godot/platform/javascript/detect.py
Fabio Alessandrelli d8bd54fbf2 [HTML5] Add PWA support to the editor page.
This allows to install it as an app, and provide offline support (after
the first run).
Practically, this boils down to adding a JSON file as a manifest, an
offline page to be displayed when the cached files are not avaialble,
and a JS file to cache resources and return them.

The reason for the "first run requirements" is that some browsers, will
emit an "install" by just visiting the page (to see if the JS code is
compatibile), and we do not want to force casual visitors to just
download the 10 MiB+ compressed editor WebAssembly file without pressing
the start button.

Special thanks to Hugo Locurcio (Calinou) for the initial work.
2021-03-08 17:06:24 +01:00

244 lines
9.2 KiB
Python

import os
import sys
from emscripten_helpers import (
run_closure_compiler,
create_engine_file,
add_js_libraries,
add_js_pre,
add_js_externs,
create_template_zip,
)
from methods import get_compiler_version
from SCons.Util import WhereIs
def is_active():
return True
def get_name():
return "JavaScript"
def can_build():
return WhereIs("emcc") is not None
def get_opts():
from SCons.Variables import BoolVariable
return [
("initial_memory", "Initial WASM memory (in MiB)", 16),
BoolVariable("use_assertions", "Use Emscripten runtime assertions", False),
BoolVariable("use_thinlto", "Use ThinLTO", False),
BoolVariable("use_ubsan", "Use Emscripten undefined behavior sanitizer (UBSAN)", False),
BoolVariable("use_asan", "Use Emscripten address sanitizer (ASAN)", False),
BoolVariable("use_lsan", "Use Emscripten leak sanitizer (LSAN)", False),
BoolVariable("use_safe_heap", "Use Emscripten SAFE_HEAP sanitizer", False),
# eval() can be a security concern, so it can be disabled.
BoolVariable("javascript_eval", "Enable JavaScript eval interface", True),
BoolVariable("threads_enabled", "Enable WebAssembly Threads support (limited browser support)", False),
BoolVariable("gdnative_enabled", "Enable WebAssembly GDNative support (produces bigger binaries)", False),
BoolVariable("use_closure_compiler", "Use closure compiler to minimize JavaScript code", False),
]
def get_flags():
return [
("tools", False),
("builtin_pcre2_with_jit", False),
# Disabling the mbedtls module reduces file size.
# The module has little use due to the limited networking functionality
# in this platform. For the available networking methods, the browser
# manages TLS.
("module_mbedtls_enabled", False),
]
def configure(env):
try:
env["initial_memory"] = int(env["initial_memory"])
except Exception:
print("Initial memory must be a valid integer")
sys.exit(255)
## Build type
if env["target"] == "release":
# Use -Os to prioritize optimizing for reduced file size. This is
# particularly valuable for the web platform because it directly
# decreases download time.
# -Os reduces file size by around 5 MiB over -O3. -Oz only saves about
# 100 KiB over -Os, which does not justify the negative impact on
# run-time performance.
env.Append(CCFLAGS=["-Os"])
env.Append(LINKFLAGS=["-Os"])
elif env["target"] == "release_debug":
env.Append(CCFLAGS=["-Os"])
env.Append(LINKFLAGS=["-Os"])
env.Append(CPPDEFINES=["DEBUG_ENABLED"])
# Retain function names for backtraces at the cost of file size.
env.Append(LINKFLAGS=["--profiling-funcs"])
else: # "debug"
env.Append(CPPDEFINES=["DEBUG_ENABLED"])
env.Append(CCFLAGS=["-O1", "-g"])
env.Append(LINKFLAGS=["-O1", "-g"])
env["use_assertions"] = True
if env["use_assertions"]:
env.Append(LINKFLAGS=["-s", "ASSERTIONS=1"])
if env["tools"]:
if not env["threads_enabled"]:
print("Threads must be enabled to build the editor. Please add the 'threads_enabled=yes' option")
sys.exit(255)
if env["initial_memory"] < 64:
print("Editor build requires at least 64MiB of initial memory. Forcing it.")
env["initial_memory"] = 64
elif env["builtin_icu"]:
env.Append(CCFLAGS=["-frtti"])
else:
# Disable exceptions and rtti on non-tools (template) builds
# These flags help keep the file size down.
env.Append(CCFLAGS=["-fno-exceptions", "-fno-rtti"])
# Don't use dynamic_cast, necessary with no-rtti.
env.Append(CPPDEFINES=["NO_SAFE_CAST"])
env.Append(LINKFLAGS=["-s", "INITIAL_MEMORY=%sMB" % env["initial_memory"]])
## Copy env variables.
env["ENV"] = os.environ
# LTO
if env["use_thinlto"]:
env.Append(CCFLAGS=["-flto=thin"])
env.Append(LINKFLAGS=["-flto=thin"])
elif env["use_lto"]:
env.Append(CCFLAGS=["-flto=full"])
env.Append(LINKFLAGS=["-flto=full"])
# Sanitizers
if env["use_ubsan"]:
