draw line in 3D

Question

Hello, how to draw simple line from point A to point B in 3D, I need to draw simple line from player to collision point. Need some tips how to "draw" in 3D space.
Thank you!

Answer 1

There is a demo drawing line in 3d.
Download demos and see in demos/3d/navmesh.
You can see a line when moving character if var draw_path = true.

Comments

thanks, I will look at that demo

Answer 2

Here is what I'm using now. You AutoLoad the script then can call it by:

ScriptName.Draw_Line3D(id, vector_a, vector_b, color, thickness)

Code:

extends Node2D

class Line:

    var id
    var color
    var thickness
    var a = Vector2()
    var b = Vector2()

var Lines
var Camera_Node

func _ready():

    Camera_Node = get_viewport().get_camera()

    Lines = []
    set_process(true)

func _draw():

    for line in Lines:

        draw_line(line.a, line.b, line.color, line.thickness)

func _process(delta):

    update()

func Draw_Line3D(id, vector_a, vector_b, color, thickness):

    for line in Lines:
        if line.id == id:
            line.color = color
            line.a = Camera_Node.unproject_position(vector_a)
            line.b = Camera_Node.unproject_position(vector_b)
            line.thickness = thickness
            return

    var new_line = Line.new()
    new_line.id = id
    new_line.color = color
    new_line.a = Camera_Node.unproject_position(vector_a)
    new_line.b = Camera_Node.unproject_position(vector_b)
    new_line.thickness = thickness

    Lines.append(new_line)

Remove_Line(id):

        var i = 0
        var found = false
        for line in Lines:

            if line.id == id:
                found = true
                break
            i += 1

        if found:

            Lines.remove(i)

Comments

This script is very nice but you might want to unproject the positions insde the draw function so that lines stay at their original world position when the camera moves.

---

Nice I've updated your code so it update with camera movement, the only problem is if the lines go behind the camera they get inverted and show up going away from the camera. I'm only using it for debug purposes so I don't necessarily mind that it happens
Code:

extends Node2D
class Line:
var id
var color
var thickness
var a3d = Vector3()
var b3d = Vector3()
var a = Vector2()
var b = Vector2()
var Lines
var CameraNode
func _ready():
CameraNode = getviewport().getcamera()
Lines = []
set_process(true)

func draw():
for line in Lines:
line.a = CameraNode.unprojectposition(line.a3d)
line.b = CameraNode.unprojectposition(line.b3d)
drawline(line.a, line.b, line.color, line.thickness)
func _process(delta):
update()

func DrawLine3D(id, vectora, vectorb, color, thickness):
for line in Lines:
if line.id == id:
line.color = color
line.a3d = vectora
line.b3d = vectorb
line.a = CameraNode.unprojectposition(vectora)
line.b = CameraNode.unprojectposition(vectorb)
line.thickness = thickness
return
var newline = Line.new()
newline.id = id
newline.color = color
newline.a = CameraNode.unprojectposition(vectora)
newline.b = CameraNode.unprojectposition(vectorb)
newline.thickness = thickness
Lines.append(newline)
func Remove_Line(id):
var i = 0
var found = false
for line in Lines:
if line.id == id:
found = true
break
i += 1
if found:
Lines.remove(i)

Answer 3

If someone was searching for 3D line that allows you to have texture on it then you can try this: https://github.com/jegor377/Line3D

Answer 4

This is how I am drawing lines. This draws a line for each pair of Vector3 in the list points. Change Mesh.PrimitiveType.Lines to Mesh.PrimitiveType.LineStrip for a continues line between each point.

using Godot;
using System.Collections.Generic;

namespace Utility
{
    class LineDrawer3d : ImmediateGeometry
    {
        List<Vector3> points = new List<Vector3>();


        public void addLine(Vector3 p1, Vector3 p2)
        {
            points.Add(p1);
            points.Add(p2);
        }


        public override void _Process(float delta)
        {
            base._Process(delta);

            Clear();

            Begin(Mesh.PrimitiveType.Lines);

            for (int i = 0; i < points.Count; ++i)
            {
                AddVertex(points[i]);
            }

            End();
        }
    }
}