Call out distances of user snapped points from the camera point in a viewport

DistanceFromCamera.py

#! python3

import rhinoscriptsyntax as rs
import scriptcontext as sc

import System
import Rhino

def DistanceFromCamera():
    #color = System.Drawing.Color.Black
    colors = [System.Drawing.Color.Black, System.Drawing.Color.AntiqueWhite]
    colorList = ["Black", "White"]
    def GetPointDynamicDrawFunc( sender, args ):
        color = colors[colorIdx]
        for i in range(len(pts)):
            tempPlane = tPlane
            tempPlane.Origin = pts[i]
            args.Display.DrawPoint(pts[i])
            
            args.Display.Draw3dText(str(dists[i]), color, tempPlane, labelSize, "Arial Black", True, True)

    viewRC,view = Rhino.Input.RhinoGet.GetView("Select a view to test.")
    if viewRC != Rhino.Commands.Result.Success:
        return

    vp = view.ActiveViewport
    planeRC, tPlane = vp.GetCameraFrame()
    cam = vp.CameraLocation

    pts = []
    dists = []
    while True:

        blnLabel=True
        if 'LABEL_DIST' in sc.sticky:
            blnLabel = sc.sticky['LABEL_DIST']

        labelSize = 10
        if 'LABEL_SIZE' in sc.sticky:
            labelSize = sc.sticky['LABEL_SIZE']

        colorIdx = 0
        if 'COLOR_IDX' in sc.sticky:
            colorIdx = sc.sticky['COLOR_IDX']

        gp = Rhino.Input.Custom.GetPoint()
        
        gp.AcceptNumber(True, True)

        opLabel = Rhino.Input.Custom.OptionToggle(blnLabel, "No", "Yes")
        gp.AddOptionToggle("ShowLabels", opLabel)


        opLabelSize = Rhino.Input.Custom.OptionDouble(labelSize)
        gp.AddOptionDouble("LabelTextHeight",opLabelSize)

        gp.AddOption("ToggleColor")

        if len(pts) > 0:
            gp.AddOption("Undo")

        if len(pts) > 0:
            if blnLabel:
                gp.DynamicDraw += GetPointDynamicDrawFunc

        rc = gp.Get()

        if( gp.CommandResult() != Rhino.Commands.Result.Success ):
            break
        if rc == Rhino.Input.GetResult.Point:

            pt = gp.Point()
            pts.append(pt)

        elif rc == Rhino.Input.GetResult.Option:
            idx = gp.OptionIndex()
            blnLabel = opLabel.CurrentValue
            sc.sticky['LABEL_DIST'] = blnLabel
            labelSize = opLabelSize.CurrentValue
            sc.sticky['LABEL_SIZE'] = labelSize

            if idx ==3:
                if colorIdx == 0:
                    colorIdx = 1
                else:
                    colorIdx = 0
                sc.sticky['COLOR_IDX'] = colorIdx
                continue

            if idx == 4:
                pts.pop()
                dists.pop()
            continue

        elif rc == Rhino.Input.GetResult.Number:
            num = gp.Number()
            if num > 0:
                labelSize = num
                sc.sticky['LABEL_SIZE'] = labelSize
            continue
        else:
            return

        if not pt:
            return

        dist = round(pt.DistanceTo(cam), 2)
        dists.append(dist)

        print("Distance from camera = " + str(dist))

DistanceFromCamera()