/Samples/AdvancedGameExample/Game.cs

using System.Collections.Generic;

using Delta.ContentSystem;

using Delta.ContentSystem.Rendering;

using Delta.Engine;

using Delta.Engine.Dynamic;

using Delta.PhysicsEngines;

using Delta.PhysicsEngines.VisualShapes;

using Delta.Rendering.Basics.Fonts;

using Delta.Rendering.Cameras;

using Delta.Rendering.Models;

using Delta.Utilities.Datatypes;

using Delta.InputSystem;



namespace AdvancedGameExample

{

	/// <summary>

	/// Game class, which is the entry point for this game. Manages all the game

	/// logic and displays everything. More complex games obviously have more

	/// classes and will do things in a more organized and structured matter.

	/// This example game is about a 3D Pyramid of boxes, which can be pushed

	/// around (via Mouse, Touch or other input devices) to collapse the Pyramid

	/// with 3D Physics.

	/// </summary>

	class Game : DynamicModule

	{

		#region Constants

		/// <summary>

		/// Size of the pyramid. Bullet is really slow for this test so only use

		/// 10 * 10 pyramid. Use 20 * 20 for Jitter (handles this much quicker),

		/// 50 * 50 or more is also certainly possible, but slower!

		/// </summary>

		private static readonly int PyramidSize =

			Settings.Modules.PhysicsModule == "Bullet"

				? 10

				: 20;



		/// <summary>

		/// Size of each box for the Pyramid.

		/// </summary>

		private const float BoxSize = 2.0f;

		#endregion



		#region Private

		/// <summary>

		/// Mesh for drawing the ground plane

		/// </summary>

		private Mesh plane =

			Mesh.CreateSegmentedPlane("GroundPlane", 75, 75, 5, true, Color.White,

				Content.Exists("Ground", ContentType.Image)

					? new MaterialData()

					{

						DiffuseMapName = "Ground",

					}

					: MaterialData.Default);



		/// <summary>

		/// And list of shapes to draw for the pyramid in the 3D scene.

		/// </summary>

		private readonly List<BaseVisualPhysicsShape> shapesToDraw =

			new List<BaseVisualPhysicsShape>();

		#endregion



		#region Constructor

		/// <summary>

		/// Constructor, do additional initialization code here if needed.

		/// </summary>

		public Game()

			: base("Advanced Game", typeof(Application))

		{

			// Unable to continue if we have no physics (warnings are already in log)

			if (Physics.Instance == null)

			{

				Application.Quit();

				return;

			}



			Physics.Instance.SetGroundPlane(true, 0.0f);

			// Useful for debugging:

			//Physics.DebugEnabled = true;

			// Increase gravity to be less moon-like (not perfect, just tweaking)

			Physics.Gravity = Physics.DefaultGravity * 10.0f;

			// Create a camera for the 3D world.

			new LookAtCamera(new Vector(10, -25, 25));

			// And finally setup the pyramid boxes

			SetupPyramid();



			// Setup a few commands for some interaction (pushing boxes and reseting)

			Input.Commands[Command.UIClick].Add(delegate(CommandTrigger command)

			{

				// Create a ray from the input position (mouse, touch, whatever)

				Ray ray = ScreenSpace.GetRayFromScreenPoint(command.Position);

				// And try to grab the box we hit

				PhysicsBody grabBody;

				Vector hitNormal;

				float fraction;

				if (Physics.FindRayCast(ray, false, out grabBody, out hitNormal,

					out fraction) &&

					grabBody != null)

				{

					// Activate that body and push it in the direction we are looking

					grabBody.ApplyLinearImpulse(ray.Direction / 3.0f);

				}

			});

			Input.Commands[Command.UIRightClick].Add(delegate

			{

				SetupPyramid();

			});

			Input.Commands[Command.QuitTest].Add(delegate

			{

				Application.Quit();

			});

		}

		#endregion



		#region SetupPyramid

		/// <summary>

		/// Setup the pyramid of physics boxes for this example game

		/// </summary>

		private void SetupPyramid()

		{

			// If we already had boxes, just restore them!

			if (shapesToDraw.Count > 0)

			{

				foreach (BaseVisualPhysicsShape shape in shapesToDraw)

				{

					if (shape.Body != null)

					{

						shape.Body.AngularVelocity = Vector.Zero;

						shape.Body.LinearVelocity = Vector.Zero;

						shape.Body.RotationMatrix = Matrix.Identity;

						shape.Body.Position = shape.Body.InitialPosition;

						shape.Body.Restitution = 0.0f;

						shape.Body.IsActive = true;

					}

				}

			}

			else

			{

				// Otherwise create a new pyramid

				for (int height = 0; height < PyramidSize; height++)

				{

					for (int width = height; width < PyramidSize; width++)

					{

						// Very slightly increase height at the upper levels. This will cause

						// the pyramid to collapse and bounce of the top parts in the

						// beginning while the rest stays solid :)

						VisualPhysicsBox box = new VisualPhysicsBox(

							new Vector((width - height * 0.5f) * BoxSize * 1.1f -

								BoxSize * 1.1f * PyramidSize / 2.0f + 1.1f, 0.0f,

								1.0f + height * BoxSize * 1.1f),

							BoxSize, BoxSize, BoxSize, Color.White,

							new MaterialData()

							{

								DiffuseMapName =

									Content.Exists("Box", ContentType.Image)

										? "Box"

										: "DeltaEngineLogo"

							});



						shapesToDraw.Add(box);



						if (box.Body != null)

						{

							box.Body.Restitution = 0.0f;

						}

					}

				}

			}

		}

		#endregion



		#region Run

		/// <summary>

		/// Run game loop, called every frame to do all game logic updating.

		/// </summary>

		public override void Run()

		{

			// Show FPS and a simple text message

			Font.DrawTopLeftInformation(

				"Fps: " + Time.Fps + "\n" +

				"Click to push a box. Right click or hold touch to reset the " +

				"Pyramid.");



			// Draw the boxes of the pyramid

			foreach (BaseVisualPhysicsShape shape in shapesToDraw)

			{

				shape.Draw();

			}



			// Draw the ground plane (a little below the physical ground to avoid

			// overlapping and boxes going slightly into the ground).

			Matrix groundTransform = Matrix.CreateTranslation(0.0f, 0.0f, -0.01f);

			plane.Draw(ref groundTransform);

		}

		#endregion

	}

}