SolidPy

What is it?

user Brian Beebe,

How do I make this?

1. If you do not have OpenSCAD installed, download the application from openscad.org
   
   

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2. Download the module at github.com/bjbsquared/SolidPy.
   
   

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3. Open your terminal program
   
   

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4. To check that Python is installed on your machine, type:

   python

   you should see something like this:

       Python 2.7.1 (r271:86832, Jul 31 2011, 19:30:53) 
   [GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)] on darwin
   Type "help", "copyright", "credits" or "license" for more information.

   Press CTRL+Z or CTRL+D to exit Python.
   
   If you are unfamiliar with python, here are a few things to keep in mind:
   • Python is not a typed language.
   • Python is case sensitive.
   • The end of a line marks the end of a statement.
   • Single line comments begin with a #
   • Multiline comments begin and end with '''
   • Python source files use the .py extension.

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5. Back in your terminal program set the PYTHONPATH variable:

   $ export PYTHONPATH=$PYTHONPATH:/Users/dir_where_pymodules_lives

   which is appending the path '/Users/dir_where_pymodules_lives' to the environment variable PYTHONPATH.
   
   

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6. Open OpenSCAD
   
   

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7. Select Automatic Reload and Compile to view changes as you run your python script.
   
   

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8. Language Differences between SolidPy and OpenSCAD

   SolidPy	Open SCAD	Difference
   a = Sphere(r=2)	sphere(r=2)	First letter Capitalized
   b = Cube(1,2,3)	cube([1,2,3])	Square brackets are optional
   b.color(“red”,0.5)	color(“red”,0.5) cube([1,2,3])	Objects are transformed using methods
   b = a.copy()	no equivalent	Shapes are objects
   c = a + b	union(){sphere(r=2) cube([1,2,3])}	Easy to read syntax

   
   
   Here are the interfaces for each class. Some commands will allow a single object or a list of objects to be used as an argument: Show Interfaces

   Shapes

   Cube(self, x, y = None, z = None, center = None) or Cube(self, [x,y,z] center = None)

   Returns a SolidPyObj which represents a cube. Examples:

   myBox = Cube([3,4,5])

   or

   myBox = Cube(3,4,5)

   
   
   

   
   
   

   Cylinder(h, r, r2 = None, fa = None, fs = None, fn = None, center = None)

   Returns a SolidPyObj which represents a cylinder.

   myTube = Cylinder(h = 5, r=10, center = True )

   
   
   

   
   
   

   Sphere(r, fa = None, fs = None, fn = None)

   Returns a SolidPyObj which represents a cylinder. Notice that OpenSCAD uses $fs and $fn while SolidPy drops the $.

   myBall = Sphere(r=5)

   
   
   

   
   
   

   DXF_linear_extrude(filename, height, convexity = None, center = None)

   Creates a 3D object by extruding a DXF file. Returns a SolidPyObj object.

   myShape = DXF_linear_extrude(mydxfFile, h=5)

   
   
   

   
   
   

   Linear_extrude(height,center,convexity,twist)

   Extrudes shapes to make 3D object. Returns a SolidPyObj object.
   
   

   
   
   

   Import(fileName)

   Imports a file for use in the current OpenSCAD model. Returns a SolidPyObj object.
   
   

   
   
   

   Module(moduleName,kwargs)

   Calls a OpenSCAD Module brought in by the Use(filename) command. Arguments to the module must be given in keyworded values. Returns a SolidPyObj object.

   Use("Rachet Tooth.scad")
   
   tooth = Module("rachetTooth", ht = 1, thk=8, ra = 16, ba = 80)
       

   
   
   

   
   
   

   Polygon(pointsList, pathList, convexity)

   Returns a SolidPyObj object.
   
   

   
   
   

   Polyhedron(points,triangles)

   Returns a SolidPyObj object.
   
   

   
   
   

   Projection(cut = true)

   Returns a SolidPyObj object.
   
   

   
   
   

   Rotate_extrude(convexity = None, fn = None)

   Returns a SolidPyObj object.
   
   

   
   
   

   CGS Operations

   CGS object hold other SolidPy objects as child objects. They perform the CGS operation on the child objects as described below.

