Improve emscripten support

examples/PhysicallyBasedRendering/xmake.lua

@@ -1,7 +1,3 @@
 target("PBR")
 	add_deps("NazaraGraphics")
 	add_files("main.cpp")
-
-	if is_plat("wasm") then
-		add_ldflags("--preload-file assets/", {force = true})
-	end

examples/xmake.lua

@@ -3,5 +3,9 @@ option("examples", { description = "Build examples", default = true })
 if has_config("examples") then
 	set_group("Examples")
 
+	if is_plat("wasm") then
+		add_ldflags("--preload-file assets/", { force = true })
+	end
+
 	includes("*/xmake.lua")
 end

include/Nazara/OpenGLRenderer/Wrapper/Web/WebContext.hpp

@@ -7,12 +7,12 @@
 #ifndef NAZARA_OPENGLRENDERER_WRAPPER_WEB_WEBCONTEXT_HPP
 #define NAZARA_OPENGLRENDERER_WRAPPER_WEB_WEBCONTEXT_HPP
 
-#include <emscripten/html5.h>
 #include <Nazara/Prerequisites.hpp>
 #include <Nazara/Core/DynLib.hpp>
 #include <Nazara/OpenGLRenderer/Config.hpp>
 #include <Nazara/OpenGLRenderer/Wrapper/Context.hpp>
 #include <Nazara/Platform/WindowHandle.hpp>
+#include <emscripten/html5.h>
 #include <string>
 #include <type_traits>
 #include <unordered_set>

include/Nazara/Utility/BasicMainloop.hpp

@@ -4,10 +4,10 @@
 
 #pragma once
 
-#ifndef NAZARA_BASIC_MAINLOOP_HPP
-#define NAZARA_BASIC_MAINLOOP_HPP
+#ifndef NAZARA_UTILITY_BASICMAINLOOP_HPP
+#define NAZARA_UTILITY_BASICMAINLOOP_HPP
 
-#include <Nazara/Renderer.hpp>
+#include <Nazara/Platform/Window.hpp>
 
 #ifdef NAZARA_PLATFORM_WEB
 #include <emscripten/html5.h>
@@ -16,7 +16,7 @@
 namespace Nz
 {
 	template <typename CallbackT>
-	void BasicMainloop(RenderWindow& window, CallbackT&& callback)
+	void BasicMainloop(Window& window, CallbackT&& callback)
 	{
 #ifndef NAZARA_PLATFORM_WEB
 		while (window.IsOpen())
@@ -40,4 +40,4 @@ namespace Nz
 }
 
 
-#endif // NAZARA_BASIC_MAINLOOP_HPP
+#endif // NAZARA_UTILITY_BASICMAINLOOP_HPP

src/Nazara/OpenGLRenderer/OpenGLShaderModule.cpp

@@ -174,6 +174,10 @@ namespace Nz
 		m_states = states;
 		m_states.sanitized = true; //< Shader is always sanitized (because of keywords)
 
+#ifdef NAZARA_PLATFORM_WEB
+		m_states.optimize = true; //< Always remove unused code with emscripten (prevents errors on draw calls when no buffer is bound on a unused binding)
+#endif
+
 		nzsl::Ast::SanitizeVisitor::Options options = nzsl::GlslWriter::GetSanitizeOptions();
 		options.optionValues = states.optionValues;
 		options.moduleResolver = states.shaderModuleResolver;

src/Nazara/OpenGLRenderer/Wrapper/Context.cpp

@@ -147,11 +147,14 @@ namespace Nz::GL
 
 	GLenum Context::BindFramebuffer(GLuint fbo) const
 	{
+		// it looks like emscripten wants us to rebind the FBO everytime
+#ifndef NAZARA_PLATFORM_WEB
 		if (m_state.boundDrawFBO == fbo)
 			return GL_DRAW_FRAMEBUFFER;
 		else if (m_state.boundReadFBO == fbo)
 			return GL_READ_FRAMEBUFFER;
 		else
+#endif
 		{
 			if (!SetCurrentContext(this))
 				throw std::runtime_error("failed to activate context");
@@ -166,12 +169,10 @@ namespace Nz::GL
 	void Context::BindFramebuffer(FramebufferTarget target, GLuint fbo) const
 	{
 		auto& currentFbo = (target == FramebufferTarget::Draw) ? m_state.boundDrawFBO : m_state.boundReadFBO;
-#ifdef NAZARA_PLATFORM_WEB
-		constexpr bool isWeb = true;
-#else
-		constexpr bool isWeb = false;
+		// it looks like emscripten wants us to rebind the FBO everytime
+#ifndef NAZARA_PLATFORM_WEB
+		if (currentFbo != fbo)
 #endif
-		if (currentFbo != fbo || isWeb);
 		{
 			if (!SetCurrentContext(this))
 				throw std::runtime_error("failed to activate context");

src/Nazara/Platform/SDL2/WindowImpl.cpp

@@ -194,6 +194,10 @@ namespace Nz
 
 	WindowHandle WindowImpl::GetSystemHandle() const
 	{
+#ifdef NAZARA_PLATFORM_WEB
+		WindowHandle handle;
+		return handle;
+#else
 		SDL_SysWMinfo wmInfo;
 		SDL_VERSION(&wmInfo.version);
 
@@ -256,6 +260,7 @@ namespace Nz
 		}
 
 		return handle;
+#endif
 	}
 
 	bool WindowImpl::HasFocus() const

tests/GraphicsTest/xmake.lua

@@ -1,7 +1,3 @@
 target("GraphicsTest")
 	add_deps("NazaraGraphics")
 	add_files("main.cpp")
-
-	if is_plat("wasm") then
-		add_ldflags("--preload-file assets/", {force = true})
-	end

xmake.lua

@@ -176,9 +176,6 @@ if not has_config("embed_rendererbackends") then
 	end
 end
 
-add_ldflags("-g -s NO_DISABLE_EXCEPTION_CATCHING -s ALLOW_MEMORY_GROWTH=1")
-add_cxflags("-g -s NO_DISABLE_EXCEPTION_CATCHING")
-
 NazaraModules = modules
 
 includes("xmake/**.lua")
@@ -194,12 +191,27 @@ option("unitybuild", { description = "Build the engine using unity build", defau
 set_project("NazaraEngine")
 set_xmakever("2.7.3")
 
-add_requires("dr_wav", "entt 3.10.1", "fmt", "frozen", "kiwisolver", "minimp3", "ordered_map", "stb")
-if not is_plat("wasm") then
-	add_requires("chipmunk2d", "libsdl", "libflac", "efsw")
+add_requires("chipmunk2d", "dr_wav", "entt 3.10.1", "fmt", "frozen", "kiwisolver", "libflac", "minimp3", "ordered_map", "stb")
+add_requires("libvorbis", { configs = { with_vorbisenc = false } })
+
+if is_plat("wasm") then
+	-- Enable some flags for emscripten
+	add_cxflags("-g", "-sNO_DISABLE_EXCEPTION_CATCHING")
+	add_ldflags("-g", "-sNO_DISABLE_EXCEPTION_CATCHING", "-sALLOW_MEMORY_GROWTH", "-sWASM_BIGINT")
+	add_ldflags("-sERROR_ON_WASM_CHANGES_AFTER_LINK", { force = true })
+
+	-- we can't use wasm nzsl to compile shaders
+	if has_config("compile_shaders") then
+		add_requires("nzsl~host", { kind = "binary" })
+	end
+else
+	-- these libraries have ports in emscripten
+	add_requires("libsdl")
 	add_requires("freetype", { configs = { bzip2 = true, png = true, woff2 = true, zlib = true, debug = is_mode("debug") } })
-	add_requires("libvorbis", { configs = { with_vorbisenc = false } })
 	add_requires("openal-soft", { configs = { shared = true }})
+
+	-- these libraries aren't supported on emscripten
+	add_requires("efsw")
 	add_requires("newtondynamics3", { debug = is_plat("windows") and is_mode("debug") }) -- Newton doesn't like compiling in Debug on Linux
 end
 

xmake/rules/compile_shaders.lua

@@ -1,16 +1,19 @@
 -- Compile shaders to includables headers
 rule("nzsl.compile.shaders")
-	on_load(function (target)
-		target:add("packages", "nzsl")
-	end)
+	set_extensions(".nzsl", ".nzslb")
 
 	before_buildcmd_file(function (target, batchcmds, shaderfile, opt)
+		import("core.project.project")
 		import("core.tool.toolchain")
 
-		local nzslc = path.join(target:pkg("nzsl"):installdir(), "bin", "nzslc")
+		local nzsl = project.required_package("nzsl~host") or project.required_package("nzsl")
+		assert(nzsl, "nzsl package not found")
+
+		-- warning: project.required_package is not a stable interface, this may break in the future
+		local nzslc = path.join(nzsl:installdir(), "bin", "nzslc")
 
 		-- add commands
-		batchcmds:show_progress(opt.progress, "${color.build.object}compiling shader %s", shaderfile)
+		batchcmds:show_progress(opt.progress, "${color.build.object}compiling.shader %s", shaderfile)
 		local argv = { "--compile=nzslb-header", "--partial", "--optimize" }
 
 		-- handle --log-format
@@ -21,6 +24,7 @@ rule("nzsl.compile.shaders")
 
 		table.insert(argv, shaderfile)
 
+		-- on mingw we need run envs because of .dll dependencies which may be not part of the PATH
 		local envs
 		if is_plat("mingw") then
 			local mingw = toolchain.load("mingw")
@@ -28,7 +32,6 @@ rule("nzsl.compile.shaders")
 				envs = mingw:runenvs()
 			end
 		end
-	
 		batchcmds:vrunv(nzslc, argv, { curdir = ".", envs = envs })
 
 		local outputFile = path.join(path.directory(shaderfile), path.basename(shaderfile) .. ".nzslb.h")