draw out a rectangle

Programming Questions

youplop

in Programming Questions • 1 year ago

Hello.
I would like to draw a rectangle, but fill it outside.
Like this: (background is white)

Draw four rectangles is the unique solution?
Thanks

Replies(6)

asimes

Re: draw out a rectangle

1 year ago

In that particular case it would be easiest to make a yellow background and then draw the rectangle.

amnon.owed

Re: draw out a rectangle

1 year ago

The undocumented, the mysterious, the unsupported... don't use it! BREAKSHAPE!

Code Example

void setup() {
size(400, 400);
smooth();
}
void draw() {
background(255);
fill(255, 0, 0);
ellipse(width/2, height/2, 200, 200);
fill(255, 255, 0);
beginShape();
vertex(0, 0);
vertex(width, 0);
vertex(width, height);
vertex(0, height);
vertex(0, 0);
breakShape();
vertex(mouseX-100, mouseY-100);
vertex(mouseX-100, mouseY+100);
vertex(mouseX+100, mouseY+100);
vertex(mouseX+100, mouseY-100);
endShape(CLOSE);
}

asimes

Re: draw out a rectangle

1 year ago

Wow, that's REALLY handy. Why isn't that supported?

amnon.owed

I don't know. It's been in Processing for years and it's still in the 2.0 alphas, but I guess it has never been fully developed (only works in JAVA2D) and also never made it into the reference. In the source and javadocs it still says...

This feature is in testing, do not use or rely upon its implementation

But it can still be useful in some cases. Works quite well here I think.

tfguy44

Re: draw out a rectangle

1 year ago

// breakShape()??? You're crazy! Just use my function...

void setup(){
size(100,100);
}
void draw(){
background(255);
outer_rect( 20,30,50,40, color(0), color(200,200,0) );
}
void outer_rect( float x, float y, float w, float h, color strokeCol, color fillCol ){
pushStyle();
noStroke();
fill( fillCol );
rect(0, 0, x, height);
rect(0, 0, width, y);
rect(x+w, 0, width-x-w, height);
rect(0, y+h, width, height-y-h);
noFill();
stroke( strokeCol );
rect(x, y, w, h );
popStyle();
}

youplop

Re: draw out a rectangle

1 year ago

Hello, thanks a lot!!
So:
@ asimes: Of course it was an example, the goal is to fill the screen, exept a area.
@ amnon.owed: breakshape is just magic, wow!! your example is nice, I wiil keep it for fun :)
But... do not use or rely upon its implementation.
So that why I'm going to use the tfguy44 's function, which seems a good way for my program.
Because you I just discovered the push/popStyle function, very usefull :)
Thanks again, friends!

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