feat: update zig to 0.16.0HEADmain

4 files changed, 121 insertions, 87 deletions

diff --git a/.gitignore b/.gitignore
index d48bc97..dbdcba7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 /.zig-cache
 /zig-out
+/zig-pkg
 /out.png
diff --git a/build.zig b/build.zig
index 137afcb..cc59e98 100644
--- a/build.zig
+++ b/build.zig
@@ -1,68 +1,86 @@
 const std = @import("std");
 
-// Although this function looks imperative, note that its job is to
-// declaratively construct a build graph that will be executed by an external
-// runner.
+// Although this function looks imperative, it does not perform the build
+// directly and instead it mutates the build graph (`b`) that will be then
+// executed by an external runner. The functions in `std.Build` implement a DSL
+// for defining build steps and express dependencies between them, allowing the
+// build runner to parallelize the build automatically (and the cache system to
+// know when a step doesn't need to be re-run).
 pub fn build(b: *std.Build) void {
-    // Standard target options allows the person running `zig build` to choose
+    // Standard target options allow the person running `zig build` to choose
     // what target to build for. Here we do not override the defaults, which
     // means any target is allowed, and the default is native. Other options
     // for restricting supported target set are available.
     const target = b.standardTargetOptions(.{});
-
     // Standard optimization options allow the person running `zig build` to select
     // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
     // set a preferred release mode, allowing the user to decide how to optimize.
     const optimize = b.standardOptimizeOption(.{});
+    // It's also possible to define more custom flags to toggle optional features
+    // of this build script using `b.option()`. All defined flags (including
+    // target and optimize options) will be listed when running `zig build --help`
+    // in this directory.
 
-    // This creates a "module", which represents a collection of source files alongside
+    // This creates a module, which represents a collection of source files alongside
     // some compilation options, such as optimization mode and linked system libraries.
-    // Every executable or library we compile will be based on one or more modules.
-    const lib_mod = b.createModule(.{
-        // `root_source_file` is the Zig "entry point" of the module. If a module
-        // only contains e.g. external object files, you can make this `null`.
-        // In this case the main source file is merely a path, however, in more
-        // complicated build scripts, this could be a generated file.
+    // Zig modules are the preferred way of making Zig code available to consumers.
+    // addModule defines a module that we intend to make available for importing
+    // to our consumers. We must give it a name because a Zig package can expose
+    // multiple modules and consumers will need to be able to specify which
+    // module they want to access.
+    const mod = b.addModule("RayTracingInOneWeekend", .{
+        // The root source file is the "entry point" of this module. Users of
+        // this module will only be able to access public declarations contained
+        // in this file, which means that if you have declarations that you
+        // intend to expose to consumers that were defined in other files part
+        // of this module, you will have to make sure to re-export them from
+        // the root file.
         .root_source_file = b.path("src/root.zig"),
+        // Later on we'll use this module as the root module of a test executable
+        // which requires us to specify a target.
         .target = target,
-        .optimize = optimize,
-    });
-
-    // We will also create a module for our other entry point, 'main.zig'.
-    const exe_mod = b.createModule(.{
-        // `root_source_file` is the Zig "entry point" of the module. If a module
-        // only contains e.g. external object files, you can make this `null`.
-        // In this case the main source file is merely a path, however, in more
-        // complicated build scripts, this could be a generated file.
-        .root_source_file = b.path("src/main.zig"),
-        .target = target,
-        .optimize = optimize,
-    });
-
-    // Modules can depend on one another using the `std.Build.Module.addImport` function.
-    // This is what allows Zig source code to use `@import("foo")` where 'foo' is not a
-    // file path. In this case, we set up `exe_mod` to import `lib_mod`.
-    exe_mod.addImport("zig_init_lib", lib_mod);
-
-    // Now, we will create a static library based on the module we created above.
-    // This creates a `std.Build.Step.Compile`, which is the build step responsible
-    // for actually invoking the compiler.
-    const lib = b.addLibrary(.{
-        .linkage = .static,
-        .name = "zig_init",
-        .root_module = lib_mod,
     });
 