   '+' Operator

    Union()

    Union([solidPyobjs])

    Union(solidObj1 = None, solidObj2 = None)
   

   Union() returns an empty Union() object that can be used to add SolidPy objects at a later time
   
   Union ([objectList]) will create a union that contains the objects in [objectList]
   
   Union ([objectList1], [objectList2]) will create a union that contains the objects in both lists.
   
   An alternate form of Union is the + operator.

       a = Cube(5,5,5)
       b = sphere(r = 6)
       myUnion = a + b
    

   - If 'a' Union() then 'b' is added to the 'a' Union()
   
   - If 'b' Union() then 'a' is added to the 'b' Union()
   
   - If neither ''a or 'b' is a Union then both are added to a new union.
   
   
   
   

   
   
   

   '-' Operator

   Difference(solidObj1 = None, solidObj2 = None)

    Difference()

   Difference([solidPyobjs])

   Difference() returns an empty Difference() that can be used to add SolidPy objects at a later time.
   
   Difference ([objectList]) will create a Difference() that contains the objects in [objectList]
   
   Difference ([objectList1], [objectList2]) will create a Difference() that contains the objects in both lists.
   
   The first object added to the Difference() object is the one that all other will be subtracted from.
   
   An alternate form of Union is the - operator.

       a = Cube(5,5,5)
       b = sphere(r = 6)
       myDiff = a - b
      

   - If 'a' is a Difference() then 'b' is subtracted from the 'a' Difference()
   
   - If 'a' is not a Difference() object a new is made placing 'a' as its first child from which 'b' will be subtracted.
   
   
   
   

   
   
   

   '*' Operator

   Intersection(solidObj1 = None, solidObj2 = None)

   Intersection()

    Intersection([solidPyobjs])

   Intersection() returns an empty Intersection() that can be used to add SolidPy objects at a later time.
   
   Intersection ([objectList]) will create an Intersection() that contains the objects in [objectList]
   
   Intersection ([objectList1], [objectList2]) will create an Intersection that contains the objects in both lists.
   
   The all objects added to the Intersection() object will define the intersection.
   
   An alternate form of Union is the * operator.

       a = Cube(5,5,5)
       b = sphere(r = 6)
       myIntersect = a * b
       

   - If 'a' is an Intersection() then 'b' is intersected with the 'a' Intersection()
   
   - If 'b' is an Intersection() then 'a' is intersected with the 'b' Intersection()
   
   - If 'a' or 'b' are not Intersection() objects, a new one is made.
   
   
   

   
   
   

   Minkowski( solidObj1 = None, solidObj2 = None)

   Returns the Minkowski parent of solidObj1 and solidObj2.
   
   

   
   
   

   Hull(solidObj1 = None, solidObj2 = None)

   Returns the Minkowski parent of solidObj1 and solidObj2.
   
   

   
   
   

   Transforms

   Transforms are methods of SolidPy objects. Transforms are kept in the objects transform stack.

   translate(x,y,z)

   translate([x,y,z])

   SolidPy	Open SCAD
   a = Sphere(r=2)	sphere(r=2)
   a.translate(2,4,6)	translate([2,4,6]){sphere(r=2)}

   
   
   

   
   
   

    mirror(x,y,z)

    mirror([x,y,z])

   SolidPy	Open SCAD
   a = Sphere(r=2)	sphere(r=2)
   a.translate(2,4,6)	translate([2,4,6]){sphere(r=2)}

   
   
   

   
   
   

   multmatrix(m)

   m is a 4x4 matrix.

   SolidPy	Open SCAD
   a = Sphere(r=2)	sphere(r=2)
   a.multmatrix(m)	multmatrix(m){sphere(r=2)}

   
   
   

   
   
   

     scale(x,y,z)

    scale([x,y,z])

   SolidPy	Open SCAD
   a = Sphere(r=2)	sphere(r=2)
   a.scale(2,4,6)	scale([2,4,6]){sphere(r=2)}

   
   
   

   
   
   

   color("color",alpha)

   color([r,g,b],alpha)

   SolidPy	Open SCAD
   a = Sphere(r=2)	sphere(r=2)
   a.color("red", 0.5)	color("red", 0.5){sphere(r=2)}

   
   
   

   
   
   

   Utilities

   Comment

   Each object can have a comment applied to which will help identify it in the OpenSCAD code.

       a=Cube(1,2,3)
       a.comment = "Here is my Cube!"
   

