nesppu.pas

delphi编制的nes模拟器－－tNes

    begin

          //aOffset:=i*4;
        Attr := SprRam[i + 2];
        if (Attr and $20) = 0 then
        begin
            x := SprRam[i + 3];
            y := SprRam[i];
			TileNo := SprRam[i + 1];
			DrawASprite(TileNo, x, y, Attr);


			CopyBmpT(FSCanvas,x,y+1,SprCanvas,ppu_mem[$3f10]);
		  {	if TileNo=$1e then begin
				SprCanvas.SaveToFile('d:\1e.bmp');
				FSCanvas.SaveToFile('d:\1e1.bmp');
			end;   }
		end;


		dec(i, 4);
	   //	FSCanvas.SaveToFile('d:\1e1.bmp');
	end;


end;

procedure TPPU.Reset;
begin
    ZeroMemory(@ppu_mem, $10000);
	ZeroMemory(@SprRam, 256);
	ZeroMemory(@registers,32);
end;

procedure TPPU.DrawASprite(Tiles, x, y, Attr: Byte);
var
	ptAddr: Word;
	i: integer;
	b0, b1: byte;
	P: PByteArray;
	H16:Boolean;
begin
	if (registers[0] and $20) = 0 then
	begin //8x8 piexls
		if (registers[0] and $8) = $8 then
			ptAddr := $1000
		else ptAddr := 0;
		H16:=False;
		SprCanvas.Height:=8;
	end else //8x16 piexls
		begin
			if (Tiles mod 2)=0 then
			//if (registers[0] and 1) = 0 then
				ptAddr := 0
			else	begin
						ptAddr := $1000;
						Dec(Tiles);
					end;

			H16:=true;
			SprCanvas.Height:=16;
		end;



	i := 0;
	case (attr shr 6) of
		0: begin
				while i < 8 do
				begin
					b0 := ppu_mem[ptAddr + tiles * 16 + i];
					b1 := ppu_mem[ptAddr + tiles * 16 + i + 8];

					RenderSpritePixels(b0, b1, attr, i);

					p := SprCanvas.ScanLine[i];


					CopyMemory(p, @Line8, 8);


					if H16 then begin
						//----8x16 sprite;
						b0 := ppu_mem[ptAddr + (tiles + 1)*16 + i];
						b1 := ppu_mem[ptAddr + (tiles + 1)*16 + i + 8];

						RenderSpritePixels(b0, b1, attr, i);

						p := SprCanvas.ScanLine[i+8];


						CopyMemory(p, @Line8, 8);
					end;

					Inc(i);

				end;


			end;
		1: begin //horizontal flip
				while i < 8 do
				begin
					b0 := ppu_mem[ptAddr + tiles * 16 + i];
					b1 := ppu_mem[ptAddr + tiles * 16 + i + 8];

					RenderSpritePixelsHF(b0, b1, attr, i);

					p := SprCanvas.ScanLine[i];


					CopyMemory(p, @Line8, 8);

					if H16 then begin
						//----8x16 sprite;
						b0 := ppu_mem[ptAddr + (tiles + 1)*16 + i];
						b1 := ppu_mem[ptAddr + (tiles + 1)*16 + i + 8];

						RenderSpritePixelsHF(b0, b1, attr, i);

						p := SprCanvas.ScanLine[i+8];


						CopyMemory(p, @Line8, 8);
					end;

					Inc(i);
				end;
			end;

		2: begin //vertical flip
				while i < 8 do
				begin
					b0 := ppu_mem[ptAddr + tiles * 16 + 7 - i];
					b1 := ppu_mem[ptAddr + tiles * 16 + 15 - i];

					RenderSpritePixels(b0, b1, attr, i);

					p := SprCanvas.ScanLine[i];


					CopyMemory(p, @Line8, 8);

					if H16 then begin
						//----8x16 sprite;
						b0 := ppu_mem[ptAddr + (tiles + 1)*16 + 7 -i];
						b1 := ppu_mem[ptAddr + (tiles + 1)*16 + 15 - i ];

						RenderSpritePixels(b0, b1, attr, i);

						p := SprCanvas.ScanLine[i+8];


						CopyMemory(p, @Line8, 8);
					end;

					Inc(i);
				end
			end;

		3: begin // horizontal and vertical flip
				while i < 8 do
				begin
					b0 := ppu_mem[ptAddr + tiles * 16 + 7 - i];
					b1 := ppu_mem[ptAddr + tiles * 16 + 15 - i];

					RenderSpritePixelshf(b0, b1, attr, i);

					p := SprCanvas.ScanLine[i];


