added camera options

src/camera.zig

···
 
 const Camera = @This();
 
+pub const Options = struct {
+    image_width: usize,
+    aspect_ratio: f32,
+};
+
 image_height: usize,
 image_width: usize,
 aspect_ratio: f32,
···
 
 image: zigimg.Image,
 
-pub fn init(allocator: std.mem.Allocator, image_width: usize, aspect_ratio: f32) !Camera {
+pub fn init(allocator: std.mem.Allocator, opts: Options) !Camera {
+    const image_width = opts.image_width;
+    const aspect_ratio = opts.aspect_ratio;
     const image_height = @as(usize, @intFromFloat(@as(f32, @floatFromInt(image_width)) / aspect_ratio));
     if (image_height < 1) return error.ImageWidthLessThanOne;
 

src/main.zig

···
     const s = spall.trace(@src(), "Raytracer", .{});
 
     // Raytracing part
-    var raytracer = try rayray.Raytracer.init(allocator, world);
+    var raytracer = try rayray.Raytracer.init(allocator, world, .{ .aspect_ratio = 16.0 / 9.0, .image_width = 400 });
     defer raytracer.deinit();
 
     const img = try raytracer.render();

src/rayray.zig

···
     camera: Camera,
     world: hittable.HittableList,
 
-    pub fn init(allocator: std.mem.Allocator, world: hittable.HittableList) !Self {
+    pub fn init(allocator: std.mem.Allocator, world: hittable.HittableList, camera_opts: Camera.Options) !Self {
         return .{
             .allocator = allocator,
-            .camera = try Camera.init(allocator, 400, 16.0 / 9.0),
+            .camera = try Camera.init(allocator, camera_opts),
             .world = world,
         };
     }