Dave Jarvis' Repositories

git clone https://repo.autonoma.ca/repo/keenwrite.git
keenwrite / Commits / 784f5c2

Migrate SVG-related code into preview package

AuthorDaveJarvis <email>
Date2020-09-13 14:41:08 GMT-0700
Commit784f5c2ac925d380572817460f97b4bc42a0ab95
Parenta1f4bbc
Delta547 lines added, 3 lines removed, 544-line increase
src/test/java/com/scrivenvar/tex/TeXRasterization.java
import java.nio.file.Path;
-import static com.scrivenvar.graphics.SvgRasterizer.rasterizeString;
-import static com.scrivenvar.graphics.SvgRasterizer.toSvg;
+import static com.scrivenvar.preview.SvgRasterizer.rasterizeString;
+import static com.scrivenvar.preview.SvgRasterizer.toSvg;
import static java.lang.System.getProperty;
import static org.junit.jupiter.api.Assertions.assertEquals;
src/main/java/com/scrivenvar/preview/HTMLPreviewPane.java
import com.scrivenvar.adapters.DocumentAdapter;
-import com.scrivenvar.graphics.SvgReplacedElementFactory;
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.SimpleBooleanProperty;
src/main/java/com/scrivenvar/preview/RenderingSettings.java
+/*
+ * Copyright 2020 White Magic Software, Ltd.
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * o Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * o Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.scrivenvar.preview;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static java.awt.RenderingHints.*;
+import static java.awt.Toolkit.getDefaultToolkit;
+
+/**
+ * Responsible for supplying consistent rendering hints throughout the
+ * application, such as image rendering for {@link SvgRasterizer}.
+ */
+@SuppressWarnings("rawtypes")
+public class RenderingSettings {
+
+ /**
+ * Default hints for high-quality rendering that may be changed by
+ * the system's rendering hints.
+ */
+ private static final Map<Object, Object> DEFAULT_HINTS = Map.of(
+ KEY_ANTIALIASING,
+ VALUE_ANTIALIAS_ON,
+ KEY_ALPHA_INTERPOLATION,
+ VALUE_ALPHA_INTERPOLATION_QUALITY,
+ KEY_COLOR_RENDERING,
+ VALUE_COLOR_RENDER_QUALITY,
+ KEY_DITHERING,
+ VALUE_DITHER_DISABLE,
+ KEY_FRACTIONALMETRICS,
+ VALUE_FRACTIONALMETRICS_ON,
+ KEY_INTERPOLATION,
+ VALUE_INTERPOLATION_BICUBIC,
+ KEY_RENDERING,
+ VALUE_RENDER_QUALITY,
+ KEY_STROKE_CONTROL,
+ VALUE_STROKE_PURE,
+ KEY_TEXT_ANTIALIASING,
+ VALUE_TEXT_ANTIALIAS_ON
+ );
+
+ /**
+ * Shared hints for high-quality rendering.
+ */
+ public static final Map<Object, Object> RENDERING_HINTS = new HashMap<>(
+ DEFAULT_HINTS
+ );
+
+ static {
+ final var toolkit = getDefaultToolkit();
+ final var hints = toolkit.getDesktopProperty( "awt.font.desktophints" );
+
+ if( hints instanceof Map ) {
+ final var map = (Map) hints;
+ for( final var key : map.keySet() ) {
+ final var hint = map.get( key );
+ RENDERING_HINTS.put( key, hint );
+ }
+ }
+ }
+
+ /**
+ * Prevent instantiation as per Joshua Bloch's recommendation.
+ */
+ private RenderingSettings() {
+ }
+}
src/main/java/com/scrivenvar/preview/SvgRasterizer.java
+/*
+ * Copyright 2020 White Magic Software, Ltd.
