From string to not a string

renderiza

Hi,

I have this problem where I have a string that I want to use as a line of code(not sure what to call it).

Here is my example...

sumx = "v[0].position.x + v[1].position.x + v[2].position.x"

I want sumx to solve that math equation...Is this possible


model = Sketchup.active_model
ents = model.active_entities
sel = model.selection
faces = sel.grep(Sketchup;;Face)
@addx = ["v[0].position.x"]
@addy = ["v[0].position.y"]
@addz = ["v[0].position.z"]

model.start_operation('csplit')

  faces.each do |face|
    v = face.vertices
    num = v.length
    i = 1
    
    while i < num  do
      @addx << " + v[#{i}].position.x"
      @addy << " + v[#{i}].position.y"
      @addz << " + v[#{i}].position.z"
      i += 1
    end
    
    ax = @addx * ","
    sumx = ax.delete ","
    
    ay = @addy * ","
    sumy = ay.delete ","
    
    az = @addz * ","
    sumz = az.delete ","

    cx = sumx # v[0].position.x + v[1].position.x + v[2].position.x ... 
    cy = sumy # v[0].position.y + v[1].position.y + v[2].position.y ...
    cz = sumz # v[0].position.z + v[1].position.z + v[2].position.z ...
    
    px = cx / num
    py = cy / num
    pz = cz / num

    v.each do |vertex|
      p1 = [px, py, pz]
      p2 = vertex
      line = ents.add_line p1,p2
    end
   
  end
  sel.clear
model.commit_operation

Thanks!

renderiza

Yay!

Here is updated code...

model = Sketchup.active_model
ents = model.active_entities
sel = model.selection
faces = sel.grep(Sketchup;;Face)
@addx = ["v[0].position.x"]
@addy = ["v[0].position.y"]
@addz = ["v[0].position.z"]

model.start_operation('csplit')

  faces.each do |face|
    @addx.clear
    @addy.clear
    @addz.clear
    @addx = ["v[0].position.x"]
    @addy = ["v[0].position.y"]
    @addz = ["v[0].position.z"]
 
    v = face.vertices
    num = v.length
    i = 1
   
    while i < num  do
      @addx << " + v[#{i}].position.x"
      @addy << " + v[#{i}].position.y"
      @addz << " + v[#{i}].position.z"
      i += 1
    end
   
    ax = @addx * ","
    sumx = ax.delete ","
   
    ay = @addy * ","
    sumy = ay.delete ","
   
    az = @addz * ","
    sumz = az.delete ","
   
    cx = eval("#{sumx}") # v[0].position.x + v[1].position.x + v[2].position.x
    cy = eval("#{sumy}") # v[0].position.y + v[1].position.y + v[2].position.y
    cz = eval("#{sumz}") # v[0].position.z + v[1].position.z + v[2].position.z
   
    px = cx / num
    py = cy / num
    pz = cz / num

    v.each do |vertex|
      p1 = [px, py, pz]
      p2 = vertex
      line = ents.add_line p1,p2
    end

  end
  sel.clear
model.commit_operation

If you think the code can improve please let me know!

Dan Rathbun

Lines 5,6,7,15,16 & 17 refer to array reference v before the reference is made.

renderiza

Will this cause problem even if v on lines 5,6,7,15,16 & 17 is part of a string and not a variable?

Thanks!

Dan Rathbun

When you ned to have an index var,... replace:

    v = face.vertices
    num = v.length
    i = 1
   
    while i < num  do
      @addx << " + v[#{i}].position.x"
      @addy << " + v[#{i}].position.y"
      @addz << " + v[#{i}].position.z"
      i += 1
    end

... with this (remember that module Enumerable is mixed into class Array) :

    v = face.vertices
    v.each_with_index {|vert,i|
      @addx << " + v[#{i}].position.x"
      @addy << " + v[#{i}].position.y"
      @addz << " + v[#{i}].position.z"
    }

Dan Rathbun

@renderiza said:

Will this cause problem even if v on lines 5,6,7,15,16 & 17 is part of a string and not a variable?

NO.. you are correct. They are just a string char at that point.

So my mistake. (you got me)

renderiza

@dan rathbun said:

NO.. you are correct. They are just a string char at that point.

So my mistake. (you got me)

My life is complete!!!

@dan rathbun said:

... with this (remember that module Enumerable is mixed into class Array) :

    v = face.vertices
>     v.each_with_index {|vert,i|
>       @addx << " + v[#{i}].position.x"
>       @addy << " + v[#{i}].position.y"
>       @addz << " + v[#{i}].position.z"
>     }

That is great! With your suggestion I now don't need to start with an array that has a value!

Here is updated code...

model = Sketchup.active_model
ents = model.active_entities
sel = model.selection
faces = sel.grep(Sketchup;;Face)
@addx = []
@addy = []
@addz = []

model.start_operation('csplit')

  faces.each do |face|
    @addx.clear
    @addy.clear
    @addz.clear

    v = face.vertices
    num = v.length
  
    v.each_with_index {|vert,i|
      @addx << " + v[#{i}].position.x"
      @addy << " + v[#{i}].position.y"
      @addz << " + v[#{i}].position.z"
    }
   
    ax = @addx * ","
    sumx = ax.delete ","
   
    ay = @addy * ","
    sumy = ay.delete ","
   
    az = @addz * ","
    sumz = az.delete ","
   
    cx = eval("#{sumx}")
    cy = eval("#{sumy}")
    cz = eval("#{sumz}")
   
    px = cx / num
    py = cy / num
    pz = cz / num

    v.each do |vertex|
      p1 = [px, py, pz]
      p2 = vertex
      line = ents.add_line p1,p2
    end

  end
  sel.clear
model.commit_operation

I appreciate your help as always Dan!!!

Dan Rathbun

String manipulation is quite slow in Ruby.

How about doing it with no strings?

  def csplit()
    #
    model = Sketchup.active_model
    ents = model.active_entities
    sel = model.selection
    faces = sel.grep(Sketchup;;Face)
    #
    model.start_operation('csplit')
      #
      faces.each do |face|
        #
        sum = Geom;;Point3d.new(0,0,0)
        #
        verts = face.vertices
        n = verts.size.to_f
        # use API Geom;;Point3d.+ instance method;
        verts.each {|v| sum += ORIGIN.vector_to(v.position) }
        #
        avg = Geom;;Point3d.new( sum.x/n, sum.y/n, sum.z/n )
        #
        verts.each {|v| ents.add_line( avg, v ) }
        #
      end # each face
      #
    model.commit_operation
    #
  rescue => e
    #
    puts "Error <#{e.class.name}; #{e.message} >"
    puts e.backtrace if $VERBOSE
    #
    model.abort_operation
    #
  else # when no errors;
    #
    sel.clear
    #
  end # csplit()

FIXED: (line 17) Geom::Point3d#+ cannot take a Geom::Point3d as an arg, even tho the API says it can. Replaced sum += v.position with: sum += ORIGIN.vector_to(v.position)

renderiza

Dan Rathbun I can't thank you enough you sir are brilliant!