FlatSVGIcon: some additions to PR #817:

- create new `LinearGradientPaint` only if color has changed
- preserve old `LinearGradientPaint.colorSpace` and `transform`

CHANGELOG.md

@@ -1,6 +1,13 @@
 FlatLaf Change Log
 ==================
 
+## 3.5-SNAPSHOT
+
+#### Fixed bugs
+
+- Extras: `FlatSVGIcon` color filters now support linear gradients. (PR #817)
+
+
 ## 3.4
 
 #### New features and improvements

flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatSVGIcon.java

@@ -985,11 +985,12 @@ public class FlatSVGIcon
 				paint = filterColor( (Color) paint );
 			else if( paint instanceof LinearGradientPaint ) {
 				LinearGradientPaint oldPaint = (LinearGradientPaint) paint;
-				paint = new LinearGradientPaint( oldPaint.getStartPoint(),
+				Color[] newColors = filterColors( oldPaint.getColors() );
-					oldPaint.getEndPoint(),
+				if( newColors != null ) {
-					oldPaint.getFractions(),
+					paint = new LinearGradientPaint( oldPaint.getStartPoint(), oldPaint.getEndPoint(),
-					filterColors( oldPaint.getColors() ),
+						oldPaint.getFractions(), newColors, oldPaint.getCycleMethod(),
-					oldPaint.getCycleMethod() );
+						oldPaint.getColorSpace(), oldPaint.getTransform() );
+				}
 			}
 			super.setPaint( paint );
 		}
@@ -1013,9 +1014,12 @@ public class FlatSVGIcon
 
 		private Color[] filterColors( Color[] colors ) {
 			Color[] newColors = new Color[colors.length];
-			for( int i = 0; i < colors.length; i++ )
+			boolean changed = false;
+			for( int i = 0; i < colors.length; i++ ) {
 				newColors[i] = filterColor( colors[i] );
-			return newColors;
+				changed = (changed || newColors[i] != colors[i]);
+			}
+			return changed ? newColors : null;
 		}
 	}
 }

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/extras/FlatExtrasTest.java

@@ -16,6 +16,7 @@
 
 package com.formdev.flatlaf.testing.extras;
 
+import java.awt.*;
 import javax.swing.*;
 import com.formdev.flatlaf.extras.*;
 import com.formdev.flatlaf.extras.components.*;
@@ -75,6 +76,12 @@ public class FlatExtrasTest
 		disabledTabbedPane2.setIconAt( 0, icon );
 		disabledTabbedPane2.setDisabledIconAt( 0, disabledIcon );
 
+		addJSVGIcon( "linearGradient.svg", 64, 128 );
+		addJSVGIcon( "stripes.svg", 128, 128 );
+		addJSVGIcon( "gradientText0.svg", 128, 128 );
+		addJSVGIcon( "gradientText1.svg", 128, 128 );
+		addJSVGIcon( "gradientText2.svg", 128, 128 );
+
 		disabledChanged();
 	}
 
@@ -82,6 +89,10 @@ public class FlatExtrasTest
 		svgIconsPanel.add( new JLabel( new FlatSVGIcon( "com/formdev/flatlaf/demo/extras/svg/" + name ) ) );
 	}
 
+	private void addJSVGIcon( String name, int width, int height ) {
+		gradientIconsPanel.add( new JLabel( new FlatSVGIcon( "com/formdev/flatlaf/testing/extras/jsvg/" + name, width, height ) ) );
+	}
+
 	private void triStateCheckBox1Changed() {
 		triStateLabel1.setText( triStateCheckBox1.getState().toString() );
 	}
@@ -104,6 +115,9 @@ public class FlatExtrasTest
 		disabledLabel2.setEnabled( enabled );
 		disabledButton2.setEnabled( enabled );
 		disabledTabbedPane2.setEnabledAt( 0, enabled );
+
+		for( Component c : gradientIconsPanel.getComponents() )
+			c.setEnabled( enabled );
 	}
 
 	@Override
@@ -141,6 +155,7 @@ public class FlatExtrasTest
 		disabledButton2 = new JButton();
 		disabledTabbedPane2 = new JTabbedPane();
 		label6 = new JLabel();
+		gradientIconsPanel = new JPanel();
 
 		//======== this ========
 		setLayout(new MigLayout(
@@ -156,6 +171,7 @@ public class FlatExtrasTest
 			"[]" +
 			"[]" +
 			"[]" +
+			"[]" +
 			"[]"));
 
 		//---- label1 ----
@@ -251,6 +267,12 @@ public class FlatExtrasTest
 		label6.setText("setIcon() and setDisabledIcon()");
 		label6.setEnabled(false);
 		add(label6, "cell 1 6 2 1,gapx 20");
+
+		//======== gradientIconsPanel ========
+		{
+			gradientIconsPanel.setLayout(new FlowLayout());
+		}
+		add(gradientIconsPanel, "cell 1 7 2 1");
 		// JFormDesigner - End of component initialization  //GEN-END:initComponents
 	}
 
@@ -275,5 +297,6 @@ public class FlatExtrasTest
 	private JButton disabledButton2;
 	private JTabbedPane disabledTabbedPane2;
 	private JLabel label6;
+	private JPanel gradientIconsPanel;
 	// JFormDesigner - End of variables declaration  //GEN-END:variables
 }

