I want to only use the wheel to zoom in and out and the center of our view is where the new dot is draw, but I fail to do so, anybody an idea how to solve that?
float sFactor = 1.0;
float transX = 0.0;
float transY = 0.0;//variable for zoom in and out.
float datas[][] = null;//vertor space for the offsets
float rp[][] = null;//distance and angle from 0,0
float Rspeed = 0.011;//rotation speed
PGraphics posi = null;
PGraphics cord = null;//rendering API
PVector size = new PVector(1, 1); // pixel/unit
PVector lastPos = new PVector();
float t = -0f;//init t.If you want program to start drawing at beginning,set this to 0.
float at = 0f;
float atv = 0.1f;
float atf = 100f;
float atT = 0.5f;
int reversey = 1;
void setup() {
size(980, 980);
String[] lines = loadStrings("datas.txt");
datas = new float[lines.length][2];
rp = new float[lines.length][2];//load math datas into vectors
for (int i = 0; i < lines.length; i++) {
String cache[] = split(lines[i], ",");
if (cache.length<2) {break;}//convert vector into two part by ",",when no more datas stop loop.
datas[i][0] = Float.parseFloat(cache[0].replace("[",""));
datas[i][1] = Float.parseFloat(cache[1].replace("]",""));//delect [&] in data to get pure numbers.
rp[i][0] = sqrt(datas[i][0]*datas[i][0]+datas[i][1]*datas[i][1]);//pythagorean theorem get distance
rp[i][1] = atan2(datas[i][1],datas[i][0]);//tan to get angle
}
posi = createGraphics(width, height);
cord = createGraphics(width, height);
cord.beginDraw();
cord.stroke(0,15,25,100);
cord.line(0, cord.height/2f, cord.width, cord.height/2f);
cord.line(cord.width/2f, 0, cord.width/2f, cord.height);
cord.endDraw();
}
void draw() {
background(255);
pushMatrix();
if(sFactor !=1){translate(transX,transY);}
scale(sFactor);
t+=Rspeed;
at+=atv;
image(cord, 0, 0);
PVector center = new PVector();
PVector pointer = new PVector();
noFill();
stroke(255);
for (int i = 0; i<datas.length; i++) {
int m = 0;
float aph = map(sin(((1-(float)i/datas.length)*atf+at)/atT),-1,1,50,255);
if (i>0) m = ((i+1)/2)*((i%2 == 0)?-1:1);
float r = rp[i][0];
stroke(175);//draw stroke for the circle
ellipse(center.x*size.x+width/2f, reversey*center.y*size.y+height/2f, r*size.x*2f, r*size.y*2f);//draw the circle
float theta = reversey*t*m+rp[i][1];
pointer.add(new PVector(r*cos(theta), r*sin(theta)));
if (m == 0) pointer.set(datas[0][0], datas[0][1]);
stroke(100,(aph<240?255:0));
line(center.x*size.x+width/2f, reversey*center.y*size.y+height/2f, pointer.x*size.x+width/2f, reversey*pointer.y*size.y+height/2f);
center.set(pointer);
}
stroke(10, 255, 10);
fill(100, 124, 255, 150);
ellipse(pointer.x*size.x+width/2f, reversey*pointer.y*size.y+height/2f, 8, 8);
if(t>=0){
posi.beginDraw();
posi.noStroke();//no stroke for the dot
posi.fill(random(255),random(255),random(255));//fill random color to the dots
posi.translate(posi.width/2f, posi.height/2f);
//posi.line(lastPos.x*size.x,lastPos.y*size.y,pointer.x*size.x,pointer.y*size.y);
posi.ellipse(pointer.x*size.x, reversey*pointer.y*size.y, 5, 5);
posi.endDraw();
image(posi, 0, 0);
transX=-pointer.x*size.x*sFactor;
transY=-pointer.y*size.y*sFactor;
}
lastPos.set(pointer);
//noLoop();
popMatrix();
}
void mouseWheel(MouseEvent X) {
float wheel = X.getCount() > 0 ? 1.05 : X.getCount() < 0 ? 1.0/1.05 : 1.0;//? is same to if else
sFactor *= wheel;
}
void keyPressed() {
if (key == 'r') {
sFactor = 1;
transX = 0.0;
transY = 0.0;
}
}
and put this in the same folder under name datas.txt
[-35.80050232466736, -53.50018619527786]
[-120.3234326095086, 38.333403210741636]
[-29.587082883301573, -33.49354222172572]
[-28.740534719381618, -7.122051704274412]
[0.1836017962610832, 6.943291446742017]
[10.55205601090014, 22.970269958046057]