all. I need to create some map that will be moving in cycle. How can i do this.
For some parts of my game i use very long tmx map.
But now i need to repeat some texture forever.
for tmx map i use :
self.tiledMap =[CCTMX tiledMapWithTMXFile:#"mapLOng1.tmx"];//map width=device width map height=20000 px
moveMapAction = [CCMoveBy actionWithDuration:300.0 position:ccp(0,-20000)];
[self.tiledMap runAction:moveMapAction];
it's work perfect
but how can I repeat this map? (when map end start map from beginning)
Thanks
You should check out Ray's tutorial on How to Make a Space Shooter. I think it has just the thing you're looking for.
http://www.raywenderlich.com/3611/how-to-make-a-space-shooter-iphone-game
Related
So I'm working on a project for a class and I'm still trying to figure out how to go about doing something.
I am making a game where there is a board of squares or hexagons, they are either black or white, each being a state of being "Flipped", and when you click one square/hexagon, it flips all the adjacent shapes too.
Here is an image of what I am aiming to create.
Assignment images
I have gotten it running with squares, but now I need to do it with Hexagons. With the squares I registered a mouseclick as being within a square parameters of the x and y location of the click, and the state changes are assigned to a list of values assigned similarly to how the shapes were assigned within a list.
I will include a quick recording of the square program running in a folder I'm going to link.
Now, I believe I can't apply this kind of system to hexagons since they don't really line up like the squares did.
So how would I go about making a click register within a single hexagon on a grid? I have already drawn out the grid, but I am stuck on what to do to register a click to allow a hexagon to change it's state from un-flipped to flipped. I'm pretty sure I know what to do for the state change itself, but I don't know how to go about this, would it involve something with making a separate Class or something? I would appreciate any help with this.
I'll put a dropbox link here for the progress I made so far, and a pdf manual for graphics.py.
Dropbox: Python files
You can view the python code in your web-browser with dropbox too, I don't really want to fill this page pull of an entire thing of code..
Any help and feedback would be wonderful, thank you c:
so, TL;DR: How do you register a click within a polygon shape in python that allows it to change a value (within a list?) and change its visual appearance.
Just for the general side of your question, you can use a test to check if a point (x, y) is inside a polygon (formed by a list of x, y pairs).
Here's one such solution: http://www.ariel.com.au/a/python-point-int-poly.html
# determine if a point is inside a given polygon or not
# Polygon is a list of (x,y) pairs.
def point_inside_polygon(x,y,poly):
n = len(poly)
inside =False
p1x,p1y = poly[0]
for i in range(n+1):
p2x,p2y = poly[i % n]
if y > min(p1y,p2y):
if y <= max(p1y,p2y):
if x <= max(p1x,p2x):
if p1y != p2y:
xinters = (y-p1y)*(p2x-p1x)/(p2y-p1y)+p1x
if p1x == p2x or x <= xinters:
inside = not inside
p1x,p1y = p2x,p2y
return inside
This can be used in a way that is quite symmetrical to your drawing code, as you also form polygons in the same way for drawing as you would to test to see if the cursor is inside a hex.
You can modify the above implementation also to work with this Point type you are using to draw the polygons.
The rest you should be able to figure out, especially considering that you managed the input handling and drawing for the square grid.
I'm creating a game in Qt in c++, and I store every coordinate of specific size into a vector like :
std::vector<std::unique_ptr<Tile>> all_tiles = createWorld(bgTile);
for(auto & tile : all_tiles) {
tiles.push_back(std::move(tile));
}
Each level also has some healthpacks which are stored in a vector aswell.
std::vector<std::unique_ptr<Enemy>> all_enemies = getEnemies(nrOfEnemies);
for(auto &healthPackUniquePtr : all_healthpacks) {
std::shared_ptr<Tile> healthPackPtr{std::move(healthPackUniquePtr)};
int x = healthPackPtr->getXPos();
int y = healthPackPtr->getYPos();
int newYpos=checkOverlapPos(healthPackPtr->getXPos(),healthPackPtr->getYPos());
newYpos = checkOverlapEnemy(healthPackPtr->getXPos(),newYpos);
auto healthPack = std::make_shared<HealthPack>(healthPackPtr->getXPos(), newYpos, healthPackPtr->getValue());
healthPacks.push_back(healthPack);
}
But know I'm searching for the fastest way to check if my player position is at an healthpack position. So I have to search on 2 values in a vector : x and y position. Anyone a suggestion how to do this?
Your 'real' question:
I have to search on 2 values in a vector : x and y position. Anyone a
suggestion how to do this?"
