Move points to a '3D grid'

[rossthompson]

Hi,

I am trying to write a script for cleaning up geometery created from another program (IES VE). Essentially what I want to achieve is to move each vertex so it sits on a '3D grid'. I believe this could be achieved by applying a rounding function to the X,Y and Z coordinates of each point.

The attached image hopefully illustrates what I am trying to achieve. Ideally the degree of rounding would be a user input variable.

Any help on this would be greatly appreciated.

Ross

[gilles]

You can use the scale tool: begin to scale then type 400mm;400mm;400mm + enter.

Note that the separator may be "," for you .

[thomthom]

You can use the scale tool:

I am trying to write a script

[thomthom]

This is a nice idea - I might implement such a feature in Vertex Tools.

Of the top of my head, something like this:

pt = Geom::Point3d.new( 3.976879, 3.970209, 1.002568 )
grid_pt = pt.to_a.map { |n| n.round() }
v = pt.vector_to( grid_pt )

You can do something like that - iterate the vertices of a mesh, for each vertex find the nearest grid position to the vertex, collect the vertex and adjustment vector to each their array and use Entities.transform_by_vectors https://developers.google.com/sketchup/ ... by_vectors

Note that this simple example rounded to nearest whole number. Modifications is needed to account for grids fitted to decimal precision.

[thomthom]

Actually, that example will round to nearest inch - which is SketchUp's internal unit...

[thomthom]

Code: Select all

pt = Geom::Point3d.new( 3.976879.m, 3.760209.m, 1.002568.m )
tolerance = 0.25.m
grid_pt = pt.to_a.map { |n|
  b = ( n / tolerance ).to_i * tolerance
  r = n % tolerance
  (r > tolerance / 2) ? b + tolerance : b
}
grid_pt = Geom::Point3d.new( *grid_pt )

puts "Original: #{pt}"
puts "Tolerance: #{tolerance}"
puts "Grid Point: #{grid_pt}" 

Output:
Original: (3976,879mm, 3760,209mm, 1002,568mm)
Tolerance: 250mm
Grid Point: (4000mm, 3750mm, 1000mm)

[thomthom]

Test module - adjust the vertices in the active context to grid.

Code: Select all

module GridSnap

  def self.round_point( point, tolerance )
    grid_pt = point.to_a.map { |n|
      b = ( n / tolerance ).to_i * tolerance
      r = n % tolerance
      (r > tolerance / 2) ? b + tolerance : b
    }
    Geom::Point3d.new( *grid_pt )
  end
  
  def self.test_it
    pt = Geom::Point3d.new( 3.976879.m, 3.760209.m, 1.002568.m )
    tolerance = 0.25.m
    grid_pt = self.round_point( pt, tolerance )
    
    puts "Original: #{pt}"
    puts "Tolerance: #{tolerance}"
    puts "Grid Point: #{grid_pt}"
  end
  
  def self.adjust_vertices( tolerance = 0.25.m )
    model = Sketchup.active_model
    vertices = []
    # Collect vertices.
    for e in model.active_entities
      vertices << e.vertices if e.is_a?( Sketchup::Edge )
    end
    vertices.flatten!
    vertices.uniq!
    # Calculate grid adjustments.
    vectors = []
    entities = []
    for vertex in vertices
      pt = vertex.position
      grid_pt = self.round_point( pt, tolerance )
      vector = pt.vector_to( grid_pt )
      next unless vector.valid?
      entities << vertex
      vectors << vector
    end
    # Apply transformations
    model.active_entities.transform_by_vectors( entities, vectors )
    puts "#{entities.size} adjusted to grid."
  end

end


[Dan Rathbun]

How about that ??

... from concept to module in under a hour.

[TIG]

Could this then be a tiny step towards a poly-reducer?
As the vertices are 'rationalized' onto a 'grid' some faces could become coplanar and therefore the superfluous shared edges could be removed.
The fineness/coarseness of this 'grid' removes less/more 'detailing'...

[thomthom]

Cubificator?

I was thinking it might be usable to repair troublesome model imported from CAD drawings. Occasionally I run into models where splitting a face with an edge results in duplicate faces. I suspect its due to some precision errors. Maybe if the vertices where adjusted to fit to a finely grained 3D grid the troubles would go away... ?

[rossthompson]

ThomThom thanks so much for your support! I have had a go at running your test module. My understanding is that it should shift the points in the active selection to a 0.25m grid as specified in the code.

However I am having problems running the module. I have attempted to add it to the tools menu as below, but I am not 100% sure how to 'call' the routine. Appologies if I'm being an idiot - I am new to ruby scripting!

