From 181e64ca5a6c5de76606d673b584016b064ac0aa Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Tue, 5 Dec 2023 22:47:32 -0800
Subject: [PATCH 1/5] [Impeller] simplify binding logic further.

---
 impeller/compiler/code_gen_template.h         |  7 ++---
 impeller/core/resource_binder.h               |  6 +---
 impeller/core/shader_types.h                  | 28 +------------------
 .../entity/contents/checkerboard_contents.cc  |  1 +
 .../border_mask_blur_filter_contents.cc       |  1 +
 .../filters/color_matrix_filter_contents.cc   |  1 +
 ...rectional_gaussian_blur_filter_contents.cc |  1 +
 .../filters/gaussian_blur_filter_contents.cc  |  1 +
 .../filters/linear_to_srgb_filter_contents.cc |  1 +
 .../filters/morphology_filter_contents.cc     |  1 +
 .../filters/srgb_to_linear_filter_contents.cc |  1 +
 .../filters/yuv_to_rgb_filter_contents.cc     |  1 +
 .../contents/runtime_effect_contents.cc       |  5 ++--
 .../contents/test/contents_test_helpers.h     | 20 +++++++++----
 impeller/entity/contents/texture_contents.cc  |  2 +-
 impeller/entity/geometry/geometry.h           |  1 +
 .../backend/gles/buffer_bindings_gles.cc      | 12 ++++----
 .../backend/metal/compute_pass_mtl.mm         |  8 +++---
 .../renderer/backend/metal/render_pass_mtl.mm |  8 +++---
 .../backend/vulkan/binding_helpers_vk.cc      |  7 +++--
 .../backend/vulkan/compute_pass_vk.cc         |  2 +-
 .../renderer/backend/vulkan/render_pass_vk.cc |  2 +-
 impeller/renderer/command.cc                  | 21 ++++++--------
 impeller/renderer/command.h                   | 12 +++-----
 impeller/renderer/compute_command.cc          | 13 ++++-----
 impeller/renderer/compute_command.h           | 10 +------
 lib/gpu/render_pass.cc                        |  5 ++--
 27 files changed, 73 insertions(+), 105 deletions(-)

diff --git a/impeller/compiler/code_gen_template.h b/impeller/compiler/code_gen_template.h
index 1e73aee4a885a..4945155a420e5 100644
--- a/impeller/compiler/code_gen_template.h
+++ b/impeller/compiler/code_gen_template.h
@@ -118,12 +118,11 @@ struct {{camel_case(shader_name)}}{{camel_case(shader_stage)}}Shader {
   // ===========================================================================
 {% for sampled_image in sampled_images %}
 
-  static constexpr auto kResource{{camel_case(sampled_image.name)}} = SampledImageSlot { // {{sampled_image.name}}
+  static constexpr auto kResource{{camel_case(sampled_image.name)}} = ShaderUniformSlot { // {{sampled_image.name}}
     "{{sampled_image.name}}",      // name
-    {{sampled_image.ext_res_0}}u,  // texture
-    {{sampled_image.ext_res_1}}u,  // sampler
-    {{sampled_image.binding}}u,    // binding
+    {{sampled_image.ext_res_0}}u,  // ext_res_0
     {{sampled_image.set}}u,        // set
+    {{sampled_image.binding}}u,    // binding
   };
   static ShaderMetadata kMetadata{{camel_case(sampled_image.name)}};
 {% endfor %}
diff --git a/impeller/core/resource_binder.h b/impeller/core/resource_binder.h
index 18b9d4c250121..eb9054c1ff69a 100644
--- a/impeller/core/resource_binder.h
+++ b/impeller/core/resource_binder.h
@@ -4,12 +4,8 @@
 
 #pragma once
 
-#include <map>
 #include <memory>
-#include <optional>
-#include <string>
 
-#include "flutter/fml/logging.h"
 #include "impeller/core/buffer_view.h"
 #include "impeller/core/formats.h"
 #include "impeller/core/sampler.h"
@@ -32,7 +28,7 @@ struct ResourceBinder {
                             BufferView view) = 0;
 
   virtual bool BindResource(ShaderStage stage,
-                            const SampledImageSlot& slot,
+                            const ShaderUniformSlot& slot,
                             const ShaderMetadata& metadata,
                             std::shared_ptr<const Texture> texture,
                             std::shared_ptr<const Sampler> sampler) = 0;
diff --git a/impeller/core/shader_types.h b/impeller/core/shader_types.h
index 425792d1ac7c0..3003f2f7569f2 100644
--- a/impeller/core/shader_types.h
+++ b/impeller/core/shader_types.h
@@ -73,7 +73,7 @@ struct ShaderMetadata {
   std::vector<ShaderStructMemberMetadata> members;
 };
 
-/// @brief Metadata required to bind a buffer.
+/// @brief Metadata required to bind a buffer or texture/sampler.
 ///
 /// OpenGL binding requires the usage of the separate shader metadata struct.
 struct ShaderUniformSlot {
@@ -131,32 +131,6 @@ struct ShaderStageBufferLayout {
   }
 };
 