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * o Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * o Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.scrivenvar.preview;
+
+import org.apache.batik.anim.dom.SAXSVGDocumentFactory;
+import org.apache.batik.gvt.renderer.ImageRenderer;
+import org.apache.batik.transcoder.TranscoderException;
+import org.apache.batik.transcoder.TranscoderInput;
+import org.apache.batik.transcoder.TranscoderOutput;
+import org.apache.batik.transcoder.image.ImageTranscoder;
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+
+import javax.xml.transform.Transformer;
+import javax.xml.transform.TransformerConfigurationException;
+import javax.xml.transform.TransformerFactory;
+import javax.xml.transform.dom.DOMSource;
+import javax.xml.transform.stream.StreamResult;
+import java.awt.*;
+import java.awt.image.BufferedImage;
+import java.io.IOException;
+import java.io.StringReader;
+import java.io.StringWriter;
+import java.net.URL;
+import java.text.NumberFormat;
+
+import static com.scrivenvar.StatusBarNotifier.alert;
+import static com.scrivenvar.preview.RenderingSettings.RENDERING_HINTS;
+import static java.awt.image.BufferedImage.TYPE_INT_RGB;
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.text.NumberFormat.getIntegerInstance;
+import static javax.xml.transform.OutputKeys.*;
+import static org.apache.batik.transcoder.SVGAbstractTranscoder.KEY_WIDTH;
+import static org.apache.batik.util.XMLResourceDescriptor.getXMLParserClassName;
+
+/**
+ * Responsible for converting SVG images into rasterized PNG images.
+ */
+public class SvgRasterizer {
+ private static final SAXSVGDocumentFactory FACTORY_DOM =
+ new SAXSVGDocumentFactory( getXMLParserClassName() );
+
+ private static final TransformerFactory FACTORY_TRANSFORM =
+ TransformerFactory.newInstance();
+
+ private static final Transformer sTransformer;
+
+ static {
+ Transformer t;
+
+ try {
+ t = FACTORY_TRANSFORM.newTransformer();
+ t.setOutputProperty( OMIT_XML_DECLARATION, "yes" );
+ t.setOutputProperty( METHOD, "xml" );
+ t.setOutputProperty( INDENT, "no" );
+ t.setOutputProperty( ENCODING, UTF_8.name() );
+ } catch( final TransformerConfigurationException e ) {
+ t = null;
+ }
+
+ sTransformer = t;
+ }
+
+ private static final NumberFormat INT_FORMAT = getIntegerInstance();
+
+ public static final BufferedImage BROKEN_IMAGE_PLACEHOLDER;
+
+ /**
+ * A FontAwesome camera icon, cleft asunder.
+ */
+ public static final String BROKEN_IMAGE_SVG =
+ "<svg height='19pt' viewBox='0 0 25 19' " +
+ "width='25pt' xmlns='http://www.w3.org/2000/svg'><g " +
+ "fill='#454545'><path d='m8.042969 11.085938c.332031 1.445312 1" +
+ ".660156 2.503906 3.214843 2.558593zm0 0'/><path d='m6.792969 9" +
+ ".621094-.300781.226562.242187.195313c.015625-.144531.03125-.28125" +
+ ".058594-.421875zm0 0'/><path d='m10.597656.949219-2.511718" +
+ ".207031c-" +
+ ".777344.066406-1.429688.582031-1.636719 1.292969l-.367188 1" +
+ ".253906-3" +
+ ".414062.28125c-1.027344.085937-1.792969.949219-1.699219 1.925781l" +
+ ".976562 10.621094c.089844.976562.996094 1.699219 2.023438 1" +
+ ".613281l11.710938-.972656-3.117188-2.484375c-.246094.0625-.5" +
+ ".109375-" +
+ ".765625.132812-2.566406.210938-4.835937-1.597656-5.0625-4.039062-" +
+ ".023437-.25-.019531-.496094 0-.738281l-.242187-.195313.300781-" +
