From 19e9ac1db3a16f027beca4749c8187c5e47f135f Mon Sep 17 00:00:00 2001
From: RaveYard <29225776+MrRaveYard@users.noreply.github.com>
Date: Sat, 9 Sep 2023 14:38:09 +0200
Subject: [PATCH] Add cvar lm_scale for multiplying resolution of the lightmap

---
 src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp | 2 +-
 src/rendering/hwrenderer/doom_levelmesh.cpp              | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp b/src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp
index 4e059fc82..681df71cf 100644
--- a/src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp
+++ b/src/common/rendering/vulkan/accelstructs/vk_lightmap.cpp
@@ -21,7 +21,7 @@ ADD_STAT(lightmapper)
 
 CVAR(Int, lm_background_updates, 8, CVAR_NOSAVE);
 CVAR(Int, lm_max_updates, 128, CVAR_NOSAVE);
-
+CVAR(Float, lm_scale, 1.0, CVAR_NOSAVE);
 
 VkLightmap::VkLightmap(VulkanRenderDevice* fb) : fb(fb)
 {
diff --git a/src/rendering/hwrenderer/doom_levelmesh.cpp b/src/rendering/hwrenderer/doom_levelmesh.cpp
index 598c5e376..cd9dd011c 100644
--- a/src/rendering/hwrenderer/doom_levelmesh.cpp
+++ b/src/rendering/hwrenderer/doom_levelmesh.cpp
@@ -35,6 +35,8 @@ CCMD(invalidatelightmap)
 	Printf("Marked %d out of %d surfaces for update.\n", count, level.levelMesh->Surfaces.Size());
 }
 
+EXTERN_CVAR(Float, lm_scale);
+
 DoomLevelMesh::DoomLevelMesh(FLevelLocals &doomMap)
 {
 	SunColor = doomMap.SunColor; // TODO keep only one copy?
@@ -1100,6 +1102,8 @@ void DoomLevelMesh::BuildSurfaceParams(int lightMapTextureWidth, int lightMapTex
 		surface.sampleDimension = LightmapSampleDistance;
 	}
 
+	surface.sampleDimension = uint16_t(max(int(roundf(float(surface.sampleDimension) / max(1.0f / 4, float(lm_scale)))), 1));
+
 	{
 		// Round to nearest power of two
 		uint32_t n = uint16_t(surface.sampleDimension);