-/// @brief Metadata required to bind a texture and sampler.
-///
-/// OpenGL binding requires the usage of the separate shader metadata struct.
-struct SampledImageSlot {
-  /// @brief The name of the texture slot.
-  const char* name;
-
-  /// @brief This value is `ext_res_0`, the Metal binding value for the texture.
-  size_t texture_index;
-
-  /// @brief This value is `ext_res_1`, the Metal binding value for the sampler.
-  ///
-  /// Since only combined texture and samplers are used, this index is unused.
-  size_t sampler_index;
-
-  /// @brief The Vulkan binding value for a combined texture and sampler.
-  size_t binding;
-
-  /// @brief The Vulkan descriptor set index.
-  size_t set;
-
-  constexpr bool HasTexture() const { return texture_index < 32u; }
-
-  constexpr bool HasSampler() const { return sampler_index < 32u; }
-};
-
 enum class DescriptorType {
   kUniformBuffer,
   kStorageBuffer,
diff --git a/impeller/entity/contents/checkerboard_contents.cc b/impeller/entity/contents/checkerboard_contents.cc
index debb65da9cbda..f58bb38850891 100644
--- a/impeller/entity/contents/checkerboard_contents.cc
+++ b/impeller/entity/contents/checkerboard_contents.cc
@@ -10,6 +10,7 @@
 #include "impeller/entity/contents/content_context.h"
 #include "impeller/renderer/command.h"
 #include "impeller/renderer/render_pass.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/filters/border_mask_blur_filter_contents.cc b/impeller/entity/contents/filters/border_mask_blur_filter_contents.cc
index da21b9134940a..5e41befaa7039 100644
--- a/impeller/entity/contents/filters/border_mask_blur_filter_contents.cc
+++ b/impeller/entity/contents/filters/border_mask_blur_filter_contents.cc
@@ -9,6 +9,7 @@
 #include "impeller/entity/contents/contents.h"
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/filters/color_matrix_filter_contents.cc b/impeller/entity/contents/filters/color_matrix_filter_contents.cc
index 2c159c803aac9..2ce6526169f3e 100644
--- a/impeller/entity/contents/filters/color_matrix_filter_contents.cc
+++ b/impeller/entity/contents/filters/color_matrix_filter_contents.cc
@@ -14,6 +14,7 @@
 #include "impeller/geometry/vector.h"
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents.cc b/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents.cc
index cbda25181664f..d9965ded5bd46 100644
--- a/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents.cc
+++ b/impeller/entity/contents/filters/directional_gaussian_blur_filter_contents.cc
@@ -20,6 +20,7 @@
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/render_target.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/filters/gaussian_blur_filter_contents.cc b/impeller/entity/contents/filters/gaussian_blur_filter_contents.cc
index dd1d0256a921d..61ac31f3d3162 100644
--- a/impeller/entity/contents/filters/gaussian_blur_filter_contents.cc
+++ b/impeller/entity/contents/filters/gaussian_blur_filter_contents.cc
@@ -10,6 +10,7 @@
 #include "impeller/renderer/command.h"
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/filters/linear_to_srgb_filter_contents.cc b/impeller/entity/contents/filters/linear_to_srgb_filter_contents.cc
index 64f13cdddf6a3..2bad955bf0416 100644
--- a/impeller/entity/contents/filters/linear_to_srgb_filter_contents.cc
+++ b/impeller/entity/contents/filters/linear_to_srgb_filter_contents.cc
@@ -11,6 +11,7 @@
 #include "impeller/geometry/vector.h"
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/filters/morphology_filter_contents.cc b/impeller/entity/contents/filters/morphology_filter_contents.cc
index 2aa8290830cd5..086dc000e8666 100644
--- a/impeller/entity/contents/filters/morphology_filter_contents.cc
+++ b/impeller/entity/contents/filters/morphology_filter_contents.cc
@@ -11,6 +11,7 @@
 #include "impeller/entity/contents/contents.h"
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/filters/srgb_to_linear_filter_contents.cc b/impeller/entity/contents/filters/srgb_to_linear_filter_contents.cc
index 38c6a2fe2842f..4488b5f21b5f7 100644
--- a/impeller/entity/contents/filters/srgb_to_linear_filter_contents.cc
+++ b/impeller/entity/contents/filters/srgb_to_linear_filter_contents.cc
@@ -11,6 +11,7 @@
 #include "impeller/geometry/vector.h"
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/filters/yuv_to_rgb_filter_contents.cc b/impeller/entity/contents/filters/yuv_to_rgb_filter_contents.cc
index 21ddf7ee82bf2..99c5ac545ee4b 100644
--- a/impeller/entity/contents/filters/yuv_to_rgb_filter_contents.cc
+++ b/impeller/entity/contents/filters/yuv_to_rgb_filter_contents.cc
@@ -10,6 +10,7 @@
 #include "impeller/geometry/matrix.h"
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/contents/runtime_effect_contents.cc b/impeller/entity/contents/runtime_effect_contents.cc
index 91c18a3b7e0ce..9c4e163d95c38 100644
--- a/impeller/entity/contents/runtime_effect_contents.cc
+++ b/impeller/entity/contents/runtime_effect_contents.cc
@@ -238,10 +238,9 @@ bool RuntimeEffectContents::Render(const ContentContext& renderer,
         auto sampler =
             context->GetSamplerLibrary()->GetSampler(input.sampler_descriptor);
 
-        SampledImageSlot image_slot;
+        ShaderUniformSlot image_slot;
         image_slot.name = uniform.name.c_str();
-        image_slot.texture_index = uniform.location - minimum_sampler_index;
-        image_slot.sampler_index = uniform.location - minimum_sampler_index;
+        image_slot.ext_res_0 = uniform.location - minimum_sampler_index;
         cmd.BindResource(ShaderStage::kFragment, image_slot, metadata,
                          input.texture, sampler);
 
diff --git a/impeller/entity/contents/test/contents_test_helpers.h b/impeller/entity/contents/test/contents_test_helpers.h
index 6d3803ef9969d..e65b5636ef8d5 100644
--- a/impeller/entity/contents/test/contents_test_helpers.h
+++ b/impeller/entity/contents/test/contents_test_helpers.h
@@ -11,26 +11,34 @@ namespace impeller {
 /// @brief Retrieve the [VertInfo] struct data from the provided [command].
 template <typename T>
 typename T::VertInfo* GetVertInfo(const Command& command) {
-  auto resource = command.vertex_bindings.buffers.find(0u);
+  auto resource = std::find_if(command.vertex_bindings.buffers.begin(),
+                               command.vertex_bindings.buffers.end(),
+                               [](const BufferAndUniformSlot& data) {
+                                 return data.slot.ext_res_0 == 0u;
+                               });
   if (resource == command.vertex_bindings.buffers.end()) {
     return nullptr;
   }
 
-  auto data = (resource->second.view.resource.contents +
-               resource->second.view.resource.range.offset);
+  auto data =
+      (resource->view.resource.contents + resource->view.resource.range.offset);
   return reinterpret_cast<typename T::VertInfo*>(data);
 }
 
 /// @brief Retrieve the [FragInfo] struct data from the provided [command].
 template <typename T>
 typename T::FragInfo* GetFragInfo(const Command& command) {
-  auto resource = command.fragment_bindings.buffers.find(0u);
+  auto resource = std::find_if(command.fragment_bindings.buffers.begin(),
+                               command.fragment_bindings.buffers.end(),
+                               [](const BufferAndUniformSlot& data) {
+                                 return data.slot.ext_res_0 == 0u;
+                               });
   if (resource == command.fragment_bindings.buffers.end()) {
     return nullptr;
   }
 
