Fix trash on sides of screen in full screen mode.

Also, added a bit more diagnostics for the case when the audio subsystem
fails to initialize.

src/sound.cpp

@@ -79,6 +79,7 @@ void SoundInit(void)
 	if (device == 0)
 	{
 		WriteLog("Sound: Failed to initialize SDL sound.\n");
+		WriteLog("SDL sez: %s\n", SDL_GetError());
 		return;
 	}
 

src/video.cpp

@@ -24,8 +24,6 @@
 //   there [DONE]
 //
 
-// Display routines seem MUCH slower now... !!! INVESTIGATE !!! [not anymore]
-
 #include "video.h"
 
 #include <string.h>					// for memset()
@@ -605,9 +603,9 @@ static void Render80ColumnText(void)
 static void RenderLoRes(uint16_t toLine/*= 24*/)
 {
 // NOTE: The green mono rendering doesn't skip every other line... !!! FIX !!!
-//       Also, we could set up three different Render functions depending on which
-//       render type was set and call it with a function pointer. Would be faster
-//       then the nested ifs we have now.
+//       Also, we could set up three different Render functions depending on
+//       which render type was set and call it with a function pointer. Would
+//       be faster than the nested ifs we have now.
 /*
 Note that these colors correspond to the bit patterns generated by the numbers 0-F in order:
 Color #s correspond to the bit patterns in reverse... Interesting!
@@ -1232,6 +1230,7 @@ void RenderAppleScreen(SDL_Renderer * renderer)
 	SDL_LockTexture(sdlTexture, NULL, (void **)&scrBuffer, &scrPitch);
 	RenderVideoFrame();
 	SDL_UnlockTexture(sdlTexture);
+	SDL_RenderClear(renderer);		// Without this, full screen has trash on the sides
 	SDL_RenderCopy(renderer, sdlTexture, NULL, NULL);
 }