X-Git-Url: http://source.jalview.org/gitweb/?a=blobdiff_plain;f=src%2Fjalview%2Futil%2FColorUtils.java;h=042654df778bfdae43ff1721b32989b86460eab3;hb=2f5b2fa149a0bdedff23293ce7c0522b3a3c77ec;hp=b8cd563ddd0d3bccd3f919bbd73c648b92a97617;hpb=49d07daba32cb7ca7841eca72c82cdf3c8d4344d;p=jalview.git

diff --git a/src/jalview/util/ColorUtils.java b/src/jalview/util/ColorUtils.java
index b8cd563..042654d 100644
--- a/src/jalview/util/ColorUtils.java
+++ b/src/jalview/util/ColorUtils.java
@@ -103,4 +103,39 @@ public class ColorUtils
     return col == null ? null : col.brighter().brighter().brighter();
   }
 
+  /**
+   * Returns a color between minColour and maxColour; the RGB values are in
+   * proportion to where 'value' lies between minValue and maxValue
+   * 
+   * @param value
+   * @param minValue
+   * @param minColour
+   * @param maxValue
+   * @param maxColour
+   * @return
+   */
+  public static Color getGraduatedColour(float value, float minValue,
+          Color minColour, float maxValue, Color maxColour)
+  {
+    if (value < minValue)
+    {
+      value = minValue;
+    }
+    if (value > maxValue)
+    {
+      value = maxValue;
+    }
+
+    /*
+     * prop = proportion of the way value is from minValue to maxValue
+     */
+    float prop = (value - minValue) / (maxValue - minValue);
+    float r = minColour.getRed() + prop
+            * (maxColour.getRed() - minColour.getRed());
+    float g = minColour.getGreen() + prop
+            * (maxColour.getGreen() - minColour.getGreen());
+    float b = minColour.getBlue() + prop
+            * (maxColour.getBlue() - minColour.getBlue());
+    return new Color(r / 255, g / 255, b / 255);
+  }
 }