diff --git a/common/bsputils.cc b/common/bsputils.cc
index 1429a7b2..4a7c2a18 100644
--- a/common/bsputils.cc
+++ b/common/bsputils.cc
@@ -1015,10 +1015,15 @@ qvec3f faceextents_t::LMCoordToWorld(qvec2f lm) const
 
 /**
  * Samples the lightmap at an integer coordinate
+ * FIXME: this doesn't deal with styles at all
  */
 qvec3b LM_Sample(const mbsp_t *bsp, const std::vector<uint8_t> *lit, const faceextents_t &faceextents,
     int byte_offset_of_face, qvec2i coord)
 {
+    if (byte_offset_of_face == -1) {
+        return {0, 0, 0};
+    }
+
     Q_assert(coord[0] >= 0);
     Q_assert(coord[1] >= 0);
     Q_assert(coord[0] < faceextents.width());
diff --git a/testmaps/q1_lightignore.map b/testmaps/q1_lightignore.map
new file mode 100644
index 00000000..5be2d41d
--- /dev/null
+++ b/testmaps/q1_lightignore.map
@@ -0,0 +1,100 @@
+// Game: Quake
+// Format: Standard
+// entity 0
+{
+"classname" "worldspawn"
+"wad" "deprecated/free_wad.wad"
+// brush 0
+{
+( -304 32 16 ) ( -304 256 16 ) ( -304 32 192 ) bolt9 0 0 0 1 1
+( -304 32 192 ) ( -288 32 192 ) ( -304 32 16 ) bolt9 0 0 0 1 1
+( -304 32 16 ) ( -288 32 16 ) ( -304 256 16 ) bolt9 0 0 0 1 1
+( -304 256 192 ) ( -288 256 192 ) ( -304 32 192 ) bolt9 0 0 0 1 1
+( -304 256 16 ) ( -288 256 16 ) ( -304 256 192 ) bolt9 0 0 0 1 1
+( -288 32 16 ) ( -288 32 192 ) ( -288 256 16 ) bolt9 0 0 0 1 1
+}
+// brush 1
+{
+( -288 256 192 ) ( -288 240 192 ) ( -288 256 16 ) bolt9 0 0 0 1 1
+( -64 240 192 ) ( -64 240 16 ) ( -288 240 192 ) bolt9 0 0 0 1 1
+( -288 256 16 ) ( -288 240 16 ) ( -64 256 16 ) bolt9 0 0 0 1 1
+( -64 256 192 ) ( -64 240 192 ) ( -288 256 192 ) bolt9 0 0 0 1 1
+( -64 256 192 ) ( -288 256 192 ) ( -64 256 16 ) bolt9 0 0 0 1 1
+( 224 256 16 ) ( 224 240 16 ) ( 224 256 192 ) bolt9 0 0 0 1 1
+}
+// brush 2
+{
+( -288 32 16 ) ( -288 48 16 ) ( -288 32 192 ) bolt9 0 0 0 1 1
+( -64 32 16 ) ( -288 32 16 ) ( -64 32 192 ) bolt9 0 0 0 1 1
+( -64 32 16 ) ( -64 48 16 ) ( -288 32 16 ) bolt9 0 0 0 1 1
+( -288 32 192 ) ( -288 48 192 ) ( -64 32 192 ) bolt9 0 0 0 1 1
+( -288 48 16 ) ( -64 48 16 ) ( -288 48 192 ) bolt9 0 0 0 1 1
+( 224 32 192 ) ( 224 48 192 ) ( 224 32 16 ) bolt9 0 0 0 1 1
+}
+// brush 3
+{
+( -288 48 192 ) ( -288 48 176 ) ( -288 240 192 ) bolt9 0 0 0 1 1
+( -64 48 192 ) ( -64 48 176 ) ( -288 48 192 ) bolt9 0 0 0 1 1
+( -64 240 176 ) ( -288 240 176 ) ( -64 48 176 ) bolt9 0 0 0 1 1
+( -64 240 192 ) ( -64 48 192 ) ( -288 240 192 ) bolt9 0 0 0 1 1
+( -288 240 192 ) ( -288 240 176 ) ( -64 240 192 ) bolt9 0 0 0 1 1
+( 224 240 192 ) ( 224 240 176 ) ( 224 48 192 ) bolt9 0 0 0 1 1
+}
+// brush 4
+{
+( -288 240 16 ) ( -288 240 32 ) ( -288 48 16 ) bolt9 0 0 0 1 1
+( -288 48 16 ) ( -288 48 32 ) ( -64 48 16 ) bolt9 0 0 0 1 1
+( -288 240 16 ) ( -288 48 16 ) ( -64 240 16 ) bolt9 0 0 0 1 1
+( -288 48 32 ) ( -288 240 32 ) ( -64 48 32 ) bolt9 0 0 0 1 1
+( -64 240 16 ) ( -64 240 32 ) ( -288 240 16 ) bolt9 0 0 0 1 1
+( 224 48 16 ) ( 224 48 32 ) ( 224 240 16 ) bolt9 0 0 0 1 1
+}
+// brush 5
+{
+( 208 48 32 ) ( 208 49 32 ) ( 208 48 33 ) bolt9 0 0 0 1 1
+( 208 48 32 ) ( 208 48 33 ) ( 209 48 32 ) bolt9 0 0 0 1 1
+( 208 48 32 ) ( 209 48 32 ) ( 208 49 32 ) bolt9 0 0 0 1 1
+( 224 240 192 ) ( 224 241 192 ) ( 225 240 192 ) bolt9 0 0 0 1 1
+( 224 240 40 ) ( 225 240 40 ) ( 224 240 41 ) bolt9 0 0 0 1 1
+( 224 240 40 ) ( 224 240 41 ) ( 224 241 40 ) bolt9 0 0 0 1 1
+}
+}
+// entity 1
+{
+"classname" "info_player_start"
+"origin" "-192 132 56"
+}
+// entity 2
+{
+"classname" "light"
+"origin" "-24 152 120"
+"_color" "0.4 0.5 0.6"
+}
+// entity 3
+{
+"classname" "func_detail"
+"_lightignore" "1"
+// brush 0
+{
+( 32 112 32 ) ( 32 113 32 ) ( 32 112 33 ) bolt9 32 0 0 1 1
+( 32 112 32 ) ( 32 112 33 ) ( 33 112 32 ) bolt9 16 0 0 1 1
+( 32 112 32 ) ( 33 112 32 ) ( 32 113 32 ) bolt9 16 -32 0 1 1
+( 112 176 48 ) ( 112 177 48 ) ( 113 176 48 ) bolt9 16 -32 0 1 1
+( 112 176 48 ) ( 113 176 48 ) ( 112 176 49 ) bolt9 16 0 0 1 1
+( 112 176 48 ) ( 112 176 49 ) ( 112 177 48 ) bolt9 32 0 0 1 1
+}
+}
+// entity 4
+{
+"classname" "func_wall"
+"_lightignore" "1"
+// brush 0
+{
+( -80 112 32 ) ( -80 113 32 ) ( -80 112 33 ) bolt9 32 0 0 1 1
+( -80 112 32 ) ( -80 112 33 ) ( -79 112 32 ) bolt9 0 0 0 1 1
+( -80 112 32 ) ( -79 112 32 ) ( -80 113 32 ) bolt9 0 -32 0 1 1
+( 0 176 48 ) ( 0 177 48 ) ( 1 176 48 ) bolt9 0 -32 0 1 1
+( 0 176 48 ) ( 1 176 48 ) ( 0 176 49 ) bolt9 0 0 0 1 1
+( 0 176 48 ) ( 0 176 49 ) ( 0 177 48 ) bolt9 32 0 0 1 1
+}
+}
diff --git a/tests/test_ltface.cc b/tests/test_ltface.cc
index c0124153..814fe275 100644
--- a/tests/test_ltface.cc
+++ b/tests/test_ltface.cc
@@ -240,7 +240,7 @@ static void CheckFaceLuxelsNonBlack(const mbsp_t &bsp, const mface_t &face)
 }
 
