	return null;
	}

	File file = File.createTempFile(
	ImageResourceGenerator.class.getSimpleName(), ".png");
	file.deleteOnExit();
	Util.writeBytesToFile(logger, file, imageBytes);
	return file.toURI().toURL();
	} catch (IOException ex) {
	logger.log(TreeLogger.ERROR, "Unable to write re-encoded PNG", ex);
	throw new UnableToCompleteException();
	}
	}

	/**
	* Re-encode an image as a PNG to strip random header data.
	*/
	private URL renderToTempFile(TreeLogger logger, ImageBundleBuilder builder,
	Arranger arranger) throws UnableToCompleteException {
	try {
	byte[] imageBytes = builder.render(logger, arranger);
	if (imageBytes == null) {
	return null;
	}

	File file = File.createTempFile(
	ImageResourceGenerator.class.getSimpleName(), ".png");
	file.deleteOnExit();
	Util.writeBytesToFile(logger, file, imageBytes);
	return file.toURI().toURL();
	} catch (IOException ex) {
	logger.log(TreeLogger.ERROR, "Unable to write re-encoded PNG", ex);
	throw new UnableToCompleteException();
	}
	}
	}