light: Add support for LIGHTING_E5BGR9.

This is not really finished. Currently mutually exclusive with
regular RGBLIGHTING, and not tested with external .lit file.

include/light/light.hh

@@ -171,7 +171,8 @@ enum class lightfile
     external = 1,
     bspx = 2,
     both = external | bspx,
-    lit2 = 4
+    lit2 = 4,
+    hdr = 8,
 };
 
 /* tracelist is a std::vector of pointers to modelinfo_t to use for LOS tests */
@@ -393,6 +394,8 @@ public:
     setting_func bspxlux;
     setting_func bspxonly;
     setting_func bspx;
+    setting_func hdr;
+    setting_func bspxhdr;
     setting_scalar world_units_per_luxel;
     setting_bool litonly;
     setting_bool nolights;

include/light/write.hh

@@ -67,7 +67,7 @@ struct facesup_t
     twosided<uint16_t> extent;
 };
 
-void WriteLitFile(const mbsp_t *bsp, const std::vector<facesup_t> &facesup, const fs::path &filename, int version, const std::vector<uint8_t> &lit_filebase, const std::vector<uint8_t> &lux_filebase);
+void WriteLitFile(const mbsp_t *bsp, const std::vector<facesup_t> &facesup, const fs::path &filename, int version, const std::vector<uint8_t> &lit_filebase, const std::vector<uint8_t> &lux_filebase, const std::vector<uint8_t> &hdr_filebase);
 void WriteLuxFile(const mbsp_t *bsp, const fs::path &filename, int version, const std::vector<uint8_t> &lux_filebase);
 
 void SaveLightmapSurfaces(bspdata_t *bspdata, const fs::path &source);

light/light.cc

@@ -320,6 +320,9 @@ light_settings::light_settings()
       lux{this, "lux", [&](source) { write_luxfile |= lightfile::external; }, &experimental_group, "write .lux file"},
       bspxlux{this, "bspxlux", [&](source) { write_luxfile |= lightfile::bspx; }, &experimental_group,
           "writes lux data into the bsp itself"},
+      hdr{this, "hdr", [&](source) { write_litfile |= lightfile::external; write_litfile |= lightfile::hdr; }, &experimental_group, "write .lit file with e5bgr9 data"},
+      bspxhdr{this, "bspxhdr", [&](source) { write_litfile |= lightfile::bspx; write_litfile |= lightfile::hdr; }, &experimental_group,
+          "writes lux data into the bsp itself"},
       bspxonly{this, "bspxonly",
           [&](source source) {
               write_litfile = lightfile::bspx;

light/ltface.cc

@@ -2453,14 +2453,6 @@ static void LightPoint_ScaleAndClamp(qvec3f &color)
             c = pow(c / 255.0f, 1.0f / cfg.lightmapgamma.value()) * 255.0f;
         }
     }
-
-    // clamp
-    // FIXME: should this be a brightness clamp?
-    float maxcolor = qv::max(color);
-
-    if (maxcolor > 255.0f) {
-        color *= (255.0f / maxcolor);
-    }
 }
 
 static void LightPoint_ScaleAndClamp(lightgrid_samples_t &result)