Just as an example, below you will find a sample Processing sketch and its openFrameworks equivalent.
Processing
//--------------------------------------------------------------
float bAlpha, cAlpha, radius1, radius2, counter; color cColor = 255;void setup() { size(1024, 768); frameRate(30);}void draw() {// opacity of background reduces as mouse moving down bAlpha = map(mouseY, 0, height, 20, 120); background(bAlpha);// growing center circle, whose color is randomly assigned as key pressed counter = counter + 0.033f; noStroke(); fill(cColor, 80); radius1 = 400*sin(counter); ellipse(width/2, height/2, radius1, radius1);/* surround circles, whose color is consistent with the center one and opacity reduces as mouse moving to the right */ cAlpha = map(mouseX, 0, width, 0, 100); noFill(); stroke(cColor, cAlpha); for(int i = 0; i < 5; i++){ radius2 = random(400, height); ellipse(width/2, height/2, radius2, radius2); } }void keyPressed() { cColor = color(random(255), random(255), random(255));}
openFrameworks
ofApp.cpp
//--------------------------------------------------------------
#include "ofApp.h"//--------------------------------------------------------------void ofApp::setup(){ ofSetCircleResolution(100); ofSetFrameRate(30); counter = 0;}//--------------------------------------------------------------void ofApp::update(){ // counter = counter + 0.033f;}//--------------------------------------------------------------void ofApp::draw(){// opacity of background reduces as mouse moving down float bAlpha = ofMap(mouseY, 0, ofGetHeight(), 20, 120); ofBackground((int) bAlpha); counter = counter + 0.033f;// growing center circle, whose color is randomly assigned as key pressed ofSetColor(cColor, 80); ofFill(); float radius1 = 400 * sin(counter)/2; ofDrawCircle(ofGetWidth()/2, ofGetHeight()/2, radius1); /* surround circles, whose color is consistent with the center one and opacity reduces as mouse moving to the right */ float cAlpha = ofMap(mouseX, 0, ofGetWidth(), 0, 100); ofNoFill(); ofSetColor(cColor, cAlpha); for(int i = 0; i < 5; i++){ float radius2 = (int)ofRandom(400, ofGetHeight())/2; ofDrawCircle(ofGetWidth()/2, ofGetHeight()/2, radius2); } }
//--------------------------------------------------------------void ofApp::keyPressed(int key){ cColor = ofColor((int)ofRandom(0,255),(int)ofRandom(0,255),(int)ofRandom(0,255));}
//--------------------------------------------------------------
ofApp.h
//--------------------------------------------------------------
#pragma once#include "ofMain.h"class ofApp : 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 mouseEntered(int x, int y); void mouseExited(int x, int y); void windowResized(int w, int h); void dragEvent(ofDragInfo dragInfo); void gotMessage(ofMessage msg); float counter; ofColor cColor; };