Change directory structure.

[dvibrowser/dvi2epub.git] / src / main / java / jp / sourceforge / dvibrowser / dvicore / render / DefaultGammaCorrector.java

diff --git a/src/main/java/jp/sourceforge/dvibrowser/dvicore/render/DefaultGammaCorrector.java b/src/main/java/jp/sourceforge/dvibrowser/dvicore/render/DefaultGammaCorrector.java
new file mode 100644 (file)
index 0000000..8f889bf
--- /dev/null
+++ b/src/main/java/jp/sourceforge/dvibrowser/dvicore/render/DefaultGammaCorrector.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2009, Takeyuki Nagao
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the
+ * following conditions are met:
+ * 
+ *  * Redistributions of source code must retain the above
+ *    copyright notice, this list of conditions and the
+ *    following disclaimer.
+ *  * Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the
+ *    following disclaimer in the documentation and/or other
+ *    materials provided with the distribution.
+ *    
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ */
+
+package jp.sourceforge.dvibrowser.dvicore.render;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+import jp.sourceforge.dvibrowser.dvicore.api.GammaCorrector;
+
+
+public class DefaultGammaCorrector
+implements GammaCorrector
+{
+  private static final AtomicLong serializer = new AtomicLong();
+  private final double factor, exponent;
+  private final long serial;
+
+  public DefaultGammaCorrector()
+  {
+    this(1.0, 1.0);
+  }
+  
+  public DefaultGammaCorrector(double factor, double exponent)
+  {
+    this.factor = factor;
+    this.exponent = exponent;
+    this.serial = serializer.incrementAndGet();
+  }
+
+  public double factor() { return factor; }
+  public double exponent() { return exponent; }
+
+  public int correctGamma(int c, int maxval)
+  {
+    return (int) (
+        1024 *
+          Math.min(
+            1.0,
+            Math.pow(factor * c / maxval, exponent)
+          )
+        + 0.5
+      );
+  }
+  
+  @Override
+  public int hashCode() {
+    return (int) (33 * (factor + 33 * exponent));
+  }
+  
+  @Override
+  public boolean equals(Object o) {
+    if (!(o instanceof DefaultGammaCorrector)) return false;
+    DefaultGammaCorrector gc = (DefaultGammaCorrector) o;
+    return (factor == gc.factor && exponent == gc.exponent);
+  }
+  
+  public String getCacheKey() {
+    return getClass().getName() + "--" + serial;
+  }
+  
+  @Override
+  public String toString() {
+    return getClass().getName() + "[factor=" + factor+ ",exponent=" + exponent + "]";
+  }
+}