fix factors in sRGBlightmaps code

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@11461 d7cf8633-e32d-0410-b094-e92efae38249
::stable-branch::merge=4e5a35dddf8d370d1d65cd86b67a788cb665f872

diff --git a/model_brush.c b/model_brush.c
index f02e3e6a6059dd0753bf6eae077654877fb4db7e..3bec9cdcfff9dcd3b2410e15a6f0daace6a034a0 100644 (file)
--- a/model_brush.c
+++ b/model_brush.c
@@ -4734,10 +4734,13 @@ static void Mod_Q3BSP_LoadVertices(lump_t *l)
                        // working like this may be odd, but matches q3map2 -gamma 2.2
                        if(vid_sRGB.integer && vid_sRGB_fallback.integer && !vid.sRGB3D)
                        {
-                               // TODO (should we do this, or should we instead knowingly render brighter in sRGB fallback mode?)
-                               loadmodel->brushq3.data_color4f[i * 4 + 0] = in->color4ub[0] * (1.0f / 255.0f) * 0.72974f; // fixes neutral level
-                               loadmodel->brushq3.data_color4f[i * 4 + 1] = in->color4ub[1] * (1.0f / 255.0f) * 0.72974f; // fixes neutral level
-                               loadmodel->brushq3.data_color4f[i * 4 + 2] = in->color4ub[2] * (1.0f / 255.0f) * 0.72974f; // fixes neutral level
+                               // actually we do: Image_sRGBFloatFromLinear_Lightmap(Image_LinearFloatFromsRGBFloat(x))
+                               // neutral point is at Image_sRGBFloatFromLinearFloat(0.5)
+                               // so we need to map Image_sRGBFloatFromLinearFloat(0.5) to 0.5
+                               // factor is 0.5 / Image_sRGBFloatFromLinearFloat(0.5)
+                               loadmodel->brushq3.data_color4f[i * 4 + 0] = in->color4ub[0] * (1.0f / 255.0f) * 0.679942f; // fixes neutral level
+                               loadmodel->brushq3.data_color4f[i * 4 + 1] = in->color4ub[1] * (1.0f / 255.0f) * 0.679942f; // fixes neutral level
+                               loadmodel->brushq3.data_color4f[i * 4 + 2] = in->color4ub[2] * (1.0f / 255.0f) * 0.679942f; // fixes neutral level
                        }
                        else
                        {
@@ -5055,9 +5058,13 @@ static void Mod_Q3BSP_LoadLightmaps(lump_t *l, lump_t *faceslump)
                                                int i;
                                                for(i = 0; i < n; i += 4)
                                                {
-                                                       mergedpixels[i+0] = (mergedpixels[i+0] * (int)186 + 128) / 255;
-                                                       mergedpixels[i+1] = (mergedpixels[i+1] * (int)186 + 128) / 255;
-                                                       mergedpixels[i+2] = (mergedpixels[i+2] * (int)186 + 128) / 255;
+                                                       // actually we do: Image_sRGBFloatFromLinear_Lightmap(Image_LinearFloatFromsRGBFloat(x))
+                                                       // neutral point is at Image_sRGBFloatFromLinearFloat(0.5)
+                                                       // so we need to map Image_sRGBFloatFromLinearFloat(0.5) to 0.5
+                                                       // factor is 0.5 / Image_sRGBFloatFromLinearFloat(0.5)
+                                                       mergedpixels[i+0] = (mergedpixels[i+0] * (int)173 + 128) / 255;
+                                                       mergedpixels[i+1] = (mergedpixels[i+1] * (int)173 + 128) / 255;
+                                                       mergedpixels[i+2] = (mergedpixels[i+2] * (int)173 + 128) / 255;
                                                }
                                                t = TEXTYPE_BGRA; // in stupid fallback mode, we upload lightmaps in sRGB form and just fix their brightness
                                        }
@@ -5865,12 +5872,16 @@ static void Mod_Q3BSP_LoadLightGrid(lump_t *l)
                                // TODO (should we do this, or should we instead knowingly render brighter in sRGB fallback mode?)
                                for(i = 0; i < count; ++i)
                                {
-                                       out[i].ambientrgb[0] = (out[i].ambientrgb[0] * (int)186 + 128) / 255; // fixes neutral level
-                                       out[i].ambientrgb[1] = (out[i].ambientrgb[1] * (int)186 + 128) / 255; // fixes neutral level
-                                       out[i].ambientrgb[2] = (out[i].ambientrgb[2] * (int)186 + 128) / 255; // fixes neutral level
-                                       out[i].diffusergb[0] = (out[i].diffusergb[0] * (int)186 + 128) / 255; // fixes neutral level
-                                       out[i].diffusergb[1] = (out[i].diffusergb[1] * (int)186 + 128) / 255; // fixes neutral level
-                                       out[i].diffusergb[2] = (out[i].diffusergb[2] * (int)186 + 128) / 255; // fixes neutral level
+                                       // actually we do: Image_sRGBFloatFromLinear_Lightmap(Image_LinearFloatFromsRGBFloat(x))
+                                       // neutral point is at Image_sRGBFloatFromLinearFloat(0.5)
+                                       // so we need to map Image_sRGBFloatFromLinearFloat(0.5) to 0.5
+                                       // factor is 0.5 / Image_sRGBFloatFromLinearFloat(0.5)
+                                       out[i].ambientrgb[0] = (out[i].ambientrgb[0] * (int)173 + 128) / 255; // fixes neutral level
+                                       out[i].ambientrgb[1] = (out[i].ambientrgb[1] * (int)173 + 128) / 255; // fixes neutral level
+                                       out[i].ambientrgb[2] = (out[i].ambientrgb[2] * (int)173 + 128) / 255; // fixes neutral level
+                                       out[i].diffusergb[0] = (out[i].diffusergb[0] * (int)173 + 128) / 255; // fixes neutral level
+                                       out[i].diffusergb[1] = (out[i].diffusergb[1] * (int)173 + 128) / 255; // fixes neutral level
+                                       out[i].diffusergb[2] = (out[i].diffusergb[2] * (int)173 + 128) / 255; // fixes neutral level
                                }
                        }
                        else