How to draw a line using script

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How can I draw a line using script?

Answer 1

Best Answer

Answer by robert · Nov 27, 2009 at 08:56 AM

You can either use a LineRenderer (also from a script) for a line drawn on a camera-facing stripe of quads or you can use good'ol GL.Begin(GL.LINES) to have the traditional rasterization to a line of pixels.

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yoyo · Jan 31, 2011 at 05:17 PM 1

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Note that the GL class is only available with Unity Pro, and doesn't work on the iPhone.

Hoschomatic · Aug 01, 2013 at 03:18 PM 9

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GL Class is working in free version unity 4.0 and higher

yoyo · Aug 18, 2013 at 03:39 AM 1

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cool, thanks for pointing that out

Answer 2

Answer by paranoidray · Dec 06, 2015 at 08:55 PM

 void DrawLine(Vector3 start, Vector3 end, Color color, float duration = 0.2f)
         {
             GameObject myLine = new GameObject();
             myLine.transform.position = start;
             myLine.AddComponent<LineRenderer>();
             LineRenderer lr = myLine.GetComponent<LineRenderer>();
             lr.material = new Material(Shader.Find("Particles/Alpha Blended Premultiply"));
             lr.SetColors(color, color);
             lr.SetWidth(0.1f, 0.1f);
             lr.SetPosition(0, start);
             lr.SetPosition(1, end);
             GameObject.Destroy(myLine, duration);
         }

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AlexWei · Jun 22, 2016 at 09:14 AM 0

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Useful. Nice and clean solution.

dreg_master AlexWei · Apr 14, 2017 at 09:04 AM 0

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Agreed.. with what this dude said

Lord_Atrix · Jun 28, 2016 at 01:57 PM 0

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Simple and easy to use code.

I got cought out with this, my own fault. I wasnt exporting the shader so need to make sure that the Shader.Find("Particles/Alpha Blended Premultiply") is set within the unity environment so it gets compiled with the release build. Or if not make sure you are exporting the shader with the release build.

so for clarity for $$anonymous$$e i did:

public Shader lineShader;

and then in the editer selected the shader I wanted

dnyaneshwar_unity · Oct 08, 2018 at 10:23 AM 0

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Unable to add separate line my script is :

if (((Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.$$anonymous$$oved) || Input.Get$$anonymous$$ouseButton(0))) { Plane objPlane = new Plane(Camera.main.transform.forward * -1, this.transform.position); Ray mRay = Camera.main.ScreenPointToRay(Input.mousePosition); float rayDistance; if (objPlane.Raycast(mRay, out rayDistance)) this.transform.position = mRay.GetPoint(rayDistance); }

gamemakerdude15145 · Jul 18, 2020 at 02:01 PM 0

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SetColors and SetWidth are deprecated. Good answer, though.

Answer 3

Answer by Goody! · Nov 28, 2009 at 12:27 AM

A simple one is debug.drawline.

Below from: http://unity3d.com/support/documentation/ScriptReference/Debug.DrawLine.html

Debug.DrawLine
static function DrawLine (start : Vector3, end : Vector3, color : Color = Color.white) : void Description

Draws a line from the point start to end with color.

The line will be drawn in the scene view of the editor. If gizmo drawing is enabled in the game view, the line will also be drawn there.

// Draws a red line from the the world-space origin to the point (1, 0, 0)
function Update () {
Debug.DrawLine (Vector3.zero, new Vector3 (1, 0, 0), Color.red);
}

Btw, in case you didn't know, a vector3 is a point in space representing x,y,z.

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Answer 4

Answer by crystalfish · Oct 29, 2013 at 10:16 AM

Gizmos.DrawLine() , Debug.DrawLine(),GL.Begin(GL.LINES),or handls.Drawline().

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MartinLyne · Feb 06, 2015 at 09:45 PM 0

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Too often overlooked. Great for quick debugging in game view.

Answer 5

Answer by ericksson · Nov 27, 2009 at 08:59 AM

There is a discussion about this here: http://forum.unity3d.com/viewtopic.php?t=34735&sid=b7db7a2f8b373969ba16f82a6af23b4a

The script discussed above is here: http://www.unifycommunity.com/wiki/index.php?title=DrawLine

It might not work for complex drawing cases, but it might work for what you need.

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How to draw a line using script

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