# Silgen

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1. ## A* - Keeping track of nodes

Ultramailman - the white path overwrites the orange path, and the open list just outlines the orange block.
2. ## A* - Keeping track of nodes

Ah I understand what you are saying - my mistake. I disabled that type of movement to prevent it going through walls that are only one block thick - guess I'll need to revise that then.
3. ## A* - Keeping track of nodes

Surely it would have had to make the diagonal movement just before reaching the point though?
4. ## A* - Keeping track of nodes

I've finished implementing what I believe to be an A* algorithm in some rather heinous code. I hope to try out binary heaps when I revisit this. These are some images showing it in action. Blue representes an obstacle tile, orange a closed list square (explored) and the white line is the final path. Does this look correct? It moves towards the obstacle, then fills in back toward the starting point, until it can get around the obstacle, then resumes.
5. ## A* - Keeping track of nodes

My code is pretty dirty at the moment - unsorted lists for open/closed, and a 2d array for the map. The path is just a singly linked list of nodes.
6. ## A* - Keeping track of nodes

Working on my A* implementation - Mostly working fine, but I'm having difficulties in updating the g values of nodes. When I look at the neighbours of a given node - in order to check whether or not the g value is an improvement on the current node's g value, I have to search both lists, comparing the x/y coordinates of the current node, with each node in the lists. This seems over complicated. What is a good way of keeping track of the neighbours of a given node?
7. ## A* Implementation Question

Okay - then perhaps my question should have been - which representation of the search space will make running the A* algorithm on it easiest? What method is most commonly used?
8. ## A* Implementation Question

I have been reading about the A* algorithm recently, and I want to implement it myself to make sure that I fully understand it. What is the best way of representing the map that will be searched? Array? A tree of some kind?
9. ## Game States

Thankyou for all of your replies. I've tried to take into consideration the points raised in the responses, and I've written a simple program to test this out. I was hoping you guys could give me some feedback - or some general pointers etc. Extract from cState.h [source lang="cpp"]class cState { private: static cState* currentState; static bool isRunning; public: virtual void enter() = 0; virtual void update() = 0; virtual void leave() = 0; void setCurrentState(cState*); void updateCurrentState(); void exit(); }; class cStateA : public cState { public: cStateA(cState*); ~cStateA(); void enter(); void update(); void leave(); };[/source] Extract from cState.cpp [source lang="cpp"]#include "cState.h" //--- cState* cState::currentState; bool cState::isRunning = true; void cState::setCurrentState(cState* target) { currentState = target; } void cState::updateCurrentState() { while(isRunning) { currentState->update(); } } void cState::exit() { isRunning = false; } //--- cStateA::cStateA(cState* caller) { //Clean up after the caller state and initialise the current one if(caller) caller->leave(); setCurrentState(this); enter(); } cStateA::~cStateA() { std::cout << ">> Destructor called for A" << std::endl; } void cStateA::enter() { std::cout << ">> Entering State A" << std::endl; } void cStateA::update() { std::cout << "Enter desired state: "; if(getch() == 'b') { setCurrentState(new cStateB(this)); } } void cStateA::leave() { std::cout << std::endl << ">> Leaving State A" << std::endl; delete this; }[/source]
10. ## Game States

Going back to basics and writing really simple games (tic-tac-toe, currently) but trying to use a good, clean OO structure. All states are derived from a base class cState: [source lang="cpp"]class cState { public: virtual void enter() = 0; virtual void update() = 0; virtual void leave() = 0; };[/source] The code below is for the state manager [source lang="cpp"]void cGame::changeState(cState* targetState) { currentState->leave(); currentState = targetState; currentState->enter(); }[/source] I was thinking of putting each state in its own file, but this means I will need to pass a pointer to the state manager (so that the state manager knows when to switch states) and also an inclusion for all of the header files for the states that it can transition to. This sounds messy. Is there a better way of doing it?
11. ## Uphill Struggle

I don't have anywhere near as much experience with game development as I would like to, and I have an ever increasing amount of school work to be completing, leaving me less time to work on my projects. Apart from feeling that the platformer I was working on is far more complicated than it should be, I'm just not getting anywhere with it. Due to my entity management system, I'm struggling to fix bugs with the collision detection and movement without breaking something else. I feel like I've either bitten off more than I can chew at this point, or am simply over complicating things. I feel that I've hit a dead end with this current project, and my motivation has plummeted, ushering in a lot of self doubt about my own ability, which may or may not be accurate. This won't be the first time I've bailed on something like this, and honestly it just feels like complete failure. I'm not really sure what to do - should I just go back and work on something simpler, or what?
12. ## More Collision Problems

I have recently returned to my platformer, and am having more collision woes. I am moving the player by its velocity, iterating through intersected solid objects looking for the minimum penetration axis, and reversing the movement. However when in mid air, and pushing against a wall - it gets stuck and vibrates. Has anyone had similar problems?
13. ## FSMs in Platformers

Are you working on a platformer? Or maybe a 2D RPG type of game? If you are working on a platformer, do you not need states for jumping and being on the ground? Or could you just represent them using a boolean variable? I like the idea of using a state machine for the animations - what I was actually going to do was just set the animations in the walk state, or in the run state etc. - but this seems like a better solution.
14. ## A Simple Presentation for Beginners

Lots of great information there. Personally I like to see things clearly mapped out. Perhaps you could map out the path you took from beginner to where you are now, or perhaps a suggested path that goes from knowing nothing about game programming to making something a bit more interesting. Like - learn python -> learn pygame -> make a pong clone -> make tetris etc. After all - learning to program games is accomplished by programming games.
15. ## FSMs in Platformers

I have got my platformer working in a very basic fashion: entity/tile management system, collision, movement, collectible/dangerous items, camera etc. I have a long list of things that I would like to start adding/improving - and I think a state system for the entities would be a good place to start. My thinking was that this would simplify handling different kinds of behaviour - but also that I could link animations in with states. However I am unsure of exactly how to structure this. I was considering states like grounded, jumping, underwater, dead - and then having nested states (moving left, moving right, stationary.) How have you guys handled this in the past/would you handle this?