From ca5b07acffdd18618b2cc8b907e57d28e413df1e Mon Sep 17 00:00:00 2001
From: Stenzek <stenzek@gmail.com>
Date: Sat, 4 Nov 2023 20:28:45 +1000
Subject: [PATCH] PostProcessing: Fix for Metal renderer

---
 src/util/postprocessing.cpp             |  2 --
 src/util/postprocessing_shader_fx.cpp   | 29 ++++++++++++++-----------
 src/util/postprocessing_shader_glsl.cpp |  3 ++-
 src/util/shadergen.cpp                  |  2 +-
 4 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/src/util/postprocessing.cpp b/src/util/postprocessing.cpp
index 0ee81d7be..12b350f1c 100644
--- a/src/util/postprocessing.cpp
+++ b/src/util/postprocessing.cpp
@@ -699,8 +699,6 @@ bool PostProcessing::Apply(GPUFramebuffer* final_target, s32 final_left, s32 fin
   if (!CheckTargets(target_format, target_width, target_height))
     return false;
 
-  g_gpu_device->SetViewportAndScissor(final_left, final_top, final_width, final_height);
-
   GPUTexture* input = s_input_texture.get();
   GPUFramebuffer* input_fb = s_input_framebuffer.get();
   GPUTexture* output = s_output_texture.get();
diff --git a/src/util/postprocessing_shader_fx.cpp b/src/util/postprocessing_shader_fx.cpp
index c1f4bd110..d5a77061e 100644
--- a/src/util/postprocessing_shader_fx.cpp
+++ b/src/util/postprocessing_shader_fx.cpp
@@ -1281,10 +1281,23 @@ bool PostProcessing::ReShadeFXShader::Apply(GPUTexture* input, GPUFramebuffer* f
   for (const Pass& pass : m_passes)
   {
     GL_SCOPE_FMT("Draw pass {}", pass.name.c_str());
-
     GL_INS_FMT("Render Target: ID {} [{}]", pass.render_target, GetTextureNameForID(pass.render_target));
     GPUFramebuffer* output_fb = GetFramebufferByID(pass.render_target, input, final_target);
-    g_gpu_device->SetFramebuffer(output_fb);
+
+    if (!output_fb)
+    {
+      // Drawing to final buffer.
+      if (!g_gpu_device->BeginPresent(false))
+      {
+        GL_POP();
+        return false;
+      }
+    }
+    else
+    {
+      g_gpu_device->SetFramebuffer(output_fb);
+    }
+
     g_gpu_device->SetPipeline(pass.pipeline.get());
 
     // Set all inputs first, before the render pass starts.
@@ -1292,7 +1305,7 @@ bool PostProcessing::ReShadeFXShader::Apply(GPUTexture* input, GPUFramebuffer* f
     for (const Sampler& sampler : pass.samplers)
     {
       GL_INS_FMT("Texture Sampler {}: ID {} [{}]", sampler.slot, sampler.texture_id,
-             GetTextureNameForID(sampler.texture_id));
+                 GetTextureNameForID(sampler.texture_id));
       g_gpu_device->SetTextureSampler(sampler.slot, GetTextureByID(sampler.texture_id, input, final_target),
                                       sampler.sampler);
       bound_textures[sampler.slot] = true;
@@ -1306,16 +1319,6 @@ bool PostProcessing::ReShadeFXShader::Apply(GPUTexture* input, GPUFramebuffer* f
         g_gpu_device->SetTextureSampler(i, nullptr, nullptr);
     }
 
-    if (!output_fb)
-    {
-      // Drawing to final buffer.
-      if (!g_gpu_device->BeginPresent(false))
-      {
-        GL_POP();
-        return false;
-      }
-    }
-
     g_gpu_device->Draw(pass.num_vertices, 0);
   }
 
diff --git a/src/util/postprocessing_shader_glsl.cpp b/src/util/postprocessing_shader_glsl.cpp
index 0f6427f4f..6845fe501 100644
--- a/src/util/postprocessing_shader_glsl.cpp
+++ b/src/util/postprocessing_shader_glsl.cpp
@@ -176,6 +176,7 @@ bool PostProcessing::GLSLShader::Apply(GPUTexture* input, GPUFramebuffer* final_
 
   g_gpu_device->SetPipeline(m_pipeline.get());
   g_gpu_device->SetTextureSampler(0, input, m_sampler.get());
+  g_gpu_device->SetViewportAndScissor(final_left, final_top, final_width, final_height);
 
   const u32 uniforms_size = GetUniformsSize();
   void* uniforms = g_gpu_device->MapUniformBuffer(uniforms_size);
@@ -377,7 +378,7 @@ static float4 o_col0;
   {
     if (m_use_glsl_interface_blocks)
     {
-      if (IsVulkan())
+      if (IsVulkan() || IsMetal())
         ss << "layout(location = 0) ";
 
       ss << "in VertexData {\n";
diff --git a/src/util/shadergen.cpp b/src/util/shadergen.cpp
index 2c5508e10..f8d0c95f1 100644
--- a/src/util/shadergen.cpp
+++ b/src/util/shadergen.cpp
@@ -19,7 +19,7 @@ ShaderGen::ShaderGen(RenderAPI render_api, bool supports_dual_source_blend)
     m_spirv(render_api == RenderAPI::Vulkan || render_api == RenderAPI::Metal),
     m_supports_dual_source_blend(supports_dual_source_blend), m_use_glsl_interface_blocks(false)
 {
-#if defined(ENABLE_OPENGL) || defined(ENABLE_VULKAN)
+#if defined(ENABLE_OPENGL) || defined(ENABLE_VULKAN) || defined(__APPLE__)
   if (m_glsl)
   {
 #ifdef ENABLE_OPENGL