Shader compilation utility

build.zig

@@ -1,56 +1,48 @@
 const std = @import("std");
 const vkgen = @import("generator/index.zig");
+const Step = std.build.Step;
 const Builder = std.build.Builder;
 const path = std.fs.path;
 
-const Resources = struct {
+pub const ResourceGenStep = struct {
+    step: Step,
+    shader_step: *vkgen.ShaderCompileStep,
     builder: *Builder,
-    wfs: *std.build.WriteFileStep,
-    data: std.ArrayList(u8),
+    full_out_path: []const u8,
+    resources: std.ArrayList(u8),
 
-    fn init(builder: *Builder) *Resources {
-        const res = builder.allocator.create(Resources) catch unreachable;
-        res.* = .{
+    pub fn init(builder: *Builder, out: []const u8) *ResourceGenStep {
+        const self = builder.allocator.create(ResourceGenStep) catch unreachable;
+        self.* = .{
+            .step = Step.init(.Custom, "resources", builder.allocator, make),
+            .shader_step = vkgen.ShaderCompileStep.init(builder, "glslc"),
             .builder = builder,
-            .wfs = builder.addWriteFiles(),
-            .data = std.ArrayList(u8).init(builder.allocator),
+            .full_out_path = path.join(builder.allocator, &[_][]const u8{
+                self.builder.build_root,
+                builder.cache_root,
+                out,
+            }) catch unreachable,
+            .resources = std.ArrayList(u8).init(builder.allocator),
         };
-        return res;
+
+        self.step.dependOn(&self.shader_step.step);
+        return self;
     }
 
-    fn addShader(self: *Resources, shader: []const u8) void {
-        const spv_name = std.mem.join(
-            self.builder.allocator,
-            "",
-            &[_][]const u8{shader, ".spv"},
+    pub fn addShader(self: *ResourceGenStep, name: []const u8, source: []const u8) void {
+        self.resources.writer().print(
+            "pub const {} = @embedFile(\"{}\");\n",
+            .{name, self.shader_step.add("examples/shaders/test.frag")}
         ) catch unreachable;
-        const dst = path.join(
-            self.builder.allocator,
-            &[_][]const u8{self.builder.cache_root, "test.frag.spv"}
-        ) catch unreachable;
-
-        const src = path.join(
-            self.builder.allocator,
-            &[_][]const u8{self.builder.build_root, shader}
-        ) catch unreachable;
-
-        const compile_step = self.builder.addSystemCommand(&[_][]const u8{
-            "glslc",
-            "--target-env=vulkan1.2",
-            src,
-            "-o",
-            dst
-        });
-
-        self.wfs.step.dependOn(&compile_step.step);
-
-        const writer = self.data.writer();
-        writer.print("const @\"{}\" = @embedFile(\"{}\");", .{src, dst}) catch unreachable;
     }
 
-    fn finalize(self: *Resources) *std.build.WriteFileStep {
-        self.wfs.add("resources.zig", self.data.toOwnedSlice());
-        return self.wfs;
+    fn make(step: *Step) !void {
+        const self = @fieldParentPtr(ResourceGenStep, "step", step);
+        const cwd = std.fs.cwd();
+
+        const dir = path.dirname(self.full_out_path).?;
+        try cwd.makePath(dir);
+        try cwd.writeFile(self.full_out_path, self.resources.items);
     }
 };
 
@@ -58,10 +50,6 @@ pub fn build(b: *Builder) void {
     var test_step = b.step("test", "Run all the tests");
     test_step.dependOn(&b.addTest("generator/index.zig").step);
 
-    const res = Resources.init(b);
-    res.addShader("examples/shaders/test.frag");
-    const wfs = res.finalize();
-
     const target = b.standardTargetOptions(.{});
     const mode = b.standardReleaseOptions();
     const example_exe = b.addExecutable("example", "examples/main.zig");
@@ -70,11 +58,15 @@ pub fn build(b: *Builder) void {
     example_exe.install();
     example_exe.linkSystemLibrary("c");
     example_exe.linkSystemLibrary("glfw");
-    example_exe.step.dependOn(&wfs.step);
 
-    const gen_step = vkgen.VkGenerateStep.init(b, "examples/vk.xml", "vk.zig");
-    example_exe.step.dependOn(&gen_step.step);
-    example_exe.addPackagePath("vulkan", gen_step.full_out_path);
+    const gen = vkgen.VkGenerateStep.init(b, "examples/vk.xml", "vk.zig");
+    example_exe.step.dependOn(&gen.step);
+    example_exe.addPackagePath("vulkan", gen.full_out_path);
+
+    const res = ResourceGenStep.init(b, "resources.zig");
+    res.addShader("test_frag", "examples/shaders/test.frag");
+    example_exe.step.dependOn(&res.step);
+    example_exe.addPackagePath("resources", res.full_out_path);
 
     const example_run_cmd = example_exe.run();
     example_run_cmd.step.dependOn(b.getInstallStep());

examples/main.zig

@@ -1,6 +1,7 @@
 const std = @import("std");
 const vk = @import("vulkan");
 const c = @import("c.zig");
+const resources = @import("resources");
 const GraphicsContext = @import("graphics_context.zig").GraphicsContext;
 const Swapchain = @import("swapchain.zig").Swapchain;
 const Allocator = std.mem.Allocator;

generator/index.zig

@@ -1,4 +1,6 @@
 pub const generateVk = @import("vulkan/generator.zig").generate;
+pub const VkGenerateStep = @import("vulkan/build-integration.zig").GenerateStep;
+pub const ShaderCompileStep = @import("build-integration.zig").ShaderCompileStep;
 
 test "main" {
     _ = @import("xml.zig");