Sprite.OverrideGeometry

Parameters

Description

Sets up new Sprite geometry.

Vertex positions are in Sprite.rect space meaning from Rect.zero to Rect.size. Pivot offset and transformation to unit space is done automatically.

The size of the triangle array must always be a multiple of 3. The vertices connected to the triangle can be shared by simply indexing into the same vertex.

Sprite UVs are calculated automatically by mapping the provided geometry onto the Sprite texture.

Additional resources: rect.

In the script example below the polygon shown in the Sprite Editor - Polygon Resizing is used. In this case the sprite has 8 sides. The right-most vertex is moved 50 pixels into the sprite. This is the third vertex.

// Obtain the vertices from the script and modify the position
// of one of them. Use OverrideGeometry() for this.
using UnityEngine;

public class ExampleClass : MonoBehaviour
{
    private SpriteRenderer spriteR;
    private Rect buttonPos1;
    private Rect buttonPos2;

    void Start()
    {
        spriteR = gameObject.GetComponent<SpriteRenderer>();
        // Create a blank Texture and Sprite to override later on.
        var texture2D = new Texture2D(64, 64);
        spriteR.sprite = Sprite.Create(texture2D, new Rect(0, 0, texture2D.width, texture2D.height), Vector2.zero, 100);

        buttonPos1 = new Rect(10.0f, 10.0f, 200.0f, 30.0f);
        buttonPos2 = new Rect(10.0f, 50.0f, 200.0f, 30.0f);
    }

    void OnGUI()
    {
        if (GUI.Button(buttonPos1, "Draw Debug"))
            DrawDebug();

        if (GUI.Button(buttonPos2, "Perform OverrideGeometry"))
            ChangeSprite();
    }

    // Show the sprite triangles
    void DrawDebug()
    {
        Sprite sprite = spriteR.sprite;

        ushort[]  t = sprite.triangles;
        Vector2[] v = sprite.vertices;
        int a, b, c;

        // draw the triangles using grabbed vertices
        for (int i = 0; i < t.Length; i = i + 3)
        {
            a = t[i];
            b = t[i + 1];
            c = t[i + 2];
            Debug.DrawLine(v[a], v[b], Color.white, 100.0f);
            Debug.DrawLine(v[b], v[c], Color.white, 100.0f);
            Debug.DrawLine(v[c], v[a], Color.white, 100.0f);
        }
    }

    // Edit the vertices obtained from the sprite.  Use OverrideGeometry to
    // submit the changes.
    void ChangeSprite()
    {
        Sprite o = spriteR.sprite;
        Vector2[] sv = o.vertices;

        for (int i = 0; i < sv.Length; i++)
        {
            sv[i].x = Mathf.Clamp(
                (o.vertices[i].x - o.bounds.center.x -
                    (o.textureRectOffset.x / o.texture.width) + o.bounds.extents.x) /
                (2.0f * o.bounds.extents.x) * o.rect.width,
                0.0f, o.rect.width);

            sv[i].y = Mathf.Clamp(
                (o.vertices[i].y - o.bounds.center.y -
                    (o.textureRectOffset.y / o.texture.height) + o.bounds.extents.y) /
                (2.0f * o.bounds.extents.y) * o.rect.height,
                0.0f, o.rect.height);

            // make a small change to the 3rd vertex
            if (i == 2)
                sv[i].x = sv[i].x - 50;
        }

        o.OverrideGeometry(sv, o.triangles);
    }
}