Is a classic XY question, so I'm ignoring it!
I'm searching for the fastest way to check if my player position is at
an healthpack position.
Now we're talking. The approach you are using now won't scale well as the number of items increase, and you'll need to do something similar for every pair of objects you are interested in. Not good.
Thankfully this problem has been solved (and improved upon) for decades, you need to use a spacial partitioning scheme such as BSP, BVH, quadtree/octree, etc. The beauty of the these schemes is that a single data structure can hold the entire world in it, making arbitrary item intersection queries trivial (and fast).
You can implement a callback system. Then a player moves a tile, fire a callback to that tile which the player is on. Tiles should know its state and could add health to a player or do nothing if there is nothing on that tile. Using this technique, you don`t need searching at all.
If all_leathpacks has less than ~50 elements I wouldn't bother to improve. Simple loop is going to be sufficiently fast.
Otherwise you can split the vector into sectors and check only for the elements in the same sector as your player (and maybe a few around if it's close to the edge).
If you need something that's better for the memory you and use a KD-tree to index the healtpacks and search for them fast (O(logN) time).
Im using SFML 2.1 for graphics and my game structure follows SFML book quite closely (SceneGraph implementation etc)
My world consists mostly of characters (around 1-400, moving around) and tiles (3600, stationary) and I'll check for collisions everytime something moves
In worst case scenario with ~400 characters moving around and ~3600 tiles, I have 4000 possible entities with collision and 800 collision check calls (separate X and Y movement) each frame -> 3.2M collision checks in total.
Almost all my entities have size of 16x16 pixels and I've been looking into implementing either quadtree or simpler grid for collision detection, which should bring number of collision checks down quite a bit. By grid I mean http://conkerjo.wordpress.com/2009/06/13/spatial-hashing-implementation-for-fast-2d-collisions/
But I have no idea how I should implement simple grid for example. All help is welcome. There's propably even a lot better ways to bruteforce this.
Entity update step.
I do X/Y-axis movement separately. Because I want to slide against entities when colliding diagonally.
Move entity horizontally
Check and handle collisions
Move entity vertically
Check and handle collisions
Repeat 1-4 for all entities
.
void Entity::updateCurrent(sf::Time dt, CommandQueue& commands)
{
setPreviousPosition(getPosition());
move(sf::Vector2f(mVelocity.x, 0) * dt.asSeconds());
handleCollision();
setPreviousPosition(getPosition());
move(sf::Vector2f(0, mVelocity.y) * dt.asSeconds());
handleCollision();
}
I've had the following problem before when I tried to handle both X and Y movement at the same time:
I had no idea if I should reset X or Y position after collision.
Collision handling.
I'll handle collisions only when entities are moving (currently only character entities, later projectiles and some special tiles)
if entity is tile -> do nothing
if entity is character -> check collisions with characters and tiles and reset movement if collision happened
.
void Entity::handleCollision()
{
if (getCategory() & Category::Tile)
return;
if (getCategory() & Category::Character)
{
std::set<SceneNode::Pair> collisionPairs;
checkCollision(*mSceneGraph, collisionPairs);
for (SceneNode::Pair pair : collisionPairs)
{
if (matchesCategories(pair, Category::Character, Category::NonPassableCharacterOrTile))
{
resetPreviousPosition();
break;
}
}
}
}
I'll check collision simply by using SFML's intersects-function. This is propably good enough for this?
bool collision(const SceneNode& l, const SceneNode& r)
{
return l.getBoundingRect().intersects(r.getBoundingRect());
}
If I were to implement grid or quadtree for collision detection, when should I populate it, when update? Should I update it every time I move one entity, or should I try to come up with a way to move all entities at once, then build grid/quadtree and only after that try to handle all collisions.
So my questions are: (1) In this scenario how and when should I do collision handling? My current implementation works, but I think I do it too often and all examples I looked into grids/quadtrees assumed that I do first all movement and do collision detection and handling after.
and (2) When do I clear/populate/update my grid/quadtree. For example if I have 3600 tiles and 3 moving characters. Should I seek for entity each time one moves in the grid and try to move it to different grid cell / tree branch?
Edit:
What I'll propably try next unless anyone gives better advice
Updated update step.
Is this smart or in anyway reasonable way to do this?
Remove entity from grid/quadtree
Move entity horizontally
Add entity to grid/quadtree
Check and handle collisions
Remove entity from grid/quadtree
Move entity vertically
Add entity to grid/quadtree
Check and handle collisions
Repeat 1-8 for all entities
.
