comparison examples/11-Extras/stepper/render.cpp @ 464:8fcfbfb32aa0 prerelease

Examples reorder with subdirectories. Added header to each project. Moved Doxygen to bottom of render.cpp.

+/*
+ ____  _____ _        _    
+| __ )| ____| |      / \   
+|  _ \|  _| | |     / _ \  
+| |_) | |___| |___ / ___ \ 
+|____/|_____|_____/_/   \_\
+
+The platform for ultra-low latency audio and sensor processing
+
+http://bela.io
+
+A project of the Augmented Instruments Laboratory within the
+Centre for Digital Music at Queen Mary University of London.
+http://www.eecs.qmul.ac.uk/~andrewm
+
+(c) 2016 Augmented Instruments Laboratory: Andrew McPherson,
+  Astrid Bin, Liam Donovan, Christian Heinrichs, Robert Jack,
+  Giulio Moro, Laurel Pardue, Victor Zappi. All rights reserved.
+
+The Bela software is distributed under the GNU Lesser General Public License
+(LGPL 3.0), available here: https://www.gnu.org/licenses/lgpl-3.0.txt
+*/
+
+
+#include <Bela.h>
+
+const int kStepLengthSlow = 1000;
+const int kStepLengthFast = 500;
+
+int gStepLengthSamples = kStepLengthSlow;
+
+const int gPinA1 = P8_27;
+const int gPinA2 = P8_28;
+const int gPinB1 = P8_29;
+const int gPinB2 = P8_30;
+const int gPinServo = P9_16;
+
+int gStepCounter = 0;
+int gPhase = 0;
+
+int gServoCounter = 0;
+
+
+enum {
+	kStateMoveRight1 = 0,
+	kStateMoveLeft1,
+	kStateMoveRight2,
+	kStateMoveLeft2,
+	kStateMoveRight3,
+	kStateMoveLeft3,
+	kStateSpin,
+	kStateMax
+};
+
+int gState = 0;
+int gStateCounter = 0;
+
+// setup() is called once before the audio rendering starts.
+// Use it to perform any initialisation and allocation which is dependent
+// on the period size or sample rate.
+//
+// userData holds an opaque pointer to a data structure that was passed
+// in from the call to initAudio().
+//
+// Return true on success; returning false halts the program.
+
+bool setup(BelaContext *context, void *userData)
+{	
+	// This project makes the assumption that the audio and digital
+	// sample rates are the same. But check it to be sure!
+	if(context->audioFrames != context->digitalFrames) {
+		rt_printf("Error: this project needs the audio and digital sample rates to be the same.\n");
+		return false;
+	}
+	
+	pinMode(context, 0, gPinA1, OUTPUT);
+	pinMode(context, 0, gPinA2, OUTPUT);
+	pinMode(context, 0, gPinB1, OUTPUT);
+	pinMode(context, 0, gPinB2, OUTPUT);
+	pinMode(context, 0, gPinServo, OUTPUT);
+		
+	return true;
+}
+
+// render() is called regularly at the highest priority by the audio engine.
+// Input and output are given from the audio hardware and the other
+// ADCs and DACs (if available). If only audio is available, numMatrixFrames
+// will be 0.
+
+void render(BelaContext *context, void *userData)
+{
+	for(unsigned int n = 0; n < context->audioFrames; n++) {
+		if(gPhase == 0 || gPhase == 1) {
+			digitalWriteOnce(context, n, gPinB1, HIGH);
+			digitalWriteOnce(context, n, gPinB2, LOW);
+		}
+		else {
+			digitalWriteOnce(context, n, gPinB1, LOW);
+			digitalWriteOnce(context, n, gPinB2, HIGH);			
+		}
+		
+		if(gPhase == 1 || gPhase == 2) {
+			digitalWriteOnce(context, n, gPinA1, HIGH);
+			digitalWriteOnce(context, n, gPinA2, LOW);
+		}
+		else {
+			digitalWriteOnce(context, n, gPinA1, LOW);
+			digitalWriteOnce(context, n, gPinA2, HIGH);			
+		}
+		
+		if(--gServoCounter > 0) 
+			digitalWriteOnce(context, n, gPinServo, HIGH);
+		else
+			digitalWriteOnce(context, n, gPinServo, LOW);
+		
+		if(++gStepCounter >= gStepLengthSamples) {
+			gStateCounter++;
+			
+			switch(gState) {
+				case kStateMoveRight1:
+				case kStateMoveRight2:
+				case kStateMoveRight3:
+					gPhase = (gPhase + 1) & 3;
+					break;
+				case kStateMoveLeft1:
+				case kStateMoveLeft2:
+				case kStateMoveLeft3:				
+					gPhase = (gPhase + 3) & 3;	
+					break;
+				case kStateSpin:
+					gPhase = (gPhase + 1) & 3;
+					break;		
+			}
+			
+			if(gState == kStateSpin) {
+				if(gStateCounter >= 48) {
+					gStateCounter = 0;
+					gState = 0;
+					gStepLengthSamples = kStepLengthSlow;
+				}				
+			}
+			else {
+				if(gStateCounter >= 16) {
+					gStateCounter = 0;
+					gState++;
+					if(gState & 1)
+						gServoCounter = 120;
+					else
+						gServoCounter = 80;
+					if(gState == kStateSpin)
+						gStepLengthSamples = kStepLengthFast;
+				}
+			}
+			
+			gStepCounter = 0;
+		}
+	}
+}
+
+// cleanup() is called once at the end, after the audio has stopped.
+// Release any resources that were allocated in setup().
+
+void cleanup(BelaContext *context, void *userData)
+{
+	
+}