SVG: Initial implementation of stroke-dasharray attribute

svg/src/main/java/com/itextpdf/svg/css/SvgStrokeParameterConverter.java

@@ -0,0 +1,94 @@
+package com.itextpdf.svg.css;
+
+import com.itextpdf.styledxmlparser.css.util.CssDimensionParsingUtils;
+import com.itextpdf.styledxmlparser.css.util.CssTypesValidationUtils;
+import com.itextpdf.svg.SvgConstants;
+import com.itextpdf.svg.logs.SvgLogMessageConstant;
+import com.itextpdf.svg.utils.SvgCssUtils;
+
+import java.util.Arrays;
+import java.util.List;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This class converts stroke-related SVG parameters and attributes into those from PDF specification
+ */
+public class SvgStrokeParameterConverter {
+
+    private SvgStrokeParameterConverter() {
+    }
+
+    private static Logger LOGGER = LoggerFactory.getLogger(SvgStrokeParameterConverter.class);
+
+    public static PdfLineDashParameters convertStrokeDashArray(String strokeDashArray) {
+        if (!SvgConstants.Values.NONE.equalsIgnoreCase(strokeDashArray)) {
+            List<String> dashArray = SvgCssUtils.splitValueList(strokeDashArray);
+
+            for (String dashArrayItem : dashArray) {
+                if (CssTypesValidationUtils.isPercentageValue(dashArrayItem)) {
+                    LOGGER.error(SvgLogMessageConstant.PERCENTAGE_VALUES_IN_STROKE_DASHARRAY_ARE_NOT_SUPPORTED);
+                    return null;
+                }
+            }
+
+            if (dashArray.size() > 0) {
+                if (dashArray.size() % 2 == 1) {
+                    // If an odd number of values is provided, then the list of values is repeated to yield an even
+                    // number of values. Thus, 5,3,2 is equivalent to 5,3,2,5,3,2.
+                    dashArray.addAll(dashArray);
+                }
+                float[] dashArrayFloat = new float[dashArray.size()];
+                for (int i = 0; i < dashArray.size(); i++) {
+                    dashArrayFloat[i] = CssDimensionParsingUtils.parseAbsoluteLength(dashArray.get(i));
+                }
+                return new PdfLineDashParameters(dashArrayFloat, 0);
+            }
+        }
+        return null;
+    }
+
+    public static class PdfLineDashParameters {
+        private float[] lengths;
+        private float phase;
+
+        public PdfLineDashParameters(float[] lengths, float phase) {
+            this.lengths = lengths;
+            this.phase = phase;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+
+            PdfLineDashParameters that = (PdfLineDashParameters) o;
+
+            if (Float.compare(that.phase, phase) != 0) {
+                return false;
+            }
+            return Arrays.equals(lengths, that.lengths);
+        }
+
+        @Override
+        public int hashCode() {
+            int result = Arrays.hashCode(lengths);
+            result = 31 * result + (phase != +0.0f ? Float.floatToIntBits(phase) : 0);
+            return result;
+        }
+
+
+        public float[] getLengths() {
+            return lengths;
+        }
+
+        public float getPhase() {
+            return phase;
+        }
+    }
+
+}

svg/src/main/java/com/itextpdf/svg/logs/SvgLogMessageConstant.java

@@ -81,6 +81,9 @@ public final class SvgLogMessageConstant {
     public static final String PATTERN_WIDTH_OR_HEIGHT_IS_NEGATIVE =
             "Pattern width or height is negative value. This pattern will not be rendered.";
 
+    public static final String PERCENTAGE_VALUES_IN_STROKE_DASHARRAY_ARE_NOT_SUPPORTED =
+            "Percentage values in 'stroke-dasharray' attribute are not supported. Attribute will be ignored completely";
+
     public static final String MISSING_WIDTH =
             "Top Svg tag has no defined width attribute and viewbox width is not present, so browser default of 300px "
                     + "is used";

