Ingame Mini Map

[pancake0Dean]

Ahoy!

So during beta testing my game I received a bunch of requests for a mini map (a la GTA). At first I ignored the requests because I have close to no idea as my first attempt at one went horribley wrong. Anywhoo I've realised it would come in quiet handy. I've searched about a bit and found nothing terrebley helpful. Anyone care to explain to me how to make one?

My overall map is 1748 by 1472 if that helps?

Help :)

[pancake0Dean]

Ignore the spelling mistakes and nonsenselessness. =D

[DawnOfDusk]

ok well then just scale down the map to a certain ratio, redraw a loose representation of the overworld map, and by using the same numbers as the ratio, plug in an equation to make the mini map move also.

Say, your map was 12x9 k? (just picture)

then you mini map could be something like 4:3.
And to make your mini map move, you would do something along the lines of...

//After alot of shit

if(Key.isDown(w/e)){
character._x += _root.speed.
Minimap._x += (1/3)*_root.speed.
}

That should help get you started.

[pancake0Dean]

Still not quite got it. I think it's because I'm shit at maths.

[gankro]

be more specific, there are many styles of mini maps, do you want an entire map visible at once or just a portion at a time? if it's the portion then it is simple as using a mask and changing it's coordinates at a scaled rate as the real maps I.E:

if your mini map = 1/10 the size of the real map, it will move 1/10 as fast as it.

[Wurmy]

Here's what I would do for a perfectly accurate minimap.

Lets say you have a map that is 10 units by 10 units (what the units are doesn't matter, this is an example). You have a minimap that is 1 unit by 1 unit.

So the minimap is 1 tenth the size of the real map. What you do next is get the position of the player relative to the map (the 10 by 10 map)

Then divide the x by 10, and the y by 10. Those are your relative coordinates to use in the minimap!

[ssjskipp]

Easiest thing to do:

Bismapdata.draw();

Useful. Hint: Scaling matrix.

AS3:

//Create minimap BMD
var minimap:BitmapData = new BitmapData(200, 200, true, 0);
//Create the holder
var bmp:Bitmap = new Bitmap(minimap);
//Attach it
stage.addChild(bmp);
//If you have a level MC (some display object containing JUST terrain), replace stage
//Make sure you don't include the minimap itself in the draw (hence it attaching to stage, not root)
//You'll have to do more translating + scaling with the matrix to make it fit right if 0,0 isn't top left
var target = root;

function renderMap() {
	//Set scales
	sX = minimap.width/target.width;
	sY = minimap.height/target.height;
	//Preserve square-minimap scaling
	sX = sX > sY ? sY : sX;
	sY = sY > sX ? sX : sY;
	//Create draw matrix
	var scale:Matrix = new Matrix();
	//Scale matrix
	scale.scale(sX, sY);
	//Clear minimap + fill with a transparent color (makes it easier to see edges of minimap)
	minimap.fillRect(minimap.rect, 0x33000000);
	//Draw new minimap, using scale values
	minimap.draw(target, scale);
}
//Set an interval to re-render minimap every 30ms (= to 30fps, 1fps = 1000ms/f, 30fps = 30ms/f)
setInterval(renderMap, 30);

[DawnOfDusk]

At 7/19/08 08:47 PM, ssjskipp wrote: Easiest thing to do:

How was that easy? lmao. Good Stuff, anywho.

I love how my idea is the same as everyone elses except for yours, but urs is good.
Good stuff.

[ssjskipp]

It's easy because it clones the EXACT map -- I mean, yeah, if you don't know bitmap data and such, it's a little tough, but I mean -- I typed that into here, then quickly tested + formatted, then copied back in like, 2 minutes.

Also, it requires 0 work except for copy + paste (you don't need to re-draw a map). And if you were clever, you can write an edge finding script, and turn ANY map into edges-only (removes terrain and stuff). For that, convolution filter!