2xsaiwin.cpp

著名SFC模拟器Snes9x的源代码。

        uint32 Nextline = srcPitch >> 1;

        for (height; height; height-=1)
	{
	    bP = (uint16 *) srcPtr;
	    dP = (uint32 *) dstPtr;
            for (uint32 finish = width; finish; finish -= 1 )
            {

           	uint32 color4, color5, color6;
           	uint32 color1, color2, color3;
           	uint32 colorA0, colorA1, colorA2, colorA3,
                  colorB0, colorB1, colorB2, colorB3,
                  colorS1, colorS2;
           	uint32 product1a, product1b,
                  product2a, product2b;

            	colorB0 = *(bP- Nextline - 1);
            	colorB1 = *(bP- Nextline);
            	colorB2 = *(bP- Nextline + 1);
            	colorB3 = *(bP- Nextline + 2);

            	color4 = *(bP - 1);
            	color5 = *(bP);
            	color6 = *(bP + 1);
            	colorS2 = *(bP + 2);

            	color1 = *(bP + Nextline - 1);
            	color2 = *(bP + Nextline);
            	color3 = *(bP + Nextline + 1);
            	colorS1 = *(bP + Nextline + 2);

            	colorA0 = *(bP + Nextline + Nextline - 1);
            	colorA1 = *(bP + Nextline + Nextline);
            	colorA2 = *(bP + Nextline + Nextline + 1);
            	colorA3 = *(bP + Nextline + Nextline + 2);


                //--------------------------------------
                if (color2 == color6 && color5 != color3)
                {
                   product1b = product2a = color2;
                   if ((color1 == color2 && color6 == colorS2) ||
                       (color2 == colorA1 && color6 == colorB2))
                   {
                       product1a = INTERPOLATE (color2, color5);
                       product1a = INTERPOLATE (color2, product1a);
                       product2b = INTERPOLATE (color2, color3);
                       product2b = INTERPOLATE (color2, product2b);
//                       product1a = color2;
//                       product2b = color2;
                   }
                   else
                   {
                      product1a = INTERPOLATE (color5, color6);
                      product2b = INTERPOLATE (color2, color3);
                   }
                }
                else
                if (color5 == color3 && color2 != color6)
                {
                   product2b = product1a = color5;
                   if ((colorB1 == color5 && color3 == colorA2) ||
                       (color4 == color5 && color3 == colorS1))
                   {
                       product1b = INTERPOLATE (color5, color6);
                       product1b = INTERPOLATE (color5, product1b);
                       product2a = INTERPOLATE (color5, color2);
                       product2a = INTERPOLATE (color5, product2a);
//                       product1b = color5;
//                       product2a = color5;
                   }
                   else
                   {
                      product1b = INTERPOLATE (color5, color6);
                      product2a = INTERPOLATE (color2, color3);
                   }
                }
                else
                if (color5 == color3 && color2 == color6 && color5 != color6)
                {
                   register int r = 0;

                   r += GetResult (color6, color5, color1, colorA1);
                   r += GetResult (color6, color5, color4, colorB1);
                   r += GetResult (color6, color5, colorA2, colorS1);
                   r += GetResult (color6, color5, colorB2, colorS2);

                   if (r > 0)
                   {
                      product1b = product2a = color2;
                      product1a = product2b = INTERPOLATE (color5, color6);
                   }
                   else
                   if (r < 0)
                   {
                      product2b = product1a = color5;
                      product1b = product2a = INTERPOLATE (color5, color6);
                   }
                   else
                   {
                      product2b = product1a = color5;
                      product1b = product2a = color2;
                   }
                }
                else
                {

                   if ((color2 == color5) || (color3 == color6))
                   {
                      product1a = color5;
                      product2a = color2;
                      product1b = color6;
                      product2b = color3;

                   }
                   else
                   {
                      product1b = product1a = INTERPOLATE (color5, color6);
                      product1a = INTERPOLATE (color5, product1a);
                      product1b = INTERPOLATE (color6, product1b);

                      product2a = product2b = INTERPOLATE (color2, color3);
                      product2a = INTERPOLATE (color2, product2a);
                      product2b = INTERPOLATE (color3, product2b);
                   }
                }


            	product1a = product1a | (product1b << 16);
            	product2a = product2a | (product2b << 16);

		*(dP) = product1a;
		*(dP+(dstPitch>>2)) = product2a;

                bP += 1;
                dP += 1;
            }//end of for ( finish= width etc..)

	    dstPtr += dstPitch << 1;
            srcPtr += srcPitch;
            deltaPtr += srcPitch;
	}; //endof: for (height; height; height--)
#ifdef MMX
    }
#endif
}



/*ONLY use with 640x480x16 or higher resolutions*/
/*Only use this if 2*width * 2*height fits on the current screen*/
void _2xSaI(uint8 *srcPtr, uint32 srcPitch,
	     uint8 *deltaPtr,
	     uint8 *dstPtr, uint32 dstPitch, int width, int height)
{
    uint32 *dP;
    uint16 *bP;
    uint16 *xP;

#ifdef MMX
    if (mmx_cpu && width != 512)
    {
	for (height; height; height-=1)
	{

	    bP = (uint16 *) srcPtr;
	    xP = (uint16 *) deltaPtr;
	    dP = (uint32 *) dstPtr;
            _2xSaILine  ((uint8 *) bP, (uint8 *) xP, srcPitch, width, (uint8 *)dP, dstPitch);
	    dstPtr += dstPitch << 1;
	    srcPtr += srcPitch;
            deltaPtr += srcPitch;
        }
    }
    else
    {
#endif
        uint32 Nextline = srcPitch >> 1;

        for (height; height; height-=1)
	{
	    bP = (uint16 *) srcPtr;
	    dP = (uint32 *) dstPtr;
            for (uint32 finish = width; finish; finish -= 1 )
            {


                register uint32 colorA, colorB;
                uint32 colorC, colorD,
                       colorE, colorF, colorG, colorH,
                       colorI, colorJ, colorK, colorL,
                       colorM, colorN, colorO, colorP;
                uint32 product, product1, product2;


//---------------------------------------
// Map of the pixels:                    I|E F|J
//                                       G|A B|K
//                                       H|C D|L
//                                       M|N O|P
                colorI = *(bP- Nextline - 1);
                colorE = *(bP- Nextline);
                colorF = *(bP- Nextline + 1);
                colorJ = *(bP- Nextline + 2);

                colorG = *(bP - 1);
                colorA = *(bP);
                colorB = *(bP + 1);
                colorK = *(bP + 2);

                colorH = *(bP + Nextline - 1);
                colorC = *(bP + Nextline);
                colorD = *(bP + Nextline + 1);
                colorL = *(bP + Nextline + 2);

                colorM = *(bP + Nextline + Nextline - 1);
                colorN = *(bP + Nextline + Nextline);
                colorO = *(bP + Nextline + Nextline + 1);
                colorP = *(bP + Nextline + Nextline + 2);

                        if ((colorA == colorD) && (colorB != colorC))
                        {
                           if ( ((colorA == colorE) && (colorB == colorL)) ||
                                ((colorA == colorC) && (colorA == colorF) && (colorB != colorE) && (colorB == colorJ)) )
                           {
                              product = colorA;
                           }
                           else
                           {
                              product = INTERPOLATE(colorA, colorB);
                           }

                           if (((colorA == colorG) && (colorC == colorO)) ||
                               ((colorA == colorB) && (colorA == colorH) && (colorG != colorC) && (colorC == colorM)) )
                           {
                              product1 = colorA;
                           }
                           else
                           {
                              product1 = INTERPOLATE(colorA, colorC);
                           }
                           product2 = colorA;
                        }
                        else
                        if ((colorB == colorC) && (colorA != colorD))
                        {
                           if (((colorB == colorF) && (colorA == colorH)) ||
                               ((colorB == colorE) && (colorB == colorD) && (colorA != colorF) && (colorA == colorI)) )
                           {
                              product = colorB;
                           }
                           else
                           {
                              product = INTERPOLATE(colorA, colorB);
                           }

                           if (((colorC == colorH) && (colorA == colorF)) ||
                               ((colorC == colorG) && (colorC == colorD) && (colorA != colorH) && (colorA == colorI)) )
                           {
                              product1 = colorC;
                           }
                           else
                           {
                              product1 = INTERPOLATE(colorA, colorC);
                           }
                           product2 = colorB;
                        }
                        else
                        if ((colorA == colorD) && (colorB == colorC))
                        {
                           if (colorA == colorB)
                           {
                              product = colorA;
                              product1 = colorA;
                              product2 = colorA;
                           }
                           else
                           {
                              register int r = 0;
                              product1 = INTERPOLATE(colorA, colorC);
                              product = INTERPOLATE(colorA, colorB);

                              r += GetResult1 (colorA, colorB, colorG, colorE, colorI);
                              r += GetResult2 (colorB, colorA, colorK, colorF, colorJ);
                              r += GetResult2 (colorB, colorA, colorH, colorN, colorM);
                              r += GetResult1 (colorA, colorB, colorL, colorO, colorP);

                              if (r > 0)
                                  product2 = colorA;
                              else
                              if (r < 0)
                                  product2 = colorB;
                              else
                              {
                                  product2 = Q_INTERPOLATE(colorA, colorB, colorC, colorD);
                              }
                           }
                        }
                        else
                        {
                           product2 = Q_INTERPOLATE(colorA, colorB, colorC, colorD);

                           if ((colorA == colorC) && (colorA == colorF) && (colorB != colorE) && (colorB == colorJ))
                           {
                              product = colorA;
                           }
                           else
                           if ((colorB == colorE) && (colorB == colorD) && (colorA != colorF) && (colorA == colorI))
                           {
                              product = colorB;
                           }
                           else
                           {
                              product = INTERPOLATE(colorA, colorB);
                           }

                           if ((colorA == colorB) && (colorA == colorH) && (colorG != colorC) && (colorC == colorM))
                           {
                              product1 = colorA;
                           }
                           else
                           if ((colorC == colorG) && (colorC == colorD) && (colorA != colorH) && (colorA == colorI))
                           {
                              product1 = colorC;
                           }
                           else
                           {
                              product1 = INTERPOLATE(colorA, colorC);
                           }
                        }
                        product = colorA | (product << 16);
                        product1 = product1 | (product2 << 16);
			*(dP) = product;
			*(dP+(dstPitch>>2)) = product1;

                    bP += 1;
                    dP += 1;
                }//end of for ( finish= width etc..)

	    dstPtr += dstPitch << 1;
            srcPtr += srcPitch;
            deltaPtr += srcPitch;
	}; //endof: for (height; height; height--)
#ifdef MMX
    }
#endif
}