I am new to the entire isometric concept. I've played the games, but just the past two days have I given the idea some thought. I'm thinking of writing a small game using isometrics in OpenGL. Questions 1. Can a player move in 8 directions, or is he stuck with 4? 2. Does a player have to move in tile units, or can he move at his own pace freely? 3. When drawing things such as trees where a player might collide with the trunk, how do you handle the leaves (so they are drawn on top of the player) 4. How to handle bridges/arches (going under them)? 5. How do we handle standard collision? Do we have to add the concept of height into the equation? Stemming off from my collision question... If my player sprite is twice as tall as he is high, I won't be given much ability to move around because my head will be colliding with everything because I would be doing collision based on the rectangle of the sprite. So, if I had a hitbox to the feet and use that for collision, how can I provide coordinates for objects such as walls if they're just a tiny portion of a large texture atlas that I'm loading from by using texture coordinates? So if I have a slanted wall so to speak, when I make my map I'm assuming I have to specify coordinates for a hitbox for that wall, instead of using the walls rectangle, because that just wouldn't work right. If the head of my player runs into the bottom left corner of the walls rectangle (which has no actual texture, it's transparent) it would collide. Please offer some suggestions/insight I'm confused on the approaches I can use to achieve walking under bridges, walking behind tree leaves that might be 8 tiles high, etc. What I've gathered so far 1. I probably want a multi layered tile system, where each tile can have any number of layers 2. I probably want a system to specify the depth of each thing being drawn so I can determine the order to draw it. One last example I've run across I read an isometric article over at the world creator forums, where they use an isometric box that is supposed to look 3d. The player walks into the bottom half of it, and they collide, but if they try to walk around the top half of it, it's drawn over their feet, just as it would look if it were 3d. Now, they said they achieved this by altering the depth property of the box to say that it's drawing over the player instead of behind him. This raises the question of, what if there are two players on the screen and one is in front of the box and can collide with the bottom half, but the other play is walking behind it. If the box has 1 property for depth order and it's changed to suit the player behind it, isn't there a possibility it'll get drawn out of order for the player in front of it and it'd actually show the players head behind the box instead? Thanks for reading this very long post. I need to clear this stuff up. Maybe we can start a FAQ once all these questions are answered, because I cannot find a single place that answers them all properly, or leaves minute details out.

Thanks for the reply. This has helped me to understand it slightly better.

Three things I'm unsure of:

1. Can movable objects move on a per pixel basis? I'd really like to have this, but I'm wondering if it will add much, much more complexity.
2. Can the user rotate in 8 directions instead of the 4 basic directions?
3. What would I use for a collision box for something that isn't square? Let's say I throw a ball of fire out (hypothetically), the hitbox underneath would be a circle. Is that right? Or would I use something else?

Thanks guys. What you've said makes much more sense to me now.

Tell me if I'm far off from a proper setup. This would be a very distant view of the main execution loop.

1. Grid tiles are draw first layer down, up until there are no more, from left to right, top to bottom.
2. Collision between objects is checked (standard math here, since I'm looking at the grid at this point directly top to bottom.
3. Rotate camera to isometric style.
4. Render sprites.


This is how I envisioned it. It would make more sense for me to draw it stanard (determine exact tiles to draw at this point, and everything has normal X/Y coordinates. Then the rotation only occurs before I stick sprites on the screen and render the scene. Is this about right?

One thing that I'm still a bit hazy on is exactly how to draw sprites behind sprites and using depth properties. I really don't grasp that just yet. And I can't find a perfect tutorial on it. I've read the world creator isometric tutorials and about a dozen others, but I just don't get it. Maybe my understanding of depth indices is skewed. Here's an example of what confuses me:

Over at the world creator forum, there's a depth tutorial that has an isometric box, which occupies 2x2 tiles in real world space, but in isometric space I think it's 6 or 8, I forget which. So the goal is to change the depth if the player's hit box height is higher than half of the box. Now when that occurs it changes the depth property of the box so it's drawn after the player. But would that also mean it could screw up the depth for a player in front of it as well, so that player's upper half is accidentally drawn behind the box as well?

I just need a better understanding of these core concepts. I'm as confused as they come at this point.