The document defines a class called ofBlob that represents a circle object that can be drawn and manipulated. It includes private variables to store the blob's position, dimension, speed, and phase. Methods are defined to initialize the blob, set/get its properties, update its position, and draw it. A testApp class is also defined that initializes a vector of ofBlob objects and calls their update and draw methods in a loop.

13. #include <iostream>
using namespace std;
class Dog { // Dog
public:
string name; // ( )
void bark(); // ( )
}; //Dog ( ";" )
int main (int argc, char * const argv[]) { //
}

14. software systems.
Interface and Implementation
To invent programs, you need to be able to capture abstractions and express them in t
design. It’s the job of a programming language to help you do this. The language shoul
process of invention and design by letting you encode abstractions that reveal the way
It should let you make your ideas concrete in the code you write. Surface details shou
the architecture of your program.
All programming languages provide devices that help express abstractions. In essence
are ways of grouping implementation details, hiding them, and giving them, at least t
a common interface—much as a mechanical object separates its interface from its impl
illustrated in “Interface and Implementation” .
Figure 2-1 Inte rfa ce a nd Im ple m e nta tion
interface implementation
11
10
9
8
7
6
Looking at such a unit from the inside, as the implementor, you’d be concerned with w
composed of and how it works. Looking at it from the outside, as the user, you’re conc
with what it is and what it does. You can look past the details and think solely in term

15. :: ( ){
//
}

16. #include <iostream>
using namespace std;
class Dog { // Dog
public:
string name; // ( )
void bark(); // ( )
}; //Dog ( ";" )
void Dog::bark() { //Dog bark()
//
cout << name << " ! " << endl;
}
int main (int argc, char * const argv[]) { //
}

17. #include <iostream>
using namespace std;
class Dog { // Dog
public:
string name; // ( )
void bark(); // ( )
}; //Dog ( ";" )
void Dog::bark() { //Dog bark()
//
cout << name << " ! " << endl;
}
int main (int argc, char * const argv[]) { //
Dog hachi; //Dog hachi
}

18. #include <iostream>
using namespace std;
class Dog { // Dog
public:
string name; // ( )
void bark(); // ( )
}; //Dog ( ";" )
void Dog::bark() { //Dog bark()
//
cout << name << " ! " << endl;
}
int main (int argc, char * const argv[]) { //
Dog hachi; //Dog hachi
hachi.name = " "; //hachi name " "
}

19. #include <iostream>
using namespace std;
class Dog { // Dog
public:
string name; // ( )
void bark(); // ( )
}; //Dog ( ";" )
void Dog::bark() { //Dog bark()
//
cout << name << " ! " << endl;
}
int main (int argc, char * const argv[]) { //
Dog hachi; //Dog hachi
hachi.name = " "; //hachi name " "
hachi.bark(); //hachi bark()
}

20. run
[Switching to process xxxx]
!
...
Debugger stopped.
Program exited with status value:0.

22. #include "Dog.h"
int main (int argc, char * const argv[]) { //
Dog hachi; //Dog hachi
hachi.name = " "; //hachi name " "
hachi.bark(); //hachi bark()
}

23. #include <iostream>
using namespace std;
class Dog { // Dog
public:
string name; // ( )
void bark(); // ( )
}; //Dog ( ";" )

24. #include "Dog.h"
void Dog::bark() { //Dog bark()
//
cout << name << " ! " << endl;
}

26. #ifndef _TEST_APP
#define _TEST_APP
#include "ofMain.h"
class testApp : public ofBaseApp {
public:
void setup();
void update();
void draw();
void keyPressed (int key);
void keyReleased(int key);
void mouseMoved(int x, int y );
void mouseDragged(int x, int y, int button);
void mousePressed(int x, int y, int button);
void mouseReleased(int x, int y, int button);
void windowResized(int w, int h);
};
#endif

