Pointers

ofApp-arrays.h

#pragma once

#include "ofMain.h"

class ofApp : public ofBaseApp 
{
public:
    void setup();
    void update();
    void draw();

    ofVideoGrabber grabber;
    ofImage resultImg;
};

ofApp-arrays1.cpp

#include "ofApp.h"

void ofApp::setup()
{
    ofSetWindowShape(640 * 2, 480);

    grabber.setup(640, 480);
    resultImg.allocate(640, 480, OF_IMAGE_GRAYSCALE);
}

void ofApp::update()
{
    grabber.update();

    int threshold = 127;

    unsigned char* grabberData = grabber.getPixels().getData();
    unsigned char* resultData = resultImg.getPixels().getData();
    for (int i = 0; i < grabber.getWidth() * grabber.getHeight(); i++)
    {
        int r = grabberData[i * 3 + 0];
        int g = grabberData[i * 3 + 1];
        int b = grabberData[i * 3 + 2];

        if (r > threshold && g > threshold && b > threshold)
        {
            resultData[i] = 255;
        }
        else
        {
            resultData[i] = 0;
        }
    }

    resultImg.update();
}

void ofApp::draw()
{
    grabber.draw(0, 0, 640, 480);
    resultImg.draw(640, 0, 640, 480);
}

ofApp-arrays2.cpp

#include "ofApp.h"

void ofApp::setup()
{
    ofSetWindowShape(640 * 2, 480);

    grabber.setup(640, 480);
    resultImg.allocate(640, 480, OF_IMAGE_GRAYSCALE);
}

void ofApp::update()
{
    grabber.update();

    int threshold = 127;

    unsigned char* grabberPtr = grabber.getPixels().getData();
    unsigned char* resultPtr = resultImg.getPixels().getData();
    for (int i = 0; i < grabber.getWidth() * grabber.getHeight(); i++)
    {
        int r = *(grabberPtr++);
        int g = *(grabberPtr++);
        int b = *(grabberPtr++);

        if (r > threshold && g > threshold && b > threshold)
        {
            *resultPtr = 255;
        }
        else
        {
            *resultPtr = 0;
        }
        resultPtr++;
    }

    resultImg.update();
}

void ofApp::draw()
{
    grabber.draw(0, 0, 640, 480);
    resultImg.draw(640, 0, 640, 480);
}

ofApp-pointers1.cpp

#include "ofApp.h"

void ofApp::setup()
{
    loadImageVal(puppiesImg, "puppies.jpg");
    //loadImageRef(puppiesImg, "puppies.jpg");
    //loadImagePtr(&puppiesImg, "puppies.jpg");
}

void ofApp::update()
{

}

void ofApp::draw()
{
    puppiesImg.draw(0, 0);
}

bool ofApp::loadImageVal(ofImage img, std::string file)
{
    return img.load(file);
}

bool ofApp::loadImageRef(ofImage& img, std::string file)
{
    return img.load(file);
}

bool ofApp::loadImagePtr(ofImage* img, std::string file)
{
    return img->load(file);
}

ofApp-pointers1.h

#pragma once

#include "ofMain.h"

class ofApp : public ofBaseApp 
{
public:
    void setup();
    void update();
    void draw();
    void exit();

    bool loadImageVal(ofImage img, std::string file);
    bool loadImageRef(ofImage& img, std::string file);
    bool loadImagePtr(ofImage* img, std::string file);

    ofImage puppiesImg;
};

ofApp-pointers2.cpp

#include "ofApp.h"

void ofApp::setup()
{
    //puppiesPtr = new ofImage();
    //loadImageVal(*puppiesPtr, "puppies.jpg");
    //loadImageRef(*puppiesPtr, "puppies.jpg");
    loadImagePtr(puppiesPtr, "puppies.jpg");
}

void ofApp::exit()
{
    delete puppiesPtr;
}

void ofApp::update()
{

}

void ofApp::draw()
{
    puppiesPtr->draw(0, 0);
}

bool ofApp::loadImageVal(ofImage img, std::string file)
{
    return img.load(file);
}

bool ofApp::loadImageRef(ofImage& img, std::string file)
{
    return img.load(file);
}

bool ofApp::loadImagePtr(ofImage* img, std::string file)
{
    return img->load(file);
}

ofApp-pointers2.h

#pragma once

#include "ofMain.h"

class ofApp : public ofBaseApp 
{
public:
    void setup();
    void update();
    void draw();
    void exit();

    bool loadImageVal(ofImage img, std::string file);
    bool loadImageRef(ofImage& img, std::string file);
    bool loadImagePtr(ofImage* img, std::string file);

    ofImage* puppiesPtr;
};

ofApp-pointers3.cpp

#include "ofApp.h"

void ofApp::setup()
{
    puppiesPtrToLoad = new ofImage();
    loadImagePtr(puppiesPtrToLoad, "puppies.jpg");

    puppiesPtrToDraw = puppiesPtrToLoad;
}

void ofApp::exit()
{
    delete puppiesPtrToLoad;
    puppiesPtrToLoad = nullptr;
}

void ofApp::update()
{

}

void ofApp::draw()
{
    if (puppiesPtrToDraw != nullptr)
    {
        puppiesPtrToDraw->draw(0, 0);
    }
}

void ofApp::mousePressed(int x, int y, int button)
{
    delete puppiesPtrToLoad;
    puppiesPtrToLoad = nullptr;
}

bool ofApp::loadImagePtr(ofImage* img, std::string file)
{
    return img->load(file);
}

ofApp-pointers3.h

#pragma once

#include "ofMain.h"

class ofApp : public ofBaseApp 
{
public:
    void setup();
    void update();
    void draw();
    void exit();

    void mousePressed(int x, int y, int button);

    bool loadImagePtr(ofImage* img, std::string file);

    ofImage* puppiesPtrToLoad;
    ofImage* puppiesPtrToDraw;
};

ofApp-sharedPtr.cpp

#include "ofApp.h"

void ofApp::setup()
{
    puppiesPtrToLoad = std::make_shared<ofImage>();
    loadImagePtr(puppiesPtrToLoad, "puppies.jpg");

    puppiesPtrToDraw = puppiesPtrToLoad;
}

void ofApp::update()
{

}

void ofApp::draw()
{
    if (puppiesPtrToDraw)
    {
        puppiesPtrToDraw->draw(0, 0);
    }
}

void ofApp::mousePressed(int x, int y, int button)
{
    if (button == 0)
    {
        puppiesPtrToLoad.reset();
    }
    else
    {
        puppiesPtrToDraw.reset();
    }
}

bool ofApp::loadImagePtr(std::shared_ptr<ofImage> img, std::string file)
{
    return img->load(file);
}

ofApp-sharedPtr.h

#pragma once

#include "ofMain.h"

class ofApp : public ofBaseApp 
{
public:
    void setup();
    void update();
    void draw();

    void mousePressed(int x, int y, int button);

    bool loadImagePtr(std::shared_ptr<ofImage> img, std::string file);

    std::shared_ptr<ofImage> puppiesPtrToLoad;
    std::shared_ptr<ofImage> puppiesPtrToDraw;
};