-  auto data = (resource->second.view.resource.contents +
-               resource->second.view.resource.range.offset);
+  auto data =
+      (resource->view.resource.contents + resource->view.resource.range.offset);
   return reinterpret_cast<typename T::FragInfo*>(data);
 }
 
diff --git a/impeller/entity/contents/texture_contents.cc b/impeller/entity/contents/texture_contents.cc
index 9b9614aaf04f0..3ffd92f6b7a40 100644
--- a/impeller/entity/contents/texture_contents.cc
+++ b/impeller/entity/contents/texture_contents.cc
@@ -15,9 +15,9 @@
 #include "impeller/entity/texture_fill.vert.h"
 #include "impeller/entity/texture_fill_external.frag.h"
 #include "impeller/geometry/constants.h"
-#include "impeller/geometry/path_builder.h"
 #include "impeller/renderer/render_pass.h"
 #include "impeller/renderer/sampler_library.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/entity/geometry/geometry.h b/impeller/entity/geometry/geometry.h
index f41503551e0f6..de2f0e40c3271 100644
--- a/impeller/entity/geometry/geometry.h
+++ b/impeller/entity/geometry/geometry.h
@@ -10,6 +10,7 @@
 #include "impeller/entity/entity.h"
 #include "impeller/entity/texture_fill.vert.h"
 #include "impeller/renderer/render_pass.h"
+#include "impeller/renderer/vertex_buffer_builder.h"
 
 namespace impeller {
 
diff --git a/impeller/renderer/backend/gles/buffer_bindings_gles.cc b/impeller/renderer/backend/gles/buffer_bindings_gles.cc
index c96c4a5a04ac9..696ab62b42b35 100644
--- a/impeller/renderer/backend/gles/buffer_bindings_gles.cc
+++ b/impeller/renderer/backend/gles/buffer_bindings_gles.cc
@@ -145,12 +145,12 @@ bool BufferBindingsGLES::BindUniformData(const ProcTableGLES& gl,
                                          const Bindings& vertex_bindings,
                                          const Bindings& fragment_bindings) {
   for (const auto& buffer : vertex_bindings.buffers) {
-    if (!BindUniformBuffer(gl, transients_allocator, buffer.second.view)) {
+    if (!BindUniformBuffer(gl, transients_allocator, buffer.view)) {
       return false;
     }
   }
   for (const auto& buffer : fragment_bindings.buffers) {
-    if (!BindUniformBuffer(gl, transients_allocator, buffer.second.view)) {
+    if (!BindUniformBuffer(gl, transients_allocator, buffer.view)) {
       return false;
     }
   }
@@ -345,13 +345,13 @@ std::optional<size_t> BufferBindingsGLES::BindTextures(
     size_t unit_start_index) {
   size_t active_index = unit_start_index;
   for (const auto& data : bindings.sampled_images) {
-    const auto& texture_gles = TextureGLES::Cast(*data.second.texture.resource);
-    if (data.second.texture.GetMetadata() == nullptr) {
+    const auto& texture_gles = TextureGLES::Cast(*data.texture.resource);
+    if (data.texture.GetMetadata() == nullptr) {
       VALIDATION_LOG << "No metadata found for texture binding.";
       return std::nullopt;
     }
 
-    auto location = ComputeTextureLocation(data.second.texture.GetMetadata());
+    auto location = ComputeTextureLocation(data.texture.GetMetadata());
     if (location == -1) {
       return std::nullopt;
     }
@@ -377,7 +377,7 @@ std::optional<size_t> BufferBindingsGLES::BindTextures(
     /// If there is a sampler for the texture at the same index, configure the
     /// bound texture using that sampler.
     ///
-    const auto& sampler_gles = SamplerGLES::Cast(*data.second.sampler);
+    const auto& sampler_gles = SamplerGLES::Cast(*data.sampler);
     if (!sampler_gles.ConfigureBoundTexture(texture_gles, gl)) {
       return std::nullopt;
     }
diff --git a/impeller/renderer/backend/metal/compute_pass_mtl.mm b/impeller/renderer/backend/metal/compute_pass_mtl.mm
index a55ec4fe07f60..a13eee599dbb0 100644
--- a/impeller/renderer/backend/metal/compute_pass_mtl.mm
+++ b/impeller/renderer/backend/metal/compute_pass_mtl.mm
@@ -224,15 +224,15 @@ static bool Bind(ComputePassBindingsCache& pass,
             .GetMTLComputePipelineState());
 
     for (const auto& buffer : command.bindings.buffers) {
-      if (!Bind(pass_bindings, *allocator, buffer.first,
-                buffer.second.view.resource)) {
+      if (!Bind(pass_bindings, *allocator, buffer.slot.ext_res_0,
+                buffer.view.resource)) {
         return false;
       }
     }
 
     for (const auto& data : command.bindings.sampled_images) {
-      if (!Bind(pass_bindings, data.first, *data.second.sampler,
-                *data.second.texture.resource)) {
+      if (!Bind(pass_bindings, data.slot.ext_res_0, *data.sampler,
+                *data.texture.resource)) {
         return false;
       }
     }
diff --git a/impeller/renderer/backend/metal/render_pass_mtl.mm b/impeller/renderer/backend/metal/render_pass_mtl.mm
index f4fc37f0dfaf7..8fe42989f6f3c 100644
--- a/impeller/renderer/backend/metal/render_pass_mtl.mm
+++ b/impeller/renderer/backend/metal/render_pass_mtl.mm
@@ -409,14 +409,14 @@ static bool Bind(PassBindingsCache& pass,
                                   const Bindings& bindings,
                                   ShaderStage stage) -> bool {
     for (const auto& buffer : bindings.buffers) {
-      if (!Bind(pass_bindings, *allocator, stage, buffer.first,
-                buffer.second.view.resource)) {
+      if (!Bind(pass_bindings, *allocator, stage, buffer.slot.ext_res_0,
+                buffer.view.resource)) {
         return false;
       }
     }
     for (const auto& data : bindings.sampled_images) {
-      if (!Bind(pass_bindings, stage, data.first, *data.second.sampler,
-                *data.second.texture.resource)) {
+      if (!Bind(pass_bindings, stage, data.slot.ext_res_0, *data.sampler,
+                *data.texture.resource)) {
         return false;
       }
     }
diff --git a/impeller/renderer/backend/vulkan/binding_helpers_vk.cc b/impeller/renderer/backend/vulkan/binding_helpers_vk.cc
index d029a76f6d137..10ee695a189a7 100644
--- a/impeller/renderer/backend/vulkan/binding_helpers_vk.cc
+++ b/impeller/renderer/backend/vulkan/binding_helpers_vk.cc
@@ -4,6 +4,7 @@
 
