I'm following the tutorial here to mimic Flappy Bird. At the part to scroll the game scene:
- (void)update:(CCTime)delta {
_hero.position = ccp(_hero.position.x + delta * scrollSpeed, _hero.position.y);
_physicsNode.position = ccp(_physicsNode.position.x - (scrollSpeed *delta), _physicsNode.position.y);
...
}
Ideally the whole world will scroll left, and _hero (which is a child node of _physicsNode) move right with the same speed it would stay still on the screen. But when I run the code on simulator the _hero sprite just blast off to the right at the speed of light (about 10~20 times faster than the scrolling speed of _physicsNode). The _physicsNode and every other things inside it is scrolling left at normal speed as intended.
If I don't give _hero any movement it would scroll along with _physicsNode normally.
I have tried other method like using CCAction at game start:
CCAction *moveAction = [CCActionMoveBy actionWithDuration:1 position:ccp(-scrollSpeed,0)];
CCActionRepeatForever *repeatAction = [CCActionRepeatForever actionWithAction:(CCActionInterval *)moveAction];
[_physicsNode runAction:repeatAction];
And still get the same result. The speed value that _hero receive is always different from the speed that _physicsNode receive.
Could anyone explain to me why this is happening and how to fix it?
I'm using cocos2d 3.3 if it helps.
I finally figured it out.
The _hero node had its positionType set to CCPositionTypeNormalized (because I was trying to center him on the screen) while the _physicNode has its positionType as CCPositionTypePoints. Any change to the node's position (including movement actions) are based on the node's positionType. The result is that when I move the _hero node by 2, it doesn't move 2 points but 2% of the parent node's width instead.
I fixed it by aligning the _hero on SpriteKit using CCPositionTypeNormalized, then switching it to CCPositionTypePoints at game start.
Related
I'm doing a platformer game using cocos2d-x v3 in c++, where the maps are usually very large, the visible screen follows the object through the map.
Let's say I want to show a sprite in the top right corner of the screen and it would be in this position even when the screen is following the object.
Using the object position doesn't do it.
Is there a way to show a sprite or whatever in the screen and it would be in the screen even when the screen is moving?
Ps. I'm super noob in game development
As it's written here, you whould use convertToWorldSpace
convertToWorldSpace converts on-node coords to SCREEN coordinates.convertToWorldSpace will always return SCREEN position of our sprite, might be very useful if you want to capture taps on your sprite but need to move/scale your layer.
Generally, the parent node call this method with the child node position, return the world’s postion of child’s as a result. It seems make no sense calling this method if the caller isn’t the parent…
So, as you can read,
Point point = node1->convertToWorldSpace(node2->getPosition());
the above code will convert the node2‘s coordinates to the coordinates on the screen.
For example if the anchor position of node1 is which will be the bottom left corner of the node1, but not necessarily on the screen. This will convert the position of the node2 which is to the screen coordinate of the point relative to node1 ).
Or if you wish, you can get position relative to scenes' anchor points with function convertToWorldSpaceAR.
So there are some assumptions that will have to be made to answer this question. I am assuming that you are using a Follow action on your layer that contains your map. Check here for example. Something like:
// If your playerNode is the node you want to follow, pass it to the create function.
auto cameraFollowAction = Follow:create(playerNode);
// running the action on the layer that has the game/map on it
mapLayer->runAction(cameraFollowAction);
The code above will cause the viewport to "move" to where the player is in world position. So following the player on your map that's bigger than the current viewport. What I did for my in-game menu/hud is add the Hud onto a different layer and add it to the root of the main game scene. The scene that does not have the follow action running on it. Something like below.
// Hud inherits from layer and has all the elements you need on it.
auto inGameHud = HudLayer::create();
// Add the map/game layer to the root of main game scene
this->addChild(mapLayer, 0);
// Add the hud to the root layer
this->addChild(inGameHud, 1);
The code above assumes 'this' to be your MainGameScene. This restricts the Follow action from scrolling the element off the screen. Your element will be on the screen no matter where in World space your scene currently is.
Let me know if this is clear enough. I can help you out more if you get stuck.
I've managed to do it using a Parallax Node, and using the velocity which the sprite goes to Vec2(0,0), this way it stays always on the same spot in the screen.
You can always just put that sprite into different node / layer that everything else is. That way moving this layer / node won't move the sprite
I'm working on a game project in c++ using programming oriented object and classes but I can't figure out a way to animate the following graphics.
What I need is while the player is holding left key or the right key, the graphics should be appearing to make the character like moving and when they stop holding the key it'll turn to idle graphic.
I can't paste the whole source code here, i have many classes, and functions.. All I need is a BASIC idea of how to implement it, an example or a function anything useful. I don't need libraries because i just have two sprites to animate so it's not necessary.
As an example be Sprites the class that creates the object and Koala the one that moves it and prints it in a certain position.
Sprites idleSprite, walkingSprite;
Koala koala;
These declarations are just for avoiding other explanations.
I would appreciate your help.
PD: Don't worry about the keyboard keys, or other classes all I need is how to animate a sprite.
Koala should have two states:
a direction state: enum Direction {Left,Right};
a movement state. enum Movement { Idle, Walk };
As you have only one picture for the walking status, moving graphically the picture around will give the impression of a floating body. I'd recomment that you'd really have at least two walking positions to show that the foots are moving:
a movement step counter
a constant for the maximum number of steps.
