From 581ef48ba8f4dd765afc7378574b9bdda2f01e1a Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Fri, 8 Mar 2013 02:52:50 +0100
Subject: [PATCH] begin ecmult

---
 ecmult.h      | 43 +++++++++++++++++++++++++++++++++++++++++++
 secp256k1.cpp |  1 +
 2 files changed, 44 insertions(+)
 create mode 100644 ecmult.h

diff --git a/ecmult.h b/ecmult.h
new file mode 100644
index 0000000..ce43b0e
--- /dev/null
+++ b/ecmult.h
@@ -0,0 +1,43 @@
+#ifndef _SECP256K1_ECMULT_
+#define _SECP256K1_ECMULT_
+
+#include "group.h"
+#include "scalar.h"
+
+namespace secp256k1 {
+
+template<typename G, int W> class WNAFPrecomp {
+private:
+    G pre[1 << (W-2)];
+
+public:
+    WNAFPrecomp(G &base) {
+        pre[0] = base;
+        GroupElemJac x = base;
+        GroupElemJac d; d.SetDouble(x);
+        for (int i=1; i<(1 << (W-2)); i++) {
+            x.SetAdd(d,pre[i-1]);
+            pre[i] = x;
+        }
+    }
+
+    void Get(G &out, int exp) {
+        assert((exp & 1) == 1);
+        assert(exp >= -((1 << (W-1)) - 1));
+        assert(exp <=  ((1 << (W-1)) - 1));
+        if (exp > 0) {
+            out = pre[(exp-1)/2];
+        } else {
+            out.SetNeg(pre[(1-exp)/2]);
+        }
+    }
+};
+
+class WNAF {
+private:
+
+};
+
+}
+
+#endif
diff --git a/secp256k1.cpp b/secp256k1.cpp
index 2e18196..dfdef52 100644
--- a/secp256k1.cpp
+++ b/secp256k1.cpp
@@ -5,6 +5,7 @@
 #include "scalar.h"
 #include "field.h"
 #include "group.h"
+#include "ecmult.h"
 
 using namespace secp256k1;