Using Cytoscape.js, how can I constrain movement of a node to a single (i.e. either the x or y) axis? I'd like to be able to make it so a node can only be dragged vertically or horizontally, but not both. In other words, I'd like to lock a node, but only on a single axis. I'm not sure if this is possible, and wasn't able to find anything in the documentation that mentioned this specifically, so I figured I'd ask.
Thanks in advance!
Use the automove extension, which lets you set whatever restrictions on node positioning that you like. Constraining the x value is as easy as passing a (x, y) => { return { xConst, y }; } function to the extension.
I ended up coming up with a way to approximate the result that I wanted by listening for each node's free event, and setting its position to what I needed it to be. This doesn't restrict dragging of nodes to a single axis, but it does restrict dropping of nodes to a single axis, if that makes sense.
Here is the Cytoscape.js description of the free event:
free : when an element is freed (i.e. let go from being grabbed)
from: http://js.cytoscape.org/#events/collection-events
Related
in this video, https://youtu.be/klBvssJE5Qg I shows you how to spawn enemies outside of a fixed camera. (this is in GDscript by the way) How could I make this work with a moving camera? I wanna make a zombie fighting game with a moving camera and zombies spawning outside that.
I would really appreciate help with this.
I've tried researching on the internet about how to do it, but I just didn't find it.
N/A..................................
After looking at the video, I see they are using this line to spawn:
Global.instance_node(enemy_1, enemy_position, self)
This suggest to me a couple thing:
The position is probably either relative to the self passed as argument or global.
There must be an Autoload called Global that I need to check to make sure.
And the answer is in another castle video.
In the video Godot Wave Shooter Tutorial #2 - Player Shooting we find this code:
extends Node
func instance_node(node, location, parent):
var node_isntance = node.instance()
parent.add_child(node_instance)
node_instance.global_position = location
return node_instance
And thus, we are working with global coordinates global_position. Thus enemy_position is used as global coordinates.
Ok, instead of using enemy_position as global coordinates we are going to use it as local coordinates of the Camera2D (or a child of it). Which means you need a reference to the Camera2D (which I don't know where do you have it).
You could make your code in a child of the Camera2D, or take the transform of the Camera2D using a RemoteTransform2D. Either way, you could then work in its local coordinates. Thus you would do this:
Global.instance_node(enemy_1, to_global(enemy_position), self)
Or you could have a reference by exporting a NodePath (or in the newest Godot you can export a Camera2D) from your script and set it via the inspector. So you can do this:
Global.instance_node(enemy_1, camera.to_global(enemy_position), self)
Where camera is your reference to the Camera2D.
In the following section of Arena.gd:
func _on_Enemy_spawn_timer_timeout():
var enemy_position = Vector2(rand_range(-160, 670), rand_range(-90, 390))
I believe you can add the X and Y coordinates of the camera to their corresponding random ranges in the enemy position Vector2. This will displace the enemy depending on where the camera is currently located.
You can get the position of the camera with this:
get_parent().get_node("Name of your camera").position
When this is all put together:
func _on_Enemy_spawn_timer_timeout():
var enemy_position = Vector2(rand_range(-160, 670) + get_parent().get_node("Name of your camera").position.x, rand_range(-90, 390) + get_parent().get_node("Name of your camera").position.y)
Keep in mind that you might need to displace the values in the following while loop as well. I hope this helps.
So basically im doing this for my minecraft spigot plugin (java). I know there are already some land claim plugins but i would like to make my own.
For this claim plugin i'd like to know how to get if a point (minecraft block) is inside a region (rectangle). i know how to check if a point is inside a rectangle, the main problem is how to check as quickly as possible when there are like lets say 10.000 rectangles.
What would be the most efficient way to check 10.000 or even 100.000 without having to manually loop through all of them and check every single rectangle?
Is there a way to add a logical test when the rectangles get generated in a way that checks if they hold that point? In that case you could set a boolean to true if they contain that point when generated, and then when checking for that minecraft block the region (rectangle) replies with true or false.
This way you run the loops or checks when generating the rectangles, but when running the game the replies should happen very fast, just check if true or false for bool ContainsPoint.
If your rectangles are uniformly placed neighbors of each other in a big rectangle, then finding which rectangle contains point is easy:
width = (maxX-minX)/num_rectangles_x;
height = same but for y
idx = floor( (x - minX)/width );
idy = floor( (y - minY)/height );
id_square = idx + idy*num_rectangles_x;
If your rectangles are randomly placed, then you should use a spatial acceleration structure like octree. Then check if point is in root, then check if point is in one of its nodes, repeat until you find a leaf that includes the point. 10000 tests per 10milliseconds should be reachable on cpu. 1 million tests per 10ms should be ok for a gpu. But you may need to implement a sparse version of the octree and a space filling curve order for leaf nodes to have better caching, to reach those performance levels.
