light: add _surface_minlight_scale light key

for tweaking minlight given to faces matching surface light templates.

minlight = _surface_minlight_scale * light

lower default from 64 to 1 in q1 mode

include/light/entities.hh

@@ -99,6 +99,7 @@ public:
     settings::setting_string suntexture;
     settings::setting_bool nostaticlight;
     settings::setting_int32 surflight_group;
+    settings::setting_scalar surface_minlight_scale;
     settings::setting_int32 light_channel_mask;
     settings::setting_int32 shadow_channel_mask;
     settings::setting_bool nonudge;

include/light/surflight.hh

@@ -49,8 +49,10 @@ struct surfacelight_t
     bool rescale;
 };
 
+class light_t;
+
 void ResetSurflight();
 std::vector<surfacelight_t> &GetSurfaceLights();
-std::optional<std::tuple<int32_t, int32_t, qvec3d>> IsSurfaceLitFace(const mbsp_t *bsp, const mface_t *face);
+std::optional<std::tuple<int32_t, int32_t, qvec3d, light_t *>> IsSurfaceLitFace(const mbsp_t *bsp, const mface_t *face);
 const std::vector<int> &SurfaceLightsForFaceNum(int facenum);
 void MakeRadiositySurfaceLights(const settings::worldspawn_keys &cfg, const mbsp_t *bsp);

light/entities.cc

@@ -106,6 +106,7 @@ light_t::light_t() :
     suntexture{this, "suntexture", ""},
     nostaticlight{this, "nostaticlight", false},
     surflight_group{this, "surflight_group", 0},
+    surface_minlight_scale{this, "surface_minlight_scale", 64},
     light_channel_mask{this, "light_channel_mask", CHANNEL_MASK_DEFAULT},
     shadow_channel_mask{this, "shadow_channel_mask", CHANNEL_MASK_DEFAULT},
     nonudge{this, "nonudge", false}
@@ -262,7 +263,7 @@ static void SetupSpotlights(const settings::worldspawn_keys &cfg)
     }
 }
 
-static void CheckEntityFields(const settings::worldspawn_keys &cfg, light_t *entity)
+static void CheckEntityFields(const mbsp_t *bsp, const settings::worldspawn_keys &cfg, light_t *entity)
 {
     if (entity->light.value() == 0.0f)
         entity->light.setValue(DEFAULTLIGHTLEVEL, settings::source::MAP);
@@ -303,6 +304,13 @@ static void CheckEntityFields(const settings::worldspawn_keys &cfg, light_t *ent
         entity->shadow_channel_mask.setValue(entity->light_channel_mask.value(),
             settings::source::DEFAULT);
     }
+
+    if (!entity->surface_minlight_scale.isChanged()) {
+        if (bsp->loadversion->game->id != GAME_QUAKE_II) {
+            // TODO: also use 1.0 for Q2?
+            entity->surface_minlight_scale.setValue(1.0, settings::source::DEFAULT);
+        }
+    }
 }
 
 /*
@@ -987,7 +995,7 @@ void LoadEntities(const settings::worldspawn_keys &cfg, const mbsp_t *bsp)
                         entity->projfov.value(), entity->projectionmatrix);
             }
 
-            CheckEntityFields(cfg, entity.get());
+            CheckEntityFields(bsp, cfg, entity.get());
         }
     }
 

light/ltface.cc

@@ -3015,7 +3015,9 @@ void DirectLightFace(const mbsp_t *bsp, lightsurf_t &lightsurf, const settings::
         }
 
         if (auto value = IsSurfaceLitFace(bsp, face)) {
-            minlight = std::get<0>(value.value()) * 64.0f;
+            auto *entity = std::get<3>(value.value());
+            const float surface_minlight_scale = entity ? entity->surface_minlight_scale.value() : 64.0f;
+            minlight = std::get<0>(value.value()) * surface_minlight_scale;
             minlight_color = std::get<2>(value.value());
             LightFace_Min(bsp, face, minlight_color, minlight, &lightsurf, lightmaps, std::get<1>(value.value()));
         }

light/surflight.cc

@@ -147,20 +147,20 @@ static void MakeSurfaceLight(const mbsp_t *bsp, const settings::worldspawn_keys
     surfacelightsByFacenum[Face_GetNum(bsp, face)].push_back(index);
 }
 
