[examples] automatically rebuild raylib

Hooked up raylib as a library in the examples build so that if a change
is made in raylib then running `zig build` in the examples directory
will automatically rebuild raylib.

The main pieces to this are the build.zig.zon file which allows the
examples build to see the parent raylib directory.  Then we can add
raylib as a typical dependency and grab the "raylib" artifact to link
to. We also no longer need to add include paths since raylib's build.zig
installs them for us.

examples/build.zig

@@ -2,13 +2,19 @@ const std = @import("std");
 const builtin = @import("builtin");
 
 // This has been tested to work with zig 0.12.0
-fn add_module(comptime module: []const u8, b: *std.Build, target: std.Build.ResolvedTarget, optimize: std.builtin.OptimizeMode) !*std.Build.Step {
+fn add_module(
+    comptime module: []const u8,
+    b: *std.Build,
+    target: std.Build.ResolvedTarget,
+    optimize: std.builtin.OptimizeMode,
+    raylib: *std.Build.Step.Compile,
+) !*std.Build.Step {
     if (target.result.os.tag == .emscripten) {
         @panic("Emscripten building via Zig unsupported");
     }
 
     const all = b.step(module, "All " ++ module ++ " examples");
-    var dir = try std.fs.cwd().openDir(module, .{ .iterate = true });
+    var dir = try std.fs.cwd().openDir(b.pathFromRoot(module), .{ .iterate = true });
     defer if (comptime builtin.zig_version.minor >= 12) dir.close();
 
     var iter = dir.iterate();
@@ -28,17 +34,7 @@ fn add_module(comptime module: []const u8, b: *std.Build, target: std.Build.Reso
         });
         exe.addCSourceFile(.{ .file = b.path(path), .flags = &.{} });
         exe.linkLibC();
-        exe.addObjectFile(switch (target.result.os.tag) {
-            .windows => b.path("../zig-out/lib/raylib.lib"),
-            .linux => b.path("../zig-out/lib/libraylib.a"),
-            .macos => b.path("../zig-out/lib/libraylib.a"),
-            .emscripten => b.path("../zig-out/lib/libraylib.a"),
-            else => @panic("Unsupported OS"),
-        });
-
-        exe.addIncludePath(b.path("../src"));
-        exe.addIncludePath(b.path("../src/external"));
-        exe.addIncludePath(b.path("../src/external/glfw/include"));
+        exe.linkLibrary(raylib);
 
         switch (target.result.os.tag) {
             .windows => {
@@ -97,14 +93,20 @@ pub fn build(b: *std.Build) !void {
     // set a preferred release mode, allowing the user to decide how to optimize.
     const optimize = b.standardOptimizeOption(.{});
 
+    const raylib_dep = b.dependency("raylib", .{
+        .target = target,
+        .optimize = optimize,
+    });
+    const raylib = raylib_dep.artifact("raylib");
+
     const all = b.getInstallStep();
 
-    all.dependOn(try add_module("audio", b, target, optimize));
-    all.dependOn(try add_module("core", b, target, optimize));
-    all.dependOn(try add_module("models", b, target, optimize));
-    all.dependOn(try add_module("others", b, target, optimize));
-    all.dependOn(try add_module("shaders", b, target, optimize));
-    all.dependOn(try add_module("shapes", b, target, optimize));
-    all.dependOn(try add_module("text", b, target, optimize));
-    all.dependOn(try add_module("textures", b, target, optimize));
+    all.dependOn(try add_module("audio", b, target, optimize, raylib));
+    all.dependOn(try add_module("core", b, target, optimize, raylib));
+    all.dependOn(try add_module("models", b, target, optimize, raylib));
+    all.dependOn(try add_module("others", b, target, optimize, raylib));
+    all.dependOn(try add_module("shaders", b, target, optimize, raylib));
+    all.dependOn(try add_module("shapes", b, target, optimize, raylib));
+    all.dependOn(try add_module("text", b, target, optimize, raylib));
+    all.dependOn(try add_module("textures", b, target, optimize, raylib));
 }

examples/build.zig.zon

@@ -0,0 +1,10 @@
+.{
+    .name = .raylib_examples,
+    .version = "0.0.0",
+    .fingerprint = 0x3570d11b06c2907a, // Changing this has security and trust implications.
+    .minimum_zig_version = "0.14.0",
+    .dependencies = .{
+        .raylib = .{ .path = ".." },
+    },
+    .paths = .{"."},
+}