andrewm@66: /**
andrewm@66:  *  @file
andrewm@66:  *  @brief Wiring-inspired utility functions and macros
andrewm@0:  *
andrewm@66:  *  Macros and functions for I/O and data processing taking after the Wiring
andrewm@66:  *  (Arduino) language. This code began as part of the Hackable Instruments
andrewm@66:  *  project (EPSRC) at Queen Mary University of London, 2013-14.
andrewm@66:  *
andrewm@66:  *  (c) 2014-15 Andrew McPherson, Victor Zappi and Giulio Moro,
andrewm@66:  *  Queen Mary University of London
andrewm@0:  */
andrewm@0: 
andrewm@0: #ifndef UTILITIES_H_
andrewm@0: #define UTILITIES_H_
andrewm@0: 
giuliomoro@301: #include "Bela.h"
andrewm@45: 
andrewm@95: /**
andrewm@95:  * \defgroup iofunctions I/O functions and constants
andrewm@95:  *
andrewm@95:  * These functions and macros are used for audio, analog and digital I/O. All the
giuliomoro@301:  * I/O functions require the BelaContext data structure from render() to be passed
andrewm@95:  * in. This means that these functions are, by design, \b only usable from within
andrewm@95:  * the rendering thread.
andrewm@95:  * 
andrewm@95:  * The naming conventions are loosely derived from the Arduino environment, and the
andrewm@95:  * syntax is similar. Unlike Arduino, the I/O functions require the frame number at which
andrewm@95:  * the read or write should take place, since all I/O happens synchronously with the
andrewm@95:  * audio clock.
andrewm@95:  *
andrewm@95:  * @{
andrewm@95:  */
andrewm@95: 
giuliomoro@187: #ifndef INPUT
giuliomoro@187: 	#define INPUT 0x0
giuliomoro@187: #endif /* INPUT */
andrewm@72: 
giuliomoro@187: #ifndef OUTPUT
giuliomoro@187: 	#define OUTPUT 0x1
giuliomoro@187: #endif /* OUTPUT */
andrewm@72: 
andrewm@95: /** @} */
andrewm@95: 
andrewm@95: /**
andrewm@95:  * \ingroup wiring
andrewm@95:  *
andrewm@95:  * @{
andrewm@95:  */
andrewm@95: 
andrewm@66: /// Set the given bit in \c word to 1.
andrewm@45: #define setBit(word,bit) 			((word) | (1 << (bit)))
andrewm@66: 
andrewm@66: /// Clear the given bit in \c word to 0.
andrewm@45: #define clearBit(word,bit) 			((word) &~ (1 << (bit)))
andrewm@66: 
andrewm@66: /// Check if the given bit in \c word is 1 (returns nonzero) or 0 (returns zero).
andrewm@45: #define getBit(word,bit) 			(((word) >> (bit)) & 1)
andrewm@66: 
andrewm@66: /// Set/clear the given bit in \c word to \c value.
andrewm@45: #define changeBit(word,bit,value) 	((clearBit((word),(bit))) | ((value) << (bit)))
andrewm@45: 
andrewm@95: /** @} */
andrewm@95: 
andrewm@95: /**
andrewm@95:  * \ingroup iofunctions
andrewm@95:  *
andrewm@95:  * @{
andrewm@95:  */
andrewm@95: 
andrewm@45: #if 1
andrewm@56: // Note: pinMode(), analogWrite() and digitalWrite() should be able to be called from setup()
andrewm@56: // Likewise, thread launch should be able to be called from setup()
andrewm@45: // Also, make volume change functions callable from render() thread -- as an aux task?
andrewm@45: 
andrewm@68: /**
giuliomoro@179:  * \brief Read an audio input, specifying the frame number (when to read) and the channel.
giuliomoro@179:  *
giuliomoro@179:  * This function returns the value of an audio input, at the time indicated by \c frame.
giuliomoro@179:  * The returned value ranges from -1 to 1.
giuliomoro@179:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
giuliomoro@179:  * \param frame Which frame (i.e. what time) to read the audio input. Valid values range
giuliomoro@179:  * from 0 to (context->audioFrames - 1).
giuliomoro@179:  * \param channel Which audio input to read. Valid values are between 0 and
giuliomoro@179:  * (context->audioChannels - 1), typically 0 to 1 by default.