27. #include "testApp.h"
void testApp::setup(){
}
void testApp::update(){
}
void testApp::draw(){
}
void testApp::keyPressed(int key){
}
void testApp::keyReleased(int key){
}
void testApp::mouseMoved(int x, int y){
}
void testApp::mouseDragged(int x, int y, int button){
}
void testApp::mousePressed(int x, int y, int button){
}
void testApp::mouseReleased(int x, int y, int button){
}
void testApp::windowResized(int w, int h){
}

36. #ifndef _TEST_APP
#define _TEST_APP
#include "ofMain.h"
#include "ofBlob.h"
class testApp : public ofBaseApp {
public:
void setup();
void update();
void draw();
void keyPressed (int key);
void keyReleased(int key);
void mouseMoved(int x, int y );
void mouseDragged(int x, int y, int button);
void mousePressed(int x, int y, int button);
void mouseReleased(int x, int y, int button);
void windowResized(int w, int h);
ofBlob blob; //ofBlob
};
#endif

37. #include "testApp.h"
void testApp::setup(){
//
ofBackground(0, 0, 0);
ofSetCircleResolution(64);
ofEnableAlphaBlending();
ofSetFrameRate(30);
}
void testApp::update(){
}
void testApp::draw(){
blob.draw(); //blob draw()
}
...( )

38. #ifndef _OF_BLOB
#define _OF_BLOB
#include "ofMain.h"
class ofBlob {
public:
// method
void draw();
};
#endif

39. #include "ofBlob.h"
void ofBlob::draw()
{
ofSetColor(31, 63, 255);
ofCircle(ofGetWidth()/2, ofGetHeight()/2, 100);
}

43. #ifndef _TEST_APP
#define _TEST_APP
#include "ofMain.h"
#include "ofBlob.h"
class testApp : public ofBaseApp {
public:
void setup();
void update();
void draw();
void keyPressed (int key);
void keyReleased(int key);
void mouseMoved(int x, int y );
void mouseDragged(int x, int y, int button);
void mousePressed(int x, int y, int button);
void mouseReleased(int x, int y, int button);
void windowResized(int w, int h);
ofBlob blob; //ofBlob
};
#endif

44. #include "testApp.h"
void testApp::setup(){
//
ofBackground(0, 0, 0);
ofSetCircleResolution(32);
ofEnableAlphaBlending();
ofSetFrameRate(30);
blob.setPos(ofPoint(300, 400)); //blob
blob.setDim(80); //blob
}
void testApp::update(){
}
void testApp::draw(){
blob.draw(); //blob draw()
}
...( )

45. #ifndef _OF_BLOB
#define _OF_BLOB
#include "ofMain.h"
class ofBlob {
private:
float dim; //
ofPoint pos; //
public:
void setDim(float dim); //dim
float getDim(); //dim
void setPos(ofPoint pos); //pos
ofPoint getPos(); //pos
void draw(); //
};
#endif

46. #include "ofBlob.h"
void ofBlob::setDim(float _dim)
{
dim = _dim;
}
float ofBlob::getDim()
{
return dim;
}
void ofBlob::setPos(ofPoint _pos)
{
pos = _pos;
}
ofPoint ofBlob::getPos()
{
return pos;
}
void ofBlob::draw()
{
ofSetColor(31, 63, 255);
ofCircle(pos.x, pos.y, dim);

50. #ifndef _TEST_APP
#define _TEST_APP
#include "ofMain.h"
#include "ofBlob.h"
class testApp : public ofBaseApp {
public:
void setup();
void update();
void draw();
void keyPressed (int key);
void keyReleased(int key);
void mouseMoved(int x, int y );
void mouseDragged(int x, int y, int button);
void mousePressed(int x, int y, int button);
void mouseReleased(int x, int y, int button);
void windowResized(int w, int h);
ofBlob blob; //ofBlob
};

