PostProcessing: Add native width/height inputs

Available in GLSL as GetNativeSize(), GetUpscaleMultiplier(), and in
reshade as native_width/native_height/upscale_multiplier.

GetPaddedOriginalSize() is now deprecated, as it does not make since
since the postfx shader runs with a window-sized off-screen target as an
input, not the internal render texture.

src/core/gpu.cpp

@@ -2066,9 +2066,17 @@ bool GPU::RenderDisplay(GPUTexture* target, const Common::Rectangle<s32>& draw_r
 
   if (really_postfx)
   {
+    // "original size" in postfx includes padding.
+    const float upscale_x =
+      static_cast<float>(m_display_texture_view_width) / static_cast<float>(m_display_active_width);
+    const float upscale_y =
+      static_cast<float>(m_display_texture_view_height) / static_cast<float>(m_display_active_height);
+    const s32 orig_width = static_cast<s32>(std::ceil(m_display_width * upscale_x));
+    const s32 orig_height = static_cast<s32>(std::ceil(m_display_height * upscale_y));
+
     return PostProcessing::Apply(target, real_draw_rect.left, real_draw_rect.top, real_draw_rect.GetWidth(),
-                                 real_draw_rect.GetHeight(), m_display_texture_view_width,
-                                 m_display_texture_view_height);
+                                 real_draw_rect.GetHeight(), orig_width, orig_height, m_display_width,
+                                 m_display_height);
   }
   else
   {

src/util/postprocessing.cpp

@@ -728,7 +728,7 @@ void PostProcessing::DestroyTextures()
 }
 
 bool PostProcessing::Apply(GPUTexture* final_target, s32 final_left, s32 final_top, s32 final_width, s32 final_height,
-                           s32 orig_width, s32 orig_height)
+                           s32 orig_width, s32 orig_height, s32 native_width, s32 native_height)
 {
   GL_SCOPE("PostProcessing Apply");
 
@@ -741,7 +741,7 @@ bool PostProcessing::Apply(GPUTexture* final_target, s32 final_left, s32 final_t
     const bool is_final = (stage.get() == s_stages.back().get());
 
     if (!stage->Apply(input, is_final ? final_target : output, final_left, final_top, final_width, final_height,
-                      orig_width, orig_height, s_target_width, s_target_height))
+                      orig_width, orig_height, native_width, native_height, s_target_width, s_target_height))
     {
       return false;
     }

src/util/postprocessing.h

@@ -125,10 +125,11 @@ void Shutdown();
 GPUTexture* GetInputTexture();
 const Common::Timer& GetTimer();
 
-bool CheckTargets(GPUTexture::Format target_format, u32 target_width, u32 target_height, ProgressCallback* progress = nullptr);
+bool CheckTargets(GPUTexture::Format target_format, u32 target_width, u32 target_height,
+                  ProgressCallback* progress = nullptr);
 
 bool Apply(GPUTexture* final_target, s32 final_left, s32 final_top, s32 final_width, s32 final_height, s32 orig_width,
-           s32 orig_height);
+           s32 orig_height, s32 native_width, s32 native_height);
 
 GPUSampler* GetSampler(const GPUSampler::Config& config);
 GPUTexture* GetDummyTexture();

src/util/postprocessing_shader.h

@@ -49,7 +49,8 @@ public:
   virtual bool CompilePipeline(GPUTexture::Format format, u32 width, u32 height, ProgressCallback* progress) = 0;
 
   virtual bool Apply(GPUTexture* input, GPUTexture* final_target, s32 final_left, s32 final_top, s32 final_width,
-                     s32 final_height, s32 orig_width, s32 orig_height, u32 target_width, u32 target_height) = 0;
+                     s32 final_height, s32 orig_width, s32 orig_height, s32 native_width, s32 native_height,
+                     u32 target_width, u32 target_height) = 0;
 
 protected:
   static void ParseKeyValue(std::string_view line, std::string_view* key, std::string_view* value);

src/util/postprocessing_shader_fx.cpp

@@ -1,4 +1,5 @@
 // SPDX-FileCopyrightText: 2019-2024 Connor McLaughlin <stenzek@gmail.com>
+// SPDX-FileCopyrightText: 2019-2024 Connor McLaughlin <stenzek@gmail.com>
 // SPDX-License-Identifier: (GPL-3.0 OR CC-BY-NC-ND-4.0)
 
