Flutter Impeller
code_gen_template.h
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include <string_view>
6 
7 namespace impeller {
8 namespace compiler {
9 
10 constexpr std::string_view kReflectionHeaderTemplate =
11  R"~~(// THIS FILE IS GENERATED BY impellerc.
12 // DO NOT EDIT OR CHECK THIS INTO SOURCE CONTROL
13 
14 #pragma once
15 
16 {# Note: The nogncheck decorations are only to make GN not mad at the template#}
17 {# this file is generated from. There are no GN rule violations in the generated#}
18 {# file itself and the no-check declarations will be stripped in generated files.#}
19 #include "impeller/core/buffer_view.h" {# // nogncheck #}
20 
21 #include "impeller/core/sampler.h" {# // nogncheck #}
22 
23 #include "impeller/core/shader_types.h" {# // nogncheck #}
24 
25 #include "impeller/core/resource_binder.h" {# // nogncheck #}
26 
27 #include "impeller/core/texture.h" {# // nogncheck #}
28 
29 
30 namespace impeller {
31 
32 struct {{camel_case(shader_name)}}{{camel_case(shader_stage)}}Shader {
33  // ===========================================================================
34  // Stage Info ================================================================
35  // ===========================================================================
36  static constexpr std::string_view kLabel = "{{camel_case(shader_name)}}";
37  static constexpr std::string_view kEntrypointName = "{{entrypoint}}";
38  static constexpr ShaderStage kShaderStage = {{to_shader_stage(shader_stage)}};
39  // The generator used to prepare these bindings. Metal generators may be used
40  // by GLES backends but GLES generators are unsuitable for the metal backend.
41  static constexpr std::string_view kGeneratorName = "{{get_generator_name()}}";
42 {% if length(struct_definitions) > 0 %}
43  // ===========================================================================
44  // Struct Definitions ========================================================
45  // ===========================================================================
46 {% for def in struct_definitions %}
47 
48 {% if last(def.members).array_elements == 0 %}
49  template <size_t FlexCount>
50 {% endif %}
51  struct {{def.name}} {
52 {% for member in def.members %}
53 {{" "}}{% if member.element_padding > 0 %}Padded<{{member.type}}, {{member.element_padding}}>{% else %}{{member.type}}{% endif %}{{" " + member.name}}{% if member.array_elements != "std::nullopt" %}[{% if member.array_elements == 0 %}FlexCount{% else %}{{member.array_elements}}{% endif %}]{% endif %}; // (offset {{member.offset}}, size {{member.byte_length}})
54 {% endfor %}
55  }; // struct {{def.name}} (size {{def.byte_length}})
56 {% endfor %}
57 {% endif %}
58 {% if length(buffers) > 0 %}
59 
60  // ===========================================================================
61  // Stage Uniform & Storage Buffers ===========================================
62  // ===========================================================================
63 {% for buffer in buffers %}
64 
65  static constexpr auto kResource{{camel_case(buffer.name)}} = ShaderUniformSlot { // {{buffer.name}}
66  "{{buffer.name}}", // name
67  {{buffer.ext_res_0}}u, // ext_res_0
68  {{buffer.set}}u, // set
69  {{buffer.binding}}u, // binding
70  };
71  static ShaderMetadata kMetadata{{camel_case(buffer.name)}};
72 {% endfor %}
73 {% endif %}
74 
75  // ===========================================================================
76  // Stage Inputs ==============================================================
77  // ===========================================================================
78 {% for stage_input in stage_inputs %}
79  static constexpr auto kInput{{camel_case(stage_input.name)}} = ShaderStageIOSlot { // {{stage_input.name}}
80  "{{stage_input.name}}", // name
