// mapGridX.Y are positions in a dungeon layout called mainGrid.

solids = [0, 0]; //Create the array to store all the blocks
roomNumber = 0; //tracks which roomNumber we're in

for (mapGridX = 0 ; mapGridX < ; gridW ; mapGridX++) {
    for(mapGridY = mapGridY ; mapGridY < ; gridH  ; mapGridY++) {

        tileIndex = 0;

        // If i find a value less than 100 i populate with a specific layout,
        // the addition of layouts to below mentioned roomGrid is cut out
        if ds_grid_get(mainGrid, a ,b) < 100 {

        // A second loop to add the blocks to the world for their respective section/collection
        for (blockX = 0 ; blockX < blockGridWidth ; blockX++ ) {
                for (blockY = 0 ; blockY < blockGridHeight ; blockY++ ) {
                    // if cell value 1 is found, paint a tile or create an object.
                    if  ds_grid_get(roomGrid,blockX,blockY) = true {

                        // mapGridX and mapGridY is derived from the dungeon layout grid.
                        // This is adding a block at a real world coordinate, here, block is the unique ID of the instance.
                        block = instance_create(
                            (blockX*blockSize)+mapGridX*roomWidth,(blockY*blockSize)+mapGridY*roomHeight,oBlockTemp
                        )
                        solids[ roomNumber, tileNumber ] = block; //Put the block into the solids array for this room
                        ++tileNumber; //Increase the tileNumber so the next block is added to the array after the previous one

                        // Here i want to save the id of each block to a list/array/map/collection,
                        // so they belong to their respective section (mapGridX,mapGridY).
                        // I then want to refer to this data structure with the help of -
                        // player.x and player.y
                        // I will use these comparisons to deactivate and activate the -
                        // collection of instances.

                        }
                    }
                }

            }

            ++roomNumber; //This should be increased after each room's blocks are added. I might have got the indentation wrong

        }


    }