+ 0.1.02 fastMap first stable version

+ does as much math as possible in advance + 3 versions of constrained map

Author: RobTillaart

libraries/fastMap/examples/fastMapper/fastMapper.ino

@@ -0,0 +1,70 @@
+//
+// FILE: fastMapper.ino
+// AUTHOR: Rob Tillaart
+// VERSION: 0.1.00
+// PURPOSE: demo of a faster mapper function
+// DATE: 2014-11-02
+// URL:
+//
+// Released to the public domain
+//
+
+#include "fastMap.h"
+
+uint32_t start;
+uint32_t stop;
+uint32_t reference;
+
+volatile long zz = 3000, yy = 20000;
+volatile float x;
+
+fastmap mapper;
+
+void setup()
+{
+ Serial.begin(115200);
+ Serial.print("Start fastmap demo\nlib version: ");
+ Serial.println(FASTMAP_LIB_VERSION);
+ Serial.println();
+
+ // Get a non optimizable value;
+ int z = analogRead(A0);
+
+ // REFERENCE
+ start = micros();
+ for (int i = 0; i < 10000; i++)
+ {
+ x = map(z, 0, 1023, yy, zz);
+ }
+ stop = micros();
+ reference = stop-start;
+ Serial.println(reference);
+ Serial.print(z);
+ Serial.print(" -> ");
+ Serial.println(x);
+ Serial.println();
+
+ // FASTMAP
+ mapper.init(0, 1023, yy, zz);
+ start = micros();
+ for (int i = 0; i < 10000; i++)
+ {
+ x = mapper.map(z);
+ }
+ stop = micros();
+ Serial.println(stop-start);
+ Serial.print(z);
+ Serial.print(" -> ");
+ Serial.println(x);
+
+ // GAIN
+ Serial.print("Performance factor: ");
+ Serial.println(reference/(stop-start));
+}
+
+void loop()
+{
+}
+//
+// END OF FILE
+//

libraries/fastMap/fastMap.cpp

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+//
+// FILE: fastMap.cpp
+// AUTHOR: Rob Tillaart
+// VERSION: 0.1.02
+// PURPOSE: class implementation of map function - library for Arduino
+// URL: http://forum.arduino.cc/index.php?topic=276194
+//
+// HISTORY:
+// 0.1.02 squized the code (first public version)
+// 0.1.01 refactor
+// 0.1.00 initial version
+//
+
+#include "fastMap.h"
+
+/////////////////////////////////////////////////////
+//
+// PUBLIC
+//
+
+void fastmap::init(float in_min, float in_max, float out_min, float out_max)
+{
+ _in_min = in_min;
+ _in_max = in_max;
+ _out_min = out_min;
+ _out_max = out_max;
+ _factor = (out_max - out_min)/(in_max - in_min);
+ _base = out_min - in_min * _factor;
+ // Serial.println(_in_min);
+ // Serial.println(_in_max);
+ // Serial.println(_out_min);
+ // Serial.println(_out_max);
+ // Serial.println(_factor);
+}
+ 
+float fastmap::constrainedMap(float value)
+{
+ if (value <= _in_min) return _out_min;
+ if (value >= _in_max) return _out_max;
+ return this->map(value);
+}
+
+float fastmap::lowerConstrainedMap(float value)
+{
+ if (value <= _in_min) return _out_min;
+ return this->map(value);
+}
+
+float fastmap::upperConstrainedMap(float value)
+{
+ if (value >= _in_max) return _out_max;
+ return this->map(value);
+}
+//
+// END OF FILE
+//

libraries/fastMap/fastMap.h

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+//
+// FILE: fastMap.h
+// AUTHOR: Rob Tillaart
+// VERSION: 0.1.02
+// PURPOSE: class implementation of map function - library for Arduino
+// URL: http://forum.arduino.cc/index.php?topic=276194
+//
+// HISTORY:
+// see fastMap.cpp file
+//
+
+#ifndef fastMap_h
+#define fastMap_h
+
+#if ARDUINO < 100
+#include <WProgram.h>
+#else
+#include <Arduino.h>
+#endif
+
+#define FASTMAP_LIB_VERSION "0.1.02"
+
+#define USE_CONSTRAINED_MAP
+
+class fastmap
+{
+public:
+ void init(float in_min, float in_max, float out_min, float out_max);
+
+ float inline map(float value) { return _base + value * _factor; }
+ float constrainedMap(float value);
+ float lowerConstrainedMap(float value);
+ float upperConstrainedMap(float value);
+
+private:
+ float _in_min, _in_max, _out_min, _out_max;
+ float _factor, _base;
+};
+
+#endif
+//
+// END OF FILE
+//