Follow-up to 54b14d6: parse rem, rex, rlh units with native parser

css4j · Oct 19, 2024 · 2ad9989 · 2ad9989
1 parent 5f71fd5
commit 2ad9989
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Showing 14 changed files with 243 additions and 21 deletions.
diff --git a/echosvg-anim/src/main/java/io/sf/carte/echosvg/anim/dom/AbstractSVGLength.java b/echosvg-anim/src/main/java/io/sf/carte/echosvg/anim/dom/AbstractSVGLength.java
@@ -357,6 +357,11 @@ public float getRootFontSize() {
 			return getAssociatedElement().getSVGContext().getRootFontSize();
 		}
 
+		@Override
+		public float getRootXHeight() {
+			return 0.5f;
+		}
+
 		@Override
 		public float getRootLineHeight() {
 			return getAssociatedElement().getSVGContext().getRootLineHeight();

diff --git a/echosvg-anim/src/main/java/io/sf/carte/echosvg/anim/dom/SVGOMElement.java b/echosvg-anim/src/main/java/io/sf/carte/echosvg/anim/dom/SVGOMElement.java
@@ -912,6 +912,11 @@ public float getXHeight() {
 			return 0.5f;
 		}
 
+		@Override
+		public float getRootXHeight() {
+			return 0.5f;
+		}
+
 		/**
 		 * Returns the viewport width used to compute units.
 		 */

diff --git a/echosvg-bridge/src/main/java/io/sf/carte/echosvg/bridge/AbstractGraphicsNodeBridge.java b/echosvg-bridge/src/main/java/io/sf/carte/echosvg/bridge/AbstractGraphicsNodeBridge.java
@@ -23,6 +23,7 @@
 import java.awt.geom.Rectangle2D;
 import java.lang.ref.SoftReference;
 
+import org.w3c.css.om.unit.CSSUnit;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.events.DocumentEvent;
@@ -35,9 +36,12 @@
 import io.sf.carte.echosvg.anim.dom.AnimatedLiveAttributeValue;
 import io.sf.carte.echosvg.anim.dom.SVGOMAnimatedTransformList;
 import io.sf.carte.echosvg.anim.dom.SVGOMElement;
+import io.sf.carte.echosvg.css.CSSSecurityException;
 import io.sf.carte.echosvg.css.engine.CSSEngine;
 import io.sf.carte.echosvg.css.engine.CSSEngineEvent;
 import io.sf.carte.echosvg.css.engine.SVGCSSEngine;
+import io.sf.carte.echosvg.css.engine.value.LengthManager;
+import io.sf.carte.echosvg.css.engine.value.Value;
 import io.sf.carte.echosvg.dom.events.AbstractEvent;
 import io.sf.carte.echosvg.dom.svg.AbstractSVGTransformList;
 import io.sf.carte.echosvg.dom.svg.LiveAttributeException;
@@ -603,27 +607,59 @@ public float getViewportHeight() {
 	 */
 	@Override
 	public float getFontSize() {
-		return CSSUtilities.getComputedStyle(e, SVGCSSEngine.FONT_SIZE_INDEX).getFloatValue();
+		return fontSizeValue(e);
 	}
 
 	/**
 	 * Returns the line-height on the associated element.
 	 */
 	@Override
 	public float getLineHeight() {
-		return CSSUtilities.getComputedStyle(e, SVGCSSEngine.LINE_HEIGHT_INDEX).getFloatValue();
+		return lineHeightValue(e);
 	}
 
 	@Override
 	public float getRootFontSize() {
 		Element root = e.getOwnerDocument().getDocumentElement();
-		return CSSUtilities.getComputedStyle(root, SVGCSSEngine.FONT_SIZE_INDEX).getFloatValue();
+		return fontSizeValue(root);
 	}
 
