glsl: Implement geometry shaders

4 files changed, 62 insertions, 9 deletions

diff --git a/src/shader_recompiler/backend/glsl/emit_context.cpp b/src/shader_recompiler/backend/glsl/emit_context.cpp
index 2a5ec7414..923060386 100644
--- a/src/shader_recompiler/backend/glsl/emit_context.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_context.cpp
@@ -21,6 +21,15 @@ std::string_view InterpDecorator(Interpolation interp) {
     throw InvalidArgument("Invalid interpolation {}", interp);
 }
 
+std::string_view ArrayDecorator(Stage stage) {
+    switch (stage) {
+    case Stage::Geometry:
+        return "[1]";
+    default:
+        return "";
+    }
+}
+
 std::string_view SamplerType(TextureType type, bool is_depth) {
     if (is_depth) {
         switch (type) {
@@ -64,6 +73,33 @@ std::string_view SamplerType(TextureType type, bool is_depth) {
     }
 }
 
+std::string_view InputPrimitive(InputTopology topology) {
+    switch (topology) {
+    case InputTopology::Points:
+        return "points";
+    case InputTopology::Lines:
+        return "lines";
+    case InputTopology::LinesAdjacency:
+        return "lines_adjacency";
+    case InputTopology::Triangles:
+        return "triangles";
+    case InputTopology::TrianglesAdjacency:
+        return "triangles_adjacency";
+    }
+    throw InvalidArgument("Invalid input topology {}", topology);
+}
+
+std::string_view OutputPrimitive(OutputTopology topology) {
+    switch (topology) {
+    case OutputTopology::PointList:
+        return "points";
+    case OutputTopology::LineStrip:
+        return "line_strip";
+    case OutputTopology::TriangleStrip:
+        return "triangle_strip";
+    }
+    throw InvalidArgument("Invalid output topology {}", topology);
+}
 } // namespace
 
 EmitContext::EmitContext(IR::Program& program, Bindings& bindings, const Profile& profile_,
@@ -85,6 +121,9 @@ EmitContext::EmitContext(IR::Program& program, Bindings& bindings, const Profile
         break;
     case Stage::Geometry:
         stage_name = "gs";
+        header += fmt::format("layout({})in;layout({}, max_vertices={})out;\n",
+                              InputPrimitive(runtime_info.input_topology),
+                              OutputPrimitive(program.output_topology), program.output_vertices);
         break;
     case Stage::Fragment:
         stage_name = "fs";
@@ -99,8 +138,9 @@ EmitContext::EmitContext(IR::Program& program, Bindings& bindings, const Profile
     for (size_t index = 0; index < info.input_generics.size(); ++index) {
         const auto& generic{info.input_generics[index]};
         if (generic.used) {
-            header += fmt::format("layout(location={}) {} in vec4 in_attr{};", index,
-                                  InterpDecorator(generic.interpolation), index);
+            header +=
+                fmt::format("layout(location={}){} in vec4 in_attr{}{};", index,
+                            InterpDecorator(generic.interpolation), index, ArrayDecorator(stage));
         }
     }
     for (size_t index = 0; index < info.stores_frag_color.size(); ++index) {
@@ -126,8 +166,6 @@ EmitContext::EmitContext(IR::Program& program, Bindings& bindings, const Profile
 void EmitContext::SetupExtensions(std::string&) {
     // TODO: track this usage
     header += "#extension GL_ARB_sparse_texture2 : enable\n";
-    header += "#extension GL_ARB_shader_viewport_layer_array : enable\n";
-    header += "#extension GL_NV_viewport_array2 : enable\n";
     header += "#extension GL_EXT_texture_shadow_lod : enable\n";
     if (info.uses_int64) {
         header += "#extension GL_ARB_gpu_shader_int64 : enable\n";
@@ -157,6 +195,10 @@ void EmitContext::SetupExtensions(std::string&) {
             header += "#extension GL_ARB_gpu_shader_int64 : enable\n";
         }
     }
+    if (info.stores_viewport_index) {
+        header += "#extension GL_ARB_shader_viewport_layer_array : enable\n";
+        header += "#extension GL_NV_viewport_array2 : enable\n";
+    }
 }
 