-std::optional<std::tuple<int32_t, int32_t, qvec3d>> IsSurfaceLitFace(const mbsp_t *bsp, const mface_t *face)
+std::optional<std::tuple<int32_t, int32_t, qvec3d, light_t *>> IsSurfaceLitFace(const mbsp_t *bsp, const mface_t *face)
 {
     if (bsp->loadversion->game->id == GAME_QUAKE_II) {
         // first, check if it's a Q2 surface
         const mtexinfo_t *info = Face_Texinfo(bsp, face);
 
         if (info != nullptr && (info->flags.native & Q2_SURF_LIGHT) && info->value > 0) {
-            return std::make_tuple(info->value, 0, qvec3d(Face_LookupTextureColor(bsp, face)));
+            return std::make_tuple(info->value, 0, qvec3d(Face_LookupTextureColor(bsp, face)), nullptr);
         }
     }
 
     for (const auto &surflight : GetSurfaceLightTemplates()) {
         if (FaceMatchesSurfaceLightTemplate(bsp, face, ModelInfoForFace(bsp, face - bsp->dfaces.data()), *surflight, SURFLIGHT_RAD)) {
-            return std::make_tuple(surflight->light.value(), surflight->style.value(), surflight->color.isChanged() ? surflight->color.value() : qvec3d(Face_LookupTextureColor(bsp, face)));
+            return std::make_tuple(surflight->light.value(), surflight->style.value(), surflight->color.isChanged() ? surflight->color.value() : qvec3d(Face_LookupTextureColor(bsp, face)), surflight.get());
         }
     }
 

testmaps/q1_surflight_minlight.map

@@ -68,24 +68,43 @@
 ( -3072 -1360 -576 ) ( -3071 -1360 -576 ) ( -3072 -1360 -575 ) bolt3 [ 1 0 0 0 ] [ 0 0 -1 0 ] 0 1 1
 ( -3072 -1360 -576 ) ( -3072 -1360 -575 ) ( -3072 -1359 -576 ) bolt3 [ 0 1 0 0 ] [ 0 0 -1 0 ] 0 1 1
 }
+// brush 7
+{
+( -3264 -1440 -528 ) ( -3264 -1472 -528 ) ( -3264 -1472 -592 ) *zwater1 [ 0 1 0 -32 ] [ 0 0 -1 -16 ] 0 1 1
+( -3264 -1472 -528 ) ( -3256 -1472 -528 ) ( -3256 -1472 -592 ) *zwater1 [ 1 0 0 0 ] [ 0 0 -1 0 ] 0 1 1
+( -3256 -1472 -592 ) ( -3256 -1440 -592 ) ( -3264 -1440 -592 ) *zwater1 [ 1 0 0 0 ] [ 0 -1 0 16 ] 0 1 1
+( -3264 -1440 -528 ) ( -3256 -1440 -528 ) ( -3256 -1472 -528 ) *zwater1 [ 1 0 0 0 ] [ 0 -1 0 16 ] 0 1 1
+( -3256 -1440 -592 ) ( -3256 -1440 -528 ) ( -3264 -1440 -528 ) *zwater1 [ 1 0 0 0 ] [ 0 0 -1 0 ] 0 1 1
+( -3256 -1472 -528 ) ( -3256 -1440 -528 ) ( -3256 -1440 -592 ) *zwater1 [ 0 1 0 -16 ] [ 0 0 -1 0 ] 0 1 1
+}
 }
 // entity 1
 {
-"classname" "light"
-"origin" "-3112 -1776 -680"
-"_surface" "light"
-"light" "300"
-"_color" "250 220 210"
-"_surface_radiosity " "1"
-"_nofill" "1"
-}
-// entity 2
-{
 "classname" "info_player_start"
 "origin" "-3504 -1680 -568"
 }
-// entity 3
+// entity 2
 {
 "classname" "info_null"
 "origin" "-3376 -1640 -488"
 }
+// entity 3
+{
+"classname" "light"
+"origin" "-3112 -1776 -680"
+"_surface" "light"
+"light" "100"
+"_color" "255 127.5 0"
+"_surface_radiosity " "1"
+"_nofill" "1"
+}
+// entity 4
+{
+"classname" "light"
+"origin" "-3112 -1680 -680"
+"_surface" "*zwater1"
+"light" "100"
+"_color" "255 127.5 0"
+"_surface_radiosity " "1"
+"_nofill" "1"
+}

tests/test_ltface.cc

@@ -454,7 +454,24 @@ TEST_CASE("surface lights minlight" * doctest::may_fail()) {
     auto *surflight = BSP_FindFaceAtPoint(&bsp, &bsp.dmodels[0], {-3264, -1664, -560});
     REQUIRE(surflight);
 
-    CheckFaceLuxels(bsp, *surflight, [](qvec3b sample) {
+    const auto l = [](qvec3b sample) {
-        CHECK(sample == qvec3b(255, 224, 214));
+        // "light" key is 100, color is (1, 0.5, 0), but values get halved due to overbright
-    }, &lit);
+
+        CHECK(sample[0] <= 75);
+        CHECK(sample[0] >= 50);
+
+        CHECK(sample[1] <= 35);
+        CHECK(sample[1] >= 25);
+
+        CHECK(sample[2] == 0);
+    };
+
+    CheckFaceLuxels(bsp, *surflight, l, &lit);
+
+    INFO("same but with liquid");
+
+    auto *liquid_face = BSP_FindFaceAtPoint(&bsp, &bsp.dmodels[0], {-3264, -1456, -560}, {-1,0,0});
+    REQUIRE(liquid_face);
+
+    CheckFaceLuxels(bsp, *liquid_face, l, &lit);
 }