WIP: WebAssembly support

GDMP/io/BUILD

@@ -9,6 +9,7 @@ cc_library(
     ] + select({
         "//mediapipe:android": [":camera_helper_android"],
         "//mediapipe:ios": [":camera_helper_ios"],
+        "//GDMP/web:web": [],
         "//conditions:default": [":camera_helper_cv"],
     }),
 )

GDMP/web/BUILD

@@ -0,0 +1,23 @@
+load("@emsdk//emscripten_toolchain:wasm_rules.bzl", "wasm_cc_binary")
+
+config_setting(
+    name = "web",
+    values = {
+        "crosstool_top": "@emsdk//emscripten_toolchain:everything",
+    },
+    visibility = ["//visibility:public"],
+)
+
+cc_binary(
+    name = "GDMP",
+    linkopts = [
+        "-s STANDALONE_WASM=1",
+        "--no-entry",
+    ],
+    deps = ["//GDMP"],
+)
+
+wasm_cc_binary(
+    name = "GDMP_wasm",
+    cc_target = ":GDMP",
+)

build.py

@@ -18,6 +18,7 @@
     "android": "//GDMP/android:GDMP",
     "desktop": "//GDMP/desktop:GDMP",
     "ios": "//GDMP/ios:GDMP",
+    "web": "//GDMP/web:GDMP_wasm",
 }
 
 TARGET_ARGS = {
@@ -39,6 +40,11 @@
         "--apple_generate_dsym=false",
         "--config=ios",
     ],
+    "web": [
+        "--crosstool_top=@emsdk//emscripten_toolchain:everything",
+        "--host_crosstool_top=@bazel_tools//tools/cpp:toolchain",
+        "--define', 'MEDIAPIPE_DISABLE_GPU=1",
+    ],
 }
 
 
@@ -153,6 +159,9 @@ def copy_ios(args: Namespace):
         f.extractall(output)
 
 
+def copy_web(args: Namespace):
+    pass
+
 def copy_output(args: Namespace):
     target: str = args.target
     output: str = args.output
@@ -163,6 +172,7 @@ def copy_output(args: Namespace):
         "android": copy_android,
         "desktop": copy_desktop,
         "ios": copy_ios,
+        "web": copy_web,
     }
     copy_actions[target](args)
 

patch/mediapipe/00-WORKSPACE.diff

@@ -22,3 +22,24 @@ diff --git a/WORKSPACE b/WORKSPACE
  # Protobuf expects an //external:python_headers target
  bind(
      name = "python_headers",
+@@ -519,6 +533,20 @@ http_archive(
+ load("@build_bazel_rules_nodejs//:repositories.bzl", "build_bazel_rules_nodejs_dependencies")
+ build_bazel_rules_nodejs_dependencies()
+
++# Emscripten toolchain
++http_archive(
++    name = "emsdk",
++    sha256 = "d55e3c73fc4f8d1fecb7aabe548de86bdb55080fe6b12ce593d63b8bade54567",
++    strip_prefix = "emsdk-3891e7b04bf8cbb3bc62758e9c575ae096a9a518/bazel",
++    url = "https://github.com/emscripten-core/emsdk/archive/3891e7b04bf8cbb3bc62758e9c575ae096a9a518.tar.gz",
++)
++
++load("@emsdk//:deps.bzl", emsdk_deps = "deps")
++emsdk_deps()
++
++load("@emsdk//:emscripten_deps.bzl", emsdk_emscripten_deps = "emscripten_deps")
++emsdk_emscripten_deps(emscripten_version = "2.0.31")
++
+ # fetches nodejs, npm, and yarn
+ load("@build_bazel_rules_nodejs//:index.bzl", "node_repositories", "yarn_install")
+ node_repositories()