env.Append(CCFLAGS=["-fsanitize=undefined"])
env.Append(LINKFLAGS=["-fsanitize=undefined"])
if env["use_asan"]:
env.Append(CCFLAGS=["-fsanitize=address"])
env.Append(LINKFLAGS=["-fsanitize=address"])
if env["use_lsan"]:
env.Append(CCFLAGS=["-fsanitize=leak"])
env.Append(LINKFLAGS=["-fsanitize=leak"])
if env["use_safe_heap"]:
env.Append(CCFLAGS=["-s", "SAFE_HEAP=1"])
env.Append(LINKFLAGS=["-s", "SAFE_HEAP=1"])
# Closure compiler
if env["use_closure_compiler"]:
# For emscripten support code.
env.Append(LINKFLAGS=["--closure", "1"])
# Register builder for our Engine files
jscc = env.Builder(generator=run_closure_compiler, suffix=".cc.js", src_suffix=".js")
env.Append(BUILDERS={"BuildJS": jscc})
# Add helper method for adding libraries, externs, pre-js.
env["JS_LIBS"] = []
env["JS_PRE"] = []
env["JS_EXTERNS"] = []
env.AddMethod(add_js_libraries, "AddJSLibraries")
env.AddMethod(add_js_pre, "AddJSPre")
env.AddMethod(add_js_externs, "AddJSExterns")
# Add method that joins/compiles our Engine files.
env.AddMethod(create_engine_file, "CreateEngineFile")
# Add method for creating the final zip file
env.AddMethod(create_template_zip, "CreateTemplateZip")
# Closure compiler extern and support for ecmascript specs (const, let, etc).
env["ENV"]["EMCC_CLOSURE_ARGS"] = "--language_in ECMASCRIPT6"
env["CC"] = "emcc"
env["CXX"] = "em++"
env["AR"] = "emar"
env["RANLIB"] = "emranlib"
# Use TempFileMunge since some AR invocations are too long for cmd.exe.
# Use POSIX-style paths, required with TempFileMunge.
env["ARCOM_POSIX"] = env["ARCOM"].replace("$TARGET", "$TARGET.posix").replace("$SOURCES", "$SOURCES.posix")
env["ARCOM"] = "${TEMPFILE(ARCOM_POSIX)}"
# All intermediate files are just LLVM bitcode.
env["OBJPREFIX"] = ""
env["OBJSUFFIX"] = ".bc"
env["PROGPREFIX"] = ""
# Program() output consists of multiple files, so specify suffixes manually at builder.
env["PROGSUFFIX"] = ""
env["LIBPREFIX"] = "lib"
env["LIBSUFFIX"] = ".bc"
env["LIBPREFIXES"] = ["$LIBPREFIX"]
env["LIBSUFFIXES"] = ["$LIBSUFFIX"]
env.Prepend(CPPPATH=["#platform/javascript"])
env.Append(CPPDEFINES=["JAVASCRIPT_ENABLED", "UNIX_ENABLED"])
if env["javascript_eval"]:
env.Append(CPPDEFINES=["JAVASCRIPT_EVAL_ENABLED"])
if env["threads_enabled"] and env["gdnative_enabled"]:
print("Threads and GDNative support can't be both enabled due to WebAssembly limitations")
sys.exit(255)
# Thread support (via SharedArrayBuffer).
if env["threads_enabled"]:
env.Append(CPPDEFINES=["PTHREAD_NO_RENAME"])
env.Append(CCFLAGS=["-s", "USE_PTHREADS=1"])
env.Append(LINKFLAGS=["-s", "USE_PTHREADS=1"])
env.Append(LINKFLAGS=["-s", "PTHREAD_POOL_SIZE=8"])
env.Append(LINKFLAGS=["-s", "WASM_MEM_MAX=2048MB"])
env.extra_suffix = ".threads" + env.extra_suffix
else:
env.Append(CPPDEFINES=["NO_THREADS"])
if env["gdnative_enabled"]:
major, minor, patch = get_compiler_version(env)
if major < 2 or (major == 2 and minor == 0 and patch < 10):
print("GDNative support requires emscripten >= 2.0.10, detected: %s.%s.%s" % (major, minor, patch))
sys.exit(255)
env.Append(CCFLAGS=["-s", "RELOCATABLE=1"])
env.Append(LINKFLAGS=["-s", "RELOCATABLE=1"])
env.extra_suffix = ".gdnative" + env.extra_suffix
# Reduce code size by generating less support code (e.g. skip NodeJS support).
env.Append(LINKFLAGS=["-s", "ENVIRONMENT=web,worker"])
# Wrap the JavaScript support code around a closure named Godot.
env.Append(LINKFLAGS=["-s", "MODULARIZE=1", "-s", "EXPORT_NAME='Godot'"])
# Allow increasing memory buffer size during runtime. This is efficient
# when using WebAssembly (in comparison to asm.js) and works well for
# us since we don't know requirements at compile-time.
env.Append(LINKFLAGS=["-s", "ALLOW_MEMORY_GROWTH=1"])
# This setting just makes WebGL 2 APIs available, it does NOT disable WebGL 1.
env.Append(LINKFLAGS=["-s", "USE_WEBGL2=1"])
# Do not call main immediately when the support code is ready.
env.Append(LINKFLAGS=["-s", "INVOKE_RUN=0"])
# Allow use to take control of swapping WebGL buffers.
env.Append(LINKFLAGS=["-s", "OFFSCREEN_FRAMEBUFFER=1"])
# callMain for manual start.
env.Append(LINKFLAGS=["-s", "EXTRA_EXPORTED_RUNTIME_METHODS=['callMain','cwrap']"])
# Add code that allow exiting runtime.
env.Append(LINKFLAGS=["-s", "EXIT_RUNTIME=1"])
# TODO remove once we have GLES support back (temporary fix undefined symbols due to dead code elimination).
env.Append(
LINKFLAGS=[
"-s",
"EXPORTED_FUNCTIONS=['_main', '_emscripten_webgl_get_current_context', '_emscripten_webgl_commit_frame', '_emscripten_webgl_create_context']",
]
)