decouple engine and scene

src/Engine.zig

@@ -1,3 +1,5 @@
+const Engine = @This();
+
 const std = @import("std");
 const Recti = @import("geometry/Recti.zig");
 const Matrix4f = @import("geometry/Matrix4f.zig");
@@ -20,7 +22,13 @@ const HashMap = std.HashMap;
 // 	render: fn () void,
 // 	update: fn (f32) void,
 // };
+current_scene: Scene,
 
+pub fn create(initial_scene: Scene) Engine {
+	return .{
+		.current_scene = initial_scene
+	};
+}
 
 fn errorCallback(err: c_int, desc_c: [*c]const u8) callconv(.C) void {
 	const desc: *const u8 = @ptrCast(desc_c);
@@ -28,7 +36,7 @@ fn errorCallback(err: c_int, desc_c: [*c]const u8) callconv(.C) void {
 }
 
 // export fn run(game: *const IGame) !void {
-pub fn run() !void {
+pub fn run(self: *Engine) !void {
 	
 	// in case of errors, set callback early!
 	// for some reason this returns an error function as well??
@@ -87,19 +95,17 @@ pub fn run() !void {
 	
 	const projection = Matrix4f.orthographic(0, @floatFromInt(width), @floatFromInt(height), 0, 0, 100);
 
-	var scene = Scene.new();
-	defer scene.destroy();
-	try scene.start();
-
 	// run the main loop
 	while (c.glfwWindowShouldClose(window) == 0) {
 		shaders.set_projection_matrix(&projection);
 		c.glClear(c.GL_COLOR_BUFFER_BIT | c.GL_DEPTH_BUFFER_BIT);
-		scene.draw();
+		self.current_scene.draw();
 		// game.render();
 		// game.update(1.0);
 
 		c.glfwSwapBuffers(window);
 		c.glfwPollEvents();
+
+		self.current_scene.update(0.0042);
 	}
 }

src/Scene.zig

@@ -11,7 +11,7 @@ const ArrayList = std.ArrayList;
 
 entities: ArrayList(Entity),
 
-pub fn new() Scene {
+pub fn create() Scene {
 	const e: ArrayList(Entity) = ArrayList(Entity).init(std.heap.page_allocator);
 	return .{
 		.entities = e

src/main.zig

@@ -1,10 +1,11 @@
 
 const std = @import("std");
-const engine = @import("engine.zig");
+const Engine = @import("Engine.zig");
+// const assets = @import("assets.zig");
+const scenes = @import("scenes.zig");
 
 pub fn main() !void {
-
-	// engine.preload
-
+	// engine.preload(assets.load);
+	var engine = Engine.create(try scenes.game());
 	try engine.run();
 }

src/scenes.zig

@@ -0,0 +1,13 @@
+const Scene = @import("Scene.zig");
+const Terrain = @import("Terrain.zig");
+
+
+
+pub fn game() !Scene {
+	var scene = Scene.create();
+	// first try is for allocating more memory in entities
+	// second try is for allocating terrain on the heap...
+	try scene.add(try Terrain.create());
+
+	return scene;
+}