Hi guys I Am developing the application in cocoas2d using the box 2d frame work but unfortunately
i'm not able to restrict the gray ball in the half screen area of the image shown here
i want that ball not to go opposite part of the screen
I Have Used The b2Mousejoint For to move the ball around the screen
b2PrismaticJointDef restrict on any particular axis
But
i want to restrict on the particular rect area of the screen
You could create your custom distance joint which will restrict global axes of the ball. But it will be hard if you never write your own physics engine.
There are 2 easier ways to implement what you want.
Create 4 static "border" boxes around the area where the ball must stay. Then place the ball and the boxes into one collision group.
However, the response of the "border" boxes will not be instant. Therefore, the ball at high speed will sometimes "sink" into the boxes, then be popped out.
You can correct the position and reset the speed of the ball manually in code when it crosses the bounds of the desired area. But it may lead to the unstable physics simulation.
Related
I'm making a game where I move a red cube across a plane with arrow keys (I am setting the velocity in order to get a constant speed) Here is a preview:
game
Currently, I am just using a plane with a grid material/texture. However, I wanted to change one of the tiles in this grid to a different color and detect when my cube passes over it.
My idea was to simply replace the plane with a bunch of quads. However, when I do that and try to navigate my cube across the quads, it seems to collide with the side of the quad and flip up, despite the fact that they are all at the same height and positioned right next to each other.
Is there a way to make the quads flush so when I push my cube over it, it won't collide with the side of the quads? Is there a better way to create this behavior?
You can disable colliders at this quads and add invisible big plane with collider
Currently i am making Dice(Dice is a rigid body, has box collider) rolling. I have 6 dice in the box(the box is actually made up of plane and wall which is cube, it has a box collider). User can roll the dice by clicking the button, each of the dice is applied with the random force in random direction.
Now after sometimes the dice rests, but instead of resting horizontally on the plane some times the die rests in the unexpected position such as inclined with walls and even sometimes inclined within itself.
What i am doing currently?
I have checked if the die is sleeping and if it is sleeping and not parallel with horizontal, i am changing the transformation value. But the problem is it is slow and takes much time.
I want to rest them in the plane horizontally in a better and fast way.
Have you tried setting up your Drag and Mass on your rigid body :)
I am searching for a solution to how to make a perfect pinch zoom in Unity by moving the camera along the forward:
Set up:
Horizontal plane centred at the origin with all Game objects.
Perspective camera with FOV 10, offset at (10,10,10) looking down at a 45 degrees angle, so that it looks at the origin (there is also a rotation of 45 degrees around the axis pointing up, to achieve this).
What I need:
When I place two fingers on the screen I am touching two GameObjects with them - so the screen coordinates under the fingers correspond to certain world coordinates. When I make a pinch movement (with moving two fingers or only one) I want the new screen coordinates to correspond to the same world coordinates that were under the fingers at the beginning of the whole interaction.
So to simplify even further - whenever I touch the screen with two fingers, I want the world coordinates corresponding to the screen coordinates under my fingers to always stay under the fingers (allowing a very small margin of error).
An example of this perfect zoom for which I am looking for you can see in the mobile game Boom Beach from Supercell.
I already tried to move the camera along its forward vector and to reposition it and I get pretty good results, but pretty much always the GameObjects underneath ‘slip’ away from under my fingers, that is at some points are no longer underneath them. It would be great if there was a mathematical solution to this, but if it’s necessary to compute the answer (through some search for example) then this is totally fine.
If the setup/scenario is not clear, I could provide some sketches to clarify it a bit more.
Hope someone can help me! :)
I would set up a system that detects when the user is zooming in and out if you are using GameObjects to pinpoint where the fingers are that is easy to do with Vector3.distance. After that, I would make a function that moves the camera closer to your desired zoom level with Vector3.MoveTowards(camera position, desired position, the speed of movement) where I would set "speed of movement" as a mathf.sqrt(vector3.distance(Camera position, Desired position));
as for the "desired position" I would set that Vector3(position) as a fraction of a line between two game objects that represent your maximum and minimum zoom level.
EDIT: with that, you should have a very nice camera system
I am working on a tabletop game that user controls using accelerometer in the phone. It is pretty similar to Labyrinth on iOS.
The scene contains a tabletop created using planes and cubes, and a sphere as a ball. As it works in Labyrinth game, on tilting phone ball should drop to the tilted side, while the camera stays centered to table. I am trying to do similar thing where user tilts the phone, and objects on table move to tilted side.
Currently, I add the x and z component to Physics.gravity on tilt. Sadly, this change in gravity does not affect the ball which stays put on the table. Use gravity is selected for the ball, and it drop down from height to the tabletop initially and then comes to halt. After the initial drop, ball does not react to any gravity change.
I have also tried rotating the whole table, but using transform.rotate does not work either. The table rotates perfectly, alongwith the camera, but the ball stays put hanging in the air. So, currently I am out of my depth about the issue.
Is there any other way to allow tilt action registered, so that ball moves to the tilted direction? I cannot use addforce function, as there are multiple objects which need to react to tilt, and it will be difficult to keep track of that many addforce calls. How else can I get it working?
See this post for some related information.
As for why your sphere is sticking to the table, can I assume your sphere has a rigidbody? If so, you need need to wake it up:
if (rigidbody.IsSleeping())rigidbody.WakeUp();
Ideally you would make that call only after detecting a change in orientation/gravity, not every frame.
I am working on a game which has working similar to game monkey kick off. I have one ball bouncing on a place at the left side of screen and depending upon the position of the ball I apply linearImpulse to the ball on user touch so that it appears that the ball is kicked.
But what happens is when i apply impulse the ball goes out of the screen bounds. I dont want the ball to go out of the horizontal screen bounds whereas it can go out of the screen vertically.I tried using CCFollow but it doesn't give the realistic feel to the game flow.
I tried THIS tutorial, but dint help much.I managed to scroll the background,Only this part remains.
Any Ideas on how the ball should not move out of the horizontal screen boundary..? but in case of vertical boundary on the other hand it can go out of the bounds.
If you're not using physics, it's a simple bounds check. Assuming the screen width is 320 points this will keep the ball inside the screen horizontally:
CGPoint ballPos = ball.position;
ball.position.x = fmaxf(0, fminf(320, ballPos.x));
ball.position = ballPos;
UPDATE: I noticed you mentioned linear impulse. So you're using a physics engine. In that case, create a horizontal wall on both sides. See the cocos2d Box2D or Chipmunk templates how to enclose the screen with a collision border, then use only the left and right side borders in your game.