I render a graph using visjs. The shape of the nodes are of type dot. Each node is given a custom size using the size attribute.
When the graph is rendered some of the nodes overlap. So the graph looks like in the following picture:
I expected a graph like the this picture is showing:
What am I doing wrong?
Try to use the physics configuration.
see this example of visjs.
GOOD LUCK.
To be more specific compared to the TERMIN's answer, in the physics configuration example you can see (at least for the barnesHut solver) that increasing avoidOverlap prevents overlapping even when springConstant is equal to zero and
var options = {
"physics": {
"barnesHut": {
"avoidOverlap": 0.2
}
}
}
is probably enough (but you may increase the value according to your needs).
I have several boxes (x,y,width,height) randomly scattered around, and some of them need to be linked from point (x1,y1) in box1 to point (x2,y2) in box2 by drawing a line. I am trying to figure a way to make such line avoid passing through any other boxes (other than box1 and box2) by drawing several straight interconnected lines to go around any box in the way (if it is not possible to go with one straight line). The problem is that I don't know an algorithm for such thing (let alone having a technical/common name for it). Would appreciate any help in the form of algorithm or expressed ideas.
Thanks
Assuming that the lines can't be diagonal, here's one simple way. It's based on BFS and will also find the shortest line connecting the points:
Just create a graph, containing one vertex for each point (x, y) and for each point the edges:
((x,y),(x+1,y)) ((x,y),(x-1,y)) ((x,y),(x,y+1)) ((x,y),(x,y-1))
But each of this edges must be present only if it doesn't overlap a box.
Now just do a plain BFS from point (x1,y1) to (x2,y2)
It's really easy to obtain also diagonal lines the same way but you will need 8 edges for each vertex, that are, in addition to the previouses 4:
((x,y),(x-1,y+1)) ((x,y),(x-1,y-1)) ((x,y),(x+1,y-1)) ((x,y),(x+1,y+1))
Still, each edge must be present only if it doesn't overlap a box.
EDIT
If you can't consider space divided into a grid, here's another possibility, it won't give you the very shortest path, though.
Create a graph, in which each box is a vertex and has an edge to any other box that can be reached without the line to overlap a third box. Now find the shortet path using dijkstra between box1 and box2 containing the two points.
Now consider each box to have a small countour that doesn't overlap any other box. This way you can link the entering and the exiting point of each box in the path found through dijistra, passing through the countour.
Put all (x,y) coords of the corners of the boxes in a set V
Add the start- and end coordinates to V.
Create a set of edges E connecting each corner that does not cross any box-side (except for the diagonals in the boxes).
How to check if a line crosses a box side can be done with this algorithm
Now use a path-finding algorithm of your choice, to find a path in the graph (V, E).
If you need a simple algorithm that finds the shortest path, just go with a BFS.
(This will produce a path that goes along the sides of some boxes. If this is undesirable, you could in step 1 put the points at some distance delta from the actual corners.)
If the edges may not be diagonal:
Create a large grid of lines that goes between the boxes.
Throw away the grid-edges that cross a box-side.
Find a path in the grid using a path-finding algorithm of your choice.
I have a projectile that I would like to pass through specific coordinates at the apex of its path. I have been using a superb equation that giogadi outlined here, by plugging in the velocity values it produces into chipmunk's cpBodyApplyImpulse function.
The equation has one drawback that I haven't been able to figure out. It only works when the coordinates that I want to hit have a y value higher than the cannon (where my projectile starts). This means that I can't shoot at a downward angle.
Can anybody help me find a suitable equation that works no matter where the target is in relation to the cannon?
As pointed out above, there isn't any way to make the apex be lower than the height of the cannon (without making gravity work backwards). However, it is possible to make the projectile pass through a point below the cannon; the equations are all here. The equation you need to solve is:
angle = arctan((v^2 [+-]sqrt(v^4 - g*(x^2+2*y*v^2)))/g*x)
where you choose a velocity and plug in the x and y positions of the target - assuming the cannon is at (0,0). The [+-] thing means that you can choose either root. If the argument to the square root function is negative (an imaginary root) you need a larger velocity. So, if you are "in range" you have two possible angles for any particular velocity (other than in the maximum range 45 degree case where the two roots should give the same answer).
I suspect one trajectory will tend to 'look' much more sensible than the other, but that's something to play around with once you have something working. You may want to stick with the apex grazing code for the cases where the target is above the cannon.