 #include "postprocessing_shader_fx.h"
@@ -863,6 +864,29 @@ bool PostProcessing::ReShadeFXShader::GetSourceOption(const reshadefx::uniform_i
                                                          SourceOptionType::InternalHeight;
       return true;
     }
+    else if (source == "nativewidth")
+    {
+      *si = (ui.type.base == reshadefx::type::t_float) ? SourceOptionType::NativeWidthF : SourceOptionType::NativeWidth;
+      return true;
+    }
+    else if (source == "nativeheight")
+    {
+      *si =
+        (ui.type.base == reshadefx::type::t_float) ? SourceOptionType::NativeHeightF : SourceOptionType::NativeHeight;
+      return true;
+    }
+    else if (source == "upscale_multiplier")
+    {
+      if (!ui.type.is_floating_point() || ui.type.components() != 1)
+      {
+        Error::SetString(error, fmt::format("Unexpected type '{}' for upscale_multiplier source in uniform '{}'",
+                                            ui.type.description(), ui.name));
+        return false;
+      }
+
+      *si = SourceOptionType::UpscaleMultiplier;
+      return true;
+    }
     else
     {
       Error::SetString(error, fmt::format("Unknown source '{}' in uniform '{}'", source, ui.name));
@@ -1318,7 +1342,7 @@ bool PostProcessing::ReShadeFXShader::ResizeOutput(GPUTexture::Format format, u3
 
 bool PostProcessing::ReShadeFXShader::Apply(GPUTexture* input, GPUTexture* final_target, s32 final_left, s32 final_top,
                                             s32 final_width, s32 final_height, s32 orig_width, s32 orig_height,
-                                            u32 target_width, u32 target_height)
+                                            s32 native_width, s32 native_height, u32 target_width, u32 target_height)
 {
   GL_PUSH_FMT("PostProcessingShaderFX {}", m_name);
 
@@ -1452,8 +1476,8 @@ bool PostProcessing::ReShadeFXShader::Apply(GPUTexture* input, GPUTexture* final
         case SourceOptionType::InternalWidth:
         case SourceOptionType::InternalHeight:
         {
-          const s32 value =
-            (so.source == SourceOptionType::BufferWidth) ? static_cast<s32>(orig_width) : static_cast<s32>(orig_height);
+          const s32 value = (so.source == SourceOptionType::InternalWidth) ? static_cast<s32>(orig_width) :
+                                                                             static_cast<s32>(orig_height);
           std::memcpy(dst, &value, sizeof(value));
         }
         break;
@@ -1461,8 +1485,33 @@ bool PostProcessing::ReShadeFXShader::Apply(GPUTexture* input, GPUTexture* final
         case SourceOptionType::InternalWidthF:
         case SourceOptionType::InternalHeightF:
         {
-          const float value = (so.source == SourceOptionType::BufferWidthF) ? static_cast<float>(orig_width) :
-                                                                              static_cast<float>(orig_height);
+          const float value = (so.source == SourceOptionType::InternalWidthF) ? static_cast<float>(orig_width) :
+                                                                                static_cast<float>(orig_height);
+          std::memcpy(dst, &value, sizeof(value));
+        }
+        break;
+
+        case SourceOptionType::NativeWidth:
+        case SourceOptionType::NativeHeight:
+        {
+          const s32 value = (so.source == SourceOptionType::NativeWidth) ? static_cast<s32>(native_width) :
+                                                                           static_cast<s32>(native_height);
+          std::memcpy(dst, &value, sizeof(value));
+        }
+        break;
+
+        case SourceOptionType::NativeWidthF:
+        case SourceOptionType::NativeHeightF:
+        {
+          const float value = (so.source == SourceOptionType::NativeWidthF) ? static_cast<float>(native_width) :
+                                                                              static_cast<float>(native_height);
+          std::memcpy(dst, &value, sizeof(value));
+        }
+        break;
+
+        case SourceOptionType::UpscaleMultiplier:
+        {
+          const float value = static_cast<float>(orig_width) / static_cast<float>(native_width);
           std::memcpy(dst, &value, sizeof(value));
         }
         break;