 	@Override
 	public float getRootLineHeight() {
 		Element root = e.getOwnerDocument().getDocumentElement();
-		return CSSUtilities.getComputedStyle(root, SVGCSSEngine.LINE_HEIGHT_INDEX).getFloatValue();
+		return lineHeightValue(root);
+	}
+
+	private float fontSizeValue(Element elt) {
+		try {
+			return CSSUtilities.getComputedStyle(elt, SVGCSSEngine.FONT_SIZE_INDEX).getFloatValue();
+		} catch (CSSSecurityException ex) {
+		}
+
+		if (ctx != null) {
+			return ctx.getUserAgent().getMediumFontSize();
+		}
+
+		return 12f;
+	}
+
+	private float lineHeightValue(Element elt) {
+		Value v;
+		try {
+			v = CSSUtilities.getComputedStyle(elt, SVGCSSEngine.LINE_HEIGHT_INDEX);
+		} catch (CSSSecurityException ex) {
+			return fontSizeValue(elt) * LengthManager.DEFAULT_LINE_HEIGHT;
+		}
+
+		float fv = v.getFloatValue();
+		short unit = v.getUnitType();
+		if (unit == CSSUnit.CSS_NUMBER) {
+			float fs = fontSizeValue(elt);
+			return fs * fv;
+		}
+
+		// Must be pixels
+		return fv;
 	}
 
 }
diff --git a/echosvg-bridge/src/main/java/io/sf/carte/echosvg/bridge/CSSUtilities.java b/echosvg-bridge/src/main/java/io/sf/carte/echosvg/bridge/CSSUtilities.java
@@ -32,6 +32,7 @@
 import io.sf.carte.doc.style.css.CSSValue.Type;
 import io.sf.carte.echosvg.anim.dom.SVGOMDocument;
 import io.sf.carte.echosvg.constants.XMLConstants;
+import io.sf.carte.echosvg.css.CSSSecurityException;
 import io.sf.carte.echosvg.css.engine.CSSEngine;
 import io.sf.carte.echosvg.css.engine.CSSStylableElement;
 import io.sf.carte.echosvg.css.engine.SVGCSSEngine;
@@ -78,7 +79,7 @@ public static CSSEngine getCSSEngine(Element e) {
 	/**
 	 * Returns the computed style of the given property.
 	 */
-	public static Value getComputedStyle(Element e, int property) {
+	public static Value getComputedStyle(Element e, int property) throws CSSSecurityException {
 		CSSEngine engine = getCSSEngine(e);
 		if (engine == null)
 			return null;

diff --git a/echosvg-bridge/src/main/java/io/sf/carte/echosvg/bridge/UnitProcessor.java b/echosvg-bridge/src/main/java/io/sf/carte/echosvg/bridge/UnitProcessor.java
@@ -348,6 +348,11 @@ public float getXHeight() {
 			return 0.5f;
 		}
 
+		@Override
+		public float getRootXHeight() {
+			return 0.5f;
+		}
+
 		/**
 		 * Returns the viewport width used to compute units.
 		 */

diff --git a/echosvg-css/src/main/java/io/sf/carte/echosvg/css/engine/value/LengthManager.java b/echosvg-css/src/main/java/io/sf/carte/echosvg/css/engine/value/LengthManager.java
@@ -56,7 +56,7 @@ public abstract class LengthManager extends AbstractValueManager {
 	 * on a path". Web browsers use a default based on the font family, close to 1.2
 	 * </p>
 	 */
-	protected static final float DEFAULT_LINE_HEIGHT = 1.1f;
+	public static final float DEFAULT_LINE_HEIGHT = 1.1f;
 
 	/**
 	 * precomputed square-root of 2.0

diff --git a/echosvg-parser/src/main/java/io/sf/carte/echosvg/parser/DefaultLengthHandler.java b/echosvg-parser/src/main/java/io/sf/carte/echosvg/parser/DefaultLengthHandler.java
@@ -99,6 +99,21 @@ public void percentage() throws ParseException {
 		setUnit(CSSUnit.CSS_PERCENTAGE);
 	}
 