+ ".226562c.359375-1.929688 2.039062-3.472656 4.191406-3.652344" +
+ ".207031-" +
+ ".015625.414063-.015625.617187-.007812l.933594-.707032zm0 0'/><path" +
+ " " +
+ "d='m10.234375 11.070312 2.964844 2.820313c.144531.015625.285156" +
+ ".027344.433593.027344 1.890626 0 3.429688-1.460938 3.429688-3" +
+ ".257813" +
+ " 0-1.792968-1.539062-3.257812-3.429688-3.257812-1.890624 0-3" +
+ ".429687 " +
+ "1.464844-3.429687 3.257812 0 .140625.011719.277344.03125.410156zm0" +
+ " " +
+ "0'/><path d='m14.488281.808594 1.117188 4.554687-1.042969.546875c2" +
+ ".25.476563 3.84375 2.472656 3.636719 4.714844-.199219 2.191406-2" +
+ ".050781 3.871094-4.285157 4.039062l2.609376 2.957032 4.4375" +
+ ".371094c1" +
+ ".03125.085937 1.9375-.640626 2.027343-1.617188l.976563-10.617188c" +
+ ".089844-.980468-.667969-1.839843-1.699219-1.925781l-3.414063-" +
+ ".285156-.371093-1.253906c-.207031-.710938-.859375-1.226563-1" +
+ ".636719-1.289063zm0 0'/></g></svg>";
+
+ static {
+ // The width and height cannot be embedded in the SVG above because the
+ // path element values are relative to the viewBox dimensions.
+ final int w = 75;
+ final int h = 75;
+ BufferedImage image;
+
+ try {
+ image = rasterizeString( BROKEN_IMAGE_SVG, w );
+ } catch( final Exception e ) {
+ image = new BufferedImage( w, h, TYPE_INT_RGB );
+ final var graphics = (Graphics2D) image.getGraphics();
+ graphics.setRenderingHints( RENDERING_HINTS );
+
+ // Fall back to a (\) symbol.
+ graphics.setColor( new Color( 204, 204, 204 ) );
+ graphics.fillRect( 0, 0, w, h );
+ graphics.setColor( new Color( 255, 204, 204 ) );
+ graphics.setStroke( new BasicStroke( 4 ) );
+ graphics.drawOval( w / 4, h / 4, w / 2, h / 2 );
+ graphics.drawLine( w / 4 + (int) (w / 4 / Math.PI),
+ h / 4 + (int) (w / 4 / Math.PI),
+ w / 2 + w / 4 - (int) (w / 4 / Math.PI),
+ h / 2 + h / 4 - (int) (w / 4 / Math.PI) );
+ }
+
+ BROKEN_IMAGE_PLACEHOLDER = image;
+ }
+
+ private static class BufferedImageTranscoder extends ImageTranscoder {
+ private BufferedImage mImage;
+
+ @Override
+ public BufferedImage createImage( final int w, final int h ) {
+ return new BufferedImage( w, h, BufferedImage.TYPE_INT_ARGB );
+ }
+
+ @Override
+ public void writeImage(
+ final BufferedImage image, final TranscoderOutput output ) {
+ mImage = image;
+ }
+
+ public BufferedImage getImage() {
+ return mImage;
+ }
+
+ @Override
+ protected ImageRenderer createRenderer() {
+ final ImageRenderer renderer = super.createRenderer();
+ final RenderingHints hints = renderer.getRenderingHints();
+ hints.putAll( RENDERING_HINTS );
+
+ renderer.setRenderingHints( hints );
+
+ return renderer;
+ }
+ }
+
+ /**
+ * Rasterizes the vector graphic file at the given URL. If any exception
+ * happens, a red circle is returned instead.
+ *
+ * @param url The URL to a vector graphic file, which must include the
+ * protocol scheme (such as file:// or https://).
+ * @param width The number of pixels wide to render the image. The aspect
+ * ratio is maintained.
+ * @return Either the rasterized image upon success or a red circle.
+ */
+ public static BufferedImage rasterize( final String url, final int width ) {
+ try {
+ return rasterize( new URL( url ), width );
+ } catch( final Exception e ) {
+ alert( e );
+ return BROKEN_IMAGE_PLACEHOLDER;
+ }
+ }
+
+ /**
+ * Converts an SVG drawing into a rasterized image that can be drawn on
+ * a graphics context.