-    // This declares intent for the library to be installed into the standard
-    // location when the user invokes the "install" step (the default step when
-    // running `zig build`).
-    b.installArtifact(lib);
-
-    // This creates another `std.Build.Step.Compile`, but this one builds an executable
-    // rather than a static library.
+    // Here we define an executable. An executable needs to have a root module
+    // which needs to expose a `main` function. While we could add a main function
+    // to the module defined above, it's sometimes preferable to split business
+    // logic and the CLI into two separate modules.
+    //
+    // If your goal is to create a Zig library for others to use, consider if
+    // it might benefit from also exposing a CLI tool. A parser library for a
+    // data serialization format could also bundle a CLI syntax checker, for example.
+    //
+    // If instead your goal is to create an executable, consider if users might
+    // be interested in also being able to embed the core functionality of your
+    // program in their own executable in order to avoid the overhead involved in
+    // subprocessing your CLI tool.
+    //
+    // If neither case applies to you, feel free to delete the declaration you
+    // don't need and to put everything under a single module.
     const exe = b.addExecutable(.{
         .name = "RayTracingInOneWeekend",
-        .root_module = exe_mod,
+        .root_module = b.createModule(.{
+            // b.createModule defines a new module just like b.addModule but,
+            // unlike b.addModule, it does not expose the module to consumers of
+            // this package, which is why in this case we don't have to give it a name.
+            .root_source_file = b.path("src/main.zig"),
+            // Target and optimization levels must be explicitly wired in when
+            // defining an executable or library (in the root module), and you
+            // can also hardcode a specific target for an executable or library
+            // definition if desireable (e.g. firmware for embedded devices).
+            .target = target,
+            .optimize = optimize,
+            // List of modules available for import in source files part of the
+            // root module.
+            .imports = &.{
+                // Here "zig_init" is the name you will use in your source code to
+                // import this module (e.g. `@import("zig_init")`). The name is
+                // repeated because you are allowed to rename your imports, which
+                // can be extremely useful in case of collisions (which can happen
+                // importing modules from different packages).
+                .{ .name = "RayTracingInOneWeekend", .module = mod },
+            },
+        }),
     });
 
     const zigimg_dependency = b.dependency("zigimg", .{
@@ -73,19 +91,29 @@ pub fn build(b: *std.Build) void {
     exe.root_module.addImport("zigimg", zigimg_dependency.module("zigimg"));
 
     // This declares intent for the executable to be installed into the
-    // standard location when the user invokes the "install" step (the default
-    // step when running `zig build`).
+    // install prefix when running `zig build` (i.e. when executing the default
+    // step). By default the install prefix is `zig-out/` but can be overridden
+    // by passing `--prefix` or `-p`.
     b.installArtifact(exe);
 
-    // This *creates* a Run step in the build graph, to be executed when another
-    // step is evaluated that depends on it. The next line below will establish
-    // such a dependency.
+    // This creates a top level step. Top level steps have a name and can be
+    // invoked by name when running `zig build` (e.g. `zig build run`).
+    // This will evaluate the `run` step rather than the default step.
+    // For a top level step to actually do something, it must depend on other
+    // steps (e.g. a Run step, as we will see in a moment).
+    const run_step = b.step("run", "Run the app");
+
+    // This creates a RunArtifact step in the build graph. A RunArtifact step
+    // invokes an executable compiled by Zig. Steps will only be executed by the
+    // runner if invoked directly by the user (in the case of top level steps)
+    // or if another step depends on it, so it's up to you to define when and
+    // how this Run step will be executed. In our case we want to run it when
+    // the user runs `zig build run`, so we create a dependency link.
     const run_cmd = b.addRunArtifact(exe);
+    run_step.dependOn(&run_cmd.step);
 
-    // By making the run step depend on the install step, it will be run from the
+    // By making the run step depend on the default step, it will be run from the
     // installation directory rather than directly from within the cache directory.
-    // This is not necessary, however, if the application depends on other installed
-    // files, this ensures they will be present and in the expected location.
     run_cmd.step.dependOn(b.getInstallStep());
 
     // This allows the user to pass arguments to the application in the build
@@ -94,30 +122,42 @@ pub fn build(b: *std.Build) void {
         run_cmd.addArgs(args);
     }
 
-    // This creates a build step. It will be visible in the `zig build --help` menu,
-    // and can be selected like this: `zig build run`
-    // This will evaluate the `run` step rather than the default, which is "install".
-    const run_step = b.step("run", "Run the app");
-    run_step.dependOn(&run_cmd.step);
-
-    // Creates a step for unit testing. This only builds the test executable
-    // but does not run it.
-    const lib_unit_tests = b.addTest(.{
-        .root_module = lib_mod,
+    // Creates an executable that will run `test` blocks from the provided module.
+    // Here `mod` needs to define a target, which is why earlier we made sure to
+    // set the releative field.
+    const mod_tests = b.addTest(.{
+        .root_module = mod,
     });
 
-    const run_lib_unit_tests = b.addRunArtifact(lib_unit_tests);
+    // A run step that will run the test executable.
+    const run_mod_tests = b.addRunArtifact(mod_tests);
 
