desmosLogger

Do you like debugging your physics engin with desmos? Generates copy pastable code for desmos. A focus of the package is to make the generated desmos graphs interactable througth variables.

Installation

npm install desmoslogger

dependencys -earcut for polygon triangulation.

Demo

let mVects = [[1.304,-1.493,4.132],{x:0.7061,y:0.1408,z:6.363},
"(0.1883,-2.309,4.431)","(0.4871,-3.126,3.316)",
"(2.962,-3.126,0.8404)","(3.833,-0.6766,2.419)",
"(2.12,0.1404,4.949)","(2.36,-1.183,-0.7697)",
"(0.7599,-1.699,0.3134)","(2.687,0.3665,0.452)"];

let e2Faces = [[0,1,2,3,4,5,6],[7,5,6],[7,9,6],[7,8,3],[7,4,3],[7,8,9],[9,8,6],[8,6,0],[8,1,0],[8,1,2],[8,3,2],[7,4,5]];

const path = require("path");
const { createDesDebug } = require("desmosLogger");

const TMP_LOG = path.join(__dirname,"model_desmoslog.txt");

let MdlDes = createDesDebug(TMP_LOG);
MdlDes.model(mVects,e2Faces);

By default all expressions are written to desmoslog.txt in the project root. Open that file and paste its contents into Desmos.

Point format

All points provided can be one of 3 types below,

• [1,2,3]
• "(1,2,3)" or "1,2,3"
• {x:1,y:2,z:3}

Naming conventions

Varibale names in desmos are made up of the varibale letter and subscripts. For each elemnt of the graph the below naming convention is used.

• objectLetterobjectCount elemntSpesification elementCount

desmos

• A focus of the package is to make graphs a interactive as possibal.
• Some values need to be defined but not visibal this is achived by defining points as a output of functions. f(a)={(p.x,p.y,p.z)} get point with f(1)

Public API

All methods return a Promise that resolves when their log writes have been enqueued.

• init(): Promise<void>
  Clears the log file and resets all internal counters for points/lines/triangles/etc.

• point(point): Promise<void>
  Logs a point Pn in Desmos.

• line(point1 [,point2,options]): Promise<void>
  Logs a line segment Ln between two points. If no point2 is provided the line segment will be between point1 and the oigin

  options

  • showPoints: if true create variables for each point, if false directly inserts value into segemnt.

• triangle(p1, p2, p3[,options]): Promise<void>
  Logs a triangle Tn with vertexes p1,p2,p3 , optionally logging its three vertices as named points.

  options

  • showPoints: if true create variables for each point, if false directly inserts value into segemnt.

• vector(direction[,origin,options]): Promise<void>
  Logs a vector Vn starting from origin in the given direction.

  options

  • len:length of vector

  desmos

  • creates variables origin, to refrence.

• normal(origin, point1, point2[, options]): Promise<void>
  Logs a normal vector Nn derived from the oriented triangle (origin, p1, p2), scaled to length. Point1, and point2 should be in order of the right rule from the origin.

  options

  • showTriangle:if true displays triangle between origin, point1, point2
  • len:length of normal

• poly(points[,options]): Promise<void>
  Logs a polygon surface Sn defined by a list of 3D points.

  • points:Array of points making up the polygon. Order must form a path around the edge.

  options

  • justShow:if true do not display basis vectors or tagvectors.
  • tagVects:vector will be added to the center of mass of polygon, to show rays,normals etc.
  • offSet:defines the origin point of the model

  desmos

  • points projected on plane and basis found, change of basis to convert all points to 2d cordinates, define change of cordinate function f(x,y)=unit2*x + unit3*y + dot(unt1*p1)*unit1 + offSet. List vertexes in 2d cordinate space v = [p1,p2,...]. Use earcut algorithum, define triangle constructor function f(a,b,c)=triangle(v[a],v[b],v[c]). Define all triangles.
  • UI:offset origin point of polygon
  • UI:``

• function model(points, faces [,options]): Promise<void>
  Logs a simple model composed of multiple polygon faces.

  • points: array of vertex positions (as strings/arrays/objects)
  • faces: array of faces, where each face is an array of indices into points

  options

  • justShow:if true do not display basis vectors or tagvectors.
  • tagVects:Array of vectors to be added to each face of the model.
  • offSet:defines the origin point of the modelz