 static void CheckFaceLuxelAtPoint(const mbsp_t *bsp, const dmodelh2_t *model, const qvec3b &expected_color,
-    const qvec3d &point, const qvec3d &normal = {0, 0, 0})
+    const qvec3d &point, const qvec3d &normal = {0, 0, 0}, const std::vector<uint8_t> *lit = nullptr)
 {
     auto *face = BSP_FindFaceAtPoint(bsp, model, point, normal);
     REQUIRE(face);
@@ -251,7 +251,7 @@ static void CheckFaceLuxelAtPoint(const mbsp_t *bsp, const dmodelh2_t *model, co
 
     const auto coord = extents.worldToLMCoord(point);
 
-    const qvec3b sample = LM_Sample(bsp, nullptr, extents, face->lightofs, qvec2i(coord));
+    const qvec3b sample = LM_Sample(bsp, lit, extents, face->lightofs, qvec2i(coord));
     INFO("sample ", coord[0], ", ", coord[1]);
 
     CHECK(sample == expected_color);
@@ -624,3 +624,21 @@ TEST_CASE("q2_surface_lights_culling")
 
     CheckFaceLuxelAtPoint(&bsp, &bsp.dmodels[0], {155, 78, 39}, {-480, 168, 64});
 }
+
+TEST_CASE("q1_lightignore")
+{
+    auto [bsp, bspx, lit] = QbspVisLight_Q1("q1_lightignore.map", {"-bounce"});
+
+    {
+        INFO("func_wall");
+        CheckFaceLuxelAtPoint(&bsp, &bsp.dmodels[1], {0, 0, 0}, {-48, 144, 48}, {0, 0, 1}, &lit);
+    }
+    {
+        INFO("func_detail");
+        CheckFaceLuxelAtPoint(&bsp, &bsp.dmodels[0], {0, 0, 0}, {72, 144, 48}, {0, 0, 1}, &lit);
+    }
+    {
+        INFO("worldspawn (receives light)");
+        CheckFaceLuxelAtPoint(&bsp, &bsp.dmodels[0], {55, 69, 83}, {-128, 144, 32}, {0, 0, 1}, &lit);
+    }
+}