Archive for the Room Connectivity Category

The Sacred Mechanisms

Posted in Dungeon Generation, Gameplay, Graphics, Rambling Tangent, Room Connectivity, Screenshots on December 5, 2011 by sfahy

At the moment I’m working on developing the basic combat system. Combat is largely predicated on player attributes and equipment, but I want to introduce a level of more immediate strategy. By allowing the player to execute resource limited special moves during combat, the focus is shifted towards the strategy employed in each encounter, rather than just a long term min maxing of stats.

Another area I’ve been doing a lot of work on recently, and am particularly excited about, is the variety of mechanical devices that will be littered about the dungeons.

The machines can be interacted with in different ways. For example, the Translocational Impeller pictured, at it’s most basic mode of interaction, teleports the player to a random location in the dungeon. More advanced modes of interaction are possible, such as teleporting an enemy, teleporting to a specified location, charging an item with a teleport spell and so on.

The advanced modes of interaction are opened up as the player’s character and the game progresses, and allow the dungeons to gradually increase their depth of interaction without dumping complexity on new players.

The machines create the potential for emergent interaction with the dungeon itself. For example, there could be machines that flood rooms with poison gas, or heal everyone in a certain radius, or enchant a weapon according to what item is fed into it, or really do anything that can be done within the bounds of the gameplay system.

The machines will also allow the game to add twists to existing mechanics, for example a machine that suppresses spell effects in a radius, that can be modified by the player to amplify them, or to only suppress enemy effects.

The temptation is to go full on dwarf fortress mode and create a vastly complex system with incredible depth that inspires fear and trembling in all who behold it, but I think that by gradually introducing new interactions with character progress, and above all presenting a clean and context aware interface, the depth can be captured without the complexity. I think the most important rule of thumb for this and all the gameplay systems is that the player should not need a wiki in order to use this.

Once gameplay becomes tied to specific areas in the dungeon, however, the danger arises that the player will attempt and fail to navigate. For example, with the spell suppressing machine example, an obvious strategy for a combat oriented character would be to lead spell-casting enemies to it and attack them. But the player doesn’t have the same high level overview of the environment as in a traditional roguelike, and the absolute last thing I want in the game is to have the player wander aimlessly through the level, endlessly searching for a visited area.

The level generation process uses square rooms as it’s unit of synthesis, maintains a directed graph of parent to child room relationships, and only connects, combines, populates and furnishes rooms once every room has been placed.

Structure could be introduced at the graph level, for example creating a chain of rooms with one entrance and exit at either end. At the moment, every room is connected to every room that shares a wall with it, which creates an environment that is relatively easy to navigate in any direction, but that is formless – It can be difficult to identify landmarks and backtrack.

A lower level solution is to attempt to introduce texture rather than structure.

2D Perlin noise is generated across the level and used to modulate the dimensions of any rooms generated at a given location. This results in a sort of compression and rarefaction of room size across the level, with smaller rooms clustering together and creating a kind of ambient structure in the level that makes orientation easier without attempting to impose rigid patterns.

A combination of both these approaches should hopefully make directed navigation  possible without encouraging it.

On the graphics side, I’ve been experimenting with the idea of using a simple directional shadow map that would anchor the scene together without being an accurate reflection of the lighting. This would save a lot of the resource and complexity overhead of omnidirectional shadows, but the downside is that it’s horrible and it looks horrible. Horrible.

I think after a lot of intense graphics programming I feel a lot more confident that I can get a decent implementation of dual parabaloid shadow mapping into the game. Light sweeping through doorways into the darkened rooms beyond is a really cool effect and adds to the vibe of being alone in a hostile environment. Also it resonates with the torchlight effect used in so many roguelikes, and if this game is about anything, it’s about heritage.



Room Graph and Connectivity

Posted in Dungeon Generation, Room Connectivity on June 1, 2011 by sfahy

Connections between rooms were originally added between a room and the room it was spawned from, with the result that the dungeon layout mirrored the random tree method used to create the dungeon.

I’ve made the graph structure representing the rooms more robust, and have moved the door placement process further away from the level of individual tiles.

What happens now, is that basically the rooms are placed in the usual manner, and afterwards a graph structure of Room objects is used to place the doors.

Traversing a graph to connect everything up afterwards is a lot more elegant than just plugging doors in as the rooms are placed, and it opens a lot of possibilities in terms of how the rooms are connected.

At the moment, I simply connect every room to every room that is adjacent to it. This makes the dungeon very easy to traverse in any direction, which is good for wandering around gawking at things while developing it, but leaves things a bit to easy for gameplay. Still, it’s a lot better. As mentioned in an earlier post, I intend to have a system for adding connection density in a more logical manner.

The beauty of basing things off the graph structure is that it’s not tied to the dungeon generation process. The graph can be recomputed from the placed tiles very easily, and can be altered to suit gameplay goals, then handed over to the door placement code. It’s also easier to do things like, for example, having special rooms with fixed entrance and exit points, like a bridge across a pit between two doors, or a type of room that always or has a high probability of being adjacent to another specific kind.

You can see the difference between the original tree structure (top image) and the modified graph (bottom image):

(The lines changes from purple to yellow as they move from parent to child)


I’m going to be changing the architecture for the shader soon. At the moment, it’s a simple single pass with one attenuated light, exponential per-pixel fog, and diffuse, normal and specular maps.

A management system for light sources, that keeps track of them and takes care of things like culling, will need to be designed in implemented concurrently with the revised shader.

I think it would be a good idea to have a pretty well thought out shader architecture designed before hand, rather than just cramming features in and hoping it doesn’t break. I haven’t really been thinking about optimizations yet, because the priority at the moment is to get clean systems in place that wont rot and need to be refactored ten times.

I have a good idea of what I’m going to do when the frame rate starts to drop though, and if the rendering system is well designed and self contained it can be optimized later without affecting any other code.


Posted in Dungeon Generation, Room Connectivity, Screenshots, Uncategorized on May 27, 2011 by sfahy

Just a random screen dump from the game as it now, the dungeons are still bare, I don’t want to start adding “furniture” until I have a robust system for distributing it logically in appropriate rooms, as well as a good design for the game logic that underpins it’s use.

Below, you can see a directed graph showing how each room is connected. The overall connectivity forms a tree structure that fans out from the center. The next stage in dungeon generation will be to examine this graph and connect branches of the tree to each other in a manner that results in an easily navigable dungeon. I’d like to have this happen in a manner I can easily control, for example to specify the optimal cycle size in the graph and the generation system approximate this. The important thing is that I end up with a variable or small set of variables that I can tweak, because only testing will reveal what level of room connectivity will be most fun to play.