RGBA color filter

gitlab simantics/platform#569

Change-Id: Ia8586426d8079f70ff8312138cd121a60810185b

diff --git a/bundles/org.simantics.scenegraph/src/org/simantics/scenegraph/g2d/color/RGBAColorFilter.java b/bundles/org.simantics.scenegraph/src/org/simantics/scenegraph/g2d/color/RGBAColorFilter.java
new file mode 100644 (file)
index 0000000..3816cb6
--- /dev/null
+++ b/bundles/org.simantics.scenegraph/src/org/simantics/scenegraph/g2d/color/RGBAColorFilter.java
@@ -0,0 +1,73 @@
+/*******************************************************************************
+ * Copyright (c) 2020 Association for Decentralized Information Management in
+ * Industry THTH ry.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Semantum Oy - initial API and implementation
+ *******************************************************************************/
+package org.simantics.scenegraph.g2d.color;
+
+import java.awt.Color;
+
+public class RGBAColorFilter implements ColorFilter {
+
+    private double r, g, b, a;
+    
+    public RGBAColorFilter(double r, double g, double b, double a) {
+        this.r = r;
+        this.g = g;
+        this.b = b;
+        this.a = a;
+    }
+
+    @Override
+    public Color filter(Color c) {
+        int avg = (c.getRed() + c.getGreen() + c.getBlue()) / 3; 
+        int R = Math.min(255, (int)(avg * r));
+        int G = Math.min(255, (int)(avg * g));
+        int B = Math.min(255, (int)(avg * b));
+        int A = Math.min(255, (int)(c.getAlpha() * a));
+        Color c2 = new Color(R, G, B, A);
+        return c2;
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        long temp;
+        temp = Double.doubleToLongBits(a);
+        result = prime * result + (int) (temp ^ (temp >>> 32));
+        temp = Double.doubleToLongBits(b);
+        result = prime * result + (int) (temp ^ (temp >>> 32));
+        temp = Double.doubleToLongBits(g);
+        result = prime * result + (int) (temp ^ (temp >>> 32));
+        temp = Double.doubleToLongBits(r);
+        result = prime * result + (int) (temp ^ (temp >>> 32));
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        RGBAColorFilter other = (RGBAColorFilter) obj;
+        if (Double.doubleToLongBits(a) != Double.doubleToLongBits(other.a))
+            return false;
+        if (Double.doubleToLongBits(b) != Double.doubleToLongBits(other.b))
+            return false;
+        if (Double.doubleToLongBits(g) != Double.doubleToLongBits(other.g))
+            return false;
+        if (Double.doubleToLongBits(r) != Double.doubleToLongBits(other.r))
+            return false;
+        return true;
+    }
+}