giuliomoro@179:  * \return Value of the analog input, range  to 1.
giuliomoro@179:  */
giuliomoro@301: static inline float audioReadFrame(BelaContext *context, int frame, int channel);
giuliomoro@179: 
giuliomoro@179: /**
giuliomoro@179:  * \brief Write an audio output, specifying the frame number (when to write) and the channel.
giuliomoro@179:  *
giuliomoro@179:  * This function sets the value of an audio output, at the time indicated by \c frame. Valid
giuliomoro@179:  * values are between -1 and 1.
giuliomoro@179:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
giuliomoro@179:  * \param frame Which frame (i.e. what time) to write the audio output. Valid values range
giuliomoro@179:  * from 0 to (context->audioFrames - 1).
giuliomoro@179:  * \param channel Which analog output to write. Valid values are between 0 and
giuliomoro@179:  * (context->audioChannels - 1), typically 0 to 1 by default.
giuliomoro@179:  * \param value Value to write to the output, range -1 to 1.
giuliomoro@179:  */
giuliomoro@301: static inline void audioWriteFrame(BelaContext *context, int frame, int channel, float value);
giuliomoro@179: 
giuliomoro@179: /**
andrewm@68:  * \brief Read an analog input, specifying the frame number (when to read) and the channel.
andrewm@68:  *
andrewm@68:  * This function returns the value of an analog input, at the time indicated by \c frame.
andrewm@68:  * The returned value ranges from 0 to 1, corresponding to a voltage range of 0 to 4.096V.
andrewm@68:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
andrewm@68:  * \param frame Which frame (i.e. what time) to read the analog input. Valid values range
andrewm@68:  * from 0 to (context->analogFrames - 1).
andrewm@68:  * \param channel Which analog input to read. Valid values are between 0 and
andrewm@68:  * (context->analogChannels - 1), typically 0 to 7 by default.
andrewm@68:  * \return Value of the analog input, range 0 to 1.
andrewm@68:  */
giuliomoro@301: static inline float analogReadFrame(BelaContext *context, int frame, int channel);
andrewm@68: 
andrewm@68: /**
andrewm@68:  * \brief Write an analog output, specifying the frame number (when to write) and the channel.
andrewm@68:  *
andrewm@68:  * This function sets the value of an analog output, at the time indicated by \c frame. Valid
andrewm@68:  * values are between 0 and 1, corresponding to the range 0 to 5V.
andrewm@68:  *
andrewm@68:  * The value written will persist for all future frames if BEAGLERT_FLAG_ANALOG_OUTPUTS_PERSIST
andrewm@68:  * is set in context->flags. This is the default behaviour.
andrewm@68:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
andrewm@68:  * \param frame Which frame (i.e. what time) to write the analog output. Valid values range
andrewm@68:  * from 0 to (context->analogFrames - 1).
andrewm@68:  * \param channel Which analog output to write. Valid values are between 0 and
andrewm@68:  * (context->analogChannels - 1), typically 0 to 7 by default.
andrewm@68:  * \param value Value to write to the output, range 0 to 1.
andrewm@68:  */
giuliomoro@301: static inline void analogWriteFrame(BelaContext *context, int frame, int channel, float value);
andrewm@68: 
andrewm@68: /**
andrewm@68:  * \brief Write an analog output, specifying the frame number (when to write) and the channel.
andrewm@68:  *
andrewm@68:  * This function sets the value of an analog output, at the time indicated by \c frame. Valid
andrewm@68:  * values are between 0 and 1, corresponding to the range 0 to 5V.
andrewm@68:  *
andrewm@68:  * Unlike analogWriteFrame(), the value written will affect \b only the frame specified, with
andrewm@72:  * future values unchanged. This is faster than analogWriteFrame() so is better suited
andrewm@68:  * to applications where every frame will be written to a different value. If
andrewm@68:  * BEAGLERT_FLAG_ANALOG_OUTPUTS_PERSIST is not set within context->flags, then
andrewm@68:  * analogWriteFrameOnce() and analogWriteFrame() are equivalent.
andrewm@68:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
andrewm@68:  * \param frame Which frame (i.e. what time) to write the analog output. Valid values range
andrewm@68:  * from 0 to (context->analogFrames - 1).
