From 8cbc601b4c03e4111b3dd59afe7d0456d807b0ad Mon Sep 17 00:00:00 2001
From: Gary Macbook <gsteele13@gmail.com>
Date: Fri, 23 Aug 2013 10:03:29 +0200
Subject: [PATCH] Added a y=b^data function

---
 spyview/ImageData.C   | 6 ++++++
 spyview/ImageData.H   | 1 +
 spyview/ImageWindow.C | 2 ++
 spyview/spyview.C     | 6 +++++-
 4 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/spyview/ImageData.C b/spyview/ImageData.C
index 6a4c760..7c196fa 100644
--- a/spyview/ImageData.C
+++ b/spyview/ImageData.C
@@ -1092,6 +1092,12 @@ void ImageData::scale(double factor)
     raw_data[i] = raw_data[i]*factor;
 }
 
+void ImageData::power2(double x)
+{
+    for (int i=0; i<width*height; i++)
+      raw_data[i] = pow(x,raw_data[i]);
+}
+
 void ImageData::gamma(double gamma, double epsilon)
 { 
   // This is tricky: what to do if we have a negative power and we get zero?
diff --git a/spyview/ImageData.H b/spyview/ImageData.H
index 9a21c1f..b68cb73 100644
--- a/spyview/ImageData.H
+++ b/spyview/ImageData.H
@@ -301,6 +301,7 @@ public:
   void offset(double offset, bool do_auto);// add an offset
   void scale(double factor); // scale the data
   void gamma(double gamma, double epsilon); // gamma scaling operation on 16 bit data
+  void power2(double x); // y = x^data
 
   // More complicated functions that preserve the images size
 
diff --git a/spyview/ImageWindow.C b/spyview/ImageWindow.C
index 8cebf7d..9e0e9b8 100644
--- a/spyview/ImageWindow.C
+++ b/spyview/ImageWindow.C
@@ -1636,6 +1636,8 @@ void ImageWindow::runQueue()
             id.cbc(op->parameters[0].value, op->parameters[1].value, 0, 1, op->parameters[2].value, op->parameters[3].value);
 	  else if (op->name == "power")
 	    id.gamma(op->parameters[0].value,op->parameters[1].value);
+	  else if (op->name == "power2")
+	    id.power2(op->parameters[0].value);
 	  else if (op->name == "scale data")
 	    id.scale(op->parameters[0].value);
 	  else if (op->name == "even odd")
diff --git a/spyview/spyview.C b/spyview/spyview.C
index 5216a5d..2f3ea85 100644
--- a/spyview/spyview.C
+++ b/spyview/spyview.C
@@ -522,11 +522,15 @@ int main(int argc, char **argv)
   gradmag.addParameter("Axis Bias [0-1.0]",0.5);
   Define_Image_Operation(&gradmag);
 
-  Image_Operation gamma("power","y = x^p, p<0 & abs(x)<eps => truncate x, y<0 & p not int => set y=0"); // a better name
+  Image_Operation gamma("power","y = data^p. If p<0 & abs(data)<eps => truncate x to avoid 1/0. If data<0 & p not int => set data=0 to avoid complex numbers"); // a better name
   gamma.addParameter("Power", 0.5);
   gamma.addParameter("Epsilon", 1e-20);
   Define_Image_Operation(&gamma);
 
+  Image_Operation power2("power2","y = b^data");
+  power2.addParameter("Base (b)", 10);
+  Define_Image_Operation(&power2);
+
   Define_Image_Operation(new Image_Operation("norm lbl","Stretch the contrast of each line to full scale"));
   Define_Image_Operation(new Image_Operation("norm cbc","Stretch the contrast of each column to full scale"));
 
-- 
2.25.1