From 64877ac92b1503e6f5261e2483ca5d96210b9d39 Mon Sep 17 00:00:00 2001
From: DJGummikuh <djgummikuh@gmail.com>
Date: Sat, 26 Feb 2022 11:45:00 +0100
Subject: [PATCH] Adding possibility to set the web fill alpha value so it's
 not locked to 0.1f

---
 .../org/jfree/chart/plot/SpiderWebPlot.java   | 37 +++++++++++++++++--
 1 file changed, 34 insertions(+), 3 deletions(-)

diff --git a/src/main/java/org/jfree/chart/plot/SpiderWebPlot.java b/src/main/java/org/jfree/chart/plot/SpiderWebPlot.java
index 6a71e689c4..9abfa0ae57 100644
--- a/src/main/java/org/jfree/chart/plot/SpiderWebPlot.java
+++ b/src/main/java/org/jfree/chart/plot/SpiderWebPlot.java
@@ -252,6 +252,9 @@ public class SpiderWebPlot extends Plot implements Cloneable, Serializable {
     /** controls if the web polygons are filled or not */
     private boolean webFilled = true;
 
+    /** The alpha value of the fill portion of a polygon. */
+    private float webFillAlpha = 0.1F;
+
     /** A tooltip generator for the plot ({@code null} permitted). */
     private CategoryToolTipGenerator toolTipGenerator;
 
@@ -392,6 +395,34 @@ public void setWebFilled(boolean flag) {
         fireChangeEvent();
     }
 
+
+    /**
+     * Method to set the alpha value for the fill of a plot polygon.
+     *
+     * @param alpha the new alpha value. If it is outsite [0,1] it will be corrected to fit the range.
+     * @see #getWebFillAlpha()
+     */
+    public void setWebFillAlpha(float alpha) {
+        this.webFillAlpha = alpha;
+        if (webFillAlpha < 0f) {
+            webFillAlpha = 0f;
+        } else if (webFillAlpha > 1f) {
+            webFillAlpha = 1f;
+        }
+        fireChangeEvent();
+    }
+
+    /**
+     * Method to return the alpha value for filling a graph.
+     *
+     * @return The alpha value for filling a spider plot polygon.
+     *
+     * @see #setWebFillAlpha(float)
+     */
+    public float getWebFillAlpha() {
+        return webFillAlpha;
+    }
+
     /**
      * Returns the data extract order (by row or by column).
      *
@@ -648,8 +679,8 @@ public Paint getSeriesPaint() {
     }
 
     /**
-     * Sets the paint for ALL series in the plot.  If this is set to 
-     * {@code null}, then a list of paints is used instead (to allow different 
+     * Sets the paint for ALL series in the plot.  If this is set to
+     * {@code null}, then a list of paints is used instead (to allow different
      * colors to be used for each series of the radar group).
      *
      * @param paint the paint ({@code null} permitted).
@@ -1343,7 +1374,7 @@ protected void drawRadarPoly(Graphics2D g2,
 
         if (this.webFilled) {
             g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER,
-                    0.1f));
+                    webFillAlpha));
             g2.fill(polygon);
             g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER,
                     getForegroundAlpha()));