From 7619b7d427437cb58df0f9fc57a7d6b3f5c45f9c Mon Sep 17 00:00:00 2001
From: ameerj <52414509+ameerj@users.noreply.github.com>
Date: Sat, 29 May 2021 01:53:32 -0400
Subject: [PATCH] glsl: Implement TEX depth functions

---
 .../backend/glsl/emit_context.cpp             | 24 +++++++++++++++--
 .../backend/glsl/emit_glsl_image.cpp          | 26 +++++++++++++++++--
 2 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/src/shader_recompiler/backend/glsl/emit_context.cpp b/src/shader_recompiler/backend/glsl/emit_context.cpp
index eb1d8266f..94ba9af7c 100644
--- a/src/shader_recompiler/backend/glsl/emit_context.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_context.cpp
@@ -21,7 +21,26 @@ std::string_view InterpDecorator(Interpolation interp) {
     throw InvalidArgument("Invalid interpolation {}", interp);
 }
 
-std::string_view SamplerType(TextureType type) {
+std::string_view SamplerType(TextureType type, bool is_depth) {
+    if (is_depth) {
+        switch (type) {
+        case TextureType::Color1D:
+            return "sampler1DShadow";
+        case TextureType::ColorArray1D:
+            return "sampler1DArrayShadow";
+        case TextureType::Color2D:
+            return "sampler2DShadow";
+        case TextureType::ColorArray2D:
+            return "sampler2DArrayShadow";
+        case TextureType::ColorCube:
+            return "samplerCubeShadow";
+        case TextureType::ColorArrayCube:
+            return "samplerCubeArrayShadow";
+        default:
+            fmt::print("Texture type: {}", type);
+            throw NotImplementedException("Texture type: {}", type);
+        }
+    }
     switch (type) {
     case TextureType::Color1D:
         return "sampler1D";
@@ -110,6 +129,7 @@ EmitContext::EmitContext(IR::Program& program, Bindings& bindings, const Profile
 void EmitContext::SetupExtensions(std::string&) {
     header += "#extension GL_ARB_separate_shader_objects : enable\n";
     header += "#extension GL_ARB_sparse_texture2 : enable\n";
+    header += "#extension GL_EXT_texture_shadow_lod : enable\n";
     // header += "#extension GL_ARB_texture_cube_map_array : enable\n";
     if (info.uses_int64) {
         header += "#extension GL_ARB_gpu_shader_int64 : enable\n";
@@ -227,7 +247,7 @@ void EmitContext::SetupImages(Bindings& bindings) {
     }
     texture_bindings.reserve(info.texture_descriptors.size());
     for (const auto& desc : info.texture_descriptors) {
-        const auto sampler_type{SamplerType(desc.type)};
+        const auto sampler_type{SamplerType(desc.type, desc.is_depth)};
         texture_bindings.push_back(bindings.texture);
         const auto indices{bindings.texture + desc.count};
         for (u32 index = bindings.texture; index < indices; ++index) {
diff --git a/src/shader_recompiler/backend/glsl/emit_glsl_image.cpp b/src/shader_recompiler/backend/glsl/emit_glsl_image.cpp
index 71eb3ac2b..4381ed351 100644
--- a/src/shader_recompiler/backend/glsl/emit_glsl_image.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_glsl_image.cpp
@@ -120,7 +120,17 @@ void EmitImageSampleDrefImplicitLod([[maybe_unused]] EmitContext& ctx,
                                     [[maybe_unused]] std::string_view dref,
                                     [[maybe_unused]] std::string_view bias_lc,
                                     [[maybe_unused]] const IR::Value& offset) {
-    throw NotImplementedException("GLSL Instruction");
+    const auto info{inst.Flags<IR::TextureInstInfo>()};
+    if (info.has_bias) {
+        throw NotImplementedException("Bias texture samples");
+    }
+    if (info.has_lod_clamp) {
+        throw NotImplementedException("Lod clamp samples");
+    }
+    const auto bias{info.has_bias ? fmt::format(",{}", bias_lc) : ""};
+    const auto texture{Texture(ctx, info, index)};
+    const auto vec_cast{info.type == TextureType::ColorArrayCube ? "vec4" : "vec3"};
+    ctx.AddF32("{}=texture({},{}({},{}){});", inst, texture, vec_cast, dref, coords, bias);
 }
 
 void EmitImageSampleDrefExplicitLod([[maybe_unused]] EmitContext& ctx,
@@ -130,7 +140,19 @@ void EmitImageSampleDrefExplicitLod([[maybe_unused]] EmitContext& ctx,
                                     [[maybe_unused]] std::string_view dref,
                                     [[maybe_unused]] std::string_view lod_lc,
                                     [[maybe_unused]] const IR::Value& offset) {
-    throw NotImplementedException("GLSL Instruction");
+    const auto info{inst.Flags<IR::TextureInstInfo>()};
+    if (info.has_bias) {
+        throw NotImplementedException("Bias texture samples");
+    }
+    if (info.has_lod_clamp) {
+        throw NotImplementedException("Lod clamp samples");
+    }
+    const auto texture{Texture(ctx, info, index)};
+    if (info.type == TextureType::ColorArrayCube) {
+        ctx.AddF32("{}=textureLod({},{},{},{});", inst, texture, coords, dref, lod_lc);
+    } else {
+        ctx.AddF32("{}=textureLod({},vec3({},{}),{});", inst, texture, coords, dref, lod_lc);
+    }
 }
 
 void EmitImageGather([[maybe_unused]] EmitContext& ctx, [[maybe_unused]] IR::Inst& inst,