					CopyMemory(p, @Line8, 8);

					if H16 then begin
						//----8x16 sprite;
						b0 := ppu_mem[ptAddr + (tiles + 1)*16 + 7 - i];
						b1 := ppu_mem[ptAddr + (tiles + 1)*16 + 15 - i];

						RenderSpritePixels(b0, b1, attr, i);

						p := SprCanvas.ScanLine[i+8];


						CopyMemory(p, @Line8, 8);
					end;

					Inc(i);
				end
		   end;
	end;


end;

procedure TPPU.RenderSpritePixels(b0, b1, attr: Byte; i: integer);
var

    bit00, bit01, bit02, bit03, bit04, bit05, bit06, bit07,
        bit10, bit11, bit12, bit13, bit14, bit15, bit16, bit17,
        low2, Upper2, color_offset, color, at: byte;

begin
	bit00 := b0 and $1;
	bit01 := b0 and $2;
	bit02 := b0 and $4;
	bit03 := b0 and $8;
	bit04 := b0 and $10;
	bit05 := b0 and $20;
	bit06 := b0 and $40;
	bit07 := b0 and $80;

	bit10 := b1 and $1;
	bit11 := b1 and $2;
	bit12 := b1 and $4;
	bit13 := b1 and $8;
	bit14 := b1 and $10;
	bit15 := b1 and $20;
	bit16 := b1 and $40;
	bit17 := b1 and $80;



	upper2 := (Attr and 3) shl 2;
	  //0
	low2 := (bit10 shl 1) or bit00;
	color_offset := low2 or upper2;
	color := ppu_mem[pal[1] + color_offset];

	Line8[7] := color and $3F; //2006.2.9 modifed

   //1
    low2 := bit11 or (bit01 shr 1);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[6] := color and $3F; //2006.2.9 modifed

  //2
    low2 := (bit12 shr 1) or (bit02 shr 2);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[5] := color and $3F; //2006.2.9 modifed

//3
    low2 := (bit13 shr 2) or (bit03 shr 3);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[4] := color and $3F; //2006.2.9 modifed

//4
    low2 := (bit14 shr 3) or (bit04 shr 4);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[3] := color and $3F; //2006.2.9 modifed

//5
    low2 := (bit15 shr 4) or (bit05 shr 5);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[2] := color and $3F; //2006.2.9 modifed

//6
    low2 := (bit16 shr 5) or (bit06 shr 6);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[1] := color and $3F; //2006.2.9 modifed

//7
    low2 := (bit17 shr 6) or (bit07 shr 7);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[0] := color and $3F; //2006.2.9 modifed

end;

procedure TPPU.RenderSpritePixelsHF(b0, b1, attr: Byte; i: Integer);
var

    bit00, bit01, bit02, bit03, bit04, bit05, bit06, bit07,
        bit10, bit11, bit12, bit13, bit14, bit15, bit16, bit17,
        low2, Upper2, color_offset, color, at: byte;

begin
    bit00 := b0 and $1;
    bit01 := b0 and $2;
    bit02 := b0 and $4;
    bit03 := b0 and $8;
    bit04 := b0 and $10;
    bit05 := b0 and $20;
    bit06 := b0 and $40;
    bit07 := b0 and $80;

    bit10 := b1 and $1;
    bit11 := b1 and $2;
    bit12 := b1 and $4;
    bit13 := b1 and $8;
    bit14 := b1 and $10;
    bit15 := b1 and $20;
    bit16 := b1 and $40;
    bit17 := b1 and $80;



    upper2 := (Attr and 3) shl 2;
      //0
    low2 := (bit10 shl 1) or bit00;
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];

    Line8[0] := color and $3F; //2006.2.9 modifed

//1
    low2 := bit11 or (bit01 shr 1);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[1] := color and $3F; //2006.2.9 modifed

//2
    low2 := (bit12 shr 1) or (bit02 shr 2);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[2] := color and $3F; //2006.2.9 modifed
//3
    low2 := (bit13 shr 2) or (bit03 shr 3);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[3] := color and $3F; //2006.2.9 modifed
//4
    low2 := (bit14 shr 3) or (bit04 shr 4);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[4] := color and $3F; //2006.2.9 modifed
//5
    low2 := (bit15 shr 4) or (bit05 shr 5);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[5] := color and $3F; //2006.2.9 modifed
//6
    low2 := (bit16 shr 5) or (bit06 shr 6);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[6] := color and $3F; //2006.2.9 modifed
//7
    low2 := (bit17 shr 6) or (bit07 shr 7);
    color_offset := low2 or upper2;
    color := ppu_mem[pal[1] + color_offset];
    Line8[7] := color and $3F; //2006.2.9 modifed
end;



destructor TPPU.destory;
begin
    BGCanvas.Free;
    BSCanvas.Free;
	FSCanvas.Free;
    SprCanvas.Free;
end;

end.