I've been trying to understand fixed time step game loops for about 3 weeks and I'm still having trouble understanding it. I've read http://lspiroengine.com/?p=378 http://gafferongames.com/game-physics/fix-your-timestep/ and http://www.koonsolo.com/news/dewitters-gameloop/ multiple times and I still can't wrap my head around it exactly. I understand that we want to render as fast as possible as well as updating the game logic at regular intervals. What I don't understand is why the interpolation value is used in the rendering function instead of the update logic function. Also, what would be the time that I would use to do my actual logic updates? Would it be the dt time (interpolation time) or what? If someone can do a mock up in paint to help me visually see how everything connects I would GREATLY appreciate it. I'm driving myself crazy trying to get this under my belt. Another problem I was having was my timer integer was "overflowing".
(I had a tough time understanding gafferon's tutorial. deWitter and Spiro I understood better)