src/util/postprocessing_shader_fx.h

@@ -31,7 +31,8 @@ public:
   bool ResizeOutput(GPUTexture::Format format, u32 width, u32 height) override;
   bool CompilePipeline(GPUTexture::Format format, u32 width, u32 height, ProgressCallback* progress) override;
   bool Apply(GPUTexture* input, GPUTexture* final_target, s32 final_left, s32 final_top, s32 final_width,
-             s32 final_height, s32 orig_width, s32 orig_height, u32 target_width, u32 target_height) override;
+             s32 final_height, s32 orig_width, s32 orig_height, s32 native_width, s32 native_height, u32 target_width,
+             u32 target_height) override;
 
 private:
   using TextureID = s32;
@@ -60,6 +61,11 @@ private:
     InternalHeight,
     InternalWidthF,
     InternalHeightF,
+    NativeWidth,
+    NativeHeight,
+    NativeWidthF,
+    NativeHeightF,
+    UpscaleMultiplier,
 
     MaxCount
   };

src/util/postprocessing_shader_glsl.cpp

@@ -71,7 +71,8 @@ u32 PostProcessing::GLSLShader::GetUniformsSize() const
 void PostProcessing::GLSLShader::FillUniformBuffer(void* buffer, u32 texture_width, s32 texture_height,
                                                    s32 texture_view_x, s32 texture_view_y, s32 texture_view_width,
                                                    s32 texture_view_height, u32 window_width, u32 window_height,
-                                                   s32 original_width, s32 original_height, float time) const
+                                                   s32 original_width, s32 original_height, s32 native_width,
+                                                   s32 native_height, float time) const
 {
   CommonUniforms* common = static_cast<CommonUniforms*>(buffer);
 
@@ -91,17 +92,11 @@ void PostProcessing::GLSLShader::FillUniformBuffer(void* buffer, u32 texture_wid
   common->window_resolution[1] = static_cast<float>(window_height);
   common->rcp_window_resolution[0] = 1.0f / static_cast<float>(window_width);
   common->rcp_window_resolution[1] = 1.0f / static_cast<float>(window_height);
-
-  // pad the "original size" relative to the positioning on the screen
-  const float view_scale_x = static_cast<float>(original_width) / static_cast<float>(texture_view_width);
-  const float view_scale_y = static_cast<float>(original_height) / static_cast<float>(texture_view_height);
-  const s32 view_pad_x = texture_view_x + (texture_width - texture_view_width - texture_view_x);
-  const s32 view_pad_y = texture_view_y + (texture_height - texture_view_height - texture_view_y);
   common->original_size[0] = static_cast<float>(original_width);
   common->original_size[1] = static_cast<float>(original_height);
-  common->padded_original_size[0] = common->original_size[0] + static_cast<float>(view_pad_x) * view_scale_x;
-  common->padded_original_size[1] = common->original_size[1] + static_cast<float>(view_pad_y) * view_scale_y;
-
+  common->native_size[0] = static_cast<float>(native_width);
+  common->native_size[1] = static_cast<float>(native_height);
+  common->upscale_multiplier = static_cast<float>(original_width) / static_cast<float>(native_width);
   common->time = time;
 
   u8* option_values = reinterpret_cast<u8*>(common + 1);
@@ -160,7 +155,7 @@ bool PostProcessing::GLSLShader::CompilePipeline(GPUTexture::Format format, u32
 
 bool PostProcessing::GLSLShader::Apply(GPUTexture* input, GPUTexture* final_target, s32 final_left, s32 final_top,
                                        s32 final_width, s32 final_height, s32 orig_width, s32 orig_height,
-                                       u32 target_width, u32 target_height)
+                                       s32 native_width, s32 native_height, u32 target_width, u32 target_height)
 {
   GL_SCOPE_FMT("GLSL Shader {}", m_name);
 