+	@Override
+	public void rem() throws ParseException {
+		setUnit(CSSUnit.CSS_REM);
+	}
+
+	@Override
+	public void rex() throws ParseException {
+		setUnit(CSSUnit.CSS_REX);
+	}
+
+	@Override
+	public void rlh() throws ParseException {
+		setUnit(CSSUnit.CSS_RLH);
+	}
+
 	@Override
 	public void vh() throws ParseException {
 		setUnit(CSSUnit.CSS_VH);

diff --git a/echosvg-parser/src/main/java/io/sf/carte/echosvg/parser/LengthHandler.java b/echosvg-parser/src/main/java/io/sf/carte/echosvg/parser/LengthHandler.java
@@ -114,6 +114,27 @@ public interface LengthHandler {
 	 */
 	void percentage() throws ParseException;
 
+	/**
+	 * Invoked when 'rem' has been parsed.
+	 * 
+	 * @exception ParseException if an error occurs while processing the length
+	 */
+	void rem() throws ParseException;
+
+	/**
+	 * Invoked when 'rex' has been parsed.
+	 * 
+	 * @exception ParseException if an error occurs while processing the length
+	 */
+	void rex() throws ParseException;
+
+	/**
+	 * Invoked when 'rlh' has been parsed.
+	 * 
+	 * @exception ParseException if an error occurs while processing the length
+	 */
+	void rlh() throws ParseException;
+
 	/**
 	 * Invoked when 'vh' has been parsed.
 	 * 

diff --git a/echosvg-parser/src/main/java/io/sf/carte/echosvg/parser/LengthParser.java b/echosvg-parser/src/main/java/io/sf/carte/echosvg/parser/LengthParser.java
@@ -450,6 +450,37 @@ protected void parseLength() throws ParseException, IOException {
 			lengthHandler.percentage();
 			current = reader.read();
 			break;
+		case 'r':
+			current = reader.read();
+			switch (current) {
+			case 'e':
+				current = reader.read();
+				switch (current) {
+				case 'm':
+					lengthHandler.rem();
+					current = reader.read();
+					break;
+				case 'x':
+					lengthHandler.rex();
+					current = reader.read();
+					break;
+				default:
+					reportUnexpectedCharacterError(current);
+				}
+				break;
+			case 'l':
+				current = reader.read();
+				if (current != 'h') {
+					reportCharacterExpectedError('h', current);
+					break;
+				}
+				lengthHandler.rlh();
+				current = reader.read();
+				break;
+			default:
+				reportUnexpectedCharacterError(current);
+			}
+			break;
 		case 'v':
 			current = reader.read();
 			switch (current) {
@@ -462,6 +493,7 @@ protected void parseLength() throws ParseException, IOException {
 				current = reader.read();
 				break;
 			case 'm':
+				current = reader.read();
 				switch (current) {
 				case 'i':
 					current = reader.read();

diff --git a/echosvg-parser/src/main/java/io/sf/carte/echosvg/parser/UnitProcessor.java b/echosvg-parser/src/main/java/io/sf/carte/echosvg/parser/UnitProcessor.java
@@ -143,6 +143,12 @@ public static float cssToUserSpace(float v, short type, short d, Context ctx) {
 			return exsToPixels(v, d, ctx);
 		case CSSUnit.CSS_LH:
 			return lhToPixels(v, d, ctx);
+		case CSSUnit.CSS_REM:
+			return remToPixels(v, d, ctx);
+		case CSSUnit.CSS_REX:
+			return rexToPixels(v, d, ctx);
+		case CSSUnit.CSS_RLH:
+			return rlhToPixels(v, d, ctx);
 		case CSSUnit.CSS_VW:
 			return vwToPixels(v, d, ctx);
 		case CSSUnit.CSS_VH:
@@ -201,6 +207,12 @@ public static float userSpaceToCSS(float v, short type, short d, Context ctx) {
 			return pixelsToExs(v, d, ctx);
 		case CSSUnit.CSS_LH:
 			return pixelsToLh(v, d, ctx);
+		case CSSUnit.CSS_REM:
+			return pixelsToRem(v, d, ctx);
+		case CSSUnit.CSS_REX:
+			return pixelsToRex(v, d, ctx);
+		case CSSUnit.CSS_RLH:
+			return pixelsToRlh(v, d, ctx);
 		case CSSUnit.CSS_VW:
 			return pixelsToVw(v, d, ctx);
 		case CSSUnit.CSS_VH:
@@ -354,6 +366,30 @@ protected static float remToPixels(float v, short d, Context ctx) {
 		return v * ctx.getRootFontSize();
 	}
 
