How to render a sprite to a quad?

Questions & Answers
1

I select a sprite to render on a quad. I use the following code:

public Sprite       m_sprite;

void Awake()
{
    m_renderer  = GetComponent< MeshRenderer >();
    m_mesh      = GetComponent< MeshFilter >().mesh;
    m_material  = m_renderer.material;

    Rect spriteRect = m_sprite.textureRect;

    spriteRect.x /= m_sprite.texture.width;
    spriteRect.width /= m_sprite.texture.width;
    spriteRect.y /= m_sprite.texture.height;
    spriteRect.height /= m_sprite.texture.height;

    // Log.Info("spriteRect {0} num UVs {1}", spriteRect, m_mesh.uv.Length);

    // m_mesh.uv[0] = new Vector2(spriteRect.x + 0.0f,             spriteRect.y + spriteRect.height);
    // m_mesh.uv[1] = new Vector2(spriteRect.x + spriteRect.width, spriteRect.y + spriteRect.height);
    // m_mesh.uv[2] = new Vector2(spriteRect.x + 0.0f,             spriteRect.y + 0.0f);
    // m_mesh.uv[3] = new Vector2(spriteRect.x + spriteRect.width, spriteRect.y + 0.0f);

    m_mesh.uv[0] = new Vector2(0.0f, 1.0f);
    m_mesh.uv[1] = new Vector2(1.0f, 1.0f);
    m_mesh.uv[2] = new Vector2(0.0f, 0.0f);
    m_mesh.uv[3] = new Vector2(1.0f, 0.0f);

    m_material.mainTexture = m_sprite.texture;
}

MeshRenderer        m_renderer;
Mesh                m_mesh;
Material            m_material;

Update 1: as stevethorne pointed out I need the UVs but the texture is scramble even with the default UVs in the code above. Why is that does the shader or material need certain UVs?

2

I believe that reading from mesh.uv gives you a copy of the array, not a reference to the array, so you need to do it this way:

Vector2[] uvs = m_mesh.uv;
uvs[0] = new Vector2(0.0f, 1.0f);
uvs[1] = new Vector2(1.0f, 1.0f);
uvs[2] = new Vector2(0.0f, 0.0f);
uvs[3] = new Vector2(1.0f, 0.0f);
m_mesh.uv = uvs;

Why is that does the shader or
material need certain UVs?

The uvs tell the shader what part of the texture to render for each triangle.

At first glance, it appears that your commented out calculations for uvs should work.