 #include "impeller/renderer/backend/vulkan/binding_helpers_vk.h"
 #include "fml/status.h"
+#include "impeller/core/shader_types.h"
 #include "impeller/renderer/backend/vulkan/command_buffer_vk.h"
 #include "impeller/renderer/backend/vulkan/command_encoder_vk.h"
 #include "impeller/renderer/backend/vulkan/command_pool_vk.h"
@@ -28,7 +29,7 @@ static bool BindImages(const Bindings& bindings,
                        vk::DescriptorSet& vk_desc_set,
                        std::vector<vk::DescriptorImageInfo>& images,
                        std::vector<vk::WriteDescriptorSet>& writes) {
-  for (const auto& [index, data] : bindings.sampled_images) {
+  for (const auto& data : bindings.sampled_images) {
     auto texture = data.texture.resource;
     const auto& texture_vk = TextureVK::Cast(*texture);
     const SamplerVK& sampler = SamplerVK::Cast(*data.sampler);
@@ -38,7 +39,7 @@ static bool BindImages(const Bindings& bindings,
       return false;
     }
 
-    const SampledImageSlot& slot = data.slot;
+    const ShaderUniformSlot& slot = data.slot;
 
     vk::DescriptorImageInfo image_info;
     image_info.imageLayout = vk::ImageLayout::eShaderReadOnlyOptimal;
@@ -66,7 +67,7 @@ static bool BindBuffers(const Bindings& bindings,
                         const std::vector<DescriptorSetLayout>& desc_set,
                         std::vector<vk::DescriptorBufferInfo>& buffers,
                         std::vector<vk::WriteDescriptorSet>& writes) {
-  for (const auto& [buffer_index, data] : bindings.buffers) {
+  for (const auto& data : bindings.buffers) {
     const auto& buffer_view = data.view.resource.buffer;
 
     auto device_buffer = buffer_view->GetDeviceBuffer(allocator);
diff --git a/impeller/renderer/backend/vulkan/compute_pass_vk.cc b/impeller/renderer/backend/vulkan/compute_pass_vk.cc
index 43d1ce34f7590..56bc71cd782a0 100644
--- a/impeller/renderer/backend/vulkan/compute_pass_vk.cc
+++ b/impeller/renderer/backend/vulkan/compute_pass_vk.cc
@@ -43,7 +43,7 @@ static bool UpdateBindingLayouts(const Bindings& bindings,
 
   barrier.new_layout = vk::ImageLayout::eShaderReadOnlyOptimal;
 
-  for (const auto& [_, data] : bindings.sampled_images) {
+  for (const auto& data : bindings.sampled_images) {
     if (!TextureVK::Cast(*data.texture.resource).SetLayout(barrier)) {
       return false;
     }
diff --git a/impeller/renderer/backend/vulkan/render_pass_vk.cc b/impeller/renderer/backend/vulkan/render_pass_vk.cc
index e5d313748881f..9b624155f9b13 100644
--- a/impeller/renderer/backend/vulkan/render_pass_vk.cc
+++ b/impeller/renderer/backend/vulkan/render_pass_vk.cc
@@ -315,7 +315,7 @@ static bool UpdateBindingLayouts(const Bindings& bindings,
 
   barrier.new_layout = vk::ImageLayout::eShaderReadOnlyOptimal;
 
-  for (const auto& [_, data] : bindings.sampled_images) {
+  for (const auto& data : bindings.sampled_images) {
     if (!TextureVK::Cast(*data.texture.resource).SetLayout(barrier)) {
       return false;
     }
diff --git a/impeller/renderer/command.cc b/impeller/renderer/command.cc
index ed7fc0bc4960f..c40350d54a24b 100644
--- a/impeller/renderer/command.cc
+++ b/impeller/renderer/command.cc
@@ -49,12 +49,12 @@ bool Command::DoBindResource(ShaderStage stage,
 
   switch (stage) {
     case ShaderStage::kVertex:
-      vertex_bindings.buffers[slot.ext_res_0] = {
-          .slot = slot, .view = BufferResource(metadata, std::move(view))};
+      vertex_bindings.buffers.emplace_back(BufferAndUniformSlot{
+          .slot = slot, .view = BufferResource(metadata, std::move(view))});
       return true;
     case ShaderStage::kFragment:
-      fragment_bindings.buffers[slot.ext_res_0] = {
-          .slot = slot, .view = BufferResource(metadata, std::move(view))};
+      fragment_bindings.buffers.emplace_back(BufferAndUniformSlot{
+          .slot = slot, .view = BufferResource(metadata, std::move(view))});
       return true;
     case ShaderStage::kCompute:
       VALIDATION_LOG << "Use ComputeCommands for compute shader stages.";
@@ -66,7 +66,7 @@ bool Command::DoBindResource(ShaderStage stage,
 }
 
 bool Command::BindResource(ShaderStage stage,
-                           const SampledImageSlot& slot,
+                           const ShaderUniformSlot& slot,
                            const ShaderMetadata& metadata,
                            std::shared_ptr<const Texture> texture,
                            std::shared_ptr<const Sampler> sampler) {
@@ -76,24 +76,21 @@ bool Command::BindResource(ShaderStage stage,
   if (!texture || !texture->IsValid()) {
     return false;
   }
-  if (!slot.HasSampler() || !slot.HasTexture()) {
-    return true;
-  }
 
   switch (stage) {
     case ShaderStage::kVertex:
-      vertex_bindings.sampled_images[slot.sampler_index] = TextureAndSampler{
+      vertex_bindings.sampled_images.emplace_back(TextureAndSampler{
           .slot = slot,
           .texture = {&metadata, std::move(texture)},
           .sampler = std::move(sampler),
-      };
+      });
       return true;
     case ShaderStage::kFragment:
-      fragment_bindings.sampled_images[slot.sampler_index] = TextureAndSampler{
+      fragment_bindings.sampled_images.emplace_back(TextureAndSampler{
           .slot = slot,
           .texture = {&metadata, std::move(texture)},
           .sampler = std::move(sampler),
-      };
+      });
       return true;
     case ShaderStage::kCompute:
       VALIDATION_LOG << "Use ComputeCommands for compute shader stages.";
diff --git a/impeller/renderer/command.h b/impeller/renderer/command.h
index d64215d134a43..8f041d5086871 100644
--- a/impeller/renderer/command.h
+++ b/impeller/renderer/command.h
@@ -10,8 +10,6 @@
 #include <optional>
 #include <string>
 
