const Vec2i = @import("geometry/Vec2i.zig");

pub const Recti = struct {
	x: i32,
	y: i32,
	w: i32,
	h: i32,
	a: Vec2i,
	b: Vec2i,

	pub fn from_xywh(x: i32, y: i32, w: i32, h: i32) Recti {
		return .{
			.x = x,
			.y = y,
			.w = w,
			.h = h,
			.a = Vec2i.new(x, y),
			.b = Vec2i.new(x + w, y + h),
		};
	}
};

pub const Matrix4f = struct {
	values: [16]f32 = identity,

	const SIZE: i8 = 4 * 4;
	const identity = from_values([16]f32 {
		1, 0, 0, 0,
		0, 1, 0, 0,
		0, 0, 1, 0,
		0, 0, 0, 1,
	});

	pub fn from_values(values: [16]f32) Matrix4f {
		return .{ .values = values };
	}

	pub fn orthographic(left: f32, right: f32, bottom: f32, top: f32, near: f32, far: f32) Matrix4f {
		var ortho = Matrix4f.identity;
		ortho.values[0 + 0 * 4] = 2.0 / (right - left);
		ortho.values[1 + 1 * 4] = 2.0 / (top - bottom);
		ortho.values[2 + 2 * 4] = 2.0 / (near - far);

		ortho.values[0 + 3 * 4] = (left + right) / (left - right);
		ortho.values[1 + 3 * 4] = (bottom + top) / (bottom - top);
		ortho.values[2 + 3 * 4] = (far + near) / (far - near);
		return ortho;
	}
};