@@ -41,11 +41,11 @@ readpixel(Uint8 *sprite, Uint8 h, Uint8 v)

 void

 clear(Ppu *p)

 {

-	int i;

-	for(i = p->height * p->width - 1; i >= 0; --i)

-		p->rgba[i] = p->colors[0];

-	for(i = p->height * p->width / 8 - 1; i >= 0; --i)

-		p->index[i] = 0;

+	int i, sz = p->height * p->width;

+	for(i = 0; i < sz; ++i) {

+		p->fg.pixels[i] = p->fg.colors[0];

+		p->bg.pixels[i] = p->bg.colors[0];

+	}

 }

 void

@@ -57,28 +57,23 @@ putcolors(Ppu *p, Uint8 *addr)

 			r = (*(addr + i / 2) >> (!(i % 2) << 2)) & 0x0f,

 			g = (*(addr + 2 + i / 2) >> (!(i % 2) << 2)) & 0x0f,

 			b = (*(addr + 4 + i / 2) >> (!(i % 2) << 2)) & 0x0f;

-		p->colors[i] = 0xff000000 | (r << 20) | (r << 16) | (g << 12) | (g << 8) | (b << 4) | b;

+		p->bg.colors[i] = 0xff000000 | (r << 20) | (r << 16) | (g << 12) | (g << 8) | (b << 4) | b;

+		p->fg.colors[i] = 0xff000000 | (r << 20) | (r << 16) | (g << 12) | (g << 8) | (b << 4) | b;

 	}

-	for(i = 4; i < 16; ++i) p->colors[i] = p->colors[i / 4];

+	p->fg.colors[0] = 0;

 	clear(p);

 }

 void

-putpixel(Ppu *p, Uint8 layer, Uint16 x, Uint16 y, Uint8 color)

+putpixel(Ppu *p, Layer *layer, Uint16 x, Uint16 y, Uint8 color)

 {

-	int rgba_i, index_i, shift_pixel, shift_layer;

 	if(x >= p->width || y >= p->height)

 		return;

-	rgba_i = y * p->width + x;

-	index_i = rgba_i >> 3;

-	shift_pixel = (rgba_i & 0x7) * 4;

-	shift_layer = shift_pixel + layer * 2;

-	p->index[index_i] = (p->index[index_i] & ~(0x3 << shift_layer)) | (color << shift_layer);

-	p->rgba[rgba_i] = p->colors[(p->index[index_i] >> shift_pixel) & 0xf];

+	layer->pixels[y * p->width + x] = layer->colors[color];

 }

 void

-puticn(Ppu *p, Uint8 layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint8 flipx, Uint8 flipy)

+puticn(Ppu *p, Layer *layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint8 flipx, Uint8 flipy)

 {

 	Uint16 v, h;

 	for(v = 0; v < 8; v++)

@@ -94,7 +89,7 @@ puticn(Ppu *p, Uint8 layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint

 }

 void

-putchr(Ppu *p, Uint8 layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint8 flipx, Uint8 flipy)

+putchr(Ppu *p, Layer *layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint8 flipx, Uint8 flipy)

 {

 	Uint16 v, h;

 	for(v = 0; v < 8; v++)

@@ -117,16 +112,16 @@ inspect(Ppu *p, Uint8 *stack, Uint8 ptr)

 	Uint8 i, x, y, b;

 	for(i = 0; i < 0x20; ++i) { /* memory */

 		x = ((i % 8) * 3 + 1) * 8, y = (i / 8 + 1) * 8, b = stack[i];

-		puticn(p, 0, x, y, font[(b >> 4) & 0xf], 1 + (ptr == i) * 0x7, 0, 0);

-		puticn(p, 0, x + 8, y, font[b & 0xf], 1 + (ptr == i) * 0x7, 0, 0);

+		puticn(p, &p->bg, x, y, font[(b >> 4) & 0xf], 1 + (ptr == i) * 0x7, 0, 0);

+		puticn(p, &p->bg, x + 8, y, font[b & 0xf], 1 + (ptr == i) * 0x7, 0, 0);

 	}

 	for(x = 0; x < 0x20; ++x) {

-		putpixel(p, 0, x, p->height / 2, 2);

-		putpixel(p, 0, p->width - x, p->height / 2, 2);

-		putpixel(p, 0, p->width / 2, p->height - x, 2);

-		putpixel(p, 0, p->width / 2, x, 2);

-		putpixel(p, 0, p->width / 2 - 16 + x, p->height / 2, 2);

-		putpixel(p, 0, p->width / 2, p->height / 2 - 16 + x, 2);

+		putpixel(p, &p->bg, x, p->height / 2, 2);

+		putpixel(p, &p->bg, p->width - x, p->height / 2, 2);

+		putpixel(p, &p->bg, p->width / 2, p->height - x, 2);

+		putpixel(p, &p->bg, p->width / 2, x, 2);

+		putpixel(p, &p->bg, p->width / 2 - 16 + x, p->height / 2, 2);

+		putpixel(p, &p->bg, p->width / 2, p->height / 2 - 16 + x, 2);

 	}

 }

@@ -137,9 +132,9 @@ initppu(Ppu *p, Uint8 hor, Uint8 ver)

 	p->ver = ver;

 	p->width = 8 * p->hor;

 	p->height = 8 * p->ver;

-	if(!(p->index = malloc(p->width * p->height / 8 * sizeof(Uint32))))

+	if(!(p->bg.pixels = malloc(p->width * p->height * sizeof(Uint32))))

 		return 0;

-	if(!(p->rgba = malloc(p->width * p->height * sizeof(Uint32))))

