From db2f0f410810d3d8310a6a476a8bcfd5e509869e Mon Sep 17 00:00:00 2001
From: ReinUsesLisp <reinuseslisp@airmail.cc>
Date: Sun, 16 May 2021 17:52:30 -0300
Subject: [PATCH] emit_glasm: Enable ARB_draw_buffers when needed

---
 src/shader_recompiler/backend/glasm/emit_context.cpp | 2 +-
 src/shader_recompiler/backend/glasm/emit_glasm.cpp   | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/shader_recompiler/backend/glasm/emit_context.cpp b/src/shader_recompiler/backend/glasm/emit_context.cpp
index 66c954ff6..4903e9d8e 100644
--- a/src/shader_recompiler/backend/glasm/emit_context.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_context.cpp
@@ -71,7 +71,7 @@ EmitContext::EmitContext(IR::Program& program) {
         if (index == 0) {
             Add("OUTPUT frag_color0=result.color;");
         } else {
-            Add("OUTPUT frag_color{}[]=result.color[{}];", index, index);
+            Add("OUTPUT frag_color{}=result.color[{}];", index, index);
         }
     }
     for (size_t index = 0; index < program.info.stores_generics.size(); ++index) {
diff --git a/src/shader_recompiler/backend/glasm/emit_glasm.cpp b/src/shader_recompiler/backend/glasm/emit_glasm.cpp
index 0a76423f4..0c591f73c 100644
--- a/src/shader_recompiler/backend/glasm/emit_glasm.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_glasm.cpp
@@ -283,6 +283,10 @@ void SetupOptions(std::string& header, Info info) {
     if (info.uses_subgroup_shuffles) {
         header += "OPTION NV_shader_thread_shuffle;";
     }
+    const auto non_zero_frag_colors{info.stores_frag_color | std::views::drop(1)};
+    if (std::ranges::find(non_zero_frag_colors, true) != non_zero_frag_colors.end()) {
+        header += "OPTION ARB_draw_buffers;";
+    }
 }
 
 std::string_view StageHeader(Stage stage) {