+ *
+ * @param url The path to the image (can be web address).
+ * @param width Scale the image width to this size (aspect ratio is
+ * maintained).
+ * @return The vector graphic transcoded into a raster image format.
+ * @throws IOException Could not read the vector graphic.
+ * @throws TranscoderException Could not convert the vector graphic to an
+ * instance of {@link Image}.
+ */
+ public static BufferedImage rasterize( final URL url, final int width )
+ throws IOException, TranscoderException {
+ return rasterize( FACTORY_DOM.createDocument( url.toString() ), width );
+ }
+
+ /**
+ * Converts an SVG string into a rasterized image that can be drawn on
+ * a graphics context.
+ *
+ * @param svg The SVG xml document.
+ * @param w Scale the image width to this size (aspect ratio is
+ * maintained).
+ * @return The vector graphic transcoded into a raster image format.
+ * @throws TranscoderException Could not convert the vector graphic to an
+ * instance of {@link Image}.
+ */
+ public static BufferedImage rasterizeString( final String svg, final int w )
+ throws IOException, TranscoderException {
+ return rasterize( toDocument( svg ), w );
+ }
+
+ /**
+ * Converts an SVG string into a rasterized image that can be drawn on
+ * a graphics context. The dimensions are determined from the document.
+ *
+ * @param xml The SVG xml document.
+ * @return The vector graphic transcoded into a raster image format.
+ */
+ public static BufferedImage rasterizeString( final String xml ) {
+ try {
+ final var doc = toDocument( xml );
+ final var root = doc.getDocumentElement();
+ final var width = root.getAttribute( "width" );
+ return rasterizeString( xml, INT_FORMAT.parse( width ).intValue() );
+ } catch( final Exception e ) {
+ alert( e );
+ return BROKEN_IMAGE_PLACEHOLDER;
+ }
+ }
+
+ /**
+ * Converts an SVG XML string into a new {@link Document} instance.
+ *
+ * @param xml The XML containing SVG elements.
+ * @return The SVG contents parsed into a {@link Document} object model.
+ * @throws IOException Could
+ */
+ private static Document toDocument( final String xml ) throws IOException {
+ try( final var reader = new StringReader( xml ) ) {
+ return FACTORY_DOM.createSVGDocument(
+ "http://www.w3.org/2000/svg", reader );
+ }
+ }
+
+ public static BufferedImage rasterize( final Document svg, final int width )
+ throws TranscoderException {
+ final var transcoder = new BufferedImageTranscoder();
+ final var input = new TranscoderInput( svg );
+
+ transcoder.addTranscodingHint( KEY_WIDTH, (float) width );
+ transcoder.transcode( input, null );
+
+ return transcoder.getImage();
+ }
+
+ /**
+ * Given a document object model (DOM) {@link Element}, this will convert that
+ * element to a string.
+ *
+ * @param e The DOM node to convert to a string.
+ * @return The DOM node as an escaped, plain text string.
+ */
+ public static String toSvg( final Element e ) {
+ try( final var writer = new StringWriter() ) {
+ sTransformer.transform( new DOMSource( e ), new StreamResult( writer ) );
+ return writer.toString().replaceAll( "xmlns=\"\" ", "" );
+ } catch( final Exception ex ) {
+ alert( ex );
+ }
+
+ return BROKEN_IMAGE_SVG;
+ }
+}
src/main/java/com/scrivenvar/preview/SvgReplacedElementFactory.java
+/*
+ * Copyright 2020 White Magic Software, Ltd.