-#include "flutter/fml/logging.h"
-#include "flutter/fml/macros.h"
 #include "impeller/core/buffer_view.h"
 #include "impeller/core/formats.h"
 #include "impeller/core/resource_binder.h"
@@ -21,8 +19,6 @@
 #include "impeller/core/vertex_buffer.h"
 #include "impeller/geometry/rect.h"
 #include "impeller/renderer/pipeline.h"
-#include "impeller/renderer/vertex_buffer_builder.h"
-#include "impeller/tessellator/tessellator.h"
 
 namespace impeller {
 
@@ -63,7 +59,7 @@ using TextureResource = Resource<std::shared_ptr<const Texture>>;
 
 /// @brief combines the texture, sampler and sampler slot information.
 struct TextureAndSampler {
-  SampledImageSlot slot;
+  ShaderUniformSlot slot;
   TextureResource texture;
   std::shared_ptr<const Sampler> sampler;
 };
@@ -75,8 +71,8 @@ struct BufferAndUniformSlot {
 };
 
 struct Bindings {
-  std::map<size_t, TextureAndSampler> sampled_images;
-  std::map<size_t, BufferAndUniformSlot> buffers;
+  std::vector<TextureAndSampler> sampled_images;
+  std::vector<BufferAndUniformSlot> buffers;
 };
 
 //------------------------------------------------------------------------------
@@ -177,7 +173,7 @@ struct Command : public ResourceBinder {
 
   // |ResourceBinder|
   bool BindResource(ShaderStage stage,
-                    const SampledImageSlot& slot,
+                    const ShaderUniformSlot& slot,
                     const ShaderMetadata& metadata,
                     std::shared_ptr<const Texture> texture,
                     std::shared_ptr<const Sampler> sampler) override;
diff --git a/impeller/renderer/compute_command.cc b/impeller/renderer/compute_command.cc
index 78b9fb99ec004..62f2491b4f456 100644
--- a/impeller/renderer/compute_command.cc
+++ b/impeller/renderer/compute_command.cc
@@ -23,13 +23,13 @@ bool ComputeCommand::BindResource(ShaderStage stage,
     return false;
   }
 
-  bindings.buffers[slot.ext_res_0] = {.slot = slot,
-                                      .view = {&metadata, std::move(view)}};
+  bindings.buffers.emplace_back(
+      BufferAndUniformSlot{.slot = slot, .view = {&metadata, std::move(view)}});
   return true;
 }
 
 bool ComputeCommand::BindResource(ShaderStage stage,
-                                  const SampledImageSlot& slot,
+                                  const ShaderUniformSlot& slot,
                                   const ShaderMetadata& metadata,
                                   std::shared_ptr<const Texture> texture,
                                   std::shared_ptr<const Sampler> sampler) {
@@ -43,15 +43,12 @@ bool ComputeCommand::BindResource(ShaderStage stage,
   if (!texture || !texture->IsValid()) {
     return false;
   }
-  if (!slot.HasSampler() || !slot.HasTexture()) {
-    return true;
-  }
 
-  bindings.sampled_images[slot.sampler_index] = TextureAndSampler{
+  bindings.sampled_images.emplace_back(TextureAndSampler{
       .slot = slot,
       .texture = {&metadata, std::move(texture)},
       .sampler = std::move(sampler),
-  };
+  });
 
   return false;
 }
diff --git a/impeller/renderer/compute_command.h b/impeller/renderer/compute_command.h
index f537b37e62c20..511590ab31690 100644
--- a/impeller/renderer/compute_command.h
+++ b/impeller/renderer/compute_command.h
@@ -4,26 +4,18 @@
 
 #pragma once
 
-#include <map>
 #include <memory>
-#include <optional>
 #include <string>
 
-#include "flutter/fml/logging.h"
-#include "flutter/fml/macros.h"
 #include "impeller/core/buffer_view.h"
 #include "impeller/core/formats.h"
 #include "impeller/core/resource_binder.h"
 #include "impeller/core/sampler.h"
 #include "impeller/core/shader_types.h"
 #include "impeller/core/texture.h"
-#include "impeller/core/vertex_buffer.h"
-#include "impeller/geometry/rect.h"
 #include "impeller/renderer/command.h"
 #include "impeller/renderer/compute_pipeline_descriptor.h"
 #include "impeller/renderer/pipeline.h"
-#include "impeller/renderer/vertex_buffer_builder.h"
-#include "impeller/tessellator/tessellator.h"
 
 namespace impeller {
 
@@ -66,7 +58,7 @@ struct ComputeCommand : public ResourceBinder {
 
   // |ResourceBinder|
   bool BindResource(ShaderStage stage,
-                    const SampledImageSlot& slot,
+                    const ShaderUniformSlot& slot,
                     const ShaderMetadata& metadata,
                     std::shared_ptr<const Texture> texture,
                     std::shared_ptr<const Sampler> sampler) override;
diff --git a/lib/gpu/render_pass.cc b/lib/gpu/render_pass.cc
index 24e01f2ad2f12..4be78f80dc6d9 100644
--- a/lib/gpu/render_pass.cc
+++ b/lib/gpu/render_pass.cc
@@ -384,9 +384,8 @@ bool InternalFlutterGpu_RenderPass_BindTexture(
   auto sampler = wrapper->GetContext().lock()->GetSamplerLibrary()->GetSampler(
       sampler_desc);
 
-  impeller::SampledImageSlot image_slot;
-  image_slot.texture_index = slot_id;
-  image_slot.sampler_index = slot_id;
+  impeller::ShaderUniformSlot image_slot;
+  image_slot.ext_res_0 = slot_id;
   return command.BindResource(flutter::gpu::ToImpellerShaderStage(stage),
                               image_slot, metadata, texture->GetTexture(),
                               sampler);

From 3d2c44d5513c02cbcd9af80fc612e05d32c1c563 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 6 Dec 2023 09:58:03 -0800
Subject: [PATCH 2/5] Add back sampled image slot.

