| Flutter Impeller |

Public Types | Static Public Member Functions | Static Public Attributes | List of all members
impeller::PipelineBuilder< VertexShader_, FragmentShader_ > Struct Template Reference

An optional (but highly recommended) utility for creating pipelines from reflected shader information. More...

`#include <pipeline_builder.h>`

## Public Types
using | VertexShader = VertexShader_
using | FragmentShader = FragmentShader_

## Static Public Member Functions
static std::optional< PipelineDescriptor > | MakeDefaultPipelineDescriptor (const Context &context, const std::vector< Scalar > &constants={})
| Create a default pipeline descriptor using the combination reflected shader information. The descriptor can be configured further before a pipeline state object is created using it. More...
static bool | InitializePipelineDescriptorDefaults (const Context &context, PipelineDescriptor &desc)

## Static Public Attributes
static constexpr size_t | kVertexBufferIndex

## Detailed Description

### template<class VertexShader_, class FragmentShader_>
struct impeller::PipelineBuilder< VertexShader_, FragmentShader_ >

An optional (but highly recommended) utility for creating pipelines from reflected shader information.

Template Parameters

  VertexShader_ | The reflected vertex shader information. Found in a generated header file called <shader_name>.vert.h.
  FragmentShader_ | The reflected fragment shader information. Found in a generated header file called <shader_name>.frag.h.

Definition at line 31 of file pipeline_builder.h.

## Member Typedef Documentation

## ◆ FragmentShader

template<class VertexShader_ , class FragmentShader_ >

using impeller::PipelineBuilder< VertexShader_, FragmentShader_ >::FragmentShader = FragmentShader_

Definition at line 34 of file pipeline_builder.h.

## ◆ VertexShader

template<class VertexShader_ , class FragmentShader_ >

using impeller::PipelineBuilder< VertexShader_, FragmentShader_ >::VertexShader = VertexShader_

Definition at line 33 of file pipeline_builder.h.

## Member Function Documentation

## ◆ InitializePipelineDescriptorDefaults()

template<class VertexShader_ , class FragmentShader_ >

static bool impeller::PipelineBuilder< VertexShader_, FragmentShader_ >::InitializePipelineDescriptorDefaults | ( | const Context & | context,
|  | PipelineDescriptor & | desc
| ) |  |
| inline static

Definition at line 61 of file pipeline_builder.h.

63 {
64 // Setup debug instrumentation.
65 desc.SetLabel(std::format("{} Pipeline", FragmentShader::kLabel));
66
67 // Resolve pipeline entrypoints.
68 {
69 auto vertex_function = context.GetShaderLibrary()->GetFunction(
70 VertexShader::kEntrypointName, ShaderStage::kVertex);
71 auto fragment_function = context.GetShaderLibrary()->GetFunction(
72 FragmentShader::kEntrypointName, ShaderStage::kFragment);
73
74 if (!vertex_function || !fragment_function) {
75 VALIDATION_LOG << "Could not resolve pipeline entrypoint(s) '"
76 << VertexShader::kEntrypointName << "' and '"
77 << FragmentShader::kEntrypointName
78 << "' for pipeline named '" << VertexShader::kLabel
79 << "'.";
80 return false;
81 }
82
83 desc.AddStageEntrypoint(std::move(vertex_function));
84 desc.AddStageEntrypoint(std::move(fragment_function));
85 }
86
87 // Setup the vertex descriptor from reflected information.
88 {
89 auto vertex_descriptor = std::make_shared<VertexDescriptor>();
90 vertex_descriptor->SetStageInputs(VertexShader::kAllShaderStageInputs,
91 VertexShader::kInterleavedBufferLayout);
92 vertex_descriptor->RegisterDescriptorSetLayouts(
93 VertexShader::kDescriptorSetLayouts);
94 vertex_descriptor->RegisterDescriptorSetLayouts(
95 FragmentShader::kDescriptorSetLayouts);
96 desc.SetVertexDescriptor(std::move(vertex_descriptor));
97 }
98
99 // Setup fragment shader output descriptions.
100 {
101 // Configure the sole color attachments pixel format. This is by
102 // convention.
103 ColorAttachmentDescriptor color0;
104 color0.format = context.GetCapabilities()->GetDefaultColorFormat();
105 color0.blending_enabled = true;
106 desc.SetColorAttachmentDescriptor(0u, color0);
107 }
108
109 // Setup default depth buffer descriptions.
110 {
111 DepthAttachmentDescriptor depth0;
112 depth0.depth_compare = CompareFunction::kAlways;
113 desc.SetDepthStencilAttachmentDescriptor(depth0);
114 desc.SetDepthPixelFormat(
115 context.GetCapabilities()->GetDefaultDepthStencilFormat());
116 }
117
118 // Setup default stencil buffer descriptions.
119 {
120 StencilAttachmentDescriptor stencil0;
121 stencil0.stencil_compare = CompareFunction::kEqual;
122 desc.SetStencilAttachmentDescriptors(stencil0);
123 desc.SetStencilPixelFormat(
124 context.GetCapabilities()->GetDefaultDepthStencilFormat());
125 }
126
127 return true;
128 }
impeller::CompareFunction::kEqual
@ kEqual
Comparison test passes if new_value == current_value.
impeller::CompareFunction::kAlways
@ kAlways
Comparison test passes always passes.
impeller::ShaderStage::kFragment
@ kFragment
impeller::ShaderStage::kVertex
@ kVertex
VALIDATION_LOG
#define VALIDATION_LOG
Definition: validation.h:91

