• Announcements

    • khawk

      Download the Game Design and Indie Game Marketing Freebook   07/19/17

      GameDev.net and CRC Press have teamed up to bring a free ebook of content curated from top titles published by CRC Press. The freebook, Practices of Game Design & Indie Game Marketing, includes chapters from The Art of Game Design: A Book of Lenses, A Practical Guide to Indie Game Marketing, and An Architectural Approach to Level Design. The GameDev.net FreeBook is relevant to game designers, developers, and those interested in learning more about the challenges in game development. We know game development can be a tough discipline and business, so we picked several chapters from CRC Press titles that we thought would be of interest to you, the GameDev.net audience, in your journey to design, develop, and market your next game. The free ebook is available through CRC Press by clicking here. The Curated Books The Art of Game Design: A Book of Lenses, Second Edition, by Jesse Schell Presents 100+ sets of questions, or different lenses, for viewing a game’s design, encompassing diverse fields such as psychology, architecture, music, film, software engineering, theme park design, mathematics, anthropology, and more. Written by one of the world's top game designers, this book describes the deepest and most fundamental principles of game design, demonstrating how tactics used in board, card, and athletic games also work in video games. It provides practical instruction on creating world-class games that will be played again and again. View it here. A Practical Guide to Indie Game Marketing, by Joel Dreskin Marketing is an essential but too frequently overlooked or minimized component of the release plan for indie games. A Practical Guide to Indie Game Marketing provides you with the tools needed to build visibility and sell your indie games. With special focus on those developers with small budgets and limited staff and resources, this book is packed with tangible recommendations and techniques that you can put to use immediately. As a seasoned professional of the indie game arena, author Joel Dreskin gives you insight into practical, real-world experiences of marketing numerous successful games and also provides stories of the failures. View it here. An Architectural Approach to Level Design This is one of the first books to integrate architectural and spatial design theory with the field of level design. The book presents architectural techniques and theories for level designers to use in their own work. It connects architecture and level design in different ways that address the practical elements of how designers construct space and the experiential elements of how and why humans interact with this space. Throughout the text, readers learn skills for spatial layout, evoking emotion through gamespaces, and creating better levels through architectural theory. View it here. Learn more and download the ebook by clicking here. Did you know? GameDev.net and CRC Press also recently teamed up to bring GDNet+ Members up to a 20% discount on all CRC Press books. Learn more about this and other benefits here.
Sign in to follow this  
Followers 0
yop123

Pathfinding for large 3D worlds with complex buildings

2 posts in this topic

Hi,

I am thinking about trying to implement a prototype of pathfinding that could work with large 3D worlds (a huge terrain) which contains obstacles (trees) and complexe buildings (with a lot of stairs, ladders, and can have a lot entrance doors (see the picture))

I have found a lot of informations for the plannar case but not when there is an [u]huge terrain[/u] [b]AND[/b] a lot of [u]complexe buildings[/u] (stairs and ladders at different levels)


I already did a A* on the 2D ground (and I can handle terrain obstacles) but I have no idea how to extend the pathfinding to take into account complexe buildings which have complexe connections.
Moreover, because i want to have a huge map, i do not want to store too much precomputed paths/nodes.


-So, how is problem is (well) handled in games ? And you, how do you do (or would you do) ?

-Is there one ultime strategy or do I have to perform two different pathfinding and link the solutions ? (for instance A* + navigation mesh?)

-If it is the case, have you some advises about how to make the link between the different strategies and about the choice of the algorithms ?

-Are there some solutions from robotic which could work in real time with a lot of instances ?

-How do you deals with "action required path" like "use the ladder" or "jump over the hole" or "try to climb the wall" ?


Thanks you all
0

Share this post


Link to post
Share on other sites
2 things... remember that pathfinding happens over a graph network -- not over a plane. Therefore, you can have multiple levels of buildings that are physically above each other but are separate graph spaces connected by something (stairs, elevator, etc.). Do NOT confuse the physical space with the graph space.

Second, hierarchical A* is a lifesaver here. When you travel, you don't plan every move on the same level of detail. You think about navigating from building to building, then from floor to floor, then from room to room, and then across the room. So when leaving the house to go to work, you aren't planning to walk around the table in the middle of your office. You aren't even really thinking about moving from the stairs to the lobby, down the hall, and into your office. You are ONLY thinking about getting from your house to the office. Worry about the details later. That cuts down your search space based on the granularity needed. There are a lot of resources on hierarchical A* out there.
0

Share this post


Link to post
Share on other sites
You have to remember that A* is a graph based path-finding algorithm. There's nothing limiting it to 2D. That means stairs, climbing, jumping, etc are fine. The key is how to set up that graph. A 2D grid-based approach sets up a different graph for A* than a navmesh does. In general I'd say that navmeshes yield better results, but they're harder to set up. Some navmesh implementations handle stairs fine - they just need to know how high a step you can climb and how steep a slope. They figure the rest out. That's one automatic connectivity criteria - what can you climb? Similarly you could allow climbing over chest-high obstacles, but just set the cost a bit higher so the character prefers to walk up stairs rather than bypass them. Special actions such as jumping... get more difficult. Walking up and down stairs can be done at any speed and is easily reversible. Jumping needs to take all sorts of physics into account. Are you running fast enough to make the jump? What about the height difference between where you are and your destination? Is there a chandelier or rock that you'd hit your head on if you jumped? That will require a lot of thinking on your part.
0

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0