Alvaro Cassinelli / Mbed 2 deprecated laserUI

Laser Sensing Display for UI interfaces in the real world

Dependencies:   mbed

Fork of skinGames_forktest by Alvaro Cassinelli

classLaserSensingTrajectory.cpp@47:199042980678, 2014-04-17 (annotated)

Committer:
mbedalvaro
Date:
Thu Apr 17 08:04:14 2014 +0000
Revision:
47:199042980678
Parent:
40:3ba2b0ea9f33 
publishing for sharing with Ken Iwasaki

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbedalvaro 32:52273c3291fe 1 #include "classLaserSensingTrajectory.h"
mbedalvaro 36:233b12d0b1f0 2 using namespace std;
mbedalvaro 32:52273c3291fe 3
mbedalvaro 32:52273c3291fe 4 LaserSensingTrajectory::LaserSensingTrajectory():lightTouched(false),
mbedalvaro 36:233b12d0b1f0 5 min_contrast_ratio(MIN_CONTRAST_RATIO), threshold_factor(THRESHOLD_FACTOR),
mbedalvaro 36:233b12d0b1f0 6 min_acceptable_intensity(MIN_ACCEPTABLE_INTENSITY), fixedThreshold(FIXED_THRESHOLD)
mbedalvaro 36:233b12d0b1f0 7 {
mbedalvaro 36:233b12d0b1f0 8 lsdTrajectory.clear(); // no need in principle! the constructor of the vector will give an empty vector!
mbedalvaro 36:233b12d0b1f0 9 // attention: properly set the state of the threshold switch in the IO.init (which by the way, in THIS hardware
mbedalvaro 36:233b12d0b1f0 10 // implementation indicates the state for ALL the objects..)
mbedalvaro 36:233b12d0b1f0 11 modeThreshold=AUTO;
mbedalvaro 36:233b12d0b1f0 12 // IO.setSwitchOneState(true);
mbedalvaro 32:52273c3291fe 13 }
mbedalvaro 32:52273c3291fe 14
mbedalvaro 32:52273c3291fe 15 LaserSensingTrajectory::~LaserSensingTrajectory() {
mbedalvaro 32:52273c3291fe 16 // lsdTrajectory.clear(); // there is no need to clear the vector, the destructor of this vector is called by default (and it's NOT a vector of pointers)
mbedalvaro 32:52273c3291fe 17 }
mbedalvaro 32:52273c3291fe 18
mbedalvaro 32:52273c3291fe 19
mbedalvaro 32:52273c3291fe 20 void LaserSensingTrajectory::setDelayMirrors(int delay) {
mbedalvaro 32:52273c3291fe 21 delayMirrorSamples=delay;
mbedalvaro 32:52273c3291fe 22 }
mbedalvaro 32:52273c3291fe 23
mbedalvaro 32:52273c3291fe 24 void LaserSensingTrajectory::addDelayMirrors(int add_delay) {
mbedalvaro 32:52273c3291fe 25 delayMirrorSamples+=add_delay;
mbedalvaro 32:52273c3291fe 26 }
mbedalvaro 32:52273c3291fe 27
mbedalvaro 36:233b12d0b1f0 28 bool LaserSensingTrajectory::processSensedData() {
mbedalvaro 32:52273c3291fe 29 // Compute max and min intensity on the loop
mbedalvaro 32:52273c3291fe 30 maxI=0;
mbedalvaro 32:52273c3291fe 31 minI=255; // ratio has been normalized between 0 and 255
mbedalvaro 36:233b12d0b1f0 32 unsigned short auxSize=lsdTrajectory.size(); // could be an unsigned char in principle... no more than 255 points per object, but well, memory in future versions
mbedalvaro 36:233b12d0b1f0 33 // of the microprocessor can be larger.
mbedalvaro 32:52273c3291fe 34
mbedalvaro 32:52273c3291fe 35 // Compute minimum and maximum intensities:
mbedalvaro 36:233b12d0b1f0 36 for (unsigned short i = 0; i < auxSize; i++) {
mbedalvaro 32:52273c3291fe 37 unsigned char mesI=lsdTrajectory[i].intensity;
mbedalvaro 32:52273c3291fe 38 if (maxI<mesI) maxI=mesI;
mbedalvaro 32:52273c3291fe 39 if (minI>mesI) minI=mesI;
mbedalvaro 32:52273c3291fe 40 }
mbedalvaro 32:52273c3291fe 41
mbedalvaro 32:52273c3291fe 42 // Compute autoThreshold:
mbedalvaro 33:43e8bc451ef0 43 switch(modeThreshold) {
mbedalvaro 33:43e8bc451ef0 44 case AUTO:
mbedalvaro 33:43e8bc451ef0 45 if (minI==0) minI=1;
