Workaround framebuffer bug if screen width >1024

Framebuffer can't properly blit the image if width is >1024. Bump the
buffer size to 4096 so widths up to 4096 (which should be enough for now)
work.

src/emulation/sky/draw.cpp

@@ -571,6 +571,8 @@ namespace sky
 			int16_t nxe = ceil(sl2 * j + c2);
 			int16_t dstart = nxs;
 			int16_t dend = nxe;
+			if(nxs >= nxe)
+				continue;
 			uint32_t cstep = 255 * 65536 / (nxe - nxs + 1);
 			uint32_t color = 0;
 			if(true) {
@@ -634,6 +636,8 @@ namespace sky
 			int16_t nxe = ceil(sl2 * j + c2);
 			int16_t dstart = nxs;
 			int16_t dend = nxe;
+			if(nxe <= nxs)
+				continue;
 			uint32_t cstep = 255 * 65536 / (nxe - nxs + 1);
 			uint32_t color = 0;
 			int16_t cstart = ccenter;
@@ -720,6 +724,8 @@ namespace sky
 			int16_t nxe = ceil(sl2 * j + c2);
 			int16_t dstart = nxs;
 			int16_t dend = nxe;
+			if(nxe <= nxs)
+				continue;
 			uint32_t cstep = 255 * 65536 / (nxe - nxs + 1);
 			uint32_t color = 0;
 			if(j < ymin2 && p1.y != p2.y) {

src/emulation/sky/framebuffer.cpp

@@ -143,7 +143,7 @@ namespace sky
 	{
 		uint16_t minline = 0x8f;
 		uint16_t maxline = 0x8f;
-		uint16_t ptr = 320 * 0x8f + 0x2a + (col / 3);
+		uint16_t ptr = 320 * 0x8f + 0x2a + (col / FB_SCALE);
 		uint32_t px = origbuffer[ptr] ;
 		while(origbuffer[ptr] == px)
 			ptr -= 320;
@@ -152,7 +152,7 @@ namespace sky
 		while(origbuffer[ptr] == px)
 			ptr += 320;
 		maxline = ptr / 320 - 1;
-		render_framebuffer_vline(col + 3 * 0x2a, minline, maxline, c | 0xFF000000U);
+		render_framebuffer_vline(col + FB_SCALE * 0x2a, minline, maxline, c | 0xFF000000U);
 	}
 
 	void blink_between(unsigned x, unsigned y, unsigned w, unsigned h, uint32_t c1, uint32_t c2)

src/emulation/sky/physics.cpp

@@ -282,7 +282,7 @@ namespace sky
 			return;
 		}
 		if(!death && vspeed < 0)
-			noise(sound_bounce);
+			noise(sound_bounce, false);
 		vspeed = -((5 * static_cast<int16_t>(vspeed)) / 10);
 	}
 	void physics::check_landing(level& stage) throw()

src/emulation/sky/sound.cpp

@@ -72,6 +72,7 @@ namespace sky
 		subsample = 0;
 		mdr = 128;
 		rate = 128;
+		_hipri = 0;
 	}
 
 	void active_sfx_dma::reset(const struct sound& snd)
@@ -128,9 +129,10 @@ namespace sky
 	sound_noise_maker::~sound_noise_maker() {}
 	void sound_noise_maker::operator()(int sound, bool hipri)
 	{
-		if(!hipri && dma.busy())
+		if(!hipri && dma.hipri() && dma.busy())
 			return;
 		dma.reset(snds[sound]);
+		dma.hipri(hipri);
 	}
 
 	sound_noise_maker gsfx(soundfx, _gstate.dma);

src/emulation/sky/sound.hpp

@@ -56,13 +56,16 @@ namespace sky
 		void reset(const struct sound& snd);
 		void fetch(struct sounds& snds, int16_t* buffer, size_t samples);	//Stereo!
 		bool busy() { return (left > 0); }
+		bool hipri() { return (_hipri > 0); }
+		void hipri(bool hi) { _hipri = hi ? 1 : 0; }
 	private:
 		uint8_t access(const struct sounds& snds, uint32_t addr) { snds.access(addr); }
 		int64_t left;
 		uint32_t pointer;
 		uint32_t subsample;
 		uint32_t padA;
-		uint16_t padB;
+		uint8_t padB;
+		uint8_t _hipri;
 		uint8_t mdr;
 		uint8_t rate;
 	};

src/library/framebuffer.cpp

@@ -324,7 +324,7 @@ framebuffer<X>::~framebuffer() throw()
 		delete[] mem;
 }
 
-#define DECBUF_SIZE 1024
+#define DECBUF_SIZE 4096
 
 template<bool X>
 void framebuffer<X>::copy_from(framebuffer_raw& scr, size_t hscale, size_t vscale) throw()