Drawing Workbench

The Drawing module allows you to put your 3D work on paper. That is, to put views of your models in a 2D window and to insert that window in a drawing, for example a sheet with a border, a title and your logo and finally print that sheet. The Drawing module is currently under construction and more or less a technology preview!

GUI Tools

In the picture you see the main concepts of the Drawing module. The document contains a shape object (Schenkel) which we want to extract to a drawing. Therefore a "Page" is created. A page gets instantiated through a template, in this case the "A3_Landscape" template. The template is an SVG document which can hold your usual page frame, your logo or comply to your presentation standards.

In this page we can insert one or more views. Each view has a position on the page (Properties X,Y), a scale factor (Property scale) and additional properties. Every time the page or the view or the referenced object changes the page gets regenerated and the page display updated.

Scripting

At the moment the end user(GUI) workflow are very limited, so the scripting API is more interesting. Here follows examples on how to use the scripting API of the drawing module.

Simple example

First of all you need the Part and the Drawing module:

import FreeCAD, Part, Drawing

Create a small sample part

Part.show(Part.makeBox(100,100,100).cut(Part.makeCylinder(80,100)).cut(Part.makeBox(90,40,100)).cut(Part.makeBox(20,85,100)))

Direct projection. The G0 means hard edge, the G1 is tangent continuous.

Shape = App.ActiveDocument.Shape.Shape
[visibleG0,visibleG1,hiddenG0,hiddenG1] = Drawing.project(Shape)
print "visible edges:", len(visibleG0.Edges)
print "hidden edges:", len(hiddenG0.Edges)

Everything was projected on the Z-plane:

print "Bnd Box shape: X=",Shape.BoundBox.XLength," Y=",Shape.BoundBox.YLength," Z=",Shape.BoundBox.ZLength
print "Bnd Box project: X=",visibleG0.BoundBox.XLength," Y=",visibleG0.BoundBox.YLength," Z=",visibleG0.BoundBox.ZLength

Different projection vector

[visibleG0,visibleG1,hiddenG0,hiddenG1] = Drawing.project(Shape,Base.Vector(1,1,1))

Project to SVG

resultSVG = Drawing.projectToSVG(Shape,App.Vector(1,1,1))
print resultSVG

The parametric way

Insert a Page object and assign a template

App.activeDocument().addObject('Drawing::FeaturePage','Page')
App.activeDocument().Page.Template = App.ConfigGet('AppHomePath')+'Mod/Drawing/Templates/A3_Landscape.svg'

Create a view on the "Shape" object, define the position and scale and assign it to a Page

App.activeDocument().addObject('Drawing::FeatureViewPart','View')
App.activeDocument().View.Source = App.activeDocument().Shape
App.activeDocument().View.Direction = (0.0,0.0,1.0)
App.activeDocument().View.X = 10.0
App.activeDocument().View.Y = 10.0
App.activeDocument().Page.addObject(App.activeDocument().View)

Create a second view on the same object but this time the view will be rotated by 90 degrees.

App.activeDocument().addObject('Drawing::FeatureViewPart','ViewRot')
App.activeDocument().ViewRot.Source = App.activeDocument().Shape
App.activeDocument().ViewRot.Direction = (0.0,0.0,1.0)
App.activeDocument().ViewRot.X = 290.0
App.activeDocument().ViewRot.Y = 30.0
App.activeDocument().ViewRot.Scale = 1.0
App.activeDocument().ViewRot.Rotation = 90.0
App.activeDocument().Page.addObject(App.activeDocument().ViewRot) 

Create a third view on the same object but with an isometric view direction. The hidden lines are activated too.

App.activeDocument().addObject('Drawing::FeatureViewPart','ViewIso')
App.activeDocument().ViewIso.Source = App.activeDocument().Shape
App.activeDocument().ViewIso.Direction = (1.0,1.0,1.0)
App.activeDocument().ViewIso.X = 335.0
App.activeDocument().ViewIso.Y = 140.0
App.activeDocument().ViewIso.ShowHiddenLines = True
App.activeDocument().Page.addObject(App.activeDocument().ViewIso) 

Change something and update. The update process changes the view and the page.

App.activeDocument().View.X = 30.0
App.activeDocument().View.Y = 30.0
App.activeDocument().View.Scale = 1.5
App.activeDocument().recompute()

Accessing the bits and pieces

Get the SVG fragment of a single view

ViewSVG = App.activeDocument().View.ViewResult
print ViewSVG

Get the whole result page (it's a file in the document's temporary directory, only read permission)

print "Resulting SVG document: ",App.activeDocument().Page.PageResult
file = open(App.activeDocument().Page.PageResult,"r")
print "Result page is ",len(file.readlines())," lines long"

Important: free the file!

del file

Insert a view with your own content:

App.activeDocument().addObject('Drawing::FeatureView','ViewSelf')
App.activeDocument().ViewSelf.ViewResult = """<g id="ViewSelf"
  stroke="rgb(0, 0, 0)"
  stroke-width="0.35"
  stroke-linecap="butt"
  stroke-linejoin="miter"
  transform="translate(30,30)"
  fill="#00cc00"
  >

  <ellipse cx="40" cy="40" rx="30" ry="15"/>
  </g>
"""
App.activeDocument().Page.addObject(App.activeDocument().ViewSelf)
App.activeDocument().recompute()

del Shape,ViewSVG, resultSVG

That leads to the following result: