Fix emscripten regressions.

src/application/sdl-app.cpp

@@ -1,7 +1,7 @@
 //
 //  Lol Engine
 //
-//  Copyright © 2010—2019 Sam Hocevar <sam@hocevar.net>
+//  Copyright © 2010—2020 Sam Hocevar <sam@hocevar.net>
 //
 //  Lol Engine is free software. It comes without any warranty, to
 //  the extent permitted by applicable law. You can redistribute it
@@ -41,6 +41,7 @@ sdl::app_display::app_display(char const *title, ivec2 res)
     /* Initialise SDL */
     if (!SDL_WasInit(0))
     {
+        msg::debug("initialising SDL\n");
         if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_NOPARACHUTE) < 0)
         {
             msg::error("cannot initialise SDL: %s\n", SDL_GetError());
@@ -51,18 +52,20 @@ sdl::app_display::app_display(char const *title, ivec2 res)
     // This seems to fix a bug we used to have at context swap. Maybe remove one day.
     SDL_GL_SetAttribute(SDL_GL_SHARE_WITH_CURRENT_CONTEXT, 1);
 
-#if 0
+#if !defined __EMSCRIPTEN__
     // Ask for GL 3.2 at least
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
-#endif
+
 #if LOL_BUILD_DEBUG
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_DEBUG_FLAG);
+#endif
 #endif
 
     int flags = SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE;
     if (window_size == ivec2(0))
         flags |= SDL_WINDOW_FULLSCREEN_DESKTOP;
+    msg::debug("initialising main window\n");
     m_window = SDL_CreateWindow(title,
         SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
         window_size.x, window_size.y, flags);
@@ -75,6 +78,7 @@ sdl::app_display::app_display(char const *title, ivec2 res)
     SDL_GetWindowSize(m_window, &res.x, &res.y);
 
     m_glcontext = SDL_GL_CreateContext(m_window);
+    SDL_GL_MakeCurrent(m_window, m_glcontext);
     msg::info("created GL context: %s\n", glGetString(GL_VERSION));
 
     /* Initialise everything */

src/base/features.cpp

@@ -1,7 +1,7 @@
 //
 //  Lol Engine
 //
-//  Copyright © 2010—2019 Sam Hocevar <sam@hocevar.net>
+//  Copyright © 2010—2020 Sam Hocevar <sam@hocevar.net>
 //
 //  Lol Engine is free software. It comes without any warranty, to
 //  the extent permitted by applicable law. You can redistribute it
@@ -19,6 +19,11 @@ bool has_threads()
 {
     static char const *var = getenv("LOL_NOTHREADS");
     static bool const disable_threads = var && var[0];
+#if defined __EMSCRIPTEN__ && !defined __EMSCRIPTEN_PTHREADS__
+    // For some reason hardware_concurrency() will return the actual number
+    // of threads/cores even though the system cannot spawn threads.
+    return false;
+#endif
     return !disable_threads && std::thread::hardware_concurrency() > 1;
 }
 

src/engine/ticker.cpp

@@ -1,7 +1,7 @@
 //
 //  Lol Engine
 //
-//  Copyright © 2010—2019 Sam Hocevar <sam@hocevar.net>
+//  Copyright © 2010—2020 Sam Hocevar <sam@hocevar.net>
 //
 //  Lol Engine is free software. It comes without any warranty, to
 //  the extent permitted by applicable law. You can redistribute it
@@ -30,6 +30,7 @@ class ticker_data
 public:
     ticker_data()
     {
+        msg::debug("platform %s threads\n", has_threads() ? "has" : "has no");
         if (has_threads())
         {
             gamethread = std::make_unique<thread>(std::bind(&ticker_data::GameThreadMain, this));
@@ -557,6 +558,7 @@ void Ticker::SetStateWhenMatch(entity * /* entity */, uint32_t /* state */,
 
 void ticker::setup(float fps)
 {
+    msg::debug("creating ticker\n");
     data = std::make_unique<ticker_data>();
     data->fps = fps;
 }

src/gpu/debug.cpp

@@ -1,7 +1,7 @@
 //
 //  Lol Engine
 //
-//  Copyright © 2010—2019 Sam Hocevar <sam@hocevar.net>
+//  Copyright © 2010—2020 Sam Hocevar <sam@hocevar.net>
 //
 //  Lol Engine is free software. It comes without any warranty, to
 //  the extent permitted by applicable law. You can redistribute it
@@ -17,7 +17,7 @@
 namespace lol
 {
 
-#if LOL_BUILD_DEBUG
+#if LOL_BUILD_DEBUG && !defined __EMSCRIPTEN__
 static std::map<GLenum, char const *> gl_dbg_source_to_str
 {
     { GL_DEBUG_SOURCE_API, "API" },
@@ -88,7 +88,7 @@ static void LOL_ATTR_STDCALL
 
 void gpu::setup_debug()
 {
-#if LOL_BUILD_DEBUG
+#if LOL_BUILD_DEBUG && !defined __EMSCRIPTEN__
     GLint glflags;
     glGetIntegerv(GL_CONTEXT_FLAGS, &glflags);
 

src/gpu/vertexbuffer.cpp

@@ -14,6 +14,13 @@
 
 #include "lolgl.h"
 
+// FIXME: can we make this more generic?
+#if defined __EMSCRIPTEN__
+    #define glGenVertexArrays glGenVertexArraysOES
+    #define glBindVertexArray glBindVertexArrayOES
+    #define glDeleteVertexArrays glDeleteVertexArraysOES
+#endif
+
 // FIXME: fine-tune this define
 #if defined LOL_USE_GLEW || defined HAVE_GL_2X || defined HAVE_GLES_2X