Selecting objects on a 2D map
- by Dave
I have a object selection function by checking the mouse click and getting the relevant object.
How ever there is a rare situation where if one object is partially behind the other then both objects are in the given area so im wondering how I can make the game know which one was selected, as currently my method does not know.
This is my function that works it out:
function getobj(e){
mx = e.pageX - curleft; //mouse click x
my = e.pageY - curtop; //mouse click y
function searchSprites(sprites, x, y) {
var matches = [],
i = 0,
data = null;
for (i = 0; i < spritea.length; ++i) {
data = spritea[i].data;
if (x > data[0] && y > data[1] && x < data[2] && y < data[3]) {
var imageData = ctx2.getImageData(x, y, 1, 1);
if(imageData.data[3] !== 0){
return [spritea[i].id];
i = spritea.length;
}
}
}
}
res = searchSprites(spritea, mx, my);
bid = res[0];
if(bid === '1'){
alert('You selected the skyscraper in front!');
}else if(bid === '3'){
alert('You selected the skyscraper behind!');
}
}
Image of the map:
It keeps telling me I clicked the skyscraper behind which is not necessarily what the user is trying to do. How can I improve the accuracy of this ?
