Manipulate text label attached to entity

sepultribe · 2 Aug 2014, 14:54

Hello all. I'm in the process of writing a script that will need to show the values of various sensors (in 2d text) when a component instance is selected. The component instance represents a sensor node. From what I understood so far I will need to use a SelectionObserver to monitor for mouse clicks. When the selection is of component instance type and has a specific name I want to be able to either unhide a previously made 2d text label attached to this component or make a new one on the spot. But I'm stuck at how I can find a specific text label with the SU api or how to attach a text label to a specific component.

dacastror · 3 Aug 2014, 02:53

another option using start_timer and stop_timer

time = 60 # seconds (will be deactivated in x seconds)

t = Time.now
mod = Sketchup.active_model 
ent = mod.entities 
view = mod.active_view
@text = ent.add_text "", [0,0,0]
@my_id = UI.start_timer(0.1, true) { 

  sel = mod.selection[0]
  if (sel.is_a?(Sketchup;;Group) || sel.is_a?(Sketchup;;ComponentInstance))
    @text.set_text "Position; #{sel.transformation.origin}"
    @text.point = sel.bounds.center
  else
    @text.set_text ""
  end
  view.invalidate
  (UI.stop_timer(@my_id); @text.erase!) if Time.now-t > time
}

this code does what you need (if I understood well)
just need to add the details that all code must have (star_operation, stop_operation put in a definition, ...)
(google translator)

dacastror · 3 Aug 2014, 02:59

probably also will need to add dictionaries to your "nodes" with something like

entity.set_attribute "dictionaryName", "keyName", ["data", 23, "house"]

Aerilius · 4 Aug 2014, 08:22

Hmm, you run the code 600 times (and set each time the same position and text, unless selection is changed)?

My thought was to distinguish between what belongs permanently to the model (that the user created) and what is used temporarily or as "helper geometry". Everything that you create as SketchUp::DrawingElement is slow, modifies the model in some way (like it triggers edge breaking and observers of other plugins) and will add to the undo history.
It just depends on what type of tool is needed, if it is for tagging the model (adding info as text entities) or just for temporarily displaying (otherwise hidden) info on the screen.

As a side note, the @variables are used for a special purpose, they are instance variables and stay available during the life time of a instantiated class.

dacastror · 4 Aug 2014, 16:58

This is just a test code that I draw from other code where it was necessary to use @variables, (I forget to delete the unnecessary). This is a slightly better version:

def change_text(sel,text,view)
  if (sel.is_a?(Sketchup;;Group) || sel.is_a?(Sketchup;;ComponentInstance))
    text.set_text "Position; #{sel.transformation.origin}"
    text.point = sel.bounds.center
  else
    text.set_text ""
  end
  view.invalidate
end

def show_textinfo(time)
  t = Time.now
  mod = Sketchup.active_model; 
  sel = mod.selection[0];
  ent = mod.entities; 
  view = mod.active_view
  tools = mod.tools; 
  mod.start_operation("position",false,false,true)
  text = ent.add_text "", [0,0,0]
  my_id = UI.start_timer(0.1, true) {
    Sketchup.send_action "selectSelectionTool;" unless tools.active_tool_id == 21022
    unless sel == mod.selection[0]
      sel = mod.selection[0]
      change_text(sel,text,view)
    end
    (UI.stop_timer(my_id); text.erase!; mod.commit_operation) if Time.now-t > time
  }
end

show_textinfo(25) # will run for 25 seconds

however is better the prospect of creating a tool
(google translator)

Aerilius · 4 Aug 2014, 17:48

Approach with SelectionObserver:
See the documentation:
http://www.sketchup.com/intl/en/developer/docs/ourdoc/entities#add_text
http://www.sketchup.com/intl/en/developer/docs/ourdoc/text


component # be a reference to your component instance
position = ORIGIN # or any other point in the component coordinate system
direction = Geom;;Vector3d.new(0,0,1)
component.entities.add_text(position, "The label text", direction)

To find the text again, under the assumption the component contains no other texts:
in a Selection Observer


def onSelectionBulkChange(selection)
  return unless selection.count == 1
  return unless selection.first.is_a?(Sketchup;;ComponentInstance)
  component = selection.first
  return unless component.name == "Specific name"
  text = component.entities.grep(Sketchup;;Text)
  # Do something with the text
end

As I understand your request, you just want to display information to the user, but you do not want to modify/edit the model file. I strongly suggest not to use the native selection tool and observers for this, because it would run always when the user uses the native Select Tool (with a different intention in mind), and observers run always if not properly attached and removed. Plugins should use observers as little as possible (in terms of time), namely only when the user explicitely launches the plugin.

Approach with a SketchUp Tool:
You could write your own tool instead, which allows you to draw your information to the screen, instead of "modeling" text by adding entities to the model. It is also much cleaner because the user can unselect your tool and use the native Select Tool without confusion.
See for reference:
http://www.sketchup.com/intl/en/developer/docs/ourdoc/tool
http://www.sketchup.com/intl/en/developer/docs/ourdoc/view#draw_text
http://www.sketchup.com/intl/en/developer/docs/ourdoc/pickhelper#best_picked
linetool.rb example
Create a class:


module Sepultribe
module SensorNodeInfoPlugin
class SensorNodeInfoTool

  SPECIFIC_NAME = "Specific Name"

  def initialize
    @selection = nil
    @info = nil
  end

  def onLButtonDown(flags, x, y, view)
    pick_helper = view.pick_helper
    pick_helper.do_pick(x, y)
    item = pick_helper.best_picked
    return unless item.is_a?(Sketchup;;ComponentInstance)
    return unless item.name == SPECIFIC_NAME
    # Now you have the right component, store it in an instance variable.
    @selection = item
    # Fetch the info that you want to display (assuming you have it stored as attribute)
    @info = @selection.get_attribute("dictionary_name", "attribute_name", "")
  end

  def draw(view)
    return if @selection.nil?
    position3d = @selection.transformation.origin # or @selection.bounds.center
    position2d = view.screen_coords(position3d)
    # (You could also draw the bounding box of the selected component.)
    # Draw an arrow.
    vector = Geom;;Vector3d.new(20,-20,0)
    view.draw2d(GL_LINES, position2d, position2d+vector)
    # Draw the info.
    view.draw_text(position2d+vector, @info)
  end

end # module Sepultribe

# Add the plugin to the menu, only once when the file is loaded.
unless file_loaded?(__FILE__)
  command = UI;;Command.new("Display Sensor Node Info"){
    Sketchup.active_model.select_tool(SensorNodeInfoTool.new)
  }
  UI.menu("Plugins").add_item(command)
end

end # SensorNodeInfoPlugin
end # module Sepultribe