transformations

Programming Questions

pacoruizg..

in Programming Questions • 1 year ago

Im having some problems with transformations. e.g. rotate, translate...

When Im trying to make a fractal with a limited number of transformations, I put the transformations in functions outside the draw function.

When I want one tranformation alone, and I want to make a picture, I put the transformation inside the draw function and I include noLoop().

But when I want to make one transformation alone, just because I want the coordinates origin in the center of the window, and I dont want to use noLoop() because my code will go on and on. I dont know where to make the transformation. In the setup, it doesn´t work and I dont know why.

Replies(10)

calsign

Re: transformations

1 year ago

What exactly do you mean by that?
Transformations in setup() worked fine for me...
Could you show an example of the code that isn't working or what you have tried?

pacoruizg..

Re: transformations

1 year ago

I´ll paste two codes that I see that should do the same and they doesnt:

One:

void setup(){
background (255);
size(width, length, P3D);
translate (width/2,length/2);
}

int width = 800;
int length = 800;

void draw(){

line (0,0,100,100);
noLoop();
}

The other:

void setup(){
background (255);
size(width, length, P3D);

}

int width = 800;
int length = 800;

void draw(){
translate (width/2,length/2);
line (0,0,100,100);
noLoop();
}

PhiLho

Re: transformations

1 year ago

" Transformations in setup() worked fine for me..."
Indeed, when drawing is done there.
Something often overlooked is that at the start of each draw(), all transformations are reseted.

Chrisir

Re: transformations

1 year ago

I would put all global vars before setup() and before they are used.

Also background after size

Remember with Ctrl-t you can beautify the code

You also mean height where you have length

pacoruizg..

Re: transformations

1 year ago

Thank you. So I see that when you want to program movement with a transformation at the beginning, there is no way to do that. You are mean to use the coordenates as they are defined by processing.

PhiLho

Re: transformations

1 year ago

No, you just apply the same transformation at the start of draw(): it will do the transformation on each frame.

pacoruizg..

Re: transformations

1 year ago

I've tried that but the number of times you can do a transformation is limited

PhiLho

Re: transformations

1 year ago

? See my other answer above... (about resetting transformations when starting draw()).

pacoruizg..

Re: transformations

1 year ago

Maybe I had problems with that because the transformation were not the same. To be honest now I dont remember well what was exatcly the case. I've solved the problem with this sketch, and now I have a bit of a mess with this question. I´ll re-read this post when I make a similar sketch and make myself clear. Thank you

pacoruizg..

Re: transformations

1 year ago

Now I remember. I had problems with transformations made within the draw fuction, but inside a nother function that was call recursively. I was trying to make Barnsney fern this way, and I couldn´t.