svg/src/main/java/com/itextpdf/svg/renderers/impl/AbstractSvgNodeRenderer.java

@@ -45,7 +45,6 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.colors.Color;
 import com.itextpdf.kernel.colors.ColorConstants;
 import com.itextpdf.kernel.colors.DeviceRgb;
-import com.itextpdf.kernel.colors.WebColors;
 import com.itextpdf.kernel.geom.AffineTransform;
 import com.itextpdf.kernel.geom.Rectangle;
 import com.itextpdf.kernel.pdf.canvas.PdfCanvas;
@@ -62,6 +61,8 @@ This file is part of the iText (R) project.
 import com.itextpdf.styledxmlparser.css.validate.CssDeclarationValidationMaster;
 import com.itextpdf.svg.MarkerVertexType;
 import com.itextpdf.svg.SvgConstants;
+import com.itextpdf.svg.SvgConstants.Attributes;
+import com.itextpdf.svg.css.SvgStrokeParameterConverter;
 import com.itextpdf.svg.css.impl.SvgNodeRendererInheritanceResolver;
 import com.itextpdf.svg.renderers.IMarkerCapable;
 import com.itextpdf.svg.renderers.ISvgNodeRenderer;
@@ -320,9 +321,9 @@ void preDraw(SvgDrawContext context) {
 
             PdfExtGState opacityGraphicsState = new PdfExtGState();
             if (!partOfClipPath) {
-                float generalOpacity = getOpacity();
                 // fill
                 {
+                    float generalOpacity = getOpacity();
                     String fillRawValue = getAttributeOrDefault(SvgConstants.Attributes.FILL, "black");
                     this.doFill = !SvgConstants.Values.NONE.equalsIgnoreCase(fillRawValue);
 
@@ -349,47 +350,9 @@ void preDraw(SvgDrawContext context) {
                         currentCanvas.setFillColor(fillColor);
                     }
                 }
-                // stroke
-                {
-                    String strokeRawValue = getAttributeOrDefault(SvgConstants.Attributes.STROKE,
-                            SvgConstants.Values.NONE);
-
-                    if (!SvgConstants.Values.NONE.equalsIgnoreCase(strokeRawValue)) {
-                        String strokeWidthRawValue = getAttribute(SvgConstants.Attributes.STROKE_WIDTH);
-
-                        // 1 px = 0,75 pt
-                        float strokeWidth = 0.75f;
-
-                        if (strokeWidthRawValue != null) {
-                            strokeWidth = CssDimensionParsingUtils.parseAbsoluteLength(strokeWidthRawValue);
-                        }
 
-                        float strokeOpacity = getOpacityByAttributeName(SvgConstants.Attributes.STROKE_OPACITY,
-                                generalOpacity);
-
-                        Color strokeColor = null;
-                        TransparentColor transparentColor = getColorFromAttributeValue(
-                                context, strokeRawValue, (float) ((double) strokeWidth / 2.0), strokeOpacity);
-                        if (transparentColor != null) {
-                            strokeColor = transparentColor.getColor();
-                            strokeOpacity = transparentColor.getOpacity();
-                        }
+                applyStrokeProperties(context, currentCanvas, opacityGraphicsState);
 
-                        if (!CssUtils.compareFloats(strokeOpacity, 1f)) {
-                            opacityGraphicsState.setStrokeOpacity(strokeOpacity);
-                        }
-
-                        // as default value for stroke is 'none' we should not set
-                        // it in case when value obtaining fails
-                        if (strokeColor != null) {
-                            currentCanvas.setStrokeColor(strokeColor);
-                        }
-
-                        currentCanvas.setLineWidth(strokeWidth);
-
-                        doStroke = true;
-                    }
-                }
                 // opacity
                 {
                     if (!opacityGraphicsState.getPdfObject().isEmpty()) {
@@ -507,4 +470,52 @@ private float getOpacity() {
 
