Added draw package as renderer focused on mixed use layout / 2D / 3D scene applications (#7)

Co-authored-by: Zachary Levy <zachary@sunforge.is>
Reviewed-on: #7

meta/main.odin

@@ -0,0 +1,51 @@
+package meta
+
+import "core:fmt"
+import "core:os"
+
+Command :: struct {
+	name:        string,
+	description: string,
+	run:         proc() -> bool,
+}
+
+COMMANDS :: []Command {
+	{
+		name = "gen-shaders",
+		description = "Compile GLSL shaders to SPIR-V and Metal Shading Language.",
+		run = proc() -> bool {
+			return gen_shaders("draw/shaders/source", "draw/shaders/generated")
+		},
+	},
+}
+
+main :: proc() {
+	args := os.args[1:]
+
+	if len(args) == 0 {
+		print_usage()
+		return
+	}
+
+	command_name := args[0]
+	for command in COMMANDS {
+		if command.name == command_name {
+			if !command.run() do os.exit(1)
+			return
+		}
+	}
+
+	fmt.eprintfln("Unknown command '%s'.", command_name)
+	fmt.eprintln()
+	print_usage()
+	os.exit(1)
+}
+
+print_usage :: proc() {
+	fmt.eprintln("Usage: meta <command>")
+	fmt.eprintln()
+	fmt.eprintln("Commands:")
+	for command in COMMANDS {
+		fmt.eprintfln("  %-20s %s", command.name, command.description)
+	}
+}