From 60e0d4a177803891720af4c5978bbf2604bed276 Mon Sep 17 00:00:00 2001
From: FengChen <vonchenplus@gmail.com>
Date: Fri, 11 Nov 2022 00:25:03 +0800
Subject: [PATCH] shader: Implement miss attribute layer

---
 src/shader_recompiler/backend/glasm/emit_glasm.cpp            | 1 +
 .../backend/glasm/emit_glasm_context_get_set.cpp              | 3 +++
 .../backend/glsl/emit_glsl_context_get_set.cpp                | 3 +++
 .../backend/spirv/emit_spirv_context_get_set.cpp              | 2 ++
 src/shader_recompiler/backend/spirv/spirv_emit_context.cpp    | 4 ++++
 5 files changed, 13 insertions(+)

diff --git a/src/shader_recompiler/backend/glasm/emit_glasm.cpp b/src/shader_recompiler/backend/glasm/emit_glasm.cpp
index 3b0176bf6..0cb1e193e 100644
--- a/src/shader_recompiler/backend/glasm/emit_glasm.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_glasm.cpp
@@ -320,6 +320,7 @@ void SetupOptions(const IR::Program& program, const Profile& profile,
     }
     if (stage == Stage::Fragment) {
         header += "OPTION ARB_draw_buffers;";
+        header += "OPTION ARB_fragment_layer_viewport;";
     }
 }
 
diff --git a/src/shader_recompiler/backend/glasm/emit_glasm_context_get_set.cpp b/src/shader_recompiler/backend/glasm/emit_glasm_context_get_set.cpp
index 0a7d42dda..9dbf9888d 100644
--- a/src/shader_recompiler/backend/glasm/emit_glasm_context_get_set.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_glasm_context_get_set.cpp
@@ -104,6 +104,9 @@ void EmitGetAttribute(EmitContext& ctx, IR::Inst& inst, IR::Attribute attr, Scal
     case IR::Attribute::PrimitiveId:
         ctx.Add("MOV.F {}.x,primitive.id;", inst);
         break;
+    case IR::Attribute::Layer:
+        ctx.Add("MOV.F {}.x,fragment.layer;", inst);
+        break;
     case IR::Attribute::PositionX:
     case IR::Attribute::PositionY:
     case IR::Attribute::PositionZ:
diff --git a/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp b/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
index d7c845469..02b84cbe6 100644
--- a/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
@@ -205,6 +205,9 @@ void EmitGetAttribute(EmitContext& ctx, IR::Inst& inst, IR::Attribute attr,
     case IR::Attribute::PrimitiveId:
         ctx.AddF32("{}=itof(gl_PrimitiveID);", inst);
         break;
+    case IR::Attribute::Layer:
+        ctx.AddF32("{}=itof(gl_Layer);", inst);
+        break;
     case IR::Attribute::PositionX:
     case IR::Attribute::PositionY:
     case IR::Attribute::PositionZ:
diff --git a/src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp b/src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp
index a4751b42d..ce33fabf5 100644
--- a/src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp
+++ b/src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp
@@ -315,6 +315,8 @@ Id EmitGetAttribute(EmitContext& ctx, IR::Attribute attr, Id vertex) {
     switch (attr) {
     case IR::Attribute::PrimitiveId:
         return ctx.OpBitcast(ctx.F32[1], ctx.OpLoad(ctx.U32[1], ctx.primitive_id));
+    case IR::Attribute::Layer:
+        return ctx.OpBitcast(ctx.F32[1], ctx.OpLoad(ctx.U32[1], ctx.layer));
     case IR::Attribute::PositionX:
     case IR::Attribute::PositionY:
     case IR::Attribute::PositionZ:
diff --git a/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp b/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
index c26ad8f93..e80662d23 100644
--- a/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
+++ b/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
@@ -1355,6 +1355,10 @@ void EmitContext::DefineInputs(const IR::Program& program) {
     if (loads[IR::Attribute::PrimitiveId]) {
         primitive_id = DefineInput(*this, U32[1], false, spv::BuiltIn::PrimitiveId);
     }
+    if (loads[IR::Attribute::Layer]) {
+        AddCapability(spv::Capability::Geometry);
+        layer = DefineInput(*this, U32[1], false, spv::BuiltIn::Layer);
+    }
     if (loads.AnyComponent(IR::Attribute::PositionX)) {
         const bool is_fragment{stage != Stage::Fragment};
         const spv::BuiltIn built_in{is_fragment ? spv::BuiltIn::Position : spv::BuiltIn::FragCoord};