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-rw-r--r--Build/source/libs/xpdf/goo/FixedPoint.cc95
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diff --git a/Build/source/libs/xpdf/goo/FixedPoint.cc b/Build/source/libs/xpdf/goo/FixedPoint.cc
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+++ b/Build/source/libs/xpdf/goo/FixedPoint.cc
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+//========================================================================
+//
+// FixedPoint.cc
+//
+// Fixed point type, with C++ operators.
+//
+// Copyright 2004 Glyph & Cog, LLC
+//
+//========================================================================
+
+#include <aconf.h>
+
+#if USE_FIXEDPOINT
+
+#ifdef USE_GCC_PRAGMAS
+#pragma implementation
+#endif
+
+#include "FixedPoint.h"
+
+FixedPoint FixedPoint::sqrt(FixedPoint x) {
+ FixedPoint y0, y1, z;
+
+ if (x.val <= 0) {
+ y1.val = 0;
+ } else {
+ y1.val = x.val >> 1;
+ do {
+ y0.val = y1.val;
+ z = x / y0;
+ y1.val = (y0.val + z.val) >> 1;
+ } while (::abs(y0.val - y1.val) > 1);
+ }
+ return y1;
+}
+
+//~ this is not very accurate
+FixedPoint FixedPoint::pow(FixedPoint x, FixedPoint y) {
+ FixedPoint t, t2, lnx0, lnx, z0, z;
+ int d, i;
+
+ if (y.val <= 0) {
+ z.val = 0;
+ } else {
+ // y * ln(x)
+ t = (x - 1) / (x + 1);
+ t2 = t * t;
+ d = 1;
+ lnx = 0;
+ do {
+ lnx0 = lnx;
+ lnx += t / d;
+ t *= t2;
+ d += 2;
+ } while (::abs(lnx.val - lnx0.val) > 2);
+ lnx.val <<= 1;
+ t = y * lnx;
+ // exp(y * ln(x))
+ t2 = t;
+ d = 1;
+ i = 1;
+ z = 1;
+ do {
+ z0 = z;
+ z += t2 / d;
+ t2 *= t;
+ ++i;
+ d *= i;
+ } while (::abs(z.val - z0.val) > 2 && d < (1 << fixptShift));
+ }
+ return z;
+}
+
+int FixedPoint::mul(int x, int y) {
+#if 1 //~tmp
+ return ((FixPtInt64)x * y) >> fixptShift;
+#else
+ int ah0, ah, bh, al, bl;
+ ah0 = x & fixptMaskH;
+ ah = x >> fixptShift;
+ al = x - ah0;
+ bh = y >> fixptShift;
+ bl = y - (bh << fixptShift);
+ return ah0 * bh + ah * bl + al * bh + ((al * bl) >> fixptShift);
+#endif
+}
+
+int FixedPoint::div(int x, int y) {
+#if 1 //~tmp
+ return ((FixPtInt64)x << fixptShift) / y;
+#else
+#endif
+}
+
+#endif // USE_FIXEDPOINT