@@ -61,6 +61,7 @@
 bool CBitmapManager::bAlpha = true;
 BYTE CBitmapManager::eyeCandy = 1;
 float CBitmapManager::fLightLevel = 1.0f;
+Uint8 shadow[256][256];

 Uint8 CBitmapManager::TransColor[3] = {192,192,192};   //(r,g,b) color that signifies transparent pixels: default=192-gray

@@ -96,6 +97,15 @@
 #ifdef GAME_RENDERING_OFFSET
        ASSERT(CBitmapManager::BYTES_PER_PIXEL == 4);
 #endif
+       float fPercent = 1.0f;
+       for (int i = 0; i <= 255; i++)
+               {
+                       fPercent = 1.0f - ((255 - i) * fShadowConvFactor);
+                       for (int j = 0; j <= 255; j++)
+                       {
+                               shadow[i][j] = static_cast<Uint8>(j * fPercent);
+                       }
+               }
 }

 //**********************************************************************************
@@ -2350,10 +2360,10 @@
                                        //Darken by amount of shadow source image.
                                        //It is not assumed that a substantial amount of this image has
                                        //values of 0 or 255, so we won't waste CPU checking for them.
-                                       fPercent = 1.0f - ((255 - pSrc[0]) * fShadowConvFactor); //examine only first color value
-                                       pDest[0] = static_cast<Uint8>(pDest[0] * fPercent);
-                                       pDest[1] = static_cast<Uint8>(pDest[1] * fPercent);
-                                       pDest[2] = static_cast<Uint8>(pDest[2] * fPercent);
+
+                                       pDest[0] = shadow[pSrc[0]][pDest[0]];
+                                       pDest[1] = shadow[pSrc[0]][pDest[1]];
+                                       pDest[2] = shadow[pSrc[0]][pDest[2]];

                                        pSrc += wSrcBPP;
                                        pDest += wBPP;

in vars:
	Uint8 darken[20][256];

in init:
	for (int z = 0; z <= 19; z++)
	    {
	        fPercent = 0.05f * z;
	        for (int j = 0; j <= 255; j++)
	        {
	            darken[z][j] = static_cast<Uint8>(j * fPercent);
	        }
	    }

then replace whole section from
if (fLightPercent == 0.0f)
to
if (SDL_MUSTLOCK(pDestSurface))
(could maybe keep those 0/0.5 cases as is)


with

	Uint8 const dark = fLightPercent / 0.05f;
	Uint8 *const pDarken = darken[dark];
	while (pSeek != pStop)
	{
	    ASSERT(pSeek < pStop);
	    Uint8 *const pEndOfRow = pSeek + dwRowWidth;

	    while (pSeek != pEndOfRow)
	    {
	        pSeek[0] = pDarken[pSeek[0]];
	        pSeek[1] = pDarken[pSeek[1]];
	        pSeek[2] = pDarken[pSeek[2]];
	        pSeek += wBPP;
	    }
	    pSeek += dwRowOffset;
	}