/// <summary>
/// Fills the vertexUnit with the quad data.
/// </summary>
/// <param name="vertexUnit">The vertexUnit to fill with the quad data.</param>
/// <param name="index">The start index in the index buffer.</param>
public virtual void FillVertexUnit(Purple.Graphics.VertexUnit vertexUnit, int index)
{
if (dirty)
{
Vector2 right = QuadManager.Instance.RotateUnit(new Vector2(size.X * this.scale.X, 0), this.rotationZ);
Vector2 down = QuadManager.Instance.RotateUnit(new Vector2(0, size.Y * this.scale.Y), this.rotationZ);
Vector2 a = this.position;
Vector2 b = this.position + right;
Vector2 c = this.position + down;
Vector2 d = this.position + down + right;
RectangleF texCoords = new RectangleF(
texture.TextureCoordinates.Left + texture.TextureCoordinates.Width * textureRectangle.Left,
texture.TextureCoordinates.Top + texture.TextureCoordinates.Height * textureRectangle.Top,
texture.TextureCoordinates.Width * textureRectangle.Width,
texture.TextureCoordinates.Height * textureRectangle.Height);
QuadUtil.FillPosition(positionCache, a, b, c, d);
QuadUtil.FillColor(colorCache, Color.From((int)(alpha * 255 + 0.5f), 0xff, 0xff, 0xff));
QuadUtil.FillTexture(textureCache, texCoords);
dirty = false;
}
positionCache.CopyTo(vertexUnit[typeof(PositionStream2)].Data, index);
colorCache.CopyTo(vertexUnit[typeof(ColorStream)].Data, index);
textureCache.CopyTo(vertexUnit[typeof(TextureStream)].Data, index);
}
