Efficiently getting isometric grid positions within a bounding box

Question

I have an isometric grid system who\'s coordinates start from [0,0] in the left hand corner of t

Answer 1

Considering the regular layout of the tiles, can't you simply start from the top left corner of the selector box, hittest to find which tile, and then move along to the next tile according to how they are spaced.

For example, if your tiles are 32x16, you would start at the corner, and move along 32, then when you reach the end, go along the next row.

eg, in a strange kind of pseudocode...

var altRow = false;
var selectedTiles = [];
for (int y = selectorBox.top; y < selectorBox.top+selectorBox.height; y+=TILE_HEIGHT/2) {
    for (int x = selectorBox.left ; x < selectorBox.left+selectorBox.width; x+= TILE_WIDTH) {
        selectedTiles.add(tileAtPoint(x + (altRow ? - TILE_WIDTH/2 : 0), y);
    }
    altRow = !altRow;
}