mbedalvaro 34:1244fa3f2559 46 if (maxI<min_acceptable_intensity) autoThreshold=255;// (we consider that the saccade is FULL on something black - this is noise)
mbedalvaro 33:43e8bc451ef0 47 else if (1.0*maxI/minI > min_contrast_ratio ) {
mbedalvaro 33:43e8bc451ef0 48 autoThreshold = (unsigned char) (1.0 * (maxI-minI) * threshold_factor + minI); // threshold_factor = 2/3 or 1/2 is a good value.
mbedalvaro 33:43e8bc451ef0 49 } else {// ... otherwise, we consider that the saccade is FULL on something white
mbedalvaro 33:43e8bc451ef0 50 autoThreshold=0;
mbedalvaro 33:43e8bc451ef0 51 }
mbedalvaro 34:1244fa3f2559 52 break;
mbedalvaro 33:43e8bc451ef0 53 case FIXED:
mbedalvaro 33:43e8bc451ef0 54 autoThreshold=fixedThreshold;
mbedalvaro 34:1244fa3f2559 55 break;
mbedalvaro 32:52273c3291fe 56 }
mbedalvaro 34:1244fa3f2559 57
mbedalvaro 32:52273c3291fe 58
mbedalvaro 32:52273c3291fe 59 // Segment the trajectory (only two levels for the time being, but we can have more - meaning different forces, real or even complex values to have different angle forces...):
mbedalvaro 32:52273c3291fe 60 // NOTE: if using 1 and -1 instead of 1 and 0, we can avoid having to add a "blob internal pressure"! -1 means a force towards the interior, and +1 outwards...
mbedalvaro 32:52273c3291fe 61 // This means that the loop will naturally become inside-out depending on the color of the main surface! (but will mantain its normal size). Much better and elegant solution than the
mbedalvaro 32:52273c3291fe 62 // idea of the blob "constant" internal pressure...
mbedalvaro 36:233b12d0b1f0 63 bool isLightZone=false, isDarkZone=false;
mbedalvaro 36:233b12d0b1f0 64 for (unsigned short i = 0; i < auxSize; i++) {
mbedalvaro 36:233b12d0b1f0 65 unsigned short delayedpoint=(i+auxSize+delayMirrorSamples)%auxSize; // this way we can have negative delayMirrorSamples if required (would be absurd though)
mbedalvaro 32:52273c3291fe 66 if (lsdTrajectory[delayedpoint].intensity>=autoThreshold) { // this means a WHITE zone:
mbedalvaro 40:3ba2b0ea9f33 67 lsdTrajectory[i].lightZone= 1;
mbedalvaro 36:233b12d0b1f0 68 isLightZone=true;
mbedalvaro 36:233b12d0b1f0 69 } else { // this means DARK ZONE
mbedalvaro 40:3ba2b0ea9f33 70 lsdTrajectory[i].lightZone= 0;
mbedalvaro 36:233b12d0b1f0 71 isDarkZone=true;
mbedalvaro 32:52273c3291fe 72 }
mbedalvaro 32:52273c3291fe 73 }
mbedalvaro 36:233b12d0b1f0 74
mbedalvaro 36:233b12d0b1f0 75 // In the case of AUTO mode, we assume that something is touching the object when the trajectory has at least one light zone and one dark zone;
mbedalvaro 36:233b12d0b1f0 76 // in the case of FIXED mode, we assume something is touching the object when there is at least one light zone (this is a convention, because it depends
mbedalvaro 36:233b12d0b1f0 77 // on the background - but we can argue that "no background" corresponds to no reflection (then dark), and, say, a ping pong ball or finger is front
mbedalvaro 36:233b12d0b1f0 78 // will be "light":
mbedalvaro 36:233b12d0b1f0 79 if (modeThreshold==FIXED)
mbedalvaro 36:233b12d0b1f0 80 lightTouched=isLightZone;
mbedalvaro 36:233b12d0b1f0 81 else
mbedalvaro 36:233b12d0b1f0 82 lightTouched=isLightZone&&isDarkZone; // assuming only two modes for modeThreshold
mbedalvaro 36:233b12d0b1f0 83
mbedalvaro 36:233b12d0b1f0 84 // Return lightTouched for commodity:
mbedalvaro 36:233b12d0b1f0 85 return(lightTouched);
mbedalvaro 32:52273c3291fe 86 }
mbedalvaro 40:3ba2b0ea9f33 87