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/extras/FlatExtrasTest.jfd

@@ -1,4 +1,4 @@
-JFDML JFormDesigner: "7.0.3.1.342" Java: "15" encoding: "UTF-8"
+JFDML JFormDesigner: "8.2.0.0.331" Java: "21" encoding: "UTF-8"
 
 new FormModel {
 	contentType: "form/swing"
@@ -6,7 +6,7 @@ new FormModel {
 		add( new FormContainer( "com.formdev.flatlaf.testing.FlatTestPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 			"$layoutConstraints": "ltr,insets dialog,hidemode 3"
 			"$columnConstraints": "[][][left]"
-			"$rowConstraints": "[][][][][][][]"
+			"$rowConstraints": "[][][][][][][][]"
 		} ) {
 			name: "this"
 			add( new FormComponent( "javax.swing.JLabel" ) {
@@ -143,9 +143,14 @@ new FormModel {
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 1 6 2 1,gapx 20"
 			} )
+			add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class java.awt.FlowLayout ) ) {
+				name: "gradientIconsPanel"
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 1 7 2 1"
+			} )
 		}, new FormLayoutConstraints( null ) {
 			"location": new java.awt.Point( 0, 0 )
-			"size": new java.awt.Dimension( 595, 470 )
+			"size": new java.awt.Dimension( 645, 470 )
 		} )
 	}
 }

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/extras/jsvg/LICENSE.txt

@@ -0,0 +1,3 @@
+The SVG icons in this folder are from JSVG,
+which is licensed under the MIT License
+See: https://github.com/weisJ/jsvg

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/extras/jsvg/gradientText0.svg

@@ -0,0 +1,12 @@
+<svg viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg"
+	stroke="none">
+	<defs>
+		<linearGradient id="myGradient"
+			gradientTransform="rotate(90)">
+			<stop offset="5%" stop-color="gold" />
+			<stop offset="95%" stop-color="red" />
+		</linearGradient>
+	</defs>
+	<rect x="0" y="50" width="100" height="40" fill="url(#myGradient)" />
+	<text x="0" y="50" fill="url(#myGradient)">Hello lovely World!</text>
+</svg>

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/extras/jsvg/gradientText1.svg

@@ -0,0 +1,14 @@
+<svg viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg"
+	stroke="none">
+	<defs>
+		<linearGradient id="myGradient">
+			<stop offset="5%" stop-color="gold" />
+			<stop offset="95%" stop-color="red" />
+		</linearGradient>
+	</defs>
+	<text x="0" y="50">
+		Hello
+		<tspan fill="url(#myGradient)">lovely</tspan>
+		World!
+	</text>
+</svg>

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/extras/jsvg/gradientText2.svg

@@ -0,0 +1,14 @@
+<svg viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg"
+	stroke="none">
+	<defs>
+		<linearGradient id="myGradient">
+			<stop offset="5%" stop-color="gold" />
+			<stop offset="95%" stop-color="red" />
+		</linearGradient>
+	</defs>
+	<text x="0" y="50" fill="url(#myGradient)">
+		Hello
+		<tspan>lovely</tspan>
+		World!
+	</text>
+</svg>

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/extras/jsvg/linearGradient.svg

@@ -0,0 +1,23 @@
+<svg width="120" height="240" version="1.1"
+	xmlns="http://www.w3.org/2000/svg">
+	<defs>
+		<linearGradient id="Gradient1"
+			gradientUnits="objectBoundingBox">
+			<stop offset="0%" stop-color="red" />
+			<stop offset="50%" stop-color="black" stop-opacity="0" />
+			<stop offset="100%" stop-color="blue" />
+		</linearGradient>
+		<linearGradient id="Gradient2" x1="0" x2="0" y1="0"
+			y2="1">
+			<stop offset="0%" stop-color="red" />
+			<stop offset="50%" stop-color="black" stop-opacity="0" />
+			<stop offset="100%" stop-color="blue" />
+		</linearGradient>
+	</defs>
+
+	<rect id="rect1" x="10" y="10" rx="15" ry="15" width="100"
+		height="100" fill="url(#Gradient1)" />
+	<rect x="10" y="120" rx="15" ry="15" width="100" height="100"
+		fill="url(#Gradient2)" />
+
+</svg>

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/extras/jsvg/stripes.svg

@@ -0,0 +1,27 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="500px" height="500px">
+	<defs>
+		<linearGradient id="stripes">
+			<stop offset="0%" stop-color="red" />
+			<stop offset="10%" stop-color="red" />
+			<stop offset="10%" stop-color="orange" />
+			<stop offset="20%" stop-color="orange" />
+			<stop offset="20%" stop-color="yellow" />
+			<stop offset="30%" stop-color="yellow" />
+			<stop offset="30%" stop-color="lightgreen" />
+			<stop offset="40%" stop-color="lightgreen" />
+			<stop offset="40%" stop-color="green" />
+			<stop offset="50%" stop-color="green" />
+			<stop offset="50%" stop-color="purple" />
+			<stop offset="60%" stop-color="purple" />
+			<stop offset="60%" stop-color="blue" />
+			<stop offset="70%" stop-color="blue" />
+			<stop offset="70%" stop-color="skyblue" />
+			<stop offset="80%" stop-color="skyblue" />
+			<stop offset="80%" stop-color="pink" />
+			<stop offset="90%" stop-color="pink" />
+			<stop offset="90%" stop-color="white" />
+			<stop offset="100%" stop-color="white" />
+		</linearGradient>
+	</defs>
+	<rect width="100%" height="100%" fill="url(#stripes)" />
+</svg>