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * o Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * o Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.scrivenvar.preview;
+
+import com.scrivenvar.util.BoundedCache;
+import org.apache.commons.io.FilenameUtils;
+import org.w3c.dom.Element;
+import org.xhtmlrenderer.extend.ReplacedElement;
+import org.xhtmlrenderer.extend.ReplacedElementFactory;
+import org.xhtmlrenderer.extend.UserAgentCallback;
+import org.xhtmlrenderer.layout.LayoutContext;
+import org.xhtmlrenderer.render.BlockBox;
+import org.xhtmlrenderer.simple.extend.FormSubmissionListener;
+import org.xhtmlrenderer.swing.ImageReplacedElement;
+
+import java.awt.image.BufferedImage;
+import java.util.Map;
+import java.util.function.Function;
+
+import static com.scrivenvar.StatusBarNotifier.alert;
+import static com.scrivenvar.preview.SvgRasterizer.*;
+
+/**
+ * Responsible for running {@link SvgRasterizer} on SVG images detected within
+ * a document to transform them into rasterized versions.
+ */
+public class SvgReplacedElementFactory
+ implements ReplacedElementFactory {
+
+ /**
+ * SVG filename extension maps to an SVG image element.
+ */
+ private static final String SVG_FILE = "svg";
+ private static final String HTML_SVG = "svg";
+
+ /**
+ * The {@code <svg>} element attribute name containing a value that uniquely
+ * identifies the vector graphic file. This value must always be the same for
+ * the same formula. That is, {@code E=mc^2} must always hash the same way
+ * (e.g., by calling {@link String#hashCode()} on the formula).
+ */
+ private static final String SVG_IMAGE_SRC = "id";
+
+ private static final String HTML_IMAGE = "img";
+ private static final String HTML_IMAGE_SRC = "src";
+
+ /**
+ * A bounded cache that removes the oldest image if the maximum number of
+ * cached images has been reached. This constrains the number of images
+ * loaded into memory.
+ */
+ private final Map<String, BufferedImage> mImageCache =
+ new BoundedCache<>( 150 );
+
+ @Override
+ public ReplacedElement createReplacedElement(
+ final LayoutContext c,
+ final BlockBox box,
+ final UserAgentCallback uac,
+ final int cssWidth,
+ final int cssHeight ) {
+ BufferedImage image = null;
+ final var e = box.getElement();
+
+ if( e != null ) {
+ try {
+ final var nodeName = e.getNodeName();
+
+ if( HTML_IMAGE.equals( nodeName ) ) {
+ final var src = e.getAttribute( HTML_IMAGE_SRC );
+ final var ext = FilenameUtils.getExtension( src );
+
+ if( SVG_FILE.equalsIgnoreCase( ext ) ) {
+ image = getCachedImage(
+ src, svg -> rasterize( svg, box.getContentWidth() ) );
+ }
+ }
+ else if( HTML_SVG.equals( nodeName ) ) {
+ // Convert the <svg> element to a raster graphic if it isn't cached.
+ final var src = e.getAttribute( SVG_IMAGE_SRC );
+ image = getCachedImage( src, __ -> rasterizeString( toSvg( e ) ) );
+ }
+ } catch( final Exception ex ) {
+ alert( ex );
+ }
+ }
+
+ if( image != null ) {
+ final var w = image.getWidth( null );
+ final var h = image.getHeight( null );
+
+ return new ImageReplacedElement( image, w, h );
+ }
+
+ return null;
+ }
+
+ @Override
+ public void reset() {
+ }
+
+ @Override
+ public void remove( final Element e ) {
+ }
+
+ @Override
+ public void setFormSubmissionListener( FormSubmissionListener listener ) {
+ }
+
+ /**
+ * Returns an image associated with a string; the string's pre-computed
+ * hash code is returned as the string value, making this operation very
+ * quick to return the corresponding {@link BufferedImage}.
+ *
+ * @param src The SVG used for the key into the image cache.
+ * @param rasterizer {@link Function} to call to convert SVG to an image.
+ * @return The image that corresponds to the given source string.
+ */
+ private BufferedImage getCachedImage(
+ final String src, final Function<String, BufferedImage> rasterizer ) {
+ return mImageCache.computeIfAbsent( src, __ -> rasterizer.apply( src ) );
+ }
+}