Code: Select all

    module GridSnap

      def self.round_point( point, tolerance )
        grid_pt = point.to_a.map { |n|
          b = ( n / tolerance ).to_i * tolerance
          r = n % tolerance
          (r > tolerance / 2) ? b + tolerance : b
        }
        Geom::Point3d.new( *grid_pt )
      end
     
      def self.test_it
        pt = Geom::Point3d.new( 3.976879.m, 3.760209.m, 1.002568.m )
        tolerance = 0.25.m
        grid_pt = self.round_point( pt, tolerance )
       
        puts "Original: #{pt}"
        puts "Tolerance: #{tolerance}"
        puts "Grid Point: #{grid_pt}"
      end
     
      def self.adjust_vertices( tolerance = 0.25.m )
        model = Sketchup.active_model
        vertices = []
        # Collect vertices.
        for e in model.active_entities
          vertices << e.vertices if e.is_a?( Sketchup::Edge )
        end
        vertices.flatten!
        vertices.uniq!
        # Calculate grid adjustments.
        vectors = []
        entities = []
        for vertex in vertices
          pt = vertex.position
          grid_pt = self.round_point( pt, tolerance )
          vector = pt.vector_to( grid_pt )
          next unless vector.valid?
          entities << vertex
          vectors << vector
        end
        # Apply transformations
        model.active_entities.transform_by_vectors( entities, vectors )
        puts "#{entities.size} adjusted to grid."
      end

    end

# Menu Entry:

UI.menu("Tools").add_item("GridSnap") { GridSnap } if not file_loaded?("GridSnap.rb")
file_loaded("GridSnap.rb")




I think this could be a very useful tool for cleaning many types of imported geometry.

Ross

[Dan Rathbun]

Cubificator?

Polyhedronizer ?

Orthogonizer ?

Orthographizer ?

OrthograFixer ?

[TIG]

In case TT is away...
Inside the code making the menu use
{GridSnap.adjust_vertices(1.cm)}
It affects the whole model.
This example uses 1cm grid
Use another 'tolerance' if desired...
If you use () it defaults to 0.25m anyway...
It's only some example code and could be better assembled into something working on a selection with warnings and an 'undo' ???

[TIG]

Not sure this reduced poly rock is so good ?

Cuboidalizer.PNG

'Cuboidalizer' is another name idea too... that or 'Discombobulizer'

[Dan Rathbun]

Here's a beta version with an inputbox and undo operation...

It seemed to only change a cubes vertices in the Z axis ??

Code: Select all

module GridSnap

  @@last_tolerance = 0.25.m

  class << self # PROXY CLASS

    def round_point( point, tolerance )
      grid_pt = point.to_a.map { |n|
        b = ( n / tolerance ).to_i * tolerance
        r = n % tolerance
        (r > tolerance / 2) ? b + tolerance : b
      }
      Geom::Point3d.new( *grid_pt )
    end
   
    def test_it
      pt = Geom::Point3d.new( 3.976879.m, 3.760209.m, 1.002568.m )
      tolerance = @@last_tolerance
      grid_pt = round_point( pt, tolerance )
     
      puts "Original: #{pt}"
      puts "Tolerance: #{tolerance}"
      puts "Grid Point: #{grid_pt}"
    end
   
    def adjust_vertices( tolerance = @@last_tolerance )
      model = Sketchup.active_model
      vertices = []
      # Collect vertices.
      for e in model.active_entities
        vertices << e.vertices if e.is_a?( Sketchup::Edge )
      end
      vertices.flatten!
      vertices.uniq!
      # Calculate grid adjustments.
      vectors = []
      entities = []
      for vertex in vertices
        pt = vertex.position
        grid_pt = round_point( pt, tolerance )
        vector = pt.vector_to( grid_pt )
        next unless vector.valid?
        entities << vertex
        vectors << vector
      end
      # Apply transformations
      model.active_entities.transform_by_vectors( entities, vectors )
      puts "#{entities.size} adjusted to grid."
    end
   
    def menu_command()
      title   = 'Adjust Vertices'
      prompt  = 'Tolerance'
      default = @@last_tolerance
     
      result = UI.inputbox([prompt],[@@last_tolerance],title) rescue @@last_tolerance
      if result
        begin
          ###
          Sketchup.active_model.start_operation("#{title} (#{Sketchup.format_length(result[0])})")
          #
          adjust_vertices( result[0] )
          #
          ###
          Sketchup.active_model.commit_operation()
        rescue
          Sketchup.active_model.abort_operation()
        else
          @@last_tolerance = result[0]
        end
      end
    end

  end # PROXY CLASS
 
  #{# RUN ONCE
  #
  unless file_loaded?("GridSnap.rb")
   
    # Menu Entry:
    UI.menu("Tools").add_item("GridSnap") { menu_command() }
   
    file_loaded("GridSnap.rb")
 
  end #}

end # module



[thomthom]

It seemed to only change a cubes vertices in the Z axis ??

Should apply to X,Y and Z... Seemed to work correctly in my quick test...

[daiku]

Cubificator?

Polyhedronizer ?

Orthogonizer ?

Orthographizer ?

OrthograFixer ?