---
 impeller/compiler/code_gen_template.h         |  2 +-
 impeller/core/resource_binder.h               |  2 +-
 impeller/core/shader_types.h                  | 19 ++++++++++++++++++-
 .../contents/runtime_effect_contents.cc       |  4 ++--
 .../backend/metal/compute_pass_mtl.mm         |  9 +++++----
 .../renderer/backend/metal/render_pass_mtl.mm |  7 ++++---
 .../backend/vulkan/binding_helpers_vk.cc      |  6 +++---
 .../backend/vulkan/compute_pass_vk.cc         |  5 +++--
 impeller/renderer/command.cc                  |  2 +-
 impeller/renderer/command.h                   |  4 ++--
 impeller/renderer/compute_command.cc          |  2 +-
 impeller/renderer/compute_command.h           |  2 +-
 lib/gpu/render_pass.cc                        |  4 ++--
 13 files changed, 44 insertions(+), 24 deletions(-)

diff --git a/impeller/compiler/code_gen_template.h b/impeller/compiler/code_gen_template.h
index 4945155a420e5..7927c71d2952c 100644
--- a/impeller/compiler/code_gen_template.h
+++ b/impeller/compiler/code_gen_template.h
@@ -118,7 +118,7 @@ struct {{camel_case(shader_name)}}{{camel_case(shader_stage)}}Shader {
   // ===========================================================================
 {% for sampled_image in sampled_images %}
 
-  static constexpr auto kResource{{camel_case(sampled_image.name)}} = ShaderUniformSlot { // {{sampled_image.name}}
+  static constexpr auto kResource{{camel_case(sampled_image.name)}} = SampledImageSlot { // {{sampled_image.name}}
     "{{sampled_image.name}}",      // name
     {{sampled_image.ext_res_0}}u,  // ext_res_0
     {{sampled_image.set}}u,        // set
diff --git a/impeller/core/resource_binder.h b/impeller/core/resource_binder.h
index eb9054c1ff69a..a3bbb532f9522 100644
--- a/impeller/core/resource_binder.h
+++ b/impeller/core/resource_binder.h
@@ -28,7 +28,7 @@ struct ResourceBinder {
                             BufferView view) = 0;
 
   virtual bool BindResource(ShaderStage stage,
-                            const ShaderUniformSlot& slot,
+                            const SampledImageSlot& slot,
                             const ShaderMetadata& metadata,
                             std::shared_ptr<const Texture> texture,
                             std::shared_ptr<const Sampler> sampler) = 0;
diff --git a/impeller/core/shader_types.h b/impeller/core/shader_types.h
index 3003f2f7569f2..83fd120baf7ba 100644
--- a/impeller/core/shader_types.h
+++ b/impeller/core/shader_types.h
@@ -73,7 +73,7 @@ struct ShaderMetadata {
   std::vector<ShaderStructMemberMetadata> members;
 };
 
-/// @brief Metadata required to bind a buffer or texture/sampler.
+/// @brief Metadata required to bind a buffer.
 ///
 /// OpenGL binding requires the usage of the separate shader metadata struct.
 struct ShaderUniformSlot {
@@ -90,6 +90,23 @@ struct ShaderUniformSlot {
   size_t binding;
 };
 
+/// @brief Metadata required to bind a combined texture and sampler.
+///
+/// OpenGL binding requires the usage of the separate shader metadata struct.
+struct SampledImageSlot {
+  /// @brief The name of the uniform slot.
+  const char* name;
+
+  /// @brief `ext_res_0` is the Metal binding value.
+  size_t texture_index;
+
+  /// @brief The Vulkan descriptor set index.
+  size_t set;
+
+  /// @brief The Vulkan binding value.
+  size_t binding;
+};
+
 struct ShaderStageIOSlot {
   const char* name;
   size_t location;
diff --git a/impeller/entity/contents/runtime_effect_contents.cc b/impeller/entity/contents/runtime_effect_contents.cc
index 9c4e163d95c38..82ad3508ff274 100644
--- a/impeller/entity/contents/runtime_effect_contents.cc
+++ b/impeller/entity/contents/runtime_effect_contents.cc
@@ -238,9 +238,9 @@ bool RuntimeEffectContents::Render(const ContentContext& renderer,
         auto sampler =
             context->GetSamplerLibrary()->GetSampler(input.sampler_descriptor);
 
-        ShaderUniformSlot image_slot;
+        SampledImageSlot image_slot;
         image_slot.name = uniform.name.c_str();
-        image_slot.ext_res_0 = uniform.location - minimum_sampler_index;
+        image_slot.texture_index = uniform.location - minimum_sampler_index;
         cmd.BindResource(ShaderStage::kFragment, image_slot, metadata,
                          input.texture, sampler);
 
diff --git a/impeller/renderer/backend/metal/compute_pass_mtl.mm b/impeller/renderer/backend/metal/compute_pass_mtl.mm
index a13eee599dbb0..0cbce56c48c31 100644
--- a/impeller/renderer/backend/metal/compute_pass_mtl.mm
+++ b/impeller/renderer/backend/metal/compute_pass_mtl.mm
@@ -21,6 +21,7 @@
 #include "impeller/renderer/backend/metal/formats_mtl.h"
 #include "impeller/renderer/backend/metal/sampler_mtl.h"
 #include "impeller/renderer/backend/metal/texture_mtl.h"
+#include "impeller/renderer/command.h"
 #include "impeller/renderer/compute_command.h"
 
 namespace impeller {
@@ -209,7 +210,7 @@ static bool Bind(ComputePassBindingsCache& pass,
   ComputePassBindingsCache pass_bindings(encoder);
 
   fml::closure pop_debug_marker = [encoder]() { [encoder popDebugGroup]; };
-  for (const auto& command : commands_) {
+  for (const ComputeCommand& command : commands_) {
 #ifdef IMPELLER_DEBUG
     fml::ScopedCleanupClosure auto_pop_debug_marker(pop_debug_marker);
     if (!command.label.empty()) {
@@ -223,15 +224,15 @@ static bool Bind(ComputePassBindingsCache& pass,
         ComputePipelineMTL::Cast(*command.pipeline)
             .GetMTLComputePipelineState());
 
-    for (const auto& buffer : command.bindings.buffers) {
+    for (const BufferAndUniformSlot& buffer : command.bindings.buffers) {
       if (!Bind(pass_bindings, *allocator, buffer.slot.ext_res_0,
                 buffer.view.resource)) {
         return false;
       }
     }
 
