1 files changed, 16 insertions, 11 deletions

diff --git a/src/library_sdl.js b/src/library_sdl.js
index 80734d95..04e8fc18 100644
--- a/src/library_sdl.js
+++ b/src/library_sdl.js
@@ -215,7 +215,6 @@ var LibrarySDL = {
     makeSurface: function(width, height, flags, usePageCanvas, source, rmask, gmask, bmask, amask) {
       flags = flags || 0;
       var surf = _malloc({{{ C_STRUCTS.SDL_Surface.__size__ }}});  // SDL_Surface has 15 fields of quantum size
-      var buffer = _malloc(width*height*4); // TODO: only allocate when locked the first time
       var pixelFormat = _malloc({{{ C_STRUCTS.SDL_PixelFormat.__size__ }}});
       flags |= 1; // SDL_HWSURFACE - this tells SDL_MUSTLOCK that this needs to be locked
 
@@ -229,7 +228,7 @@ var LibrarySDL = {
       {{{ makeSetValue('surf', C_STRUCTS.SDL_Surface.h, 'height', 'i32') }}};       // SDL_Surface.h
       {{{ makeSetValue('surf', C_STRUCTS.SDL_Surface.pitch, 'width * bpp', 'i32') }}};      // SDL_Surface.pitch, assuming RGBA or indexed for now,
                                                                                // since that is what ImageData gives us in browsers
-      {{{ makeSetValue('surf', C_STRUCTS.SDL_Surface.pixels, 'buffer', 'void*') }}};     // SDL_Surface.pixels
+      {{{ makeSetValue('surf', C_STRUCTS.SDL_Surface.pixels, '0', 'void*') }}};     // SDL_Surface.pixels, lazily initialized inside of SDL_LockSurface
       {{{ makeSetValue('surf', C_STRUCTS.SDL_Surface.clip_rect, '0', 'i32*') }}};     // SDL_Surface.offset
 
       {{{ makeSetValue('surf', C_STRUCTS.SDL_Surface.refcount, '1', 'i32') }}};
@@ -274,7 +273,7 @@ var LibrarySDL = {
         canvas: canvas,
         ctx: ctx,
         surf: surf,
-        buffer: buffer,
+        buffer: 0,
         pixelFormat: pixelFormat,
         alpha: 255,
         flags: flags,
@@ -337,7 +336,7 @@ var LibrarySDL = {
 
       var info = SDL.surfaces[surf];
       if (!info.usePageCanvas && info.canvas) SDL.canvasPool.push(info.canvas);
-      _free(info.buffer);
+      if (info.buffer) _free(info.buffer);
       _free(info.pixelFormat);
       _free(surf);
       SDL.surfaces[surf] = null;
@@ -986,6 +985,11 @@ var LibrarySDL = {
     surfData.locked++;
     if (surfData.locked > 1) return 0;
 
+    if (!surfData.buffer) {
+      surfData.buffer = _malloc(surfData.width * surfData.height * 4);
+      {{{ makeSetValue('surf', C_STRUCTS.SDL_Surface.pixels, 'surfData.buffer', 'void*') }}};
+    }
+
     // Mark in C/C++-accessible SDL structure
     // SDL_Surface has the following fields: Uint32 flags, SDL_PixelFormat *format; int w, h; Uint16 pitch; void *pixels; ...
     // So we have fields all of the same size, and 5 of them before us.
@@ -1723,6 +1727,7 @@ var LibrarySDL = {
         SDL.audio.pushAudio=function(ptr,sizeBytes) {
           try {
             --SDL.audio.numAudioTimersPending;
+            if (SDL.audio.paused) return;
 
             var sizeSamples = sizeBytes / SDL.audio.bytesPerSample; // How many samples fit in the callback buffer?
             var sizeSamplesPerChannel = sizeSamples / SDL.audio.channels; // How many samples per a single channel fit in the cb buffer?
@@ -1773,18 +1778,18 @@ var LibrarySDL = {
             SDL.audio.soundSource[SDL.audio.nextSoundSource]['start'](playtime);
             var buffer_duration = sizeSamplesPerChannel / SDL.audio.freq;
             SDL.audio.nextPlayTime = playtime + buffer_duration;
-            SDL.audio.nextSoundSource = (SDL.audio.nextSoundSource + 1) % 4;
+            // Timer will be scheduled before the buffer completed playing.
+            // Extra buffers are needed to avoid disturbing playing buffer.
+            SDL.audio.nextSoundSource = (SDL.audio.nextSoundSource + 1) % (SDL.audio.numSimultaneouslyQueuedBuffers + 2);
             var secsUntilNextCall = playtime-curtime;
             
             // Queue the next audio frame push to be performed when the previously queued buffer has finished playing.
-            if (SDL.audio.numAudioTimersPending == 0) {
-              var preemptBufferFeedMSecs = buffer_duration/2.0;
-              SDL.audio.timer = Browser.safeSetTimeout(SDL.audio.caller, Math.max(0.0, 1000.0*secsUntilNextCall-preemptBufferFeedMSecs));
-              ++SDL.audio.numAudioTimersPending;
-            }
+            var preemptBufferFeedMSecs = 1000*buffer_duration/2.0;
+            SDL.audio.timer = Browser.safeSetTimeout(SDL.audio.caller, Math.max(0.0, 1000.0*secsUntilNextCall-preemptBufferFeedMSecs));
+            ++SDL.audio.numAudioTimersPending;
 
             // If we are risking starving, immediately queue extra buffers.
-            if (secsUntilNextCall <= buffer_duration && SDL.audio.numAudioTimersPending < SDL.audio.numSimultaneouslyQueuedBuffers) {
+            if (SDL.audio.numAudioTimersPending < SDL.audio.numSimultaneouslyQueuedBuffers) {
               ++SDL.audio.numAudioTimersPending;
               Browser.safeSetTimeout(SDL.audio.caller, 1.0);
             }