-    const exe_unit_tests = b.addTest(.{
-        .root_module = exe_mod,
+    // Creates an executable that will run `test` blocks from the executable's
+    // root module. Note that test executables only test one module at a time,
+    // hence why we have to create two separate ones.
+    const exe_tests = b.addTest(.{
+        .root_module = exe.root_module,
     });
 
-    const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests);
+    // A run step that will run the second test executable.
+    const run_exe_tests = b.addRunArtifact(exe_tests);
+
+    // A top level step for running all tests. dependOn can be called multiple
+    // times and since the two run steps do not depend on one another, this will
+    // make the two of them run in parallel.
+    const test_step = b.step("test", "Run tests");
+    test_step.dependOn(&run_mod_tests.step);
+    test_step.dependOn(&run_exe_tests.step);
 
-    // Similar to creating the run step earlier, this exposes a `test` step to
-    // the `zig build --help` menu, providing a way for the user to request
-    // running the unit tests.
-    const test_step = b.step("test", "Run unit tests");
-    test_step.dependOn(&run_lib_unit_tests.step);
-    test_step.dependOn(&run_exe_unit_tests.step);
+    // Just like flags, top level steps are also listed in the `--help` menu.
+    //
+    // The Zig build system is entirely implemented in userland, which means
+    // that it cannot hook into private compiler APIs. All compilation work
+    // orchestrated by the build system will result in other Zig compiler
+    // subcommands being invoked with the right flags defined. You can observe
+    // these invocations when one fails (or you pass a flag to increase
+    // verbosity) to validate assumptions and diagnose problems.
+    //
+    // Lastly, the Zig build system is relatively simple and self-contained,
+    // and reading its source code will allow you to master it.
 }
diff --git a/build.zig.zon b/build.zig.zon
index 415faee..bb93711 100644
--- a/build.zig.zon
+++ b/build.zig.zon
@@ -7,11 +7,9 @@
     // It is redundant to include "zig" in this name because it is already
     // within the Zig package namespace.
     .name = .RayTracingInOneWeekend,
-
     // This is a [Semantic Version](https://semver.org/).
     // In a future version of Zig it will be used for package deduplication.
     .version = "0.2.0",
-
     // Together with name, this represents a globally unique package
     // identifier. This field is generated by the Zig toolchain when the
     // package is first created, and then *never changes*. This allows
@@ -25,11 +23,9 @@
     // on the following line intact, so that it shows up in code reviews that
     // modify the field.
     .fingerprint = 0x81e32b5abe329337, // Changing this has security and trust implications.
-
     // Tracks the earliest Zig version that the package considers to be a
     // supported use case.
-    .minimum_zig_version = "0.14.0",
-
+    .minimum_zig_version = "0.16.0",
     // This field is optional.
     // Each dependency must either provide a `url` and `hash`, or a `path`.
     // `zig build --fetch` can be used to fetch all dependencies of a package, recursively.
@@ -66,11 +62,10 @@
         //    .lazy = false,
         //},
         .zigimg = .{
-            .url = "git+https://github.com/zigimg/zigimg.git#362cdd6bce109f7bc674be134cddd378f52da5d4",
-            .hash = "zigimg-0.1.0-8_eo2jNrFQD4mu3EAUkfQRmCkyfprdIXc8JQ6uyxhjSQ",
+            .url = "git+https://github.com/zigimg/zigimg.git#c7e81a13bff1cf4c5b7f085a8360f9d551143d40",
+            .hash = "zigimg-0.1.0-8_eo2uScFwCnpzB1Y2n_jf3euDfMEeCLxJE_E5_W5BNe",
         },
     },
-
     // Specifies the set of files and directories that are included in this package.
     // Only files and directories listed here are included in the `hash` that
     // is computed for this package. Only files listed here will remain on disk
diff --git a/src/main.zig b/src/main.zig
index 060c6ee..9783ca3 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -292,10 +292,8 @@ fn generateCornellBox(allocator: anytype) !Hittable {
     return .{ .list = .{ .objects = hittable_objects } };
 }
 
-pub fn main() !void {
-    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
-    const allocator = gpa.allocator();
-    defer std.debug.assert(gpa.deinit() == .ok);
+pub fn main(init: std.process.Init) !void {
+    const allocator = init.gpa;
 
     var rng_ = std.Random.DefaultPrng.init(42);
     const rng = rng_.random();
@@ -403,5 +401,5 @@ pub fn main() !void {
 
     // Output
     var write_buf: [zigimg.io.DEFAULT_BUFFER_SIZE]u8 = undefined;
-    try image.writeToFilePath(allocator, "out.png", write_buf[0..], .{ .png = .{} });
+    try image.writeToFilePath(allocator, init.io, "out.png", write_buf[0..], .{ .png = .{} });
 }