-    for (const auto& data : command.bindings.sampled_images) {
-      if (!Bind(pass_bindings, data.slot.ext_res_0, *data.sampler,
+    for (const TextureAndSampler& data : command.bindings.sampled_images) {
+      if (!Bind(pass_bindings, data.slot.texture_index, *data.sampler,
                 *data.texture.resource)) {
         return false;
       }
diff --git a/impeller/renderer/backend/metal/render_pass_mtl.mm b/impeller/renderer/backend/metal/render_pass_mtl.mm
index 8fe42989f6f3c..d313ca2b0f953 100644
--- a/impeller/renderer/backend/metal/render_pass_mtl.mm
+++ b/impeller/renderer/backend/metal/render_pass_mtl.mm
@@ -18,6 +18,7 @@
 #include "impeller/renderer/backend/metal/pipeline_mtl.h"
 #include "impeller/renderer/backend/metal/sampler_mtl.h"
 #include "impeller/renderer/backend/metal/texture_mtl.h"
+#include "impeller/renderer/command.h"
 #include "impeller/renderer/vertex_descriptor.h"
 
 namespace impeller {
@@ -408,14 +409,14 @@ static bool Bind(PassBindingsCache& pass,
   auto bind_stage_resources = [&allocator, &pass_bindings](
                                   const Bindings& bindings,
                                   ShaderStage stage) -> bool {
-    for (const auto& buffer : bindings.buffers) {
+    for (const BufferAndUniformSlot& buffer : bindings.buffers) {
       if (!Bind(pass_bindings, *allocator, stage, buffer.slot.ext_res_0,
                 buffer.view.resource)) {
         return false;
       }
     }
-    for (const auto& data : bindings.sampled_images) {
-      if (!Bind(pass_bindings, stage, data.slot.ext_res_0, *data.sampler,
+    for (const TextureAndSampler& data : bindings.sampled_images) {
+      if (!Bind(pass_bindings, stage, data.slot.texture_index, *data.sampler,
                 *data.texture.resource)) {
         return false;
       }
diff --git a/impeller/renderer/backend/vulkan/binding_helpers_vk.cc b/impeller/renderer/backend/vulkan/binding_helpers_vk.cc
index 10ee695a189a7..676980689ce65 100644
--- a/impeller/renderer/backend/vulkan/binding_helpers_vk.cc
+++ b/impeller/renderer/backend/vulkan/binding_helpers_vk.cc
@@ -29,7 +29,7 @@ static bool BindImages(const Bindings& bindings,
                        vk::DescriptorSet& vk_desc_set,
                        std::vector<vk::DescriptorImageInfo>& images,
                        std::vector<vk::WriteDescriptorSet>& writes) {
-  for (const auto& data : bindings.sampled_images) {
+  for (const TextureAndSampler& data : bindings.sampled_images) {
     auto texture = data.texture.resource;
     const auto& texture_vk = TextureVK::Cast(*texture);
     const SamplerVK& sampler = SamplerVK::Cast(*data.sampler);
@@ -39,7 +39,7 @@ static bool BindImages(const Bindings& bindings,
       return false;
     }
 
-    const ShaderUniformSlot& slot = data.slot;
+    const SampledImageSlot& slot = data.slot;
 
     vk::DescriptorImageInfo image_info;
     image_info.imageLayout = vk::ImageLayout::eShaderReadOnlyOptimal;
@@ -67,7 +67,7 @@ static bool BindBuffers(const Bindings& bindings,
                         const std::vector<DescriptorSetLayout>& desc_set,
                         std::vector<vk::DescriptorBufferInfo>& buffers,
                         std::vector<vk::WriteDescriptorSet>& writes) {
-  for (const auto& data : bindings.buffers) {
+  for (const BufferAndUniformSlot& data : bindings.buffers) {
     const auto& buffer_view = data.view.resource.buffer;
 
     auto device_buffer = buffer_view->GetDeviceBuffer(allocator);
diff --git a/impeller/renderer/backend/vulkan/compute_pass_vk.cc b/impeller/renderer/backend/vulkan/compute_pass_vk.cc
index 56bc71cd782a0..fffc615e5d04b 100644
--- a/impeller/renderer/backend/vulkan/compute_pass_vk.cc
+++ b/impeller/renderer/backend/vulkan/compute_pass_vk.cc
@@ -9,6 +9,7 @@
 #include "impeller/renderer/backend/vulkan/command_buffer_vk.h"
 #include "impeller/renderer/backend/vulkan/compute_pipeline_vk.h"
 #include "impeller/renderer/backend/vulkan/texture_vk.h"
+#include "impeller/renderer/command.h"
 
 namespace impeller {
 
@@ -43,7 +44,7 @@ static bool UpdateBindingLayouts(const Bindings& bindings,
 
   barrier.new_layout = vk::ImageLayout::eShaderReadOnlyOptimal;
 
-  for (const auto& data : bindings.sampled_images) {
+  for (const TextureAndSampler& data : bindings.sampled_images) {
     if (!TextureVK::Cast(*data.texture.resource).SetLayout(barrier)) {
       return false;
     }
@@ -58,7 +59,7 @@ static bool UpdateBindingLayouts(const ComputeCommand& command,
 
 static bool UpdateBindingLayouts(const std::vector<ComputeCommand>& commands,
                                  const vk::CommandBuffer& buffer) {
-  for (const auto& command : commands) {
+  for (const ComputeCommand& command : commands) {
     if (!UpdateBindingLayouts(command, buffer)) {
       return false;
     }
diff --git a/impeller/renderer/command.cc b/impeller/renderer/command.cc
index c40350d54a24b..40dfd8c09d518 100644
--- a/impeller/renderer/command.cc
+++ b/impeller/renderer/command.cc
@@ -66,7 +66,7 @@ bool Command::DoBindResource(ShaderStage stage,
 }
 
 bool Command::BindResource(ShaderStage stage,
-                           const ShaderUniformSlot& slot,
+                           const SampledImageSlot& slot,
                            const ShaderMetadata& metadata,
                            std::shared_ptr<const Texture> texture,
                            std::shared_ptr<const Sampler> sampler) {
diff --git a/impeller/renderer/command.h b/impeller/renderer/command.h
index 8f041d5086871..6351a4599df9f 100644
--- a/impeller/renderer/command.h
+++ b/impeller/renderer/command.h
@@ -59,7 +59,7 @@ using TextureResource = Resource<std::shared_ptr<const Texture>>;
 
 /// @brief combines the texture, sampler and sampler slot information.
 struct TextureAndSampler {
-  ShaderUniformSlot slot;
+  SampledImageSlot slot;
   TextureResource texture;
   std::shared_ptr<const Sampler> sampler;
 };
@@ -173,7 +173,7 @@ struct Command : public ResourceBinder {
 