andrewm@68:  * \param channel Which analog output to write. Valid values are between 0 and
andrewm@68:  * (context->analogChannels - 1), typically 0 to 7 by default.
andrewm@68:  * \param value Value to write to the output, range 0 to 1.
andrewm@68:  */
giuliomoro@301: static inline void analogWriteFrameOnce(BelaContext *context, int frame, int channel, float value);
andrewm@45: 
andrewm@72: /**
andrewm@72:  * \brief Read a digital input, specifying the frame number (when to read) and the pin.
andrewm@72:  *
andrewm@72:  * This function returns the value of a digital input, at the time indicated by \c frame.
andrewm@72:  * The value is 0 if the pin is low, and nonzero if the pin is high (3.3V).
andrewm@72:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
andrewm@72:  * \param frame Which frame (i.e. what time) to read the digital input. Valid values range
andrewm@72:  * from 0 to (context->digitalFrames - 1).
andrewm@72:  * \param channel Which digital pin to read. 16 pins across the P8 and P9 headers of the
andrewm@72:  * BeagleBone Black are available. See the constants P8_xx and P9_xx defined in
andrewm@72:  * digital_gpio_mapping.h.
andrewm@72:  * \return Value of the digital input.
andrewm@72:  */
giuliomoro@301: static inline int digitalReadFrame(BelaContext *context, int frame, int channel);
andrewm@72: 
andrewm@72: /**
andrewm@72:  * \brief Write a digital output, specifying the frame number (when to write) and the pin.
andrewm@72:  *
andrewm@72:  * This function sets the value of a digital output, at the time indicated by \c frame.
andrewm@72:  * A value of 0 sets the pin low; any other value sets the pin high (3.3V).
andrewm@72:  *
andrewm@72:  * The value written will persist for all future frames.
andrewm@72:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
andrewm@72:  * \param frame Which frame (i.e. what time) to write the digital output. Valid values range
andrewm@72:  * from 0 to (context->digitalFrames - 1).
andrewm@72:  * \param channel Which digital output to write. 16 pins across the P8 and P9 headers of the
andrewm@72:  * BeagleBone Black are available. See the constants P8_xx and P9_xx defined in
andrewm@72:  * digital_gpio_mapping.h.
andrewm@72:  * \param value Value to write to the output.
andrewm@72:  */
giuliomoro@301: static inline void digitalWriteFrame(BelaContext *context, int frame, int channel, int value);
andrewm@72: 
andrewm@72: /**
andrewm@72:  * \brief Write a digital output, specifying the frame number (when to write) and the pin.
andrewm@72:  *
andrewm@72:  * This function sets the value of a digital output, at the time indicated by \c frame.
andrewm@72:  * A value of 0 sets the pin low; any other value sets the pin high (3.3V).
andrewm@72:  *
andrewm@72:  * Unlike digitalWriteFrame(), the value written will affect \b only the frame specified, with
andrewm@72:  * future values unchanged. This is faster than digitalWriteFrame() so is better suited
andrewm@72:  * to applications where every frame will be written to a different value.
andrewm@72:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
andrewm@72:  * \param frame Which frame (i.e. what time) to write the digital output. Valid values range
andrewm@72:  * from 0 to (context->digitalFrames - 1).
andrewm@72:  * \param channel Which digital output to write. 16 pins across the P8 and P9 headers of the
andrewm@72:  * BeagleBone Black are available. See the constants P8_xx and P9_xx defined in
andrewm@72:  * digital_gpio_mapping.h.
andrewm@72:  * \param value Value to write to the output.
andrewm@72:  */
giuliomoro@301: static inline void digitalWriteFrameOnce(BelaContext *context, int frame, int channel, int value);
andrewm@45: 
andrewm@72: /**
andrewm@72:  * \brief Set the direction of a digital pin to input or output.
andrewm@72:  *
andrewm@72:  * This function sets the direction of a digital pin, at the time indicated by \c frame.
andrewm@72:  * Valid values are \c INPUT and \c OUTPUT. All pins begin as inputs by default.
andrewm@72:  *
andrewm@72:  * The value written will persist for all future frames.
andrewm@72:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
andrewm@72:  * \param frame Which frame (i.e. what time) to set the pin direction. Valid values range
andrewm@72:  * from 0 to (context->digitalFrames - 1).