Then the states should be updated in your game loop according to keyboard status and elapsed time. The pseudo code would be something like:
if (!arrow_key_pressed()) {
status_movement = Idle;
lasttimer = gametimer(); // keep track of last event
}
else {
status_movement = Walk;
if (left_arrow_pressed() )
status_direction = Left;
else if (right_arrow_pressed() )
status_direction = Right;
if (gametimer() - lasttimer > 2 ms ) { // if enough time,
if (status_direction==Left)
position_x -= step_increment;
else if (status_direction==Right)
position_x += step_increment;
movement_step = (movement_step+1) % maxi_steps;
lasttimer = gametimer();
}
}
All you have then to do is to restore te background of the picture at tis old position, and draw the picture at the position. For this, youd could call a function with paramters position_x, direction, movement status and status step, to return/draw the sprite at the right place.
Cocos2d offers two ways to let the player jump up, but by using jumpto() and jumpby(), people could not change the position of the sprite any more when it is jumping up.
How to write a method so that the sprite can jump like the "Super Mario"?
Some time ago I contributed some cocos2d code which made CCMove and CCJump actions stackable. See here. Starting from cocos2d 2.1, you can apply a CCJump actions concurrently with other movements.
However, if you want to deeply fine tune how the controls of your game feel, I'd avoid using CCActions altogether and I'd manage the sprite.position directly by processing player input.
you have to check for two condition for making your player to jump, same as in Super Mario.
Condition 1)
Only jump button is pressed at that time in CCJumpTo action you have to give the next position as the current position , height and no. jumps as one.
id jump = [CCJumpTo actionWithDuration:1 position:ccp(player.position.x, player.position.y)) height:20 jumps:1];
Condition 2)
When jump and forward button is pressed at that time in CCJumpTo action you have to give the next position as the current position.x + the distance you want to cover by jump,this will be static all the time , height and no. jumps as one.
id jump = [CCJumpTo actionWithDuration:1 position:ccp(player.position.x+20, player.position.y)) height:20 jumps:1];
And at the end you have to run jump action on player, hope you found this as solution for your question...!!
I'm using a particles, slightly modified CCParticleFlower with positionVar to be in form of vertical line, from top to bottom. In CCNode update I constantly change the position of the particles from left to right across the whole screen, when it reaches the right side I set x to 0 and start scrolling to the right.
The problem is when I reset the X value to 0, all particles blinks, they disappear for about one frame and appear in the next frame, it causes a nasty flickering effect.
It does not happen when I increment X values by small numbers but when the particle position is reset to its beginning position it flickers, on win32, android and ios. I’m using most recent 1.1 version (master branch)
I recently had something of a similar problem where the particles would jump around whenever their parent changed direction. I'm not sure if it's exactly the same problem, but here's the thread I found that helped with my problem:
http://www.cocos2d-iphone.org/forum/topic/17167
The relevant post:
I just encountered the same problem and it took me a while to get to the bottom of it, >here's the low down: do not use
[self schedule:#selector(NextFrame:)];
Instead, use
[self scheduleUpdate];
and rename NextFrame: to update:
Using a custom selector schedules your update at the very end of the CCScheduler queue, in other words, it will cause your NextFrame: method to be called AFTER the particle system's update: method, because the particle system schedules its own update method with a priority of 1.
This is not good because the position of the quads for the particles are updated using the current position of the emitter, and then the emitter is moved in your NextFrame: method, which causes all the particles to be moved again because the position of the emitter is really the position of the CCNode that draws the particles.
By using scheduleUpdate, you really schedule your update: method with a priority of 0, which means it will be called before the particle system's update: method and all will be well.
So basically, add an update method to your class and call scheduleUpdate instead of manually scheduling it.
I want to set the contentsize of scrollayer.
I have a scrollayer, it's CCLayer type and moving is set by ccTouchMove. I have one schedule for smoothing. BUT.
Problem is that scrolling layer is big like the whole display. I want to set the contentsize of scrollayer. Content in this layer will be scroll and showing ONLY in this layer. Not taking up the whole display. Something like this
Scrolling just in gray CCLayer (scrollayer) ....NOT WHOLE SCREEN.
Can you help me?
P.S.: Setting CCLayerColor and initWithColor:Width:Height: is not working. It just makes some stupid color box and it's moving too.
ok, honestly i would put the window frame at a higher z than the scrolling object ... if you dont you may have to crop and change sprite on the fly for the window content, nasty (at least that is the one way i could do this, without further research).
so :
// initialize this logic somewhere useful
CCNode scrollableContent;
CCSprite windowFrame;
BOOL isScrollPossible;
[self addChild:scrollableContent z:0];
[self addChild:windowFrame z:1];
// and in the touch delegate methods
-(void) ccTouchBegan:{
check if the touch happened in the window, if yes, scrolling is possible
}
-(void) ccTouchMoved:{
if (isScrollPossible) {
compute displacement
compute nextPosition for scrollableContent node;
if ( nextPosition in window ) {
// make scrollableContent follow touch
scrollableContent.position=nextPosition;
} else {
// stop any further scrolling until the next 'touch began'
isScrollPossible=NO;
}
} else {
// scroll not possible, do nothing
}
}
This is the basic idea. You may need clamping logic to prevent the creeping of scrollableContent beyond the edges of the window.
Edited for typos.
After trying desperately with masking and GL_SCISSOR, I settled on cutting a hole in the foreground and only moving the background object when onTouchMoved updated.
To see it in action, have a look at the Stats page of Angry Gran.