 void EmitContext::DefineConstantBuffers(Bindings& bindings) {
diff --git a/src/shader_recompiler/backend/glsl/emit_glsl.cpp b/src/shader_recompiler/backend/glsl/emit_glsl.cpp
index 19cf4e46b..f467d978c 100644
--- a/src/shader_recompiler/backend/glsl/emit_glsl.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_glsl.cpp
@@ -162,7 +162,7 @@ void EmitCode(EmitContext& ctx, const IR::Program& program) {
             break;
         default:
             fmt::print("{}", node.type);
-            throw NotImplementedException("{}", node.type);
+            throw NotImplementedException("AbstractSyntaxNode::Type {}", node.type);
             break;
         }
     }
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 c66b4b282..28e89a0a6 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
@@ -19,6 +19,15 @@ u32 CbufIndex(u32 offset) {
 char OffsetSwizzle(u32 offset) {
     return SWIZZLE[CbufIndex(offset)];
 }
+
+bool IsInputArray(Stage stage) {
+    return stage == Stage::Geometry || stage == Stage::TessellationControl ||
+           stage == Stage::TessellationEval;
+}
+
+std::string VertexIndex(EmitContext& ctx, std::string_view vertex) {
+    return IsInputArray(ctx.stage) ? fmt::format("[{}]", vertex) : "";
+}
 } // namespace
 
 void EmitGetCbufU8([[maybe_unused]] EmitContext& ctx, [[maybe_unused]] IR::Inst& inst,
@@ -128,7 +137,7 @@ void EmitGetAttribute(EmitContext& ctx, IR::Inst& inst, IR::Attribute attr,
     const char swizzle{"xyzw"[element]};
     if (IR::IsGeneric(attr)) {
         const u32 index{IR::GenericAttributeIndex(attr)};
-        ctx.AddF32("{}=in_attr{}.{};", inst, index, swizzle);
+        ctx.AddF32("{}=in_attr{}{}.{};", inst, index, VertexIndex(ctx, vertex), swizzle);
         return;
     }
     switch (attr) {
@@ -139,9 +148,11 @@ void EmitGetAttribute(EmitContext& ctx, IR::Inst& inst, IR::Attribute attr,
         switch (ctx.stage) {
         case Stage::VertexA:
         case Stage::VertexB:
-        case Stage::Geometry:
             ctx.AddF32("{}=gl_Position.{};", inst, swizzle);
             break;
+        case Stage::Geometry:
+            ctx.AddF32("{}=gl_in[{}].gl_Position.{};", inst, vertex, swizzle);
+            break;
         case Stage::Fragment:
             ctx.AddF32("{}=gl_FragCoord.{};", inst, swizzle);
             break;
diff --git a/src/shader_recompiler/backend/glsl/emit_glsl_not_implemented.cpp b/src/shader_recompiler/backend/glsl/emit_glsl_not_implemented.cpp
index e3d0b15ba..9e5715605 100644
--- a/src/shader_recompiler/backend/glsl/emit_glsl_not_implemented.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_glsl_not_implemented.cpp
@@ -103,11 +103,11 @@ void EmitEpilogue(EmitContext& ctx) {
 }
 
 void EmitEmitVertex(EmitContext& ctx, const IR::Value& stream) {
-    NotImplemented();
+    ctx.Add("EmitStreamVertex(int({}));", ctx.var_alloc.Consume(stream));
 }
 
 void EmitEndPrimitive(EmitContext& ctx, const IR::Value& stream) {
-    NotImplemented();
+    ctx.Add("EndStreamPrimitive(int({}));", ctx.var_alloc.Consume(stream));
 }
 
 void EmitGetRegister(EmitContext& ctx) {