gaemstone/src/gaemstone.Client/Components/RenderingComponents.cs

using System.Drawing;
using System.Numerics;
using gaemstone.ECS;
using Silk.NET.OpenGL;

namespace gaemstone.Client.Components;

[Module]
public class RenderingComponents
{
	[Symbol, Component]
	public readonly struct MeshHandle
	{
		public uint Handle { get; }
		public int Count { get; }
		public bool IsIndexed { get; }

		public MeshHandle(uint handle, int count, bool indexed = true)
			{ Handle = handle; Count = count; IsIndexed = indexed; }
	}

	[Symbol, Component]
	public readonly struct TextureHandle
	{
		public TextureTarget Target { get; }
		public uint Handle { get; }

		public TextureHandle(TextureTarget target, uint handle)
			=> (Target, Handle) = (target, handle);
	}

	[Symbol, Component]
	public readonly struct TextureCoords4
	{
		public Vector2 TopLeft { get; }
		public Vector2 TopRight { get; }
		public Vector2 BottomLeft { get; }
		public Vector2 BottomRight { get; }

		public TextureCoords4(float x1, float y1, float x2, float y2)
		{
			TopLeft     = new(x1, y1);
			TopRight    = new(x2, y1);
			BottomLeft  = new(x1, y2);
			BottomRight = new(x2, y2);
		}

		public static TextureCoords4 FromIntCoords(Size textureSize, Point origin, Size size)
			=> FromIntCoords(textureSize, origin.X, origin.Y, size.Width, size.Height);
		public static TextureCoords4 FromIntCoords(Size textureSize, int x, int y, int width, int height) => new(
			x / (float)textureSize.Width + 0.001f,
			y / (float)textureSize.Height + 0.001f,
			(x + width) / (float)textureSize.Width - 0.001f,
			(y + height) / (float)textureSize.Height - 0.001f);

		public static TextureCoords4 FromGrid(int numCellsX, int numCellsY, int cellX, int cellY) => new(
			cellX / (float)numCellsX + 0.001f,
			cellY / (float)numCellsY + 0.001f,
			(cellX + 1) / (float)numCellsX - 0.001f,
			(cellY + 1) / (float)numCellsY - 0.001f);
	}
}