It's like Autotune for cad! They can make you sound good, even if you can't sing.
If you are editing digital music, and you need to make the drum beats perfect, you can move the beats to the nearest sixteenth note, or whatever. It's call "quantizing".

[Dan Rathbun]

It's called "quantizing".

TRUE !!

Restriction to discrete values (or multiples thereof,) rather than any values in the set of possibles (real numbers, in this case.)

So.. the long term:
Vertex Positional Quantization

The short form:
Vertex to Grid

[rossthompson]

Hi guys, I have had a play with Dan's Beta version and for me it works really well. The verticies are adjusted in X,Y and Z directions and the undo function works fine!

The only slight problem: it adjusts all the geometry in the model, rather than just the active selection. The original module just adjusted the active selection.

Any ideas?

Again thanks for the support - this script should be a realy time saver!

Ross

[Dan Rathbun]

Well .. I did not think I changed the context of what Thomas' code did... just tried to wrap the code properly and added the menu_command() method to handle an inputbox.

I'll have a look at it.. again.

(And it's not really MY edition just because I added the inputbox.. it's still Thomas' thing.)

[Dan Rathbun]

OK... added support for a selection. (Pssst! ... there was no selection support from the beginning Ross.)

This utility should probably be wrapped in Thomas' toplevel author module, and reside below his author directory in some manner.

I'll leave those choices up to him, and when he releases version 1.0.0, we'll delete these beta versions in this thread and put in a link to the release thread.

Code: Select all

#  ==========================================================================
#  GridSnap.rb
#  --------------------------------------------------------------------------
#  by Thomas Thomassen
#
#  --------------------------------------------------------------------------
#  THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
#  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
#  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
#  --------------------------------------------------------------------------
#
#  This utility quantizes the vertex locations, of the current selection,
#    of the model, or just the current context, to a 3D grid, whose interval
#    can be set via a popup inputbox.
#
#  --------------------------------------------------------------------------
#  Revisions:
#
#   0.1.0 : 2012-03-26 : by Thomas Thomassen
#   |
#   initial beta release
#
#   0.2.0 : 2012-03-26 : by Dan Rathbun
#   |
#   + Added menu_command() method for inputbox and undo operation.
#
#   0.3.0 : 2012-03-28 : by Dan Rathbun
#   |
#   + Revised the menu_command() method to pass a selection set to the
#       adjust_vertices() method as a 2nd argument.
#
#  ==========================================================================

module GridSnap

  @@last_tolerance = 0.25.m

  class << self # PROXY CLASS

    def round_point( point, tolerance )
      grid_pt = point.to_a.map { |n|
        b = ( n / tolerance ).to_i * tolerance
        r = n % tolerance
        (r > tolerance / 2) ? b + tolerance : b
      }
      Geom::Point3d.new( *grid_pt )
    end
   
    def test_it
      pt = Geom::Point3d.new( 3.976879.m, 3.760209.m, 1.002568.m )
      tolerance = @@last_tolerance
      grid_pt = round_point( pt, tolerance )
     
      puts "Original: #{pt}"
      puts "Tolerance: #{tolerance}"
      puts "Grid Point: #{grid_pt}"
    end
   
    def adjust_vertices( tolerance = @@last_tolerance, ents = nil )
      model = Sketchup.active_model
      vertices = []
      # determine the context:
      ents = model.active_entities() if ents.nil?
      # Collect vertices.
      for e in ents #model.active_entities
        vertices << e.vertices if e.is_a?( Sketchup::Edge )
      end
      vertices.flatten!
      vertices.uniq!
      # Calculate grid adjustments.
      vectors = []
      entities = []
      for vertex in vertices
        pt = vertex.position
        grid_pt = round_point( pt, tolerance )
        vector = pt.vector_to( grid_pt )
        next unless vector.valid?
        entities << vertex
        vectors << vector
      end
      # Apply transformations
      model.active_entities.transform_by_vectors( entities, vectors )
      puts "#{entities.size} adjusted to grid."
    end
   
    def menu_command()
      title   = 'Adjust Vertices'
      prompt  = 'Tolerance'
      default = @@last_tolerance
     
      result = UI.inputbox([prompt],[@@last_tolerance],title) rescue @@last_tolerance
      if result
        model = Sketchup.active_model
        begin
          ###
          model.start_operation("#{title} (#{Sketchup.format_length(result[0])})")
            #
            if model.selection.empty?
              adjust_vertices( result[0] )
            else
              adjust_vertices( result[0], model.selection.to_a() )
            end
            #
          model.commit_operation()
          ###
        rescue
          model.abort_operation()
        else
          @@last_tolerance = result[0]
        end
      end
    end

  end # PROXY CLASS
 
  #{# RUN ONCE
  #
  unless file_loaded?("GridSnap.rb")
   
    # Menu Entry:
    UI.menu("Tools").add_item("GridSnap") { menu_command() }
   
    file_loaded("GridSnap.rb")
 
  end #}

end # module