Initial draw package

meta/gen_shaders.odin

@@ -0,0 +1,141 @@
+package meta
+
+import "core:fmt"
+import "core:os"
+import "core:strings"
+
+// Compiles all GLSL shaders in source_dir to both SPIR-V (.spv) and
+// Metal Shading Language (.metal), writing results to generated_dir.
+// Overwrites any previously generated files with matching names.
+// Requires `glslangValidator` and `spirv-cross` on PATH.
+gen_shaders :: proc(source_dir, generated_dir: string) -> (success: bool) {
+	if !verify_shader_tool("glslangValidator") do return false
+	if !verify_shader_tool("spirv-cross") do return false
+
+	source_entries, read_err := os.read_all_directory_by_path(source_dir, context.temp_allocator)
+	if read_err != nil {
+		fmt.eprintfln("Failed to read shader source directory '%s': %v", source_dir, read_err)
+		return false
+	}
+	shader_names := make([dynamic]string, len = 0, cap = 24, allocator = context.temp_allocator)
+
+	for entry in source_entries {
+		if strings.has_suffix(entry.name, ".vert") || strings.has_suffix(entry.name, ".frag") {
+			append(&shader_names, entry.name)
+		}
+	}
+
+	if len(shader_names) == 0 {
+		fmt.eprintfln("No shader source files (.vert, .frag) found in '%s'.", source_dir)
+		return false
+	}
+	if os.exists(generated_dir) {
+		rmdir_err := os.remove_all(generated_dir)
+		if rmdir_err != nil {
+			fmt.eprintfln("Failed to remove old output directory '%s': %v", generated_dir, rmdir_err)
+			return false
+		}
+	}
+	mkdir_err := os.mkdir(generated_dir)
+	if mkdir_err != nil {
+		fmt.eprintfln("Failed to create output directory '%s': %v", generated_dir, mkdir_err)
+		return false
+	}
+
+	compiled_count := 0
+	for shader_name in shader_names {
+		source_path := fmt.tprintf("%s/%s", source_dir, shader_name)
+		spv_path := fmt.tprintf("%s/%s.spv", generated_dir, shader_name)
+		metal_path := fmt.tprintf("%s/%s.metal", generated_dir, shader_name)
+
+		fmt.printfln("[GLSL -> SPIR-V]  %s", shader_name)
+		if !compile_glsl_to_spirv(source_path, spv_path) do continue
+
+		fmt.printfln("[SPIR-V -> MSL]   %s", shader_name)
+		if !compile_spirv_to_msl(spv_path, metal_path) do continue
+
+		compiled_count += 1
+	}
+
+	total := len(shader_names)
+	if compiled_count == total {
+		fmt.printfln("Successfully compiled all %d shaders.", total)
+		return true
+	}
+
+	fmt.eprintfln("%d of %d shaders failed to compile.", total - compiled_count, total)
+	return false
+}
+
+verify_shader_tool :: proc(tool_name: string) -> bool {
+	_, _, _, err := os.process_exec(
+		os.Process_Desc{command = []string{tool_name, "--version"}},
+		context.temp_allocator,
+	)
+
+	if err != nil {
+		fmt.eprintfln("Required tool '%s' not found on PATH.", tool_name)
+		if tool_name == "glslangValidator" {
+			fmt.eprintln("\tInstall the Vulkan SDK or the glslang package:")
+			fmt.eprintln("\t  macOS:   brew install glslang")
+			fmt.eprintln("\t  Arch:    sudo pacman -S glslang")
+			fmt.eprintln("\t  Debian:  sudo apt install glslang-tools")
+		} else if tool_name == "spirv-cross" {
+			fmt.eprintln("\tInstall SPIRV-Cross:")
+			fmt.eprintln("\t  macOS:   brew install spirv-cross")
+			fmt.eprintln("\t  Arch:    sudo pacman -S spirv-cross")
+			fmt.eprintln("\t  Debian:  sudo apt install spirv-cross")
+		}
+		return false
+	}
+
+	return true
+}
+
+compile_glsl_to_spirv :: proc(source_path, output_path: string) -> bool {
+	state, stdout_bytes, stderr_bytes, err := os.process_exec(
+		os.Process_Desc{command = []string{"glslangValidator", "-V", source_path, "-o", output_path}},
+		context.temp_allocator,
+	)
+
+	if err != nil {
+		fmt.eprintfln("\tFailed to run glslangValidator for '%s': %v", source_path, err)
+		return false
+	}
+
+	if !state.success {
+		fmt.eprintfln("\tglslangValidator failed for '%s' (exit code %d):", source_path, state.exit_code)
+		print_tool_output(stdout_bytes, stderr_bytes)
+		return false
+	}
+
+	return true
+}
+
+compile_spirv_to_msl :: proc(spv_path, output_path: string) -> bool {
+	state, stdout_bytes, stderr_bytes, err := os.process_exec(
+		os.Process_Desc{command = []string{"spirv-cross", "--msl", spv_path, "--output", output_path}},
+		context.temp_allocator,
+	)
+
+	if err != nil {
+		fmt.eprintfln("\tFailed to run spirv-cross for '%s': %v", spv_path, err)
+		return false
+	}
+
+	if !state.success {
+		fmt.eprintfln("\tspirv-cross failed for '%s' (exit code %d):", spv_path, state.exit_code)
+		print_tool_output(stdout_bytes, stderr_bytes)
+		return false
+	}
+
+	return true
+}
+
+print_tool_output :: proc(stdout_bytes, stderr_bytes: []u8) {
+	stderr_text := strings.trim_right_space(transmute(string)stderr_bytes)
+	stdout_text := strings.trim_right_space(transmute(string)stdout_bytes)
+
+	if len(stderr_text) > 0 do fmt.eprintfln("\t%s", stderr_text)
+	if len(stdout_text) > 0 do fmt.eprintfln("\t%s", stdout_text)
+}