Moving an InputField according to the TextMeshPro text

I'm trying to simulate a terminal.
I have a TextMesh Pro text field which display all the text (from top to bottom).
And I have an Input Field.
Initially it's at the top of the empty text field, and every time the user writes something, the text field fills up and the input field should move down a line.
All like a normal bash/cmd terminal.

But, I can't do that. Even if there is no line spacing, and they have the same font size, when I move down the input field for a while, the gap increases (or decreseas, tweaking with millimetric precision).

Is there a way to do it?

Thanks for the help ^^

 

TextMeshPro has a function called GetPreferredValues() that can tell you how much space the current text takes up. (You can specify either the width or the height in order to see what the other dimension should be within that constraint.)

 

GetPreferredValues returns the size of the TexMesh Pro rect, and in my case it has a fixed size.
To be more clear, here's a little image (great artist skills here)

https://imgur.com/cufCOBW

 

Uh...I've written a bunch of different UI components that resize to the amount of text content by using GetPreferredValues(), so I'm reasonably confident it's giving values based on the text, not the transform.

For instance, this component will resize its transform based on the amount of space needed for text in a specified object. It can be used directly on the same object as the text, or on a parent container.

Code (CSharp):

1. using UnityEngine;
2. using TMPro;
3.  
4. // Resizes this object based on the preferred size of a TMP Text
5. [ExecuteInEditMode]
6. public class TextSizer : MonoBehaviour
7. {
8.     public TextMeshProUGUI text;
9.     public Vector2 padding;
10.     public Vector2 maxSize = new Vector2(1000, float.PositiveInfinity);
11.     public Vector2 minSize;
12.  
13.     public enum Mode
14.     {
15.         None        = 0,
16.         Horizontal  = 0x1,
17.         Vertical    = 0x2,
18.         Both        = Horizontal | Vertical
19.     }
20.     public Mode controlAxes = Mode.Both;
21.  
22.     protected string lastText = null;
23.     protected Vector2 lastSize;
24.     protected bool forceRefresh = false;
25.  
26.     protected virtual float MinX { get {
27.             if ((controlAxes & Mode.Horizontal) != 0) return minSize.x;
28.             return GetComponent<RectTransform>().rect.width - padding.x;
29.         } }
30.     protected virtual float MinY { get {
31.             if ((controlAxes & Mode.Vertical) != 0) return minSize.y;
32.             return GetComponent<RectTransform>().rect.height - padding.y;
33.         } }
34.     protected virtual float MaxX { get {
35.             if ((controlAxes & Mode.Horizontal) != 0) return maxSize.x;
36.             return GetComponent<RectTransform>().rect.width - padding.x;
37.         } }
38.     protected virtual float MaxY { get {
39.             if ((controlAxes & Mode.Vertical) != 0) return maxSize.y;
40.             return GetComponent<RectTransform>().rect.height - padding.y;
41.         } }
42.  
43.     protected virtual void Update ()
44.     {
45.         RectTransform rt = GetComponent<RectTransform>();
46.         if (text != null && (text.text != lastText || lastSize != rt.rect.size || forceRefresh))
47.         {
48.             lastText = text.text;
49.             Vector2 preferredSize = text.GetPreferredValues(MaxX, MaxY);
50.             preferredSize.x = Mathf.Clamp(preferredSize.x, MinX, MaxX);
51.             preferredSize.y = Mathf.Clamp(preferredSize.y, MinY, MaxY);
52.             preferredSize += padding;
53.  
54.             if ((controlAxes & Mode.Horizontal) != 0)
55.             {
56.                 rt.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, preferredSize.x);
57.             }
58.             if ((controlAxes & Mode.Vertical) != 0)
59.             {
60.                 rt.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, preferredSize.y);
61.             }
62.             lastSize = rt.rect.size;
63.             forceRefresh = false;
64.         }
65.     }
66.  
67.     // Forces a size recalculation on next Update
68.     public virtual void Refresh()
69.     {
70.         forceRefresh = true;
71.     }
72. }

 

Maybe you're right. What am I saying, probably you're totally right. Thanks for teaching me and sharing me that code.

I discovered that it was because a scroll rect fault: it had child size vertical control, so the size of the text field was clamped to the max size of the scroll view. My bad. Now I solved it.

Thank you again for your time and your help ^^