andrewm@72:  * \param channel Which digital output to write. 16 pins across the P8 and P9 headers of the
andrewm@72:  * BeagleBone Black are available. See the constants P8_xx and P9_xx defined in
andrewm@72:  * digital_gpio_mapping.h.
andrewm@72:  * \param value Direction of the pin (\c INPUT or \c OUTPUT).
andrewm@72:  */
giuliomoro@301: static inline void pinModeFrame(BelaContext *context, int frame, int channel, int mode);
andrewm@72: 
andrewm@72: /**
andrewm@72:  * \brief Set the direction of a digital pin to input or output.
andrewm@72:  *
andrewm@72:  * This function sets the direction of a digital pin, at the time indicated by \c frame.
andrewm@72:  * Valid values are \c INPUT and \c OUTPUT. All pins begin as inputs by default.
andrewm@72:  *
andrewm@72:  * The value written will affect only the specified frame.
andrewm@72:  *
giuliomoro@301:  * \param context The I/O data structure which is passed by Bela to render().
andrewm@72:  * \param frame Which frame (i.e. what time) to set the pin direction. Valid values range
andrewm@72:  * from 0 to (context->digitalFrames - 1).
andrewm@72:  * \param channel Which digital output to write. 16 pins across the P8 and P9 headers of the
andrewm@72:  * BeagleBone Black are available. See the constants P8_xx and P9_xx defined in
andrewm@72:  * digital_gpio_mapping.h.
andrewm@72:  * \param value Direction of the pin (\c INPUT or \c OUTPUT).
andrewm@72:  */
giuliomoro@301: static inline void pinModeFrameOnce(BelaContext *context, int frame, int channel, int mode);
andrewm@45: 
andrewm@95: /** @} */
andrewm@95: 
andrewm@45: #else
andrewm@13: 
giuliomoro@19: // Macros for accessing the analog values: usable _only_ within render()
andrewm@5: 
giuliomoro@19: // Read an Analog input from input pin p at frame f
giuliomoro@23: #define analogRead(p, f) (analogIn[(f)*gNumAnalogChannels + (p)])
giuliomoro@19: // Write an Analog output frame at output pin p, frame f, to value v
giuliomoro@23: #define analogWriteFrame(p, f, v) (analogOut[(f)*gNumAnalogChannels + (p)] = (v))
giuliomoro@23: #define analogWrite(pin, frame, value) \
giuliomoro@18: (({do {\
giuliomoro@19: 	for (int _privateI=(frame); _privateI<numAnalogFrames; _privateI++){ \
giuliomoro@23: 		analogWriteFrame(pin,_privateI,value); \
giuliomoro@18: 	}\
giuliomoro@18: 	} while (0);}),(void)0)\
andrewm@5: 
andrewm@45: 
giuliomoro@19: //digital API:
giuliomoro@33: #define setDigitalDirectionFrame(pin,frame,direction) digital[(frame)]=changeBit(digital[(frame)],(pin),(direction)),void(0)
giuliomoro@33: #define setDigitalDirection(pin,frame,direction)\
giuliomoro@33: 		(({do {\
giuliomoro@33: 			for(int _privateI=(frame); _privateI<numDigitalFrames; _privateI++)\
giuliomoro@33: 				setDigitalDirectionFrame(pin,_privateI,direction);\
giuliomoro@33: 			} while (0);}), (void)0)
giuliomoro@19: #define digitalWriteAll(frame,value) digital[(frame)]=0xffff0000*(!(!value));
giuliomoro@16: //sets the bit in the high word, clears the bit in the low word (just in case the direction was not previously set)
giuliomoro@19: #define digitalWriteFrame(pin, frame, value) digital[(frame)]=( changeBit(digital[(frame)], (pin+16), (value)) & (0xffffffff-(1<<(pin))) ) //could have been done with two subsequent assignments
giuliomoro@18: #define digitalWrite(pin, frame, value) \
giuliomoro@18: 	(({do {\
giuliomoro@33: 		for (int _privateI=(frame); _privateI<numDigitalFrames; _privateI++) \
giuliomoro@18: 			digitalWriteFrame(pin,_privateI,value); \
giuliomoro@18: 		} while (0);}),(void)0)\
giuliomoro@18: 
giuliomoro@19: #define digitalRead(pin, frame) ( getBit(digital[(frame)], pin+16) )
giuliomoro@16: 
andrewm@45: #endif
andrewm@45: 
andrewm@66: /**
andrewm@95:  * \defgroup wiring Wiring language support
andrewm@95:  *
andrewm@95:  * These are functions found in the Wiring (Arduino) language which are not directly
andrewm@95:  * related to I/O but are provided as a convenience.
