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capabilities.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 #ifndef FLUTTER_IMPELLER_RENDERER_CAPABILITIES_H_
6 #define FLUTTER_IMPELLER_RENDERER_CAPABILITIES_H_
7
8 #include <memory>
9
10 #include "impeller/core/formats.h"
11
12 namespace impeller {
13
14 class Capabilities {
15 public:
16 virtual ~Capabilities();
17
18 /// @brief Whether the context backend supports attaching offscreen MSAA
19 /// color/stencil textures.
20 virtual bool SupportsOffscreenMSAA() const = 0;
21
22 /// @brief Whether the context backend supports multisampled rendering to
23 /// the on-screen surface without requiring an explicit resolve of
24 /// the MSAA color attachment.
25 virtual bool SupportsImplicitResolvingMSAA() const = 0;
26
27 /// @brief Whether the context backend supports binding Shader Storage Buffer
28 /// Objects (SSBOs) to pipelines.
29 virtual bool SupportsSSBO() const = 0;
30
31 /// @brief Whether the context backend supports blitting from one texture
32 /// region to another texture region (via the relevant
33 /// `BlitPass::AddCopy` overloads).
34 virtual bool SupportsTextureToTextureBlits() const = 0;
35
36 /// @brief Whether the context backend is able to support pipelines with
37 /// shaders that read from the framebuffer (i.e. pixels that have been
38 /// written by previous draw calls in the current render pass).
39 ///
40 /// Example of reading from the first color attachment in a GLSL
41 /// shader:
42 /// ```
43 /// uniform subpassInput subpass_input;
44 ///
45 /// out vec4 frag_color;
46 ///
47 /// void main() {
48 /// vec4 color = subpassLoad(subpass_input);
49 /// // Invert the colors drawn to the framebuffer.
50 /// frag_color = vec4(vec3(1) - color.rgb, color.a);
51 /// }
52 /// ```
53 virtual bool SupportsFramebufferFetch() const = 0;
54
55 /// @brief Whether the context backend supports `ComputePass`.
56 virtual bool SupportsCompute() const = 0;
57
58 /// @brief Whether the context backend supports configuring `ComputePass`
59 /// command subgroups.
60 virtual bool SupportsComputeSubgroups() const = 0;
61
62 /// @brief Whether the context backend supports binding the current
63 /// `RenderPass` attachments. This is supported if the backend can
64 /// guarantee that attachment textures will not be mutated until the
65 /// render pass has fully completed.
66 ///
67 /// This is possible because many mobile graphics cards track
68 /// `RenderPass` attachment state in intermediary tile memory prior to
69 /// Storing the pass in the heap allocated attachments on DRAM.
70 /// Metal's hazard tracking and Vulkan's barriers are granular enough
71 /// to allow for safely accessing attachment textures prior to storage
72 /// in the same `RenderPass`.
73 virtual bool SupportsReadFromResolve() const = 0;
74
75 /// @brief Whether the context backend supports `SamplerAddressMode::Decal`.
76 virtual bool SupportsDecalSamplerAddressMode() const = 0;
77
78 /// @brief Whether the context backend supports allocating
79 /// `StorageMode::kDeviceTransient` (aka "memoryless") textures, which
80 /// are temporary textures kept in tile memory for the duration of the
81 /// `RenderPass` it's attached to.
82 ///
83 /// This feature is especially useful for MSAA and stencils.
84 virtual bool SupportsDeviceTransientTextures() const = 0;
85
86 /// @brief Whether the primitive type TriangleFan is supported by the backend.
87 virtual bool SupportsTriangleFan() const = 0;
88
89 /// @brief Whether primitive restart is supported.
90 virtual bool SupportsPrimitiveRestart() const = 0;
91
92 /// @brief Returns a supported `PixelFormat` for textures that store
93 /// 4-channel colors (red/green/blue/alpha).
94 virtual PixelFormat GetDefaultColorFormat() const = 0;
95
96 /// @brief Returns a supported `PixelFormat` for textures that store stencil
97 /// information. May include a depth channel if a stencil-only format
98 /// is not available.
99 virtual PixelFormat GetDefaultStencilFormat() const = 0;
100
101 /// @brief Returns a supported `PixelFormat` for textures that store both a
102 /// stencil and depth component. This will never return a depth-only
103 /// or stencil-only texture.
104 /// Returns `PixelFormat::kUnknown` if no suitable depth+stencil
105 /// format was found.
106 virtual PixelFormat GetDefaultDepthStencilFormat() const = 0;
107
108 /// @brief Returns the default pixel format for the alpha bitmap glyph atlas.
