1 files changed, 111 insertions, 0 deletions
diff --git a/src/util/fixed_point.h b/src/util/fixed_point.h
new file mode 100644
index 0000000..44174d0
--- /dev/null
+++ b/src/util/fixed_point.h
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Util::FixedPoint - fixed point type
+ *
+ * Authors:
+ *   Jasper van de Gronde <th.v.d.gronde@hccnet.net>
+ *
+ * Copyright (C) 2006 Jasper van de Gronde
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_UTIL_FIXED_POINT_H
+#define SEEN_INKSCAPE_UTIL_FIXED_POINT_H
+
+#include <cmath>
+#include <algorithm>
+#include <limits>
+
+namespace Inkscape {
+
+namespace Util {
+
+template <typename T, unsigned int precision>
+class FixedPoint {
+public:
+    FixedPoint() = default;
+    FixedPoint(const FixedPoint& value) : v(value.v) {}
+    FixedPoint(char value) : v(static_cast<T>(value)<<precision) {}
+    FixedPoint(unsigned char value) : v(static_cast<T>(value)<<precision) {}
+    FixedPoint(short value) : v(static_cast<T>(value)<<precision) {}
+    FixedPoint(unsigned short value) : v(static_cast<T>(value)<<precision) {}
+    FixedPoint(int value) : v(static_cast<T>(value)<<precision) {}
+    FixedPoint(unsigned int value) : v(static_cast<T>(value)<<precision) {}
+    FixedPoint(double value) : v(static_cast<T>(floor(value*(1<<precision)))) {}
+
+    FixedPoint& operator+=(FixedPoint val) { v += val.v; return *this; }
+    FixedPoint& operator-=(FixedPoint val) { v -= val.v; return *this; }
+    FixedPoint& operator*=(FixedPoint val) {
+        const unsigned int half_size = 8*sizeof(T)/2;
+        const T al = v&((1<<half_size)-1), bl = val.v&((1<<half_size)-1);
+        const T ah = v>>half_size, bh = val.v>>half_size;
+        v = static_cast<unsigned int>(al*bl)>>precision;
+        if ( half_size >= precision ) {
+            v += ((al*bh)+(ah*bl)+((ah*bh)<<half_size))<<(half_size-precision);
+        } else {
+            v += ((al*bh)+(ah*bl))>>(precision-half_size);
+            v += (ah*bh)<<(2*half_size-precision);
+        }
+        return *this;
+    }
+
+    FixedPoint& operator*=(char val) { v *= val; return *this; }
+    FixedPoint& operator*=(unsigned char val) { v *= val; return *this; }
+    FixedPoint& operator*=(short val) { v *= val; return *this; }
+    FixedPoint& operator*=(unsigned short val) { v *= val; return *this; }
+    FixedPoint& operator*=(int val) { v *= val; return *this; }
+    FixedPoint& operator*=(unsigned int val) { v *= val; return *this; }
+
+    FixedPoint operator+(FixedPoint val) const { FixedPoint r(*this); return r+=val; }
+    FixedPoint operator-(FixedPoint val) const { FixedPoint r(*this); return r-=val; }
+    FixedPoint operator*(FixedPoint val) const { FixedPoint r(*this); return r*=val; }
+
+    FixedPoint operator*(char val) const { FixedPoint r(*this); return r*=val; }
+    FixedPoint operator*(unsigned char val) const { FixedPoint r(*this); return r*=val; }
+    FixedPoint operator*(short val) const { FixedPoint r(*this); return r*=val; }
+    FixedPoint operator*(unsigned short val) const { FixedPoint r(*this); return r*=val; }
+    FixedPoint operator*(int val) const { FixedPoint r(*this); return r*=val; }
+    FixedPoint operator*(unsigned int val) const { FixedPoint r(*this); return r*=val; }
+
+    float operator*(float val) const { return static_cast<float>(*this)*val; }
+    double operator*(double val) const { return static_cast<double>(*this)*val; }
+
+    operator char() const { return v>>precision; }
+    operator unsigned char() const { return v>>precision; }
+    operator short() const { return v>>precision; }
+    operator unsigned short() const { return v>>precision; }
+    operator int() const { return v>>precision; }
+    operator unsigned int() const { return v>>precision; }
+
+    operator float() const { return ldexpf(v,-precision); }
+    operator double() const { return ldexp(v,-precision); }
+private:
+    T v;
+};
+
+template<typename T, unsigned int precision> FixedPoint<T,precision> operator *(char a, FixedPoint<T,precision> b) { return b*=a; }
+template<typename T, unsigned int precision> FixedPoint<T,precision> operator *(unsigned char a, FixedPoint<T,precision> b) { return b*=a; }
+template<typename T, unsigned int precision> FixedPoint<T,precision> operator *(short a, FixedPoint<T,precision> b) { return b*=a; }
+template<typename T, unsigned int precision> FixedPoint<T,precision> operator *(unsigned short a, FixedPoint<T,precision> b) { return b*=a; }
+template<typename T, unsigned int precision> FixedPoint<T,precision> operator *(int a, FixedPoint<T,precision> b) { return b*=a; }
+template<typename T, unsigned int precision> FixedPoint<T,precision> operator *(unsigned int a, FixedPoint<T,precision> b) { return b*=a; }
+
+template<typename T, unsigned int precision> float operator *(float a, FixedPoint<T,precision> b) { return b*a; }
+template<typename T, unsigned int precision> double operator *(double a, FixedPoint<T,precision> b) { return b*a; }
+
+}
+
+}
+
+#endif
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :