shithub: qk1

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fog: don't recalculate the same thing; no possible additive blending so inline it

--- a/r_fog.c

+++ b/r_fog.c

@@ -43,7 +43,7 @@

 void

 R_DrawFog(void)

 {

-	byte skyfogalpha, a;

+	byte ca0, ca1, ca2, skyfogalpha, a;

 	pixel_t *pix;

 	int i, x, y;

 	uzint *z;

@@ -52,6 +52,10 @@

 	if(r_fog.density <= 0.0)

 		return;

+	ca0 = r_fog.color>> 0;

+	ca1 = r_fog.color>> 8;

+	ca2 = r_fog.color>>16;

+

 	skyfogalpha = 255 * clamp(r_skyfog.value, 0, 1.0);

 	/* FIXME(sigrid): this is super slow */

 	for(y = r_refdef.vrect.y; y < r_refdef.vrectbottom; y++){

@@ -59,17 +63,21 @@

 		pix = vid.buffer + i;

 		z = d_pzbuffer + i;

 		for(x = r_refdef.vrect.x; x < r_refdef.vrectright; x++, i++, pix++, z++){

-			if(*z >= 65536){

+			if(*z > 65536){

 				d = 65536.0 / (float)(*z >> 16);

 				d = 1.0 - exp2(-r_fog.density * d*d);

-				a = 255 * clamp(d, 0.0, 1.0);

+				a = 255*clamp(d, 0.0, 1.0);

 			}else if(*z < 0){

 				a = skyfogalpha;

 			}else

 				continue;

-			if(a > 0)

-				*pix = blendalpha(r_fog.color, *pix, a);

+			if(a > 0){

+				*pix =

+					((a*ca0 + (255-a)*((*pix>> 0)&0xff)) >> 8) << 0 |

+					((a*ca1 + (255-a)*((*pix>> 8)&0xff)) >> 8) << 8 |

+					((a*ca2 + (255-a)*((*pix>>16)&0xff)) >> 8) << 16;

+			}

 		}

 	}

 }