81  {{stage_input.location}}u, // attribute location
82  {{stage_input.descriptor_set}}u, // attribute set
83  {{stage_input.binding}}u, // attribute binding
84  {{stage_input.type.type_name}}, // type
85  {{stage_input.type.bit_width}}u, // bit width of type
86  {{stage_input.type.vec_size}}u, // vec size
87  {{stage_input.type.columns}}u, // number of columns
88  {{stage_input.offset}}u, // offset for interleaved layout
89  {{stage_input.relaxed_precision}}, // relaxed precision
90  };
91 {% endfor %}
92 
93  static constexpr std::array<const ShaderStageIOSlot*, {{length(stage_inputs)}}> kAllShaderStageInputs = {
94 {% for stage_input in stage_inputs %}
95  &kInput{{camel_case(stage_input.name)}}, // {{stage_input.name}}
96 {% endfor %}
97  };
98 
99 {% if shader_stage == "vertex" %}
100  static constexpr auto kInterleavedLayout = ShaderStageBufferLayout {
101 {% if length(stage_inputs) > 0 %}
102  sizeof(PerVertexData), // stride for interleaved layout
103 {% else %}
104  0u,
105 {% endif %}
106  0u, // attribute binding
107  };
108  static constexpr std::array<const ShaderStageBufferLayout*, 1> kInterleavedBufferLayout = {
109  &kInterleavedLayout
110  };
111 {% endif %}
112 
113 {% if length(sampled_images) > 0 %}
114  // ===========================================================================
115  // Sampled Images ============================================================
116  // ===========================================================================
117 {% for sampled_image in sampled_images %}
118 
119  static constexpr auto kResource{{camel_case(sampled_image.name)}} = SampledImageSlot { // {{sampled_image.name}}
120  "{{sampled_image.name}}", // name
121  {{sampled_image.ext_res_0}}u, // ext_res_0
122  {{sampled_image.set}}u, // set
123  {{sampled_image.binding}}u, // binding
124  };
125  static ShaderMetadata kMetadata{{camel_case(sampled_image.name)}};
126 {% endfor %}
127 {% endif %}
128  // ===========================================================================
129  // Stage Outputs =============================================================
130  // ===========================================================================
131 {% for stage_output in stage_outputs %}
132  static constexpr auto kOutput{{camel_case(stage_output.name)}} = ShaderStageIOSlot { // {{stage_output.name}}
133  "{{stage_output.name}}", // name
134  {{stage_output.location}}u, // attribute location
135  {{stage_output.descriptor_set}}u, // attribute set
136  {{stage_output.binding}}u, // attribute binding
137  {{stage_output.type.type_name}}, // type
138  {{stage_output.type.bit_width}}u, // bit width of type
139  {{stage_output.type.vec_size}}u, // vec size
140  {{stage_output.type.columns}}u, // number of columns
141  {{stage_output.offset}}u, // offset for interleaved layout
142  {{stage_output.relaxed_precision}}, // relaxed precision
143  };
144 {% endfor %}
145  static constexpr std::array<const ShaderStageIOSlot*, {{length(stage_outputs)}}> kAllShaderStageOutputs = {
146 {% for stage_output in stage_outputs %}
147  &kOutput{{camel_case(stage_output.name)}}, // {{stage_output.name}}
148 {% endfor %}
149  };
150 
151  // ===========================================================================
152  // Resource Binding Utilities ================================================
153  // ===========================================================================
154 
155 {% for proto in bind_prototypes %}
156  /// {{proto.docstring}}
157  static {{proto.return_type}} Bind{{proto.name}}({% for arg in proto.args %}
158 {{arg.type_name}} {{arg.argument_name}}{% if not loop.is_last %}, {% endif %}
159 {% endfor %}) {
160  return {{ proto.args.0.argument_name }}.BindResource({% for arg in proto.args %}
161  {% if loop.is_first %}