51. #include "testApp.h"
void testApp::setup(){
//
ofBackground(0, 0, 0);
ofSetCircleResolution(32);
ofEnableAlphaBlending();
ofSetFrameRate(30);
blob.setPos(ofPoint(300, 400)); //blob
blob.setDim(80); //blob
blob.setSpeed(ofPoint(8,5)); //
}
void testApp::update(){
blob.update();
}
void testApp::draw(){
blob.draw(); //blob draw()
}
...( )

52. #ifndef _OF_BLOB
#define _OF_BLOB
#include "ofMain.h"
class ofBlob {
private:
float dim; //
ofPoint pos; //
ofPoint speed; //
public:
void setDim(float dim); //dim
float getDim(); //dim
void setPos(ofPoint pos); //pos
ofPoint getPos(); //pos
void setSpeed(ofPoint speed); //speed
ofPoint getSpeed(); //speed
void update(); //
void draw(); //
};

53. #include "ofBlob.h"
void ofBlob::setDim(float _dim)
{
dim = _dim;
}
float ofBlob::getDim()
{
return dim;
}
void ofBlob::setPos(ofPoint _pos)
{
pos = _pos;
}
ofPoint ofBlob::getPos()
{
return pos;
}
void ofBlob::setSpeed(ofPoint _speed)
{

54. ofPoint ofBlob::getSpeed()
{
return speed;
}
void ofBlob::update()
{
pos.x += speed.x;
pos.y += speed.y;
if(pos.x < dim || pos.x > ofGetWidth()-dim){
speed.x *= -1;
}
if(pos.y < dim || pos.y > ofGetHeight()-dim){
speed.y *= -1;
}
}
void ofBlob::draw()
{
ofSetColor(31, 63, 255);
ofCircle(pos.x, pos.y, dim);
}

58. #ifndef _OF_BLOB
#define _OF_BLOB
#include "ofMain.h"
class ofBlob {
private:
float dim; //
ofPoint pos; //
ofPoint speed; //
float moveDim; //
float phase; //
float phaseSpeed; //
public:
ofBlob(); //
void setDim(float dim); //dim
float getDim(); //dim
void setPos(ofPoint pos); //pos
ofPoint getPos(); //pos

59. ofPoint getSpeed(); //speed
void update(); //
void draw(); //
};
#endif

60. #include "ofBlob.h"
ofBlob::ofBlob()
{
phaseSpeed = ofRandom(0.1, 0.2);
phase = 0;
}
void ofBlob::setDim(float _dim)
{
dim = _dim;
}
float ofBlob::getDim()
{
return dim;
}
void ofBlob::setPos(ofPoint _pos)
{
pos = _pos;
}

61. ofPoint ofBlob::getPos()
{
return pos;
}
void ofBlob::setSpeed(ofPoint _speed)
{
speed = _speed;
}
ofPoint ofBlob::getSpeed()
{
return speed;
}
void ofBlob::update()
{
moveDim = dim + sin(phase)*dim/4;
phase += phaseSpeed;
if(phase > TWO_PI){
phase -= TWO_PI;
}
pos.x += speed.x;
pos.y += speed.y;

62. if(pos.x < dim || pos.x > ofGetWidth()-dim){
speed.x *= -1;
}
if(pos.y < dim || pos.y > ofGetHeight()-dim){
speed.y *= -1;
}
}
void ofBlob::draw()
{
ofSetColor(31, 63, 255, 200);
ofCircle(pos.x, pos.y, moveDim);
}

65. #ifndef _TEST_APP
#define _TEST_APP
#include "ofMain.h"
#include "ofBlob.h"
class testApp : public ofBaseApp {
public:
void setup();
void update();
void draw();
void keyPressed (int key);
void keyReleased(int key);
void mouseMoved(int x, int y );
void mouseDragged(int x, int y, int button);
void mousePressed(int x, int y, int button);
void mouseReleased(int x, int y, int button);
void windowResized(int w, int h);
vector <ofBlob> blobs; //ofBlob Vector
};

66. #include "testApp.h"
void testApp::setup(){
ofBackground(0, 0, 0);
ofSetCircleResolution(64);
ofEnableAlphaBlending();
ofSetFrameRate(30);
}
void testApp::update(){
for (int i = 0; i < blobs.size(); i++) {
blobs[i].update();
}
}
void testApp::draw(){
for (int i = 0; i < blobs.size(); i++) {
blobs[i].draw();
}
}
...( )...

