I want this object moving by mouse x and mouse y, but this code error. anybody, can help me?
That’s my code:
void setup() {
size (700,700);
}
void draw() {
background(255);
quad(mouseX+1,mouseY-5,mouseX+75,mouseY+70,mouseX+10+mouseY+80,mouseX+1,mouseY+85);
}
size (700,700);
background(255);
quad( mouseX+1,mouseY-5,
mouseX+75,mouseY+70,
mouseX+10+mouseY+80,mouseX+1,
mouseY+85, ...... );
I think that’s because you pass 7 parameters instead of 8
Please add one parameter
I like to place line breaks between parameters so you can see the 4 pairs directly
(that you pass int instead of float is not the problem I guess, I am not on my computer right now and can’t test it though)
What is parameter? Sorry, I don’t know 
and dots at the end should be filled?
Yeah, the 8 entries you pass to the function quad
are the parameters
The dots represent the 8th parameter
Parameters are separated by comma ,
The dots shall be filled, try mouseX
Thanks for the explanation, it worked! And, how to keep the shape from changing? because after I try, the shape changes
The shape changes 60 times per second when you move the mouse
There are different ways to change this
For example you store your parameters
in variables or a list when you press a mouse button
You can also say
if(mousePressed)
noLoop();
if(keyPressed)
loop();
Both in draw() function
Oh I see, thanks a lot! I will try it
you can use a list of floats:
float[] list = new float[8];
void setup() {
size (700, 700);
}
void draw() {
background(255);
list = new float[8];
list[0]=mouseX+1;
list[1]=mouseY-5;
list[2]=mouseX+75;
list[3]=mouseY+70;
list[4]=mouseX+10+mouseY+80;
list[5]=mouseX+1;
list[6]=mouseY+85;
list[7]=mouseX;
drawQuad(list);
}
void drawQuad(float[] list_) {
quad(list[0], list[1],
list[2], list[3],
list[4], list[5],
list[6], list[7]
);
}
Let’s put the storing in a function too
float[] list = new float[8];
void setup() {
size (700, 700);
}
void draw() {
background(255);
storeQuad();
drawQuad(list);
}
// ---------------------------------------------------------
void storeQuad() {
list[0]=mouseX+1;
list[1]=mouseY-5;
list[2]=mouseX+75;
list[3]=mouseY+70;
list[4]=mouseX+10+mouseY+80;
list[5]=mouseX+1;
list[6]=mouseY+85;
list[7]=mouseX;
}
void drawQuad(float[] list_) {
quad(list[0], list[1],
list[2], list[3],
list[4], list[5],
list[6], list[7]
);
}
Next version
You can store forms/quads in a list on mouse click
float[] list = new float[8];
// Two parallel ArrayLists
ArrayList<float[]> listOfQuads = new ArrayList();
ArrayList<Integer> listOfColors = new ArrayList(); // for Color
void setup() {
size (700, 700);
}
void draw() {
background(255);
int i=0;
for (float[] floatList : listOfQuads) {
fill(listOfColors.get(i));
drawQuad(floatList);
i++;
}//for
noFill();
storeQuad();
drawQuad(list);
}//func
// ---------------------------------------------------------
void mousePressed() {
listOfQuads.add(copyList(list));
listOfColors.add(color(random(255), 0, 0));
}
float[] copyList(float[] list_) {
float[] l1=new float [8];
int i=0;
for (float floatValue : list_) {
l1[i]=floatValue;
i++;
}
return l1;
}
void storeQuad() {
list[0]=mouseX+1;
list[1]=mouseY-5;
list[2]=mouseX+75;
list[3]=mouseY+70;
list[4]=mouseX+10+mouseY+80;
list[5]=mouseX+1;
list[6]=mouseY+85;
list[7]=mouseX;
}
void drawQuad(float[] list_) {
quad(list_[0], list_[1],
list_[2], list_[3],
list_[4], list_[5],
list_[6], list_[7]
);
}
Code a bit simplified
// draws quads according to mouse pos; click mouse to store the current quad.
float[] list = new float[8];
// Two parallel ArrayLists
ArrayList<float[]> listOfQuads = new ArrayList();
ArrayList<Integer> listOfColors = new ArrayList(); // for Color
// ---------------------------------------------------------
void setup() {
size (700, 700);
}
void draw() {
background(255);
// draw old quads
drawExistingQuads();
// the current quad
noFill();
storeQuad();
drawQuad(list);
}//func
// ---------------------------------------------------------
void mousePressed() {
// store current quad
listOfQuads.add(list.clone()); // using clone() here
listOfColors.add(color(random(255), 0, 0));
}
// ---------------------------------------------------------
void drawExistingQuads() {
// draw old quads
int i=0;
for (float[] floatList : listOfQuads) {
fill(listOfColors.get(i));
drawQuad(floatList);
i++;
}//for
}//func
void storeQuad() {
// current quad
list[0]=mouseX+1;
list[1]=mouseY-5;
list[2]=mouseX+75;
list[3]=mouseY+70;
list[4]=mouseX+10+mouseY+80;
list[5]=mouseX+1;
list[6]=mouseY+85;
list[7]=mouseX;
}
void drawQuad(float[] list_) {
// draw the quad indicated by list_
quad(
list_[0], list_[1],
list_[2], list_[3],
list_[4], list_[5],
list_[6], list_[7]
);
}
//
Minor changes
// draws quads according to mouse pos; click mouse to store the current quad.
// the current quad
float[] list = new float[8];
// Two parallel ArrayLists store the quad
ArrayList<float[]> listOfQuads = new ArrayList();
ArrayList<Integer> listOfColors = new ArrayList();
// ---------------------------------------------------------
void setup() {
size (700, 700);
}//func
void draw() {
background(255);
// draw old quads
drawExistingQuads();
// the current quad
noFill();
storeQuad(list);
drawQuad(list);
}//func
// ---------------------------------------------------------
void mousePressed() {
// store current quad
listOfQuads.add(list.clone());
listOfColors.add(color(random(255), random(255), random(255)));
}//func
// ---------------------------------------------------------
void drawExistingQuads() {
// draw old quads - using both ArrayLists
int i=0;
for (float[] floatList : listOfQuads) {
fill(listOfColors.get(i));
drawQuad(floatList);
i++;
}//for
}//func
void storeQuad(float[] list_) {
// current quad
list_[0]=mouseX+1;
list_[1]=mouseY-5;
list_[2]=mouseX+75;
list_[3]=mouseY+70;
list_[4]=mouseX+10+mouseY+80;
list_[5]=mouseX+1;
list_[6]=mouseY+85;
list_[7]=mouseX;
}//func
void drawQuad(float[] list_) {
// draw the quad indicated by list_
quad(
list_[0], list_[1],
list_[2], list_[3],
list_[4], list_[5],
list_[6], list_[7]
);
}//func
//
You original code:
mouseX+10+mouseY+80
Did you intend to add these?
If you change the + in the middle to a , you have your 8 parameters and the shape moves with mouse but does not change.
:)
thanks again for the help! I don’t know what to repay you with other than thanks. hope your days are fun! 
Thanks for the explanation! I will try it
Maybe that what glv said is what you really meant.
Then I misunderstood you. nvm
You can also use rect () and rectMode(CENTER);
no problem, thank you!