   // |ResourceBinder|
   bool BindResource(ShaderStage stage,
-                    const ShaderUniformSlot& slot,
+                    const SampledImageSlot& slot,
                     const ShaderMetadata& metadata,
                     std::shared_ptr<const Texture> texture,
                     std::shared_ptr<const Sampler> sampler) override;
diff --git a/impeller/renderer/compute_command.cc b/impeller/renderer/compute_command.cc
index 62f2491b4f456..fbbfe3b58666f 100644
--- a/impeller/renderer/compute_command.cc
+++ b/impeller/renderer/compute_command.cc
@@ -29,7 +29,7 @@ bool ComputeCommand::BindResource(ShaderStage stage,
 }
 
 bool ComputeCommand::BindResource(ShaderStage stage,
-                                  const ShaderUniformSlot& slot,
+                                  const SampledImageSlot& slot,
                                   const ShaderMetadata& metadata,
                                   std::shared_ptr<const Texture> texture,
                                   std::shared_ptr<const Sampler> sampler) {
diff --git a/impeller/renderer/compute_command.h b/impeller/renderer/compute_command.h
index 511590ab31690..1a2d51503698c 100644
--- a/impeller/renderer/compute_command.h
+++ b/impeller/renderer/compute_command.h
@@ -58,7 +58,7 @@ struct ComputeCommand : public ResourceBinder {
 
   // |ResourceBinder|
   bool BindResource(ShaderStage stage,
-                    const ShaderUniformSlot& slot,
+                    const SampledImageSlot& slot,
                     const ShaderMetadata& metadata,
                     std::shared_ptr<const Texture> texture,
                     std::shared_ptr<const Sampler> sampler) override;
diff --git a/lib/gpu/render_pass.cc b/lib/gpu/render_pass.cc
index 4be78f80dc6d9..98ea3160cbcc5 100644
--- a/lib/gpu/render_pass.cc
+++ b/lib/gpu/render_pass.cc
@@ -384,8 +384,8 @@ bool InternalFlutterGpu_RenderPass_BindTexture(
   auto sampler = wrapper->GetContext().lock()->GetSamplerLibrary()->GetSampler(
       sampler_desc);
 
-  impeller::ShaderUniformSlot image_slot;
-  image_slot.ext_res_0 = slot_id;
+  impeller::SampledImageSlot image_slot;
+  image_slot.texture_index = slot_id;
   return command.BindResource(flutter::gpu::ToImpellerShaderStage(stage),
                               image_slot, metadata, texture->GetTexture(),
                               sampler);

From 1f7dfdc4675f4e5de40df9001c4f9a6b08207f79 Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 6 Dec 2023 09:59:33 -0800
Subject: [PATCH 3/5] missed one.

---
 impeller/renderer/backend/vulkan/render_pass_vk.cc | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/impeller/renderer/backend/vulkan/render_pass_vk.cc b/impeller/renderer/backend/vulkan/render_pass_vk.cc
index 9b624155f9b13..615ab1e27617f 100644
--- a/impeller/renderer/backend/vulkan/render_pass_vk.cc
+++ b/impeller/renderer/backend/vulkan/render_pass_vk.cc
@@ -21,6 +21,7 @@
 #include "impeller/renderer/backend/vulkan/pipeline_vk.h"
 #include "impeller/renderer/backend/vulkan/shared_object_vk.h"
 #include "impeller/renderer/backend/vulkan/texture_vk.h"
+#include "impeller/renderer/command.h"
 #include "vulkan/vulkan_enums.hpp"
 #include "vulkan/vulkan_handles.hpp"
 #include "vulkan/vulkan_to_string.hpp"
@@ -315,7 +316,7 @@ static bool UpdateBindingLayouts(const Bindings& bindings,
 
   barrier.new_layout = vk::ImageLayout::eShaderReadOnlyOptimal;
 
-  for (const auto& data : bindings.sampled_images) {
+  for (const TextureAndSampler& data : bindings.sampled_images) {
     if (!TextureVK::Cast(*data.texture.resource).SetLayout(barrier)) {
       return false;
     }
@@ -331,7 +332,7 @@ static bool UpdateBindingLayouts(const Command& command,
 
 static bool UpdateBindingLayouts(const std::vector<Command>& commands,
                                  const vk::CommandBuffer& buffer) {
-  for (const auto& command : commands) {
+  for (const Command& command : commands) {
     if (!UpdateBindingLayouts(command, buffer)) {
       return false;
     }

From 298c2b5964e6f897d72d53bb3c21cc80fd4f403b Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 6 Dec 2023 10:06:23 -0800
Subject: [PATCH 4/5] revert template changes.

---
 impeller/compiler/code_gen_template.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/impeller/compiler/code_gen_template.h b/impeller/compiler/code_gen_template.h
index 7927c71d2952c..1e73aee4a885a 100644
--- a/impeller/compiler/code_gen_template.h
+++ b/impeller/compiler/code_gen_template.h
@@ -120,9 +120,10 @@ struct {{camel_case(shader_name)}}{{camel_case(shader_stage)}}Shader {
 
   static constexpr auto kResource{{camel_case(sampled_image.name)}} = SampledImageSlot { // {{sampled_image.name}}
     "{{sampled_image.name}}",      // name
-    {{sampled_image.ext_res_0}}u,  // ext_res_0
-    {{sampled_image.set}}u,        // set
+    {{sampled_image.ext_res_0}}u,  // texture
+    {{sampled_image.ext_res_1}}u,  // sampler
     {{sampled_image.binding}}u,    // binding
+    {{sampled_image.set}}u,        // set
   };
   static ShaderMetadata kMetadata{{camel_case(sampled_image.name)}};
 {% endfor %}

From 4e5a81418bdaa3b4d63c0e8fb450e8f8b874db8b Mon Sep 17 00:00:00 2001
From: jonahwilliams <jonahwilliams@google.com>
Date: Wed, 6 Dec 2023 10:17:35 -0800
Subject: [PATCH 5/5] ++

---
 impeller/compiler/code_gen_template.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/impeller/compiler/code_gen_template.h b/impeller/compiler/code_gen_template.h
index 1e73aee4a885a..7927c71d2952c 100644
--- a/impeller/compiler/code_gen_template.h
+++ b/impeller/compiler/code_gen_template.h
@@ -120,10 +120,9 @@ struct {{camel_case(shader_name)}}{{camel_case(shader_stage)}}Shader {
 
   static constexpr auto kResource{{camel_case(sampled_image.name)}} = SampledImageSlot { // {{sampled_image.name}}
     "{{sampled_image.name}}",      // name
-    {{sampled_image.ext_res_0}}u,  // texture
-    {{sampled_image.ext_res_1}}u,  // sampler
-    {{sampled_image.binding}}u,    // binding
+    {{sampled_image.ext_res_0}}u,  // ext_res_0
     {{sampled_image.set}}u,        // set
+    {{sampled_image.binding}}u,    // binding
   };
   static ShaderMetadata kMetadata{{camel_case(sampled_image.name)}};
 {% endfor %}