   
   
   

   
   
   

   copy(SolidPyObj)

   Copy creates an exact duplicate of the solid object except the parent of the duplicate is set to `None` and children are duplicates of the original.

        myBox = Cube(4,5,6)
   	 myNewBox = myBox.copy()
   

   
   
   

   
   
   

   use("filename.scad")

   This loads an OpenSCAD file in order to access modules within that file.
   Note that **include()** is not implemented.
   
   

   
   
   

   writeSCADfile(fileName, *args):

   fileName = the SCAD file to save to. Include the '.scad' extension
   *args can be SolidPy objects or lists of SolidPy objects.
   
   

   
   
   

   Extras

   inches(x)

   Everything in OpenSCAD is assumed to be millimeters(mm). inches(X) returns 25.4 * X to convert x that is in inches to mm.

   Modifiers

   Each object has modifiers that are found in OpenSCAD. They are boolean attributes.

   • root
   • disable
   • background
   • debug

   Activate these as needed by:

         a = Cube(1,2,3)
         a.disable = True
     

   Defaults

   Defaults are to be set by the user for their own taste.

   tab

   By default Defaults.tab = " " * 4 This set the tab length in the OpenSCAD code written by writeSCADfile().
   
   

   
   
   

   includeFiles

   Defaults.includeFiles is modified by the Use(filename) command to hold files to be included. It can also be modified directly.
   
   

   
   
   

   fs

   Defaults.fs sets the Special Variable in OpenSCAD $fs at the beginning of the OpenSCAD file.
   
   

   
   
   

   fn

   Defaults.fn sets the Special Variable in OpenSCAD $fn at the beginning of the OpenSCAD file.
   
   

   
   
   

   fa

   Defaults.fa sets the Special Variable in OpenSCAD $fa at the beginning of the OpenSCAD file.
   
   

   
   
   

   autoColor

   When Default.autoColor == True colors are automatically applied to all objects at their creation given by the order set in the Default.color[] list
   
   

   
   
   

   colors

   Defaults.colors are used by the autoColor setting to automatically apply a color to a SolidPy object when it is created.

       Defaults.colors = ["blue", "green", "orange", "yellow", "SpringGreen"]
   

   Colors can be added or changed as required. Colors can be found at OpenSCAD Users Manual.
   Hide Interfaces
   
   

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9. When using SolidPy, start your script with the following line:

   from SolidPy import *
   from SolidPy import SolidPyObj

   and end your script with:

   
   writeSCADfile('name_of_file.scad', variable_to_write)

   
   
   

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Here is an example of a program:

from SolidPy import *
from SolidPy import SolidPyObj

x = 40.0
y = 40.0
z = 10.0
t = 1.0 #thickenss
tol = 0.25
outter = [x, y, z]
inner = [x - t, y - t, z]

outerShell = Cube(outter, center = True)

innerShell = Cube(inner, center = True)

innerShell.translate([0, 0, t])



top = Cube([x + 4 * t, y + 4 * t, t], center = True)

top.translate([0, 0, t])

rim = Cube([x + 2 * t, y + 2 * t, 2 * t],
            center = True) - Cube(x + tol, y + tol, 4 * t,
            center = True)
rim.color('green', 0.5)


top += rim
top.rotate([180, 0, 0])


box = outerShell - innerShell
top.translate(1.5 * x, 0, 0)
box.color('red',1);
boxAndTop = Union(box, top)
writeSCADfile('box.scad', boxAndTop)





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10. Save the file as box.py
    
    

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11. In your terminal program navigate to where you saved your box.py
    
    

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12. Run the program:

    python box.py

    
    
    

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13. Open the output file box.scad
    
    

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14. Make a change in the python script, save, run and watch your OpenSCAD file update.
    
    

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15. Create a new python script to make your own SolidPy shape
    
    

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16. Render and Compile your OpenSCAD form by pressing F6. Then select Design>Export as STL
    
    

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17. Open the STL file in Makerware and prepare the file for printing.
    
    

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Why am I doing this?

Now what?

1. Upload your form that you created with SolidPy to Thingiverse
2. Come back tomorrow for more information and inspiration!