Entity::move()
{
grid.getCell(getPosition()).remove(this);
... move x
grid.getCell(getPosition()).add(this);
... if collision, reset x
grid.getCell(getPosition()).remove(this);
... move y
grid.getCell(getPosition()).add(this);
... if collision, reset y
}
Entity::checkCollision()
{
list<Entity*> possibleColliders;
possibleColliders = grid.getEntitiesInRectangle(x - s, y - s, x + s, y + s);
... now only check collision against possibleColliders
}
I think a quadtree would work quite well and since it will be standalone there's really no issue in adding it into your current system.
The important question you've ask is probably, when to populate and update the quadtree. I think this largely depends on your use case. Since you have around 400 characters that can change position for each frame, it probably wouldn't make a lot of difference if you try to move the nodes in the quadtree or if you fully rebuild the quadtree. Which is really more performant depends on your algorithm and datastructure, which would need some performance testing.
In this tutorial, they also suggest to rebuild the quadtree every frame iteration.
For the "how to fix collision handling" you'll need to provide more information/a separate SO question, since it's not that clear what the issue is.
I have an array - 2D(100 x 100 in this case) with some states limited within borders as shown on picture:
http://tinypic.com/view.php?pic=mimiw5&s=5#.UkK8WIamiBI
Each cell has its own id(color, for example green is id=1) and flag isBorder(marked as white on pic if true). What I am trying to do is exclude set of cell with one state limited with borders(Grain) so i could work on each grain separately which means i would need to store all indexes for each grain.
Any one got an idea how to solve it?
Now that I've read your question again... The algorithm is essentially the same as filling the contiguous area with color. The most common way to do it is a BFS algorithm.
Simply start within some point you are sure lays inside the current area, then gradually move in every direction, selecting traversed fields and putting them into a vector.
// Edit: A bunch of other insights, made before I understood the question.
I can possibly imagine an algorithm working like this:
vector<2dCoord> result = data.filter(DataType::Green);
for (2dCoord in result) {
// do some operations on data[2dCoord]
}
The implementation of filter in a simple unoptimized way would be to scan the whole array and push_back matching fields to the vector.
If you shall need more complicated queries, lazily-evaluated proxy objects can work miracles:
data.filter(DataType::Green)
.filter_having_neighbours(DataType::Red)
.closest(/*first*/ 100, /*from*/ 2dCoord(x,y))
.apply([](DataField& field) {
// processing here
});
I have a CCSprite which gradually needs to be exhausted linearly from one end, lets say from left to right.For this purpose ,I am trying to change the textureRect property of the sprite so that the part that got exhausted from one end is 'outside' the displaying frame of the sprite.
I did this sort of thing before with a sprite that gets loaded from a spritesheet.And it worked perfectly.But I created this CCSprite using CCRenderTexture and by changing the textureRect property,the entire sprite gets disappeared.
The first image is the original CCSprite which I get from CCRenderTexture.The second image shows what I want to achieve.The black dotted rectangular portion of the Sprite needs to be omitted out.Only the blue dotted portion of the sprite needs to be displayed.Essentially,this blue dotted rectangle is my textureRect.
Is there any way how I could make my sprite reduce from one end.
Also is there any difference between a sprite created normally,and one created using CCRenderTexture.
I have done similar thing like this before using some low-level hack.
There is a work around solution if you use CCProgressTimer, that's very easy and I think it should be enough for your examples.
But you said in comment that you have some special requirements like "exhaust it from both the ends at once" then some low-level hack is needed. My solution from my last object is:
1) Get the texture image's raw data. In cocos2d you can use CCRenderTexture and in cocos2d-x you can use CCImage.
2) CCRenderTexture has a method of - (BOOL) saveToFile: (NSString *) name
format: (tCCImageFormat) format
. You can read its source code then try to save it into an 2D array instead like byte raw[1024][768]. Each element in this array represents one pixel on your picture(the type may not be byte, I'm not sure, nearly forget the details). The format MUST BE PNG since transparency will be needed.
3) Modify raw data directly, set pixel's transparency to 0x0 which you want it to disappear.
4) Re-initialize a CCRenderTexture using picture data you modified.
I can't provide the code directly since is a trade secret and core part of one of my projects. But I can share you my solution. You also need some knowledge about how PNG file works. Read:
https://en.wikipedia.org/wiki/Portable_Network_Graphics#File_header
Turns out I was making a silly mistake.While supplying values to the textureRect(CGRect),I was actually setting the textureRect.origin.y to the height of the texture which made my textureRect go beyond(above) the texture area.This explains why they were disappearing.