Function DrawNameTable

src/drivers/Qt/NameTableViewer.cpp:1672–1753

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}
//----------------------------------------------------
static void DrawNameTable(int scanline, int ntnum, bool invalidateCache) 
{
	NTCache &c = cache[ntnum];
	uint8_t *tablecache = c.cache;

	uint8_t *table = vnapage[ntnum];
	if (table == NULL)
	{
		table = vnapage[ntnum&1];
	}

	int a, ptable=0;
	
	if (PPU[0]&0x10){ //use the correct pattern table based on this bit
		ptable=0x1000;
	}

	bool invalid = invalidateCache;
	//if we werent asked to invalidate the cache, maybe we need to invalidate it anyway due to vnapage changing
	if (!invalid)
	{
		invalid = (c.curr_vnapage != vnapage[ntnum]);
	}
	c.curr_vnapage = vnapage[ntnum];
	
	//HACK: never cache anything
	invalid = true;

	for (int y=0;y<30;y++)
	{
		for (int x=0;x<32;x++)
		{
			int ntaddr = (y*32)+x;
			int attraddr = 0x3C0+((y>>2)<<3)+(x>>2);
			if (invalid
				|| (table[ntaddr] != tablecache[ntaddr]) 
				|| (table[attraddr] != tablecache[attraddr])) 
			{
				int temp = (((y&2)<<1)+(x&2));
				a = (table[attraddr] & (3<<temp)) >> temp;
				
				//the commented out code below is all allegedly equivalent to the single line above:
				//tmpx = x>>2;
				//tmpy = y>>2;
				//a = 0x3C0+(tmpy*8)+tmpx;
				//if((((x>>1)&1) == 0) && (((y>>1)&1) == 0)) a = table[a]&0x3;
				//if((((x>>1)&1) == 1) && (((y>>1)&1) == 0)) a = (table[a]&0xC)>>2;
				//if((((x>>1)&1) == 0) && (((y>>1)&1) == 1)) a = (table[a]&0x30)>>4;
				//if((((x>>1)&1) == 1) && (((y>>1)&1) == 1)) a = (table[a]&0xC0)>>6;

				int chr = table[ntaddr]*16;

				//test.. instead of pretending that the nametable is a screen at 0,0 we pretend that it is at the current xscroll and yscroll
				//int xpos = ((RefreshAddr & 0x400) >> 2) | ((RefreshAddr & 0x1F) << 3) | XOffset;
				//int ypos = ((RefreshAddr & 0x3E0) >> 2) | ((RefreshAddr & 0x7000) >> 12); 
				//if(RefreshAddr & 0x800) ypos += 240;
				//int refreshaddr = (xpos/8+x)+(ypos/8+y)*32;