Question by jintaenate · Jan 02, 2021 at 10:29 AM · ui calculate

How to draw line smooth in unity (c# base coding problem)

I want to draw line from unityUI. (i dont want to use Line Renderer in unity).

So I figured out the coding below, but my problem is the line sizes are not constant.

Blockquote

 public class MyUILineRenderer : Graphic
 {
 public Vector2[] pointPos;
 public float[] angles;
 public MyUIGridRenderer gridRenderer;

 public Vector2Int gridSize = new Vector2Int(1, 1);
 public float lineThickness = 0.5f;
 public float width;
 public float height;
 public float unitWidth;
 public float unitHeight;

 public float angleHelp;
 public bool calAngle;

 public Color[] colors;

 protected override void OnPopulateMesh(VertexHelper vh)
 {
     vh.Clear();
     width = rectTransform.rect.width;
     height = rectTransform.rect.height;

     unitWidth = width / (float)gridSize.x;
     unitHeight = height / (float)gridSize.y;
     if (calAngle)
     {
         angles = new float[pointPos.Length];
     }

     if (pointPos.Length < 2)
     {
         return;
     }

     float angle = 0;

     for (int i = 0; i < pointPos.Length; i++)
     {
         Vector2 point = pointPos[i];

         if (i < pointPos.Length - 1)
         {
             if (calAngle)
             {
                 angle = angles[i] = -GetAngle(pointPos[i], pointPos[i + 1]) + angleHelp;
             }
             else
             {
                 angle = angles[i];
             }
         }
         DrawLine(vh, point, angle);
     }

     int count = pointPos.Length * 2 - 2;
     for (int i = 0; i < count; i += 2)
     {
         vh.AddTriangle(i + 0, i + 1, i + 3);
         vh.AddTriangle(i + 0, i + 2, i + 3);
     }
 }

 public float GetAngle(Vector2 currentPos, Vector2 targetPos) {
     return (float)(Mathf.Atan2(targetPos.y - currentPos.y, targetPos.x - currentPos.x) * (180 / Mathf.PI));
 }

 private void DrawLine(VertexHelper vh, Vector2 point, float angle)
 {
     UIVertex vertex = UIVertex.simpleVert;
     vertex.color = colors[0];

     vertex.position = Quaternion.Euler(0, 0, angle) * new Vector3(-lineThickness, 0);
     vertex.position += new Vector3(unitWidth * point.x, unitHeight * point.y);
     vh.AddVert(vertex);

     vertex.color = colors[1];
     vertex.position = Quaternion.Euler(0, 0, angle) * new Vector3(lineThickness, 0);
     vertex.position += new Vector3(unitWidth * point.x, unitHeight * point.y);
     vh.AddVert(vertex);
 }
 }

and when i draw in unity like this

alt text