From ba06234309ee1b4510ad5251b9957853c572e24c Mon Sep 17 00:00:00 2001
From: retrotails <10767978+retrotails@users.noreply.github.com>
Date: Wed, 21 May 2025 06:29:07 -0400
Subject: [PATCH] Fix light range in voxel GI

---
 servers/rendering/renderer_rd/environment/gi.cpp       |  7 ++++++-
 servers/rendering/renderer_rd/environment/gi.h         |  5 +++--
 .../renderer_rd/shaders/environment/voxel_gi.glsl      | 10 +++++++---
 3 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/servers/rendering/renderer_rd/environment/gi.cpp b/servers/rendering/renderer_rd/environment/gi.cpp
index b6a637758a..dacb122e46 100644
--- a/servers/rendering/renderer_rd/environment/gi.cpp
+++ b/servers/rendering/renderer_rd/environment/gi.cpp
@@ -2943,6 +2943,10 @@ void GI::VoxelGIInstance::update(bool p_update_light_instances, const Vector<RID
 		}
 	}
 
+	// probe size relative to 1 unit in world space
+	Vector3 ps = gi->voxel_gi_get_octree_size(probe) / gi->voxel_gi_get_bounds(probe).size;
+	float cell_size = (1.0 / MAX(MAX(ps.x, ps.y), ps.z));
+
 	if (has_dynamic_object_data || p_update_light_instances || p_dynamic_objects.size()) {
 		// PROCESS MIPMAPS
 		if (mipmaps.size()) {
@@ -2961,6 +2965,7 @@ void GI::VoxelGIInstance::update(bool p_update_light_instances, const Vector<RID
 			push_constant.dynamic_range = gi->voxel_gi_get_dynamic_range(probe);
 			push_constant.light_count = light_count;
 			push_constant.aniso_strength = 0;
+			push_constant.cell_size = cell_size;
 
 			/*		print_line("probe update to version " + itos(last_probe_version));
 			print_line("propagation " + rtos(push_constant.propagation));
@@ -3161,9 +3166,9 @@ void GI::VoxelGIInstance::update(bool p_update_light_instances, const Vector<RID
 				push_constant.prev_rect_size[1] = 0;
 				push_constant.on_mipmap = false;
 				push_constant.propagation = gi->voxel_gi_get_propagation(probe);
+				push_constant.cell_size = cell_size;
 				push_constant.pad[0] = 0;
 				push_constant.pad[1] = 0;
-				push_constant.pad[2] = 0;
 
 				//process lighting
 				RD::ComputeListID compute_list = RD::get_singleton()->compute_list_begin();
diff --git a/servers/rendering/renderer_rd/environment/gi.h b/servers/rendering/renderer_rd/environment/gi.h
index 0e21e85d75..adb1c6f1a0 100644
--- a/servers/rendering/renderer_rd/environment/gi.h
+++ b/servers/rendering/renderer_rd/environment/gi.h
@@ -188,7 +188,7 @@ private:
 		uint32_t cell_offset;
 		uint32_t cell_count;
 		float aniso_strength;
-		uint32_t pad;
+		float cell_size;
 	};
 
 	struct VoxelGIDynamicPushConstant {
@@ -209,7 +209,8 @@ private:
 		float dynamic_range;
 		uint32_t on_mipmap;
 		float propagation;
-		float pad[3];
+		float cell_size;
+		float pad[2];
 	};
 
 	VoxelGILight *voxel_gi_lights = nullptr;
diff --git a/servers/rendering/renderer_rd/shaders/environment/voxel_gi.glsl b/servers/rendering/renderer_rd/shaders/environment/voxel_gi.glsl
index 6e9e0f82b3..12137e94f7 100644
--- a/servers/rendering/renderer_rd/shaders/environment/voxel_gi.glsl
+++ b/servers/rendering/renderer_rd/shaders/environment/voxel_gi.glsl
@@ -86,7 +86,7 @@ layout(push_constant, std430) uniform Params {
 	uint cell_offset;
 	uint cell_count;
 	float aniso_strength;
-	uint pad;
+	float cell_size;
 }
 params;
 
@@ -126,7 +126,8 @@ layout(push_constant, std430) uniform Params {
 	float dynamic_range;
 	bool on_mipmap;
 	float propagation;
-	float pad[3];
+	float cell_size;
+	float pad[2];
 }
 params;
 
@@ -209,7 +210,10 @@ bool compute_light_vector(uint light, vec3 pos, out float attenuation, out vec3
 			return false;
 		}
 
-		attenuation = get_omni_attenuation(distance, 1.0 / lights.data[light].radius, lights.data[light].attenuation);
+		attenuation = get_omni_attenuation(
+				distance * params.cell_size,
+				1.0 / (lights.data[light].radius * params.cell_size),
+				lights.data[light].attenuation);
 
 		if (lights.data[light].type == LIGHT_TYPE_SPOT) {
 			vec3 rel = normalize(pos - light_pos);