javascript - D3js find closest point on circle -

-

what i'm trying achieve take current coordinates of mousemove event , match them coordinates of closest location on circle. i've managed partially working using loop iterates on each possible point in circle , compares coordinates in order find closest point: 

        (var = math.pi; > -math.pi; -= 0.01) {              // coords of current point in circle:              var curx = math.sin(i+math.pi / 2)*radius + 200,             cury = math.sin(i)*radius + 200;              // conditional attempts find coords of point closest cursor...                  if (math.abs((x - curx)) < distancex && math.abs((y - cury)) < distancey ) {                     distancex = math.abs((x - curx));                     distancey = math.abs((y - cury));                      // , assigns values newx/newy variables                      newx = curx;                     newy = cury;                 }              }

the trouble solution return wrong coordinates , i'm not sure why.

jsfiddle see mean:

https://jsfiddle.net/eln4jsue/

no need loop, compute point between center of circle , mouse on circle.

var dx = x - 200,     dy = y - 200,     dist = math.sqrt(dx*dx + dy*dy),     newx = 200 + dx * radius / dist,     newy = 200 + dy * radius / dist;

https://jsfiddle.net/3n0dv5v8/1/


Comments

Post a Comment

Popular posts from this blog

Java 3D LWJGL collision -

-
i making 3d java game lwjgl library, , wondering how add collision detection, player not go through models. i using obj models. here objloader class, loads models: package renderengine; import java.io.bufferedreader; import java.io.file; import java.io.filenotfoundexception; import java.io.filereader; import java.util.arraylist; import java.util.list; import models.rawmodel; import org.lwjgl.util.vector.vector2f; import org.lwjgl.util.vector.vector3f; public class objloader { public static rawmodel loadobjmodel(string filename, loader loader){ filereader fr = null; try { fr = new filereader(new file("res/"+filename+".obj")); } catch (filenotfoundexception e) { system.err.println("couldn't load file!"); e.printstacktrace(); } bufferedreader reader = new bufferedreader(fr); string line; list<vector3f> vertices = new arraylist<vector3f...
Read more

spring - SubProtocolWebSocketHandler - No handlers -

-
i have ugly error during deploying spring app on jboss. 18:11:16,025 error [org.apache.catalina.core.containerbase.[jboss.web].[default-host].[/consumer]] (msc service thread 1-7) exception sending context initialized event listener instance of class org.springframework.web.context.contextloaderlistener: org.springframework.context.applicationcontextexception: failed start bean 'subprotocolwebsockethandler'; nested exception java.lang.illegalargumentexception: no handlers @ org.springframework.context.support.defaultlifecycleprocessor.dostart(defaultlifecycleprocessor.java:176) [spring-context-4.1.3.release.jar:4.1.3.release] @ org.springframework.context.support.defaultlifecycleprocessor.access$200(defaultlifecycleprocessor.java:51) [spring-context-4.1.3.release.jar:4.1.3.release] @ org.springframework.context.support.defaultlifecycleprocessor$lifecyclegroup.start(defaultlifecycleprocessor.java:346) [spring-context-4.1.3.release.jar:4.1.3.release] @ org.s...
Read more

methods - python can't use function in submodule -

-
my folder structure this: pythonstuff/ program.py modulea/ __init__.py foo.py bar.py here's code bar.py : def hello(): print("hello, world!") here's code program.py : #!/usr/bin/env python3 modulea import bar bar.hello() i run $ python3 program.py somehow error: file "program.py", line 3, in <module> bar.hello() attributeerror: 'module' object has no attribute 'hello' edit: __init__.py file empty. edit2: after trying realized had bar.py in root directory contained hello() method. bar.py in modulea/ directory empty. add it import os __all__ = [] module in os.listdir(os.path.dirname(__file__)): if module != '__init__.py' , module[-3:] == '.py': __all__.append(module[:-3]) the init .py files required make python treat directories containing packages; done prevent directories common name, such string, unintentionally hiding v...
Read more