162 {{to_shader_stage(shader_stage)}}, {{ proto.descriptor_type }}, kResource{{ proto.name }}, &kMetadata{{ proto.name }}, {% else %}
163 std::move({{ arg.argument_name }}){% if not loop.is_last %}, {% endif %}
164  {% endif %}
165  {% endfor %});
166  }
167 
168 {% endfor %}
169 
170  // ===========================================================================
171  // Metadata for Vulkan =======================================================
172  // ===========================================================================
173  static constexpr std::array<DescriptorSetLayout,{{length(buffers)+length(sampled_images)+length(subpass_inputs)}}> kDescriptorSetLayouts{
174 {% for subpass_input in subpass_inputs %}
175  DescriptorSetLayout{
176  {{subpass_input.binding}}, // binding = {{subpass_input.binding}}
177  {{subpass_input.descriptor_type}}, // descriptor_type = {{subpass_input.descriptor_type}}
178  {{to_shader_stage(shader_stage)}}, // shader_stage = {{to_shader_stage(shader_stage)}}
179  },
180 {% endfor %}
181 {% for buffer in buffers %}
182  DescriptorSetLayout{
183  {{buffer.binding}}, // binding = {{buffer.binding}}
184  {{buffer.descriptor_type}}, // descriptor_type = {{buffer.descriptor_type}}
185  {{to_shader_stage(shader_stage)}}, // shader_stage = {{to_shader_stage(shader_stage)}}
186  },
187 {% endfor %}
188 {% for sampled_image in sampled_images %}
189  DescriptorSetLayout{
190  {{sampled_image.binding}}, // binding = {{sampled_image.binding}}
191  {{sampled_image.descriptor_type}}, // descriptor_type = {{sampled_image.descriptor_type}}
192  {{to_shader_stage(shader_stage)}}, // shader_stage = {{to_shader_stage(shader_stage)}}
193  },
194 {% endfor %}
195  };
196 
197 }; // struct {{camel_case(shader_name)}}{{camel_case(shader_stage)}}Shader
198 
199 } // namespace impeller
200 )~~";
201 
202 constexpr std::string_view kReflectionCCTemplate =
203  R"~~(// THIS FILE IS GENERATED BY impellerc.
204 // DO NOT EDIT OR CHECK THIS INTO SOURCE CONTROL
205 
206 #include "{{header_file_name}}"
207 
208 #include <type_traits>
209 
210 namespace impeller {
211 
212 using Shader = {{camel_case(shader_name)}}{{camel_case(shader_stage)}}Shader;
213 
214 {% for def in struct_definitions %}
215 // Sanity checks for {{def.name}}
216 {% if last(def.members).array_elements == 0 %}
217 static_assert(std::is_standard_layout_v<Shader::{{def.name}}<0>>);
218 {% for member in def.members %}
219 static_assert(offsetof(Shader::{{def.name}}<0>, {{member.name}}) == {{member.offset}});
220 {% endfor %}
221 {% else %}
222 static_assert(std::is_standard_layout_v<Shader::{{def.name}}>);
223 static_assert(sizeof(Shader::{{def.name}}) == {{def.byte_length}});
224 {% for member in def.members %}
225 static_assert(offsetof(Shader::{{def.name}}, {{member.name}}) == {{member.offset}});
226 {% endfor %}
227 {% endif %}
228 {% endfor %}
229 
230 {% for buffer in buffers %}
231 ShaderMetadata Shader::kMetadata{{camel_case(buffer.name)}} = {
232  "{{buffer.name}}", // name
233  std::vector<ShaderStructMemberMetadata> {
234  {% for member in buffer.type.members %}
235  ShaderStructMemberMetadata {
236  {{ member.base_type }}, // type
237  "{{ member.name }}", // name
238  {{ member.offset }}, // offset
239  {{ member.size }}, // size
240  {{ member.byte_length }}, // byte_length
241  {{ member.array_elements }}, // array_elements
242  },
243  {% endfor %}
244  } // members
245 };
246 {% endfor %}
247 
248 {% for sampled_image in sampled_images %}
249 ShaderMetadata Shader::kMetadata{{camel_case(sampled_image.name)}} = {
250  "{{sampled_image.name}}", // name
251  std::vector<ShaderStructMemberMetadata> {}, // 0 members
252 };
253 {% endfor %}
254 
255 } // namespace impeller
256 )~~";
257 
258 } // namespace compiler
259 } // namespace impeller
constexpr std::string_view kReflectionHeaderTemplate
constexpr std::string_view kReflectionCCTemplate