From 6b4e26c479494b79ede05ddfe20e95b811deba43 Mon Sep 17 00:00:00 2001
From: clayjohn <claynjohn@gmail.com>
Date: Thu, 8 Jan 2026 16:18:01 -0800
Subject: [PATCH] Add compatibility handler to RADIANCE in sky shaders since
 the type was changed.

It was a textureCube, but now it is a texture2D. For compatibility purposes we need to continue exposing a cube texture. So we need to add this scaffolding to properly sample from it.
---
 servers/rendering/shader_compiler.cpp | 11 +++++++++++
 servers/rendering/shader_language.cpp |  7 ++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/servers/rendering/shader_compiler.cpp b/servers/rendering/shader_compiler.cpp
index e367b26df23..9324d4f71ec 100644
--- a/servers/rendering/shader_compiler.cpp
+++ b/servers/rendering/shader_compiler.cpp
@@ -1168,6 +1168,7 @@ String ShaderCompiler::_dump_node_code(const SL::Node *p_node, int p_level, Gene
 
 					bool is_texture_func = false;
 					bool is_screen_texture = false;
+					bool is_radiance_texture = false;
 					bool texture_func_no_uv = false;
 					bool texture_func_returns_data = false;
 
@@ -1314,10 +1315,16 @@ String ShaderCompiler::_dump_node_code(const SL::Node *p_node, int p_level, Gene
 									}
 								}
 
+								if (texture_uniform == SNAME("RADIANCE")) {
+									is_radiance_texture = true;
+								}
+
 								String data_type_name = "";
 								if (actions.check_multiview_samplers && (is_screen_texture || is_depth_texture || is_normal_roughness_texture)) {
 									data_type_name = "multiviewSampler";
 									multiview_uv_needed = true;
+								} else if (is_radiance_texture) {
+									data_type_name = "sampler2D";
 								} else {
 									data_type_name = ShaderLanguage::get_datatype_name(onode->arguments[i]->get_datatype());
 								}
@@ -1350,6 +1357,10 @@ String ShaderCompiler::_dump_node_code(const SL::Node *p_node, int p_level, Gene
 							// UV coordinate after using color, depth or normal roughness texture.
 							node_code = "multiview_uv(" + node_code + ".xy)";
 
+							code += node_code;
+						} else if (is_radiance_texture && !texture_func_no_uv && i == 2) {
+							node_code = "vec3_to_oct_with_border(" + node_code + ", params.border_size)";
+
 							code += node_code;
 						} else {
 							code += node_code;
diff --git a/servers/rendering/shader_language.cpp b/servers/rendering/shader_language.cpp
index b772fa417de..c577e5c7863 100644
--- a/servers/rendering/shader_language.cpp
+++ b/servers/rendering/shader_language.cpp
@@ -6473,7 +6473,7 @@ ShaderLanguage::Node *ShaderLanguage::_parse_expression(BlockNode *p_block, cons
 												ShaderNode::Uniform::Hint hint = u->hint;
 
 												if (hint == ShaderNode::Uniform::HINT_DEPTH_TEXTURE || hint == ShaderNode::Uniform::HINT_SCREEN_TEXTURE || hint == ShaderNode::Uniform::HINT_NORMAL_ROUGHNESS_TEXTURE) {
-													_set_error(vformat(RTR("Unable to pass a multiview texture sampler as a parameter to custom function. Consider to sample it in the main function and then pass the vector result to it."), get_uniform_hint_name(hint)));
+													_set_error(vformat(RTR("Unable to pass a multiview texture sampler as a parameter to a custom function. Consider sampling it in the main function and then passing the vector result to the custom function."), get_uniform_hint_name(hint)));
 													return nullptr;
 												}
 											}
@@ -6483,6 +6483,11 @@ ShaderLanguage::Node *ShaderLanguage::_parse_expression(BlockNode *p_block, cons
 												return nullptr;
 											}
 										} else if (p_function_info.built_ins.has(varname)) {
+											if (is_custom_func && varname == SNAME("RADIANCE")) {
+												_set_error(RTR("Unable to pass RADIANCE texture sampler as a parameter to a custom function. Consider sampling it in the main function and then passing the vector result to the custom function."));
+												return nullptr;
+											}
+
 											//a built-in
 											if (!_propagate_function_call_sampler_builtin_reference(name, i, varname)) {
 												return nullptr;