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OBJReader

Introduction

The vtkOBJReader aims to read a text file formatted as below and create a bumpy plane based on the elevation defined in that file. If a line has 10 elevation values, that means the plane will have 10 points along the X axis. If the file has 5 lines, that means the plane will have 5 points along the Y axis.

1 2 3 4 5
5 4 3 2 1
1 2 3 4 5
5 4 3 2 1
1 2 3 4 5

Each number represents an elevation on a uniform grid where a line (horizontal) define the elevations along the X axis. With that in mind, new lines (vertical) define the elevations along the Y axis and the actual number is the elevation along Z.

In order to properly represent that in world coordinates, you can provide an origin which will define the coordinate of the first point without its elevation. Then you need to describe how much you should move along X and Y between two elevations definition. For that we use xSpacing and ySpacing. Since the elevation is given to us as a number, we can scale it via zScaling. Finally you may decide that your grid should move along positive X and negative Y while reading the file. The xDirection and yDirection are meant to give you control on that end.

Methods

extend

Method used to decorate a given object (publicAPI+model) with vtkOBJReader characteristics.

ArgumentTypeRequiredDescription
publicAPIYesobject on which methods will be bounds (public)
modelYesobject on which data structure will be bounds (protected)
initialValuesIOBJReaderInitialValuesNo(default: {})

getBaseURL

getDataAccessHelper

getPointDuplicateIds

Convenient method to get the id of all duplicated points. Relies on a "Duplicates" array that contains the id of: - the first duplicate id for the original point (or self Id if there is no duplicate)

  • the original id for the duplicate points Duplicated points must be adjacent to each other. Example:
    • Points: [pt0, pt1, pt2, pt3, pt1d0, pt1d1, pt1d3, pt3d1, pt3d2]
  • Duplicates: [0, 4, 2, 3, 1, 1, 1, 3, 3] Expected results:
  • getPointDuplicateIds(p, 1) => [1, 4, 5, 6]
  • getPointDuplicateIds(p, 0) => [0]
  • getPointDuplicateIds(p, 5) => [1, 4, 5, 6]
ArgumentTypeRequiredDescription
polydataYesA polydata generated by the OBJReader
pointIdYesA point Id (duplicated or not)

getSplitMode

getTrackDuplicates

True if duplicates are tracked in output polydata.

getUrl

Get the url of the object to load.

invokeBusy

ArgumentTypeRequiredDescription
busyBooleanYes

isBusy

loadData

Load the object data.

ArgumentTypeRequiredDescription
optionsIOBJReaderOptionsNo

newInstance

Method used to create a new instance of vtkOBJReader

ArgumentTypeRequiredDescription
initialValuesIOBJReaderInitialValuesNofor pre-setting some of its content

onBusy

ArgumentTypeRequiredDescription
callbackYes

parseAsText

Parse data as text.

ArgumentTypeRequiredDescription
contentStringYesThe content to parse.

requestData

ArgumentTypeRequiredDescription
inDataYes
outDataYes

setDataAccessHelper

ArgumentTypeRequiredDescription
dataAccessHelperYes

setSplitMode

String in OBJ file used to split in multiple output polydata.

ArgumentTypeRequiredDescription
splitModeNull or StringYes

setTrackDuplicates

Set to true to be able to use getPointDuplicateIds() on output polydata. Requires splitMode to not be null.

ArgumentTypeRequiredDescription
trackDuplicatesYestrue or false (false by default)

setUrl

Set the url of the object to load.

ArgumentTypeRequiredDescription
urlStringYesthe url of the object to load.
optionIOBJReaderOptionsNoThe OBJ reader options.