67. void testApp::mouseReleased(int x, int y, int button){
ofBlob b = ofBlob(); // ofBlob
b.setPos(ofPoint(mouseX, mouseY)); //
b.setDim(ofRandom(10,40)); //
b.setSpeed(ofPoint(ofRandom(-5, 5), ofRandom(-5, 5))); //
blobs.push_back(b);
}
...( )

68. #ifndef _OF_BLOB
#define _OF_BLOB
#include "ofMain.h"
class ofBlob {
private:
float dim; //
ofPoint pos; //
ofPoint speed; //
float moveDim; //
float phase; //
float phaseSpeed; //
public:
ofBlob(); //
void setDim(float dim); //dim
float getDim(); //dim
void setPos(ofPoint pos); //pos
ofPoint getPos(); //pos

69. ofPoint getSpeed(); //speed
void update(); //
void draw(); //
};
#endif

70. #include "ofBlob.h"
ofBlob::ofBlob()
{
phaseSpeed = ofRandom(0.1, 0.2);
phase = 0;
}
void ofBlob::setDim(float _dim)
{
dim = _dim;
}
float ofBlob::getDim()
{
return dim;
}
void ofBlob::setPos(ofPoint _pos)
{
pos = _pos;
}
ofPoint ofBlob::getPos()
{
return pos;

71. void ofBlob::setSpeed(ofPoint _speed)
{
speed = _speed;
}
ofPoint ofBlob::getSpeed()
{
return speed;
}
void ofBlob::update()
{
moveDim = dim + sin(phase)*dim/4;
phase += phaseSpeed;
if(phase > TWO_PI){
phase -= TWO_PI;
}
pos.x += speed.x;
pos.y += speed.y;
if(pos.x < dim || pos.x > ofGetWidth()-dim){
speed.x *= -1;
}
if(pos.y < dim || pos.y > ofGetHeight()-dim){
speed.y *= -1;
}
}

72. void ofBlob::draw()
{
ofSetColor(31, 63, 255, 80);
ofCircle(pos.x, pos.y, moveDim);
ofSetColor(255, 63, 31);
ofCircle(pos.x, pos.y, dim/10);
}

75. #ifndef _TEST_APP
#define _TEST_APP
#include "ofMain.h"
#include "ofBlob.h"
class testApp : public ofBaseApp {
public:
void setup();
void update();
void draw();
void keyPressed (int key);
void keyReleased(int key);
void mouseMoved(int x, int y );
void mouseDragged(int x, int y, int button);
void mousePressed(int x, int y, int button);
void mouseReleased(int x, int y, int button);
void windowResized(int w, int h);
vector <ofBlob> blobs; //ofBlob Vector
};

76. #include "testApp.h"
void testApp::setup(){
ofBackground(0, 0, 0);
ofSetCircleResolution(64);
ofEnableAlphaBlending();
ofSetFrameRate(30);
ofBlob b = ofBlob();
b.setPos(ofPoint(ofGetWidth()/2, ofGetHeight()/2));
b.setDim(ofGetHeight()/3);
blobs.push_back(b);
}
void testApp::update(){
for (int i = 0; i < blobs.size(); i++) {
blobs[i].update();
}
}
void testApp::draw(){
for (int i = 0; i < blobs.size(); i++) {
blobs[i].draw();
}

