I am trying to make simple game with ball but how to make display to have frame around to avoid ball getting out of display ?
I want to have small hole in that frame so ball eventually can get out. I done this like putting couple rectangles ( with width or height 1px and other dimension is larger ) around display but when ball has large speed it pass through wall. Is there better solution for this.
Add physics body to the frame so that the ball will not pass through it
local topWall = display.newRect(0,0,display.contentWidth,2)
physics.addBody( topWall, "static", { friction = 0.5, bounce = 0 } )
Don't forget to start the physics engine "physics.start()" on the top of your code
P.S just modify the the topFrameand create another three walls on both side and on the bottom.
just make rect wider like 300px.
also you can try to set parameter ball.isBullet = true it will tell physics engine to keep eye on ball to avoid getting it through walls
Related
I have a sprite like this:
let sprite = SKSpriteNode(imageNamed: "sprite.png")
print("sprite height: \(sprite.size.height)") //results to 150
sprite.zRotation = 90 * degreesToRadians //turns sprite 90 Degrees
Results to this:
However:
print("sprite height: \(sprite.size.height)") //results to 150
Sprite height is still 150 even though it takes far less space height-wise.
Is there a way to get the actual height of a sprite after zrotating it? I know I could easily work around this with in the example above but my real problem is that I have various sprites at various zrotations and I'm trying to make sure that all of them are fully visible on screen.
So basically I have a sprite (red bar), an anchor point at 0,0 (blue dot) and visible screen (black frame).
I zrotate the sprites to random angles using arc4random_uniform but some sprites end up not being completely visible on screen. Basically I would have to know the height of the green arrow or assign it as the anchorPoint after zrotation. Or perhaps there are other ways that I have not thought of. All help appreciated!
0x141E's comment works.
sprite.frame.size.height
results to correct outcome.
I am building an endless runner game where platforms appear at random intervals and then scroll right to left across the screen.
I have a sprite that jumps up vertically using
- (void)makeCharacterJump {
[self.spriteCaveman.physicsBody applyImpulse:CGVectorMake(0.0f, 80.0f)];
}
The problem is that the effect of gravity on the sprite means that it falls quite quickly and cant make the gap between the platforms.
What I would like to do is slightly slow down the effect of gravity on the falling sprite so it creates the impression of slightly floating down.
Any ideas?
If the character is the only node affected by gravity then you can change the scene’s gravity with:
self.physicsWorld.gravity = CGVectorMake(0, desiredGravity);
If it is not then you’ll have to play with the character’s physics body properties: friction, linearDamping or angularDamping values.
Hope that helps.
I am developing a game with swift Sprite kit. But I've got a problem, as you can see in the picture I have a number of physical blocks with the same size aligned. When I slide this block above the others sometimes he gets stuck or do small jumps.
It seems that the physical bodies sometimes overlap.
Anyone know how I can fix it to have a continuous and without inprecision movement?
Some physics characteristics:
player.physicsBody?.friction = 0.0
player.physicsBody?.restitution = 0.00
player.physicsBody?.linearDamping = 0.1
player.physicsBody?.angularDamping = 0.0
player.physicsBody?.allowsRotation = false
player.physicsBody?.velocity.dx = 0
player.physicsBody?.velocity.dy = 0
player.physicsBody?.categoryBitMask = heroCategory
player.physicsBody?.contactTestBitMask = enemyCategory
player.physicsBody?.density = 2.3
The problem appears to be just a slight imperfection of physics engine (and hey, it's a simulation, and not completely accurate, I've run into this kind of thing before). I see that you are preventing rotation of the player, so you can change the physics body of the square player into a circle. This should be something like:
player.physicsBody = SKPhysicsBody(circleOfRadius: 10)
Replace 10 with the proper radius of your player. This should smooth out the bumps you are encountering.
How are you sliding the block?
I've had the same problem and I was able to solve it sliding my hero using SKAction to run a code block that changes the hero's velocity or by just simple running an SKAction.moveBy. Your SKAction should'nt be attempting to push your block against the ground. An action to move the block only in the x direction.
You can also smooth the surface by making sure your physicsBody(s) of ground blocks are not overlapping. Introduce a gap of 1-2 points. Or maybe group tiles with a single physicsBody. This may help as well.
