110 lines
3.5 KiB
C#

using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Syntriax.Engine.Core;
namespace Syntriax.Engine.Integration.MonoGame;
public class MonoGameCamera2DBehaviour : BehaviourBase, ICamera2D, IFirstFrameUpdate, IPreDraw
{
public event MatrixTransformChangedArguments? OnMatrixTransformChanged = null;
public event ViewportChangedArguments? OnViewportChanged = null;
public event ZoomChangedArguments? OnZoomChanged = null;
private Matrix _matrixTransform = Matrix.Identity;
private Viewport _viewport = default;
private float _zoom = 1f;
public GraphicsDeviceManager Graphics { get; private set; } = null!;
public ITransform2D Transform { get; private set; } = null!;
public Matrix MatrixTransform
{
get => _matrixTransform;
set
{
if (_matrixTransform == value)
return;
_matrixTransform = value;
OnMatrixTransformChanged?.Invoke(this);
}
}
public Vector2D Position
{
get => Transform.Position;
set => Transform.Position = value;
}
public Viewport Viewport
{
get => _viewport;
set
{
if (_viewport.Equals(value))
return;
_viewport = value;
OnViewportChanged?.Invoke(this);
}
}
public float Zoom
{
get => _zoom;
set
{
float newValue = Syntriax.Engine.Core.Math.Max(0.1f, value);
if (_zoom == newValue)
return;
_zoom = newValue;
OnZoomChanged?.Invoke(this);
}
}
public float Rotation
{
get => Transform.Rotation;
set => Transform.Rotation = value;
}
// TODO This causes delay since OnPreDraw calls assuming this is called in in Update
public Vector2D ScreenToWorldPosition(Vector2D screenPosition)
{
Vector2D worldPosition = Vector2.Transform(screenPosition.ToVector2(), Matrix.Invert(MatrixTransform)).ToVector2D();
return worldPosition.Scale(EngineConverterExtensions.screenScale);
}
public Vector2D WorldToScreenPosition(Vector2D worldPosition)
{
Vector2D screenPosition = Vector2.Transform(worldPosition.ToVector2(), MatrixTransform).ToVector2D();
return screenPosition.Scale(EngineConverterExtensions.screenScale);
}
public void FirstActiveFrame()
{
Graphics = BehaviourController.UniverseObject.Universe.FindRequiredBehaviour<MonoGameWindowContainer>().Window.Graphics;
Viewport = Graphics.GraphicsDevice.Viewport;
}
public void PreDraw()
{
MatrixTransform =
Matrix.CreateTranslation(new Vector3(-Position.X, Position.Y, 0f)) *
Matrix.CreateRotationZ(Rotation * Syntriax.Engine.Core.Math.DegreeToRadian) *
Matrix.CreateScale(Transform.Scale.X.Max(Transform.Scale.Y)) *
Matrix.CreateScale(Zoom) *
Matrix.CreateTranslation(new Vector3(_viewport.Width * .5f, _viewport.Height * .5f, 0f));
}
protected sealed override void InitializeInternal() => Transform = BehaviourController.GetRequiredBehaviour<ITransform2D>();
protected sealed override void FinalizeInternal() => Transform = null!;
public delegate void MatrixTransformChangedArguments(MonoGameCamera2DBehaviour sender);
public delegate void ViewportChangedArguments(MonoGameCamera2DBehaviour sender);
public delegate void ZoomChangedArguments(MonoGameCamera2DBehaviour sender);
}