andrewm@95:  *
andrewm@95:  * @{
andrewm@95:  */
andrewm@95: 
andrewm@95: /**
andrewm@66:  * \brief Linearly rescale a number from one range of values to another.
andrewm@66:  *
andrewm@66:  * This function linearly scales values of \c x such that the range in_min to
andrewm@66:  * in_max at the input corresponds to the range out_min to out_max
andrewm@66:  * at the output. Values outside this range are extrapolated.
andrewm@66:  *
andrewm@66:  * This function behaves identically to the function of the same name in Processing. It
andrewm@66:  * is also similar to the corresponding function in Arduino, except that it supports floating
andrewm@66:  * point values.
andrewm@66:  *
andrewm@66:  * \param x Input value to be mapped.
andrewm@66:  * \param in_min Lower bound of the input range.
andrewm@66:  * \param in_max Upper bound of the input range.
andrewm@66:  * \param out_min Lower bound of the output range.
andrewm@66:  * \param out_max Upper bound of the output range.
andrewm@66:  * \return Rescaled value.
andrewm@66:  */
giuliomoro@187: static inline float map(float x, float in_min, float in_max, float out_min, float out_max);
andrewm@66: 
andrewm@66: /**
andrewm@66:  * \brief Constrain a number to stay within a given range.
andrewm@66:  *
andrewm@66:  * This function constrains \c x to remain within the range min_val to
andrewm@66:  * max_val. Values of \c x outside this range are clipped to the edges
andrewm@66:  * of the range.
andrewm@66:  *
andrewm@66:  * This function behaves identically to the function of the same name in Processing. It
andrewm@66:  * is also similar to the corresponding function in Arduino, except that it supports floating
andrewm@66:  * point values.
andrewm@66:  *
andrewm@66:  * \param x Input value to be constrained.
andrewm@66:  * \param min_val Minimum possible value.
andrewm@66:  * \param max_val Maximum possible value.
andrewm@66:  * \return Constrained value.
andrewm@66:  */
giuliomoro@187: static inline float constrain(float x, float min_val, float max_val);
andrewm@0: 
andrewm@95: /** @} */
giuliomoro@187: // audioReadFrame()
giuliomoro@187: //
giuliomoro@187: // Returns the value of the given audio input at the given frame number.
giuliomoro@301: static inline float audioReadFrame(BelaContext *context, int frame, int channel) {
giuliomoro@187: 	return context->audioIn[frame * context->audioChannels + channel];
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // audioWriteFrame()
giuliomoro@187: //
giuliomoro@187: // Sets a given audio output channel to a value for the current frame
giuliomoro@301: static inline void audioWriteFrame(BelaContext *context, int frame, int channel, float value) {
giuliomoro@187: 	context->audioOut[frame * context->audioChannels + channel] = value;
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // analogReadFrame()
giuliomoro@187: //
giuliomoro@187: // Returns the value of the given analog input at the given frame number.