77. void testApp::keyPressed(int key){
switch (key) {
case 'f':
ofSetFullscreen(true);
break;
}
}
void testApp::keyReleased(int key){
}
void testApp::mouseMoved(int x, int y){
}
void testApp::mouseDragged(int x, int y, int button){
}
void testApp::mousePressed(int x, int y, int button){
int bSize = blobs.size();
for (int i = 0; i < bSize; i++) {
ofPoint p = blobs[i].getPos();
float dist = ofDist(p.x, p.y, mouseX, mouseY);
float dim = blobs[i].getDim();
ofPoint pos = blobs[i].getPos();

78. if(dist < dim){
//
blobs[i].setDim(dim*0.6);
blobs[i].setPos(ofPoint(pos.x-dim/2,pos.y-dim/2));
blobs[i].setSpeed(ofPoint(ofRandom(-dim/150,dim/150),ofRandom(-dim/150,dim/
150)));
// 1
ofBlob b1 = ofBlob();
b1.setDim(dim*0.6);
b1.setPos(ofPoint(pos.x+dim/2,pos.y+dim/2));
b1.setSpeed(ofPoint(ofRandom(-dim/150,dim/150),ofRandom(-dim/150,dim/
150)));
blobs.push_back(b1);
// 2
ofBlob b2 = ofBlob();
b2.setDim(dim*0.6);
b2.setPos(ofPoint(pos.x-dim/2,pos.y+dim/2));
b2.setSpeed(ofPoint(ofRandom(-dim/150,dim/150),ofRandom(-dim/150,dim/
150)));
blobs.push_back(b2);

79. // 3
ofBlob b3 = ofBlob();
b3.setDim(dim*0.6);
b3.setPos(ofPoint(pos.x+dim/2,pos.y-dim/2));
b3.setSpeed(ofPoint(ofRandom(-dim/150,dim/150),ofRandom(-dim/150,dim/
150)));
blobs.push_back(b3);
}
}
}
void testApp::mouseReleased(int x, int y, int button){
//ofBlob b = ofBlob(ofPoint(mouseX, mouseY));
//blobs.push_back(b);
}
void testApp::windowResized(int w, int h){
}

80. #ifndef _OF_BLOB
#define _OF_BLOB
#include "ofMain.h"
class ofBlob {
private:
float dim; //
ofPoint pos; //
ofPoint speed; //
float moveDim; //
float phase; //
float phaseSpeed; //
public:
ofBlob(); //
void setDim(float dim); //dim
float getDim(); //dim
void setPos(ofPoint pos); //pos
ofPoint getPos(); //pos

81. ofPoint getSpeed(); //speed
void update(); //
void draw(); //
};
#endif

82. #include "ofBlob.h"
ofBlob::ofBlob()
{
phaseSpeed = ofRandom(0.1, 0.2);
phase = 0;
}
void ofBlob::setDim(float _dim)
{
dim = _dim;
}
float ofBlob::getDim()
{
return dim;
}
void ofBlob::setPos(ofPoint _pos)
{
pos = _pos;
}
ofPoint ofBlob::getPos()
{
return pos;

83. void ofBlob::setSpeed(ofPoint _speed)
{
speed = _speed;
}
ofPoint ofBlob::getSpeed()
{
return speed;
}
void ofBlob::update()
{
moveDim = dim + sin(phase)*dim/4;
phase += phaseSpeed;
if(phase > TWO_PI){
phase -= TWO_PI;
}
pos.x += speed.x;
pos.y += speed.y;
if(pos.x < dim || pos.x > ofGetWidth()-dim){
speed.x *= -1;
}
if(pos.y < dim || pos.y > ofGetHeight()-dim){
speed.y *= -1;
}
}

84. void ofBlob::draw()
{
ofSetColor(31, 63, 255, 80);
ofCircle(pos.x, pos.y, moveDim);
ofSetColor(255, 63, 31);
ofCircle(pos.x, pos.y, dim/10);
}