+	/**
+	 * Converts user units to rex units.
+	 *
+	 * @param v   the value to convert
+	 * @param d   HORIZONTAL_LENGTH, VERTICAL_LENGTH, or OTHER_LENGTH
+	 * @param ctx the context
+	 */
+	protected static float pixelsToRex(float v, short d, Context ctx) {
+		float xh = ctx.getRootXHeight();
+		return v / xh / ctx.getRootFontSize();
+	}
+
+	/**
+	 * Converts rex units to user units.
+	 *
+	 * @param v   the value to convert
+	 * @param d   HORIZONTAL_LENGTH, VERTICAL_LENGTH, or OTHER_LENGTH
+	 * @param ctx the context
+	 */
+	protected static float rexToPixels(float v, short d, Context ctx) {
+		float xh = ctx.getRootXHeight();
+		return v * xh * ctx.getRootFontSize();
+	}
+
 	/**
 	 * Converts user units to rlh units.
 	 *
@@ -495,6 +531,11 @@ public interface Context {
 		 */
 		float getRootFontSize();
 
+		/**
+		 * Returns the x-height value of the :root element.
+		 */
+		float getRootXHeight();
+
 		/**
 		 * Returns the line-height value of the :root element.
 		 */

diff --git a/echosvg-test/src/test/java/io/sf/carte/echosvg/parser/test/LengthParserTest.java b/echosvg-test/src/test/java/io/sf/carte/echosvg/parser/test/LengthParserTest.java
@@ -73,6 +73,20 @@ public void test() throws Exception {
 		testLengthParser("-0px", "0.0px");
 
 		testLengthParser("0000%", "0.0%");
+
+		testLengthParser("1rem", "1.0rem");
+
+		testLengthParser("02rex", "2.0rex");
+
+		testLengthParser("2rlh", "2.0rlh");
+
+		testLengthParser(".2vh", "0.2vh");
+
+		testLengthParser("2vw", "2.0vw");
+
+		testLengthParser("2.667vmin", "2.667vmin");
+
+		testLengthParser("2.3vmax", "2.3vmax");
 	}
 
 	private class TestHandler extends DefaultLengthHandler {
@@ -143,6 +157,21 @@ public void percentage() throws ParseException {
 			buffer.append("%");
 		}
 
+		@Override
+		public void rem() throws ParseException {
+			buffer.append("rem");
+		}
+
+		@Override
+		public void rex() throws ParseException {
+			buffer.append("rex");
+		}
+
+		@Override
+		public void rlh() throws ParseException {
+			buffer.append("rlh");
+		}
+
 		@Override
 		public void vh() throws ParseException {
 			buffer.append("vh");

diff --git a/test-references/io/sf/carte/echosvg/transcoder/image/resolution72dpi.png b/test-references/io/sf/carte/echosvg/transcoder/image/resolution72dpi.png
diff --git a/test-references/io/sf/carte/echosvg/transcoder/image/resolution96dpi.png b/test-references/io/sf/carte/echosvg/transcoder/image/resolution96dpi.png