109 ///
110 /// Some backends may use Red channel while others use grey. This
111 /// should not have any impact
112 virtual PixelFormat GetDefaultGlyphAtlasFormat() const = 0;
113
114 /// @brief Return the maximum size of a render pass attachment.
115 ///
116 /// Note that this may be smaller than the maximum allocatable texture size.
117 virtual ISize GetMaximumRenderPassAttachmentSize() const = 0;
118
119 /// @brief Whether the XR formats are supported on this device.
120 ///
121 /// This is only ever true for iOS and macOS devices. We may need
122 /// to revisit this API when approaching wide gamut rendering for
123 /// Vulkan and GLES.
124 virtual bool SupportsExtendedRangeFormats() const = 0;
125
126 /// @brief The minimum alignment of uniform value offsets in bytes.
127 virtual size_t GetMinimumUniformAlignment() const = 0;
128
129 protected:
130 Capabilities();
131
132 Capabilities(const Capabilities&) = delete;
133
134 Capabilities& operator=(const Capabilities&) = delete;
135 };
136
137 class CapabilitiesBuilder {
138 public:
139 CapabilitiesBuilder();
140
141 ~CapabilitiesBuilder();
142
143 CapabilitiesBuilder& SetSupportsOffscreenMSAA(bool value);
144
145 CapabilitiesBuilder& SetSupportsSSBO(bool value);
146
147 CapabilitiesBuilder& SetSupportsTextureToTextureBlits(bool value);
148
149 CapabilitiesBuilder& SetSupportsFramebufferFetch(bool value);
150
151 CapabilitiesBuilder& SetSupportsCompute(bool value);
152
153 CapabilitiesBuilder& SetSupportsComputeSubgroups(bool value);
154
155 CapabilitiesBuilder& SetSupportsReadFromResolve(bool value);
156
157 CapabilitiesBuilder& SetDefaultColorFormat(PixelFormat value);
158
159 CapabilitiesBuilder& SetDefaultStencilFormat(PixelFormat value);
160
161 CapabilitiesBuilder& SetDefaultDepthStencilFormat(PixelFormat value);
162
163 CapabilitiesBuilder& SetSupportsDecalSamplerAddressMode(bool value);
164
165 CapabilitiesBuilder& SetSupportsDeviceTransientTextures(bool value);
166
167 CapabilitiesBuilder& SetSupportsExtendedRangeFormats(bool value);
168
169 CapabilitiesBuilder& SetDefaultGlyphAtlasFormat(PixelFormat value);
170
171 CapabilitiesBuilder& SetSupportsTriangleFan(bool value);
172
173 CapabilitiesBuilder& SetMaximumRenderPassAttachmentSize(ISize size);
174
175 CapabilitiesBuilder& SetMinimumUniformAlignment(size_t value);
176
177 std::unique_ptr<Capabilities> Build();
178
179 private:
180 bool supports_offscreen_msaa_ = false;
181 bool supports_ssbo_ = false;
182 bool supports_texture_to_texture_blits_ = false;
183 bool supports_framebuffer_fetch_ = false;
184 bool supports_compute_ = false;
185 bool supports_compute_subgroups_ = false;
186 bool supports_read_from_resolve_ = false;
187 bool supports_decal_sampler_address_mode_ = false;
188 bool supports_device_transient_textures_ = false;
189 bool supports_triangle_fan_ = false;
190 bool supports_extended_range_formats_ = false;
191 std::optional<PixelFormat> default_color_format_ = std::nullopt;
192 std::optional<PixelFormat> default_stencil_format_ = std::nullopt;
193 std::optional<PixelFormat> default_depth_stencil_format_ = std::nullopt;
194 std::optional<PixelFormat> default_glyph_atlas_format_ = std::nullopt;
195 std::optional<ISize> default_maximum_render_pass_attachment_size_ =
196 std::nullopt;
197 size_t minimum_uniform_alignment_ = 256;
198
199 CapabilitiesBuilder(const CapabilitiesBuilder&) = delete;
200
201 CapabilitiesBuilder& operator=(const CapabilitiesBuilder&) = delete;
202 };
203
204 } // namespace impeller
205
206 #endif // FLUTTER_IMPELLER_RENDERER_CAPABILITIES_H_
impeller::CapabilitiesBuilder
Definition: capabilities.h:137
impeller::CapabilitiesBuilder::SetDefaultColorFormat
CapabilitiesBuilder & SetDefaultColