wasm/infra: Add build scripts for WebGPU

New build script for WASM with WebGPU.

Run `wasm_webgpu_build.sh` to have WebGPU WASM binary

cross/wasm_webgpu.txt

@@ -0,0 +1,21 @@
+[binaries]
+cpp = 'EMSDK:upstream/emscripten/em++.py'
+ar = 'EMSDK:upstream/emscripten/emar.py'
+strip = '-strip'
+
+[properties]
+root = 'EMSDK:upstream/emscripten/system'
+shared_lib_suffix = 'js'
+static_lib_suffix = 'js'
+shared_module_suffix = 'js'
+exe_suffix = 'js'
+
+[built-in options]
+cpp_args = ['-Wshift-negative-value', '-flto', '-Os', '-fno-exceptions']
+cpp_link_args = ['-lembind', '-sMODULARIZE=1', '-sUSE_WEBGPU=1', '-sASYNCIFY=1', '-sFORCE_FILESYSTEM=1', '-sALLOW_MEMORY_GROWTH=1', '-sEXPORT_ES6=1', '-sSINGLE_FILE=1']
+
+[host_machine]
+system = 'emscripten'
+cpu_family = 'wasm32'
+cpu = 'wasm32'
+endian = 'little'

src/renderer/wg_engine/meson.build

@@ -21,7 +21,10 @@ source_file = [
     'tvgWgShaderTypes.cpp'
 ]
 
-wgpu_dep = dependency('wgpu_native')
+wgpu_dep = []
+if not get_option('bindings').contains('wasm_beta')
+    wgpu_dep = dependency('wgpu_native')
+endif
 
 engine_dep += [declare_dependency(
     dependencies        : wgpu_dep,

wasm_webgpu_build.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+#https://github.com/thorvg/thorvg/wiki/WebGPU-Raster-Engine-Development
+
+if [ ! -d "./build_wasm" ]; then
+    sed "s|EMSDK:|$1|g" ./cross/wasm_webgpu.txt > /tmp/.wasm_cross.txt
+    meson -Db_lto=true -Ddefault_library=static -Dstatic=true -Dloaders="all" -Dsavers="all" -Dthreads=false -Dbindings="wasm_beta" -Dengines="wg_beta" --cross-file /tmp/.wasm_cross.txt build_wasm
+fi
+
+ninja -C build_wasm/
+ls -lrt build_wasm/src/bindings/wasm/thorvg-wasm.*