giuliomoro@301: static inline float analogReadFrame(BelaContext *context, int frame, int channel) {
giuliomoro@187: 	return context->analogIn[frame * context->analogChannels + channel];
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // analogWriteFrame()
giuliomoro@187: //
giuliomoro@187: // Sets a given analog output channel to a value for the current frame and, if persistent outputs are
giuliomoro@187: // enabled, for all subsequent frames
giuliomoro@301: static inline void analogWriteFrame(BelaContext *context, int frame, int channel, float value) {
giuliomoro@187: 	if(context->flags & BEAGLERT_FLAG_ANALOG_OUTPUTS_PERSIST) {
giuliomoro@187: 		for(unsigned int f = frame; f < context->analogFrames; f++)
giuliomoro@187: 			context->analogOut[frame * context->analogChannels + channel] = value;
giuliomoro@187: 	}
giuliomoro@187: 	else
giuliomoro@187: 		context->analogOut[frame * context->analogChannels + channel] = value;
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // analogWriteFrameOnce()
giuliomoro@187: //
giuliomoro@187: // Sets a given channel to a value for only the current frame
giuliomoro@301: static inline void analogWriteFrameOnce(BelaContext *context, int frame, int channel, float value) {
giuliomoro@187: 	context->analogOut[frame * context->analogChannels + channel] = value;
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // digitalReadFrame()
giuliomoro@187: //
giuliomoro@187: // Returns the value of a given digital input at the given frame number
giuliomoro@301: static inline int digitalReadFrame(BelaContext *context, int frame, int channel) {
giuliomoro@187: 	return getBit(context->digital[frame], channel + 16);
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // digitalWriteFrame()
giuliomoro@187: //
giuliomoro@187: // Sets a given digital output channel to a value for the current frame and all subsequent frames
giuliomoro@301: static inline void digitalWriteFrame(BelaContext *context, int frame, int channel, int value) {
giuliomoro@187: 	for(unsigned int f = frame; f < context->digitalFrames; f++) {
giuliomoro@187: 		if(value)
giuliomoro@187: 			context->digital[f] |= 1 << (channel + 16);
giuliomoro@187: 		else
giuliomoro@187: 			context->digital[f] &= ~(1 << (channel + 16));
giuliomoro@187: 	}
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // digitalWriteFrameOnce()
giuliomoro@187: //
giuliomoro@187: // Sets a given digital output channel to a value for the current frame only
giuliomoro@301: static inline void digitalWriteFrameOnce(BelaContext *context, int frame, int channel, int value) {
giuliomoro@187: 	if(value)
giuliomoro@187: 		context->digital[frame] |= 1 << (channel + 16);
giuliomoro@187: 	else
giuliomoro@187: 		context->digital[frame] &= ~(1 << (channel + 16));
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // pinModeFrame()
giuliomoro@187: //
giuliomoro@187: // Sets the direction of a digital pin for the current frame and all subsequent frames
giuliomoro@301: static inline void pinModeFrame(BelaContext *context, int frame, int channel, int mode) {
giuliomoro@187: 	for(unsigned int f = frame; f < context->digitalFrames; f++) {
giuliomoro@187: 		if(mode == INPUT)
giuliomoro@187: 			context->digital[f] |= (1 << channel);
giuliomoro@187: 		else
giuliomoro@187: 			context->digital[f] &= ~(1 << channel);
giuliomoro@187: 	}
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // pinModeFrameOnce()
giuliomoro@187: //
giuliomoro@187: // Sets the direction of a digital pin for the current frame only
giuliomoro@301: static inline void pinModeFrameOnce(BelaContext *context, int frame, int channel, int mode) {
giuliomoro@187: 	if(mode == INPUT)
giuliomoro@187: 		context->digital[frame] |= (1 << channel);
giuliomoro@187: 	else
giuliomoro@187: 		context->digital[frame] &= ~(1 << channel);
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: 
giuliomoro@187: 
giuliomoro@187: // map()
giuliomoro@187: //
giuliomoro@187: // Scale an input value from one range to another. Works like its Wiring language equivalent.
giuliomoro@187: // x is the value to scale; in_min and in_max are the input range; out_min and out_max
giuliomoro@187: // are the output range.
giuliomoro@187: 
giuliomoro@187: static inline float map(float x, float in_min, float in_max, float out_min, float out_max)
giuliomoro@187: {
giuliomoro@187: 	return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
giuliomoro@187: }
giuliomoro@187: 
giuliomoro@187: // constrain()
giuliomoro@187: //
giuliomoro@187: // Clips an input value to be between two end points
giuliomoro@187: // x is the value to constrain; min_val and max_val are the range
giuliomoro@187: 
giuliomoro@187: static inline float constrain(float x, float min_val, float max_val)
giuliomoro@187: {
giuliomoro@187: 	if(x < min_val) return min_val;
giuliomoro@187: 	if(x > max_val) return max_val;
giuliomoro@187: 	return x;
giuliomoro@187: }
andrewm@95: 
andrewm@0: #endif /* UTILITIES_H_ */