@@ -183,7 +178,7 @@ bool PostProcessing::GLSLShader::Apply(GPUTexture* input, GPUTexture* final_targ
   const u32 uniforms_size = GetUniformsSize();
   void* uniforms = g_gpu_device->MapUniformBuffer(uniforms_size);
   FillUniformBuffer(uniforms, input->GetWidth(), input->GetHeight(), final_left, final_top, final_width, final_height,
-                    target_width, target_height, orig_width, orig_height,
+                    target_width, target_height, orig_width, orig_height, native_width, native_height,
                     static_cast<float>(PostProcessing::GetTimer().GetTimeSeconds()));
   g_gpu_device->UnmapUniformBuffer(uniforms_size);
   g_gpu_device->Draw(3, 0);
@@ -407,42 +402,20 @@ static float4 o_col0;
 float4 Sample() { return texture(samp0, v_tex0); }
 float4 SampleLocation(float2 location) { return texture(samp0, location); }
 #define SampleOffset(offset) textureOffset(samp0, v_tex0, offset)
-float2 GetFragCoord()
-{
-  return gl_FragCoord.xy;
-}
-float2 GetWindowResolution()
-{
-  return window_resolution;
-}
-float2 GetResolution()
-{
-  return resolution;
-}
-float2 GetInvResolution()
-{
-  return rcp_resolution;
-}
-float2 GetCoordinates()
-{
-  return v_tex0;
-}
-float2 GetOriginalSize()
-{
-  return original_size;
-}
-float2 GetPaddedOriginalSize()
-{
-  return padded_original_size;
-}
-float GetTime()
-{
-  return time;
-}
-void SetOutput(float4 color)
-{
-  o_col0 = color;
-}
+float2 GetFragCoord() { return gl_FragCoord.xy; }
+float2 GetWindowResolution() { return window_resolution; }
+float2 GetResolution() { return resolution; }
+float2 GetInvResolution() { return rcp_resolution; }
+float2 GetCoordinates() { return v_tex0; }
+float2 GetOriginalSize() { return original_size; }
+float2 GetNativeSize() { return native_size; }
+float GetUpscaleMultiplier() { return upscale_multiplier; }
+float GetTime() { return time; }
+void SetOutput(float4 color) { o_col0 = color; }
+
+// Deprecated, only present for backwards compatibility.
+float2 GetPaddedOriginalSize() { return original_size; }
+
 #define GetOption(x) (x)
 #define OptionEnabled(x) ((x) != 0)
 )";
@@ -480,9 +453,9 @@ void PostProcessingGLSLShaderGen::WriteUniformBuffer(std::stringstream& ss, cons
   ss << "  float2 window_resolution;\n";
   ss << "  float2 rcp_window_resolution;\n";
   ss << "  float2 original_size;\n";
-  ss << "  float2 padded_original_size;\n";
+  ss << "  float2 native_size;\n";
   ss << "  float time;\n";
-  ss << "  float ubo_pad" << (pad_counter++) << ";\n";
+  ss << "  float upscale_multiplier;\n";
   ss << "\n";
 
   static constexpr std::array<const char*, PostProcessing::ShaderOption::MAX_VECTOR_COMPONENTS + 1> vector_size_suffix =

src/util/postprocessing_shader_glsl.h

@@ -24,7 +24,8 @@ public:
   bool ResizeOutput(GPUTexture::Format format, u32 width, u32 height) override;
   bool CompilePipeline(GPUTexture::Format format, u32 width, u32 height, ProgressCallback* progress) override;
   bool Apply(GPUTexture* input, GPUTexture* final_target, s32 final_left, s32 final_top, s32 final_width,
-             s32 final_height, s32 orig_width, s32 orig_height, u32 target_width, u32 target_height) override;
+             s32 final_height, s32 orig_width, s32 orig_height, s32 native_width, s32 native_height, u32 target_width,
+             u32 target_height) override;
 
 private:
   struct CommonUniforms
@@ -36,9 +37,9 @@ private:
     float window_resolution[2];
     float rcp_window_resolution[2];
     float original_size[2];
-    float padded_original_size[2];
+    float native_size[2];
+    float upscale_multiplier;
     float time;
-    float padding;
   };
 
   void LoadOptions();
@@ -46,7 +47,8 @@ private:
   u32 GetUniformsSize() const;
   void FillUniformBuffer(void* buffer, u32 texture_width, s32 texture_height, s32 texture_view_x, s32 texture_view_y,
                          s32 texture_view_width, s32 texture_view_height, u32 window_width, u32 window_height,
-                         s32 original_width, s32 original_height, float time) const;
+                         s32 original_width, s32 original_height, s32 native_width, s32 native_height,
+                         float time) const;
 
   std::string m_code;