I am creating a tilemap platform game in SpriteKit. I assigned collision paths to the physics body of all ground tiles and made them non-dynamic. To the player I assigned two collision polygons: a circle on the bottom and a rectangle on the top.
The player sprite has a fixed position on screen, while the level is scrolling from right to left. Now, as long as the player sprite is on flat ground, the collisions work perfectly and the player is walking on the ground. However, I also have some sloped terrain tiles that I want the player to follow (e.g. walking uphill). But when the player reaches a sloped tile, he simply bounces off of it, being unable to "climb" it.
Similarly, when I drop the player from above on a sloped tile, he slides down the "hill", instead of remaining in position.
I have both restitution and friction set to 0.
So how can I make the player sprite follow the ground regardless of its shape and how can I make the player stay on a sloped tile instead of sliding down?
I tried using SKConstraints with positionX set to a constant value. At first it seemed to work, but then the player got stuck in the middle of a sloped tile and eventually fell through it.
I also tried different shapes of collision polygons on the player (e.g. a rectangle instead of a circle at the bottom) but that changed nothing.
Any help is appreciated!
This has more to do with your game logic instead of your map properties. You need to have several "states" for your player. For example, if your player is idle you can set the CGVector to 0,0. This will stop the player from moving in any direction.
To give you some examples on movement. Let's say you want to make your object move right:
// move node's physics body to the right while leaving vertical movement as is
// 160 is just an example
myNode.physicsBody.velocity = CGVectorMake(160, self.physicsBody.velocity.dy);
// do not allow right movement to exceed 160
if(myNode.physicsBody.velocity.dx > 160)
myNode.physicsBody.velocity = CGVectorMake(160, self.physicsBody.velocity.dy);
To move left you inverse the dx value:
myNode.physicsBody.velocity = CGVectorMake(-160, self.physicsBody.velocity.dy);
if(myNode.physicsBody.velocity.dx < -160)
myNode.physicsBody.velocity = CGVectorMake(-160, self.physicsBody.velocity.dy);
Allow myNode to be affected by gravity and it should remain in contact with the ground as it moves down a slope.
It's a tilemap platform game...
Then gravity isn't important, put gravity to a very low value and then change all your impulses for the jumps and such in relation to the change in gravity...
OR,
Possibly, if the game isn't randomly generated you can set up a uibezierpath, and turn the path off if he stops moving up the hill.
But then if he stopped mid-hill or was starting from the top, he would still slide down...
And increasing friction (not setting it to 0) may help. Try friction at 1?
This seems to be a major oversight by Apple, but since SKPhysicsJoints have their anchor points set in Scene coordinates, this makes doing any kind of scrolling game impossible.
To simulate a camera in SpriteKit you create a WorldNode which contains all of the gameplay elements, and then pan that around the scene. Unfortunately, doing this causes the Scene coordinates of every object in the game to change on every frame as you pan the world around. In turn, this breaks the joint anchor points, and things go berserk.
There isn't even a way to change the joint's anchor point, so I don't even have a way of just updating the coordinate every frame. It would seem that using SKPhysicsJoint in a scrolling game is not an option.
Does anyone know of a way around this?
Ok, I think I figured out what was going on, and I was totally incorrect in my original assumption. The reason my anchor points looked incorrect is because the [convertPoint toNode] call was returning me Scene coordinates that were incorrect. After several hours I realized it was off by exactly half the screen dimensions. My Scene has an anchorPoint of (0.5, 0.5), but this screws up the conversion values. So, if I simply offset the point by width/2, height/2 it's correct:
GPoint pt = CGPointMake(anchorWorldX, anchorWorldY);
pt = [gGameScene convertPoint:pt fromNode:gGameWorld]; // convert to scene coords, but it's WRONG
pt.x += scene.size.width * scene.anchorPoint.x; // this properly adjusts the value to be correct
pt.y += scene.size.height * scene.anchorPoint.y;
SKPhysicsJointPin* pin =[SKPhysicsJointPin jointWithBodyA:hinge.physicsBody bodyB:door.physicsBody anchor:pt];