Minimal build.zig for building bgfx, and using it in a Zig project.

build.zig

const std = @import("std");

pub fn build(b: *std.Build) !void {
    const target = b.standardTargetOptions(.{});
    const optimize = b.standardOptimizeOption(.{});

    const is_debug = optimize == .Debug;

    // BGFX
    // ----

    const bgfx = b.addStaticLibrary(.{
        .name = "bgfx",
        .target = target,
        .optimize = optimize,
    });
    bgfx.defineCMacro("BX_CONFIG_DEBUG", if (is_debug) "1" else "0");
    bgfx.linkSystemLibrary("c++");
    bgfx.addIncludePath(.{ .path = "dep/bx/include" });
    bgfx.addIncludePath(.{ .path = "dep/bx/3rdparty" });
    bgfx.addIncludePath(.{ .path = "dep/bgfx/include" });
    bgfx.addIncludePath(.{ .path = "dep/bimg/include" });
    bgfx.addIncludePath(.{ .path = "dep/bimg/3rdparty" });
    bgfx.addIncludePath(.{ .path = "dep/bimg/3rdparty/astc-encoder/include" });
    bgfx.addIncludePath(.{ .path = "dep/bimg/3rdparty/tinyexr/deps/miniz" });

    switch (target.getOsTag()) {
        .freebsd => bgfx.addIncludePath(.{ .path = "dep/bx/include/compat/freebsd" }),
        .linux => bgfx.addIncludePath(.{ .path = "dep/bx/include/compat/linux" }),
        .ios => bgfx.addIncludePath(.{ .path = "dep/bx/include/compat/ios" }),
        .macos => bgfx.addIncludePath(.{ .path = "dep/bx/include/compat/osx" }),
        .windows => switch (target.getAbi()) {
            .gnu => bgfx.addIncludePath(.{ .path = "dep/bx/include/compat/mingw" }),
            .msvc => bgfx.addIncludePath(.{ .path = "dep/bx/include/compat/msvc" }),
            else => {},
        },
        else => {},
    }

    bgfx.addCSourceFiles(.{
        .files = &[_][]const u8{
            "dep/bx/src/amalgamated.cpp",
            "dep/bgfx/src/amalgamated.cpp",
            "dep/bimg/src/image.cpp",
            "dep/bimg/src/image_gnf.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_averages_and_directions.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_block_sizes.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_color_quantize.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_color_unquantize.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_compress_symbolic.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_compute_variance.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_decompress_symbolic.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_diagnostic_trace.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_entry.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_find_best_partitioning.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_ideal_endpoints_and_weights.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_image.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_integer_sequence.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_mathlib_softfloat.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_mathlib.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_partition_tables.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_percentile_tables.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_pick_best_endpoint_format.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_quantization.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_symbolic_physical.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_weight_align.cpp",
            "dep/bimg/3rdparty/astc-encoder/source/astcenc_weight_quant_xfer_tables.cpp",
            "dep/bimg/3rdparty/tinyexr/deps/miniz/miniz.c",
        },
    });

    if (bgfx.target.isDarwin()) {
        bgfx.defineCMacro("BGFX_CONFIG_RENDERER_VULKAN", "0"); // until we have a vulkan driver
        bgfx.linkSystemLibrary("objc");
        bgfx.linkFramework("Foundation");
        bgfx.addCSourceFiles(.{
            .files = &[_][]const u8{
                "dep/bgfx/src/renderer_mtl.mm",
            },
        });
    }

    const bgfx_mod = b.addModule("bgfx", .{
        .source_file = .{ .path = "dep/bgfx/bindings/zig/bgfx.zig" },
    });

    // Main Target using BGFX
    // ----------------------

    const lib = b.addStaticLibrary(.{
        .name = "mylib",
        .root_source_file = .{ .path = "src/mylib/root.zig" },
        .target = target,
        .optimize = optimize,
    });
    lib.linkLibrary(bgfx);            // Link symbols
    lib.addModule("bgfx", bgfx_mod);  // Expose @import("bgfx")
    b.installArtifact(b)              // Produce zig-out/libmylib.a

    // Testing, etc ...
    // ...
}