Import Wiring math functions

teensy4/WMath.cpp

+/*
+  Part of the Wiring project - http://wiring.org.co
+  Copyright (c) 2004-06 Hernando Barragan
+  Modified 13 August 2006, David A. Mellis for Arduino - http://www.arduino.cc/
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General
+  Public License along with this library; if not, write to the
+  Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+  Boston, MA  02111-1307  USA
+*/
+
+#include <stdint.h>
+
+static uint32_t seed;
+
+void randomSeed(uint32_t newseed)
+{
+	if (newseed > 0) seed = newseed;
+}
+
+void srandom(unsigned int newseed)
+{
+	seed = newseed;
+}
+
+int32_t random(void)
+{
+	int32_t hi, lo, x;
+
+	// the algorithm used in avr-libc 1.6.4
+	x = seed;
+	if (x == 0) x = 123459876;
+	hi = x / 127773;
+	lo = x % 127773;
+	x = 16807 * lo - 2836 * hi;
+	if (x < 0) x += 0x7FFFFFFF;
+	seed = x;
+	return x;
+}
+
+uint32_t random(uint32_t howbig)
+{
+	if (howbig == 0) return 0;
+	return random() % howbig;
+}
+
+int32_t random(int32_t howsmall, int32_t howbig)
+{
+	if (howsmall >= howbig) return howsmall;
+	int32_t diff = howbig - howsmall;
+	return random(diff) + howsmall;
+}
+
+unsigned int makeWord(unsigned int w) { return w; }
+unsigned int makeWord(unsigned char h, unsigned char l) { return (h << 8) | l; }
+