References impeller::PipelineDescriptor::AddStageEntrypoint(), impeller::ColorAttachmentDescriptor::blending_enabled, impeller::DepthAttachmentDescriptor::depth_compare, impeller::ColorAttachmentDescriptor::format, impeller::Context::GetCapabilities(), impeller::Context::GetShaderLibrary(), impeller::kAlways, impeller::kEqual, impeller::kFragment, impeller::kVertex, impeller::PipelineDescriptor::SetColorAttachmentDescriptor(), impeller::PipelineDescriptor::SetDepthPixelFormat(), impeller::PipelineDescriptor::SetDepthStencilAttachmentDescriptor(), impeller::PipelineDescriptor::SetLabel(), impeller::PipelineDescriptor::SetStencilAttachmentDescriptors(), impeller::PipelineDescriptor::SetStencilPixelFormat(), impeller::PipelineDescriptor::SetVertexDescriptor(), impeller::StencilAttachmentDescriptor::stencil_compare, and VALIDATION_LOG.

## ◆ MakeDefaultPipelineDescriptor()

template<class VertexShader_ , class FragmentShader_ >

static std::optional<PipelineDescriptor> impeller::PipelineBuilder< VertexShader_, FragmentShader_ >::MakeDefaultPipelineDescriptor | ( | const Context & | context,
|  | const std::vector< Scalar > & | constants = `{}`
| ) |  |
| inline static

Create a default pipeline descriptor using the combination reflected shader information. The descriptor can be configured further before a pipeline state object is created using it.

Parameters

  [in] | context | The context

Returns
  If the combination of reflected shader information is compatible and the requisite functions can be found in the context, a pipeline descriptor.

Definition at line 50 of file pipeline_builder.h.

52 {}) {
53 PipelineDescriptor desc;
54 desc.SetSpecializationConstants(constants);
55 if (InitializePipelineDescriptorDefaults(context, desc)) {
56 return {std::move(desc)};
57 }
58 return std::nullopt;
59 }
impeller::PipelineBuilder::InitializePipelineDescriptorDefaults
static bool InitializePipelineDescriptorDefaults(const Context &context, PipelineDescriptor &desc)
Definition: pipeline_builder.h:61

Referenced by impeller::ContentContext::ContentContext(), and impeller::testing::TEST_P().

## Member Data Documentation

## ◆ kVertexBufferIndex

template<class VertexShader_ , class FragmentShader_ >

constexpr size_t impeller::PipelineBuilder< VertexShader_, FragmentShader_ >::kVertexBufferIndex
| static constexpr

Initial value:
=
VertexDescriptor::kReservedVertexBufferIndex
impeller::VertexDescriptor::kReservedVertexBufferIndex
static constexpr size_t kReservedVertexBufferIndex
Definition: vertex_descriptor.h:25

Definition at line 36 of file pipeline_builder.h.

The documentation for this struct was generated from the following file:

- impeller/renderer/pipeline_builder.h