show text on a location on the screen

Programming Questions

Jeanne

show text on a location on the screen

in Programming Questions • 1 year ago

On an field of 50 horizontal lines and 50 vertical lines,

I need the mouse to show a text when its on one a the cross points.

There are a lot of solutions with roll over but then you need buttons underneath.

How can you build this, any tips?

Replies(3)

dr.mo

Re: show text on a location on the screen

1 year ago

this provides you with a function ' IsMouseOver' to do the check. all you need to work our is where the lines cross i.e. the coordinates in your window and set them in that function. so in the example below you want to modify crossingX and crossingY to be that point. i've just assumed it's in the centre of the screen.

int crossingX;
int crossingY;
float rad;
void setup()
{
size(200, 200);
//work out where my lines cross
crossingX = width/2;
crossingY = height/2;
//set here how far can the mouse be away from that point and still
//trigger the hotspot
rad = 20;
}
void draw()
{
background(0);
stroke(255);
//verticlal line
line(width/2,0,width/2,height);
//horizontal line
line(0,height/2,width,height/2);
if(IsMouseOver(mouseX,mouseY,crossingX,crossingY,rad))
{
//draw circle - you probably want to change this and put some text display here
fill(255,0,0,128);
ellipse(crossingX,crossingY,2*rad,2*rad);
}
}
//this function checks if your mouse pointer (at position mx and my)
//is inside a circle with radius rad and centred at your hot spot point px and py
//you can use this for any mouse over checks in your program!
boolean IsMouseOver(int mx, int my, int px, int py, float rad)
{
float dx = mx - px; //distance of mouse from centre in x dir
float dy = my - py; //distance of mouse from centre in y dir
//use pythagoras theorem to see if the mouse is inside or outside of our hot spot circle
if(dx*dx + dy*dy < rad*rad)
{
return true;
}
else
{
return false;
}
}

Jeanne

Re: Re: show text on a location on the screen

1 year ago

I think I can make it work now

Thanks a lot

;-)

PhiLho

Re: show text on a location on the screen

1 year ago

You must know the coordinates of the lines (x position for vertical ones, y position for horizontal ones), either by storing them in an array, or, more probably, by computing them on the fly if they are at regular intervals.
Then it is just a matter of checking mouseX & mouseY against these coordinates. If mouseX matches one of the x positions, and mouseY matches one of the y ones, then you are over a crossing.

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