fix fog, it now matches GL_EXP2 fog as it was meant to (this makes

Nehahra look correct, which it hasn't for years)

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@7777 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/gl_rmain.c b/gl_rmain.c
index 55484014d05da3e5c22f155e076c5b095b15e0c8..b453e2594bd58192ac5d0370d6608d39240cf343 100644 (file)
--- a/gl_rmain.c
+++ b/gl_rmain.c
@@ -384,7 +384,7 @@ static void R_BuildNormalizationCube(void)
 static void R_BuildFogTexture(void)
 {
        int x, b;
-#define FOGWIDTH 64
+#define FOGWIDTH 256
        unsigned char data1[FOGWIDTH][4];
        //unsigned char data2[FOGWIDTH][4];
        for (x = 0;x < FOGWIDTH;x++)
@@ -1825,10 +1825,10 @@ void gl_main_start(void)
        int x;
        double r, alpha;
 
-       r = (-1.0/256.0) * (FOGMASKTABLEWIDTH * FOGMASKTABLEWIDTH);
+       r = -16.0 / (1.0 * FOGMASKTABLEWIDTH * FOGMASKTABLEWIDTH);
        for (x = 0;x < FOGMASKTABLEWIDTH;x++)
        {
-               alpha = 1 - exp(r / ((double)x*(double)x));
+               alpha = exp(r * ((double)x*(double)x));
                if (x == FOGMASKTABLEWIDTH - 1)
                        alpha = 0;
                r_refdef.fogmasktable[x] = bound(0, alpha, 1);
@@ -3277,7 +3277,7 @@ void R_UpdateVariables(void)
                // this is the point where the fog reaches 0.9986 alpha, which we
                // consider a good enough cutoff point for the texture
                // (0.9986 * 256 == 255.6)
-               r_refdef.fogrange = 400 / r_refdef.fog_density;
+               r_refdef.fogrange = 16 / (r_refdef.fog_density * r_refdef.fog_density);
                r_refdef.fograngerecip = 1.0f / r_refdef.fogrange;
                r_refdef.fogmasktabledistmultiplier = FOGMASKTABLEWIDTH * r_refdef.fograngerecip;
                // fog color was already set