What's up everybody?

Ok, so i am making a top-down 2(.5)D game. My "floor" tiles are stored in a WxH array (not tiles, but their id's). When I want to render them, I use two fors (y and x) get the texture for that tile id and render it at x * Tile.TILE_SIZE (int constant). To optimize the algorithm, i calculate a start and end x and y based on camera's position (a float transformed to a integer), and render only tiles that are on the screen.
Problem:
The problem is that when i move the camera (using a calculated delta -- huge decimal number) i get a visual bug: 1 pixel gap between random rows of tiles (only horizontal gap). My assumption is that the problem is caused by that float -> integer transformation.
Could anyone tell me how can i fix this problem? Also, how can i avoid this type of problems?
Thanks!
LE: Here's one picture of what is happening.