+	if(!(p->fg.pixels = malloc(p->width * p->height * sizeof(Uint32))))

 		return 0;

 	clear(p);

 	return 1;

@@ -18,17 +18,17 @@ typedef unsigned short Uint16;

 typedef unsigned int Uint32;

 typedef struct Layer {

-	Uint32 *pixels;

+	Uint32 *pixels, colors[4];

 } Layer;

 typedef struct Ppu {

-	Uint32 *rgba, *index, colors[16];

 	Uint16 hor, ver, width, height;

+	Layer fg, bg;

 } Ppu;

 int initppu(Ppu *p, Uint8 hor, Uint8 ver);

 void putcolors(Ppu *p, Uint8 *addr);

-void putpixel(Ppu *p, Uint8 layer, Uint16 x, Uint16 y, Uint8 color);

-void puticn(Ppu *p, Uint8 layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint8 flipx, Uint8 flipy);

-void putchr(Ppu *p, Uint8 layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint8 flipx, Uint8 flipy);

+void putpixel(Ppu *p, Layer *layer, Uint16 x, Uint16 y, Uint8 color);

+void puticn(Ppu *p, Layer *layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint8 flipx, Uint8 flipy);

+void putchr(Ppu *p, Layer *layer, Uint16 x, Uint16 y, Uint8 *sprite, Uint8 color, Uint8 flipx, Uint8 flipy);

 void inspect(Ppu *p, Uint8 *stack, Uint8 ptr);

@@ -20,7 +20,7 @@ WITH REGARD TO THIS SOFTWARE.

 static SDL_AudioDeviceID audio_id;

 static SDL_Window *gWindow;

 static SDL_Renderer *gRenderer;

-static SDL_Texture *gTexture;

+static SDL_Texture *fgTexture, *bgTexture;

 static SDL_Rect gRect;

 static Ppu ppu;

 static Apu apu[POLYPHONY];

@@ -60,9 +60,11 @@ redraw(Uxn *u)

 {

 	if(debug)

 		inspect(&ppu, u->wst.dat, u->wst.ptr);

-	SDL_UpdateTexture(gTexture, &gRect, ppu.rgba, ppu.width * sizeof(Uint32));

+	SDL_UpdateTexture(bgTexture, &gRect, ppu.bg.pixels, ppu.width * sizeof(Uint32));

+	SDL_UpdateTexture(fgTexture, &gRect, ppu.fg.pixels, ppu.width * sizeof(Uint32));

 	SDL_RenderClear(gRenderer);

-	SDL_RenderCopy(gRenderer, gTexture, NULL, NULL);

+	SDL_RenderCopy(gRenderer, bgTexture, NULL, NULL);

+	SDL_RenderCopy(gRenderer, fgTexture, NULL, NULL);

 	SDL_RenderPresent(gRenderer);

 	reqdraw = 0;

 }

@@ -85,11 +87,13 @@ togglezoom(Uxn *u)

 void

 quit(void)

 {

-	free(ppu.rgba);

-	free(ppu.index);

+	free(ppu.fg.pixels);

+	free(ppu.bg.pixels);

 	SDL_UnlockAudioDevice(audio_id);

-	SDL_DestroyTexture(gTexture);

-	gTexture = NULL;

+	SDL_DestroyTexture(bgTexture);

+	bgTexture = NULL;

+	SDL_DestroyTexture(fgTexture);

+	fgTexture = NULL;

 	SDL_DestroyRenderer(gRenderer);

 	gRenderer = NULL;

 	SDL_DestroyWindow(gWindow);

@@ -119,10 +123,14 @@ init(void)

 	if(gRenderer == NULL)

 		return error("Renderer", SDL_GetError());

 	SDL_RenderSetLogicalSize(gRenderer, ppu.width + PAD * 2, ppu.height + PAD * 2);

-	gTexture = SDL_CreateTexture(gRenderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STATIC, ppu.width + PAD * 2, ppu.height + PAD * 2);

-	if(gTexture == NULL)

+	bgTexture = SDL_CreateTexture(gRenderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STATIC, ppu.width + PAD * 2, ppu.height + PAD * 2);

+	if(bgTexture == NULL || SDL_SetTextureBlendMode(bgTexture, SDL_BLENDMODE_NONE))

 		return error("Texture", SDL_GetError());

-	SDL_UpdateTexture(gTexture, NULL, ppu.rgba, 4);

+	fgTexture = SDL_CreateTexture(gRenderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STATIC, ppu.width + PAD * 2, ppu.height + PAD * 2);

+	if(fgTexture == NULL || SDL_SetTextureBlendMode(fgTexture, SDL_BLENDMODE_BLEND))

+		return error("Texture", SDL_GetError());

+	SDL_UpdateTexture(bgTexture, NULL, ppu.bg.pixels, 4);

+	SDL_UpdateTexture(fgTexture, NULL, ppu.fg.pixels, 4);

 	SDL_StartTextInput();

 	SDL_ShowCursor(SDL_DISABLE);

 	SDL_zero(as);

@@ -224,7 +232,7 @@ screen_talk(Device *d, Uint8 b0, Uint8 w)

 		Uint16 x = mempeek16(d->dat, 0x8);

 		Uint16 y = mempeek16(d->dat, 0xa);

 		Uint8 *addr = &d->mem[mempeek16(d->dat, 0xc)];

-		Uint8 layer = (d->dat[0xe] >> 4) & 0x1;

+		Layer *layer = d->dat[0xe] >> 4 & 0x1 ? &ppu.fg : &ppu.bg;

 		Uint8 mode = d->dat[0xe] >> 5;

 		if(!mode)

 			putpixel(&ppu, layer, x, y, d->dat[0xe] & 0x3);