diff --git a/build.zig b/build.zig index 3a70615..680c1f9 100644 --- a/build.zig +++ b/build.zig @@ -56,7 +56,7 @@ pub const ResourceGenStep = struct { } pub fn addShader(self: *ResourceGenStep, name: []const u8, source: []const u8) void { - const shader_out_path = self.shader_step.add(source); + const shader_out_path = self.shader_step.add(source, .{}); var writer = self.resources.writer(); writer.print("pub const {s} = @embedFile(\"", .{name}) catch unreachable; diff --git a/generator/build_integration.zig b/generator/build_integration.zig index f6038c9..07f42ee 100644 --- a/generator/build_integration.zig +++ b/generator/build_integration.zig @@ -3,10 +3,27 @@ const path = std.fs.path; const Builder = std.build.Builder; const Step = std.build.Step; +/// Stage the shader should be built for. This is passed to the -fshader-stage +/// argument when invoking glslc. +pub const ShaderStage = enum { + vertex, + fragment, + tesscontrol, + tesseval, + geometry, + compute, +}; + /// Utility functionality to help with compiling shaders from build.zig. /// Invokes glslc (or another shader compiler passed to `init`) for each shader /// added via `addShader`. pub const ShaderCompileStep = struct { + const AddFileParams = struct { + entry_point: ?[]const u8 = null, + stage: ?ShaderStage = null, + output_filename: ?[]const u8 = null, + }; + /// Structure representing a shader to be compiled. const Shader = struct { /// The path to the shader, relative to the current build root. @@ -14,6 +31,13 @@ pub const ShaderCompileStep = struct { /// The full output path where the compiled shader binary is placed. full_out_path: []const u8, + + /// The entry point to use when compiling the shader. + entry_point: ?[]const u8, + + /// The stage to use when building. If not null, this is passed to + /// the -fshader-stage argument. + stage: ?ShaderStage, }; step: Step, @@ -45,16 +69,15 @@ pub const ShaderCompileStep = struct { /// Add a shader to be compiled. `src` is shader source path, relative to the project root. /// Returns the full path where the compiled binary will be stored upon successful compilation. /// This path can then be used to include the binary into an executable, for example by passing it - /// to @embedFile via an additional generated file. - pub fn add(self: *ShaderCompileStep, src: []const u8) []const u8 { - const output_filename = std.fmt.allocPrint(self.builder.allocator, "{s}.spv", .{ src }) catch unreachable; + /// to @embedFile via an additional generated file. `entry_point` is the entry point to pass to the compiler. + /// `stage` is an optional shader stage to pass to the compiler with the flag `-fshader-stage` when building the shader. + pub fn add(self: *ShaderCompileStep, src: []const u8, params: AddFileParams) []const u8 { const full_out_path = path.join(self.builder.allocator, &[_][]const u8{ self.builder.build_root, self.builder.cache_root, - self.output_dir, - output_filename, + if (params.output_filename) |out| out else std.fmt.allocPrint(self.builder.allocator, "{s}.spv", .{src}) catch unreachable, }) catch unreachable; - self.shaders.append(.{ .source_path = src, .full_out_path = full_out_path }) catch unreachable; + self.shaders.append(.{ .source_path = src, .full_out_path = full_out_path, .entry_point = params.entry_point, .stage = params.stage }) catch unreachable; return full_out_path; } @@ -63,18 +86,30 @@ pub const ShaderCompileStep = struct { const self = @fieldParentPtr(ShaderCompileStep, "step", step); const cwd = std.fs.cwd(); - const cmd = try self.builder.allocator.alloc([]const u8, self.glslc_cmd.len + 3); + const cmd = try self.builder.allocator.alloc([]const u8, self.glslc_cmd.len + 5); for (self.glslc_cmd) |part, i| { cmd[i] = part; } - cmd[cmd.len - 2] = "-o"; for (self.shaders.items) |shader| { + var argc: usize = cmd.len - 2; + + if (shader.entry_point) |entry_point| { + cmd[argc - 3] = try std.fmt.allocPrint(self.builder.allocator, "-fentry-point={s}", .{entry_point}); + argc += 1; + } + + if (shader.stage) |stage| { + cmd[argc - 3] = try std.fmt.allocPrint(self.builder.allocator, "-fshader-stage={s}", .{@tagName(stage)}); + argc += 1; + } + const dir = path.dirname(shader.full_out_path).?; try cwd.makePath(dir); - cmd[cmd.len - 3] = shader.source_path; - cmd[cmd.len - 1] = shader.full_out_path; - try self.builder.spawnChild(cmd); + cmd[argc - 3] = shader.source_path; + cmd[argc - 2] = "-o"; + cmd[argc - 1] = shader.full_out_path; + try self.builder.spawnChild(cmd[0..argc]); } } }; diff --git a/generator/index.zig b/generator/index.zig index 05ca2fe..ddb1440 100644 --- a/generator/index.zig +++ b/generator/index.zig @@ -1,5 +1,6 @@ pub const generateVk = @import("vulkan/generator.zig").generate; pub const VkGenerateStep = @import("vulkan/build_integration.zig").GenerateStep; +pub const ShaderStage = @import("build_integration.zig").ShaderStage; pub const ShaderCompileStep = @import("build_integration.zig").ShaderCompileStep; test "main" {