         return result;
     }
+
+    private void applyStrokeProperties(SvgDrawContext context, PdfCanvas currentCanvas, PdfExtGState opacityGraphicsState) {
+        String strokeRawValue = getAttributeOrDefault(SvgConstants.Attributes.STROKE,
+                SvgConstants.Values.NONE);
+        if (!SvgConstants.Values.NONE.equalsIgnoreCase(strokeRawValue)) {
+            String strokeWidthRawValue = getAttribute(SvgConstants.Attributes.STROKE_WIDTH);
+
+            // 1 px = 0,75 pt
+            float strokeWidth = 0.75f;
+
+            if (strokeWidthRawValue != null) {
+                strokeWidth = CssDimensionParsingUtils.parseAbsoluteLength(strokeWidthRawValue);
+            }
+
+            float generalOpacity = getOpacity();
+            float strokeOpacity = getOpacityByAttributeName(SvgConstants.Attributes.STROKE_OPACITY,
+                    generalOpacity);
+
+            Color strokeColor = null;
+            TransparentColor transparentColor = getColorFromAttributeValue(
+                    context, strokeRawValue, (float) ((double) strokeWidth / 2.0), strokeOpacity);
+            if (transparentColor != null) {
+                strokeColor = transparentColor.getColor();
+                strokeOpacity = transparentColor.getOpacity();
+            }
+
+            if (!CssUtils.compareFloats(strokeOpacity, 1f)) {
+                opacityGraphicsState.setStrokeOpacity(strokeOpacity);
+            }
+
+            String strokeDashArrayRawValue = getAttribute(Attributes.STROKE_DASHARRAY);
+            SvgStrokeParameterConverter.PdfLineDashParameters lineDashParameters =
+                    SvgStrokeParameterConverter.convertStrokeDashArray(strokeDashArrayRawValue);
+            if (lineDashParameters != null) {
+                currentCanvas.setLineDash(lineDashParameters.getLengths(), lineDashParameters.getPhase());
+            }
+
+            // as default value for stroke is 'none' we should not set
+            // it in case when value obtaining fails
+            if (strokeColor != null) {
+                currentCanvas.setStrokeColor(strokeColor);
+            }
+
+            currentCanvas.setLineWidth(strokeWidth);
+
+            doStroke = true;
+        }
+    }
 }

svg/src/test/java/com/itextpdf/svg/css/SvgStrokeParameterConverterUnitTest.java

@@ -0,0 +1,36 @@
+package com.itextpdf.svg.css;
+
+import com.itextpdf.svg.css.SvgStrokeParameterConverter.PdfLineDashParameters;
+import com.itextpdf.svg.logs.SvgLogMessageConstant;
+import com.itextpdf.test.ExtendedITextTest;
+import com.itextpdf.test.annotations.LogMessage;
+import com.itextpdf.test.annotations.LogMessages;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class SvgStrokeParameterConverterUnitTest extends ExtendedITextTest {
+
+    @Test
+    @LogMessages(messages = {
+            @LogMessage(messageTemplate =
+                    SvgLogMessageConstant.PERCENTAGE_VALUES_IN_STROKE_DASHARRAY_ARE_NOT_SUPPORTED)})
+    public void testStrokeDashArrayPercentsAreNotSupported() {
+        Assert.assertNull(SvgStrokeParameterConverter.convertStrokeDashArray("5,3%"));
+    }
+
+    @Test
+    public void testStrokeDashArrayOddNumberOfValues() {
+        PdfLineDashParameters result = SvgStrokeParameterConverter.convertStrokeDashArray("5pt");
+        Assert.assertNotNull(result);
+        Assert.assertEquals(0, result.getPhase(), 0);
+        Assert.assertArrayEquals(new float[] {5, 5}, result.getLengths(), 1e-5f);
+    }
+
+    @Test
+    public void testEmptyStrokeDashArray() {
+        PdfLineDashParameters result = SvgStrokeParameterConverter.convertStrokeDashArray("");
+        Assert.assertNull(result);
+    }
+
+}

svg/src/test/java/com/itextpdf/svg/renderers/StrokeTest.java

@@ -80,6 +80,11 @@ public void noLineStrokeWidthTest() throws IOException, InterruptedException {
         convertAndCompare(SOURCE_FOLDER, DESTINATION_FOLDER, "noLineStrokeWidth");
     }
 
+    @Test
+    public void strokeWithDashesTest() throws IOException, InterruptedException {
+        convertAndCompare(SOURCE_FOLDER, DESTINATION_FOLDER, "strokeWithDashes");
+    }
+
     @Test
     //TODO: update cmp-file after DEVSIX-2258
     public void advancedStrokeTest() throws IOException, InterruptedException {