first re-commit.

pigpio-master/EXAMPLES/CPP/ROTARY_ENCODER/rotary_encoder.hpp

@@ -0,0 +1,35 @@
+#ifndef ROTARY_ENCODER_HPP
+#define ROTARY_ENCODER_HPP
+
+#include <stdint.h>
+
+typedef void (*re_decoderCB_t)(int);
+
+class re_decoder
+{
+   int mygpioA, mygpioB, levA, levB, lastGpio;
+
+   re_decoderCB_t mycallback;
+
+   void _pulse(int gpio, int level, uint32_t tick);
+
+   /* Need a static callback to link with C. */
+   static void _pulseEx(int gpio, int level, uint32_t tick, void *user);
+
+
+   public:
+
+   re_decoder(int gpioA, int gpioB, re_decoderCB_t callback);
+   /*
+      This function establishes a rotary encoder on gpioA and gpioB.
+
+      When the encoder is turned the callback function is called.
+   */
+
+   void re_cancel(void);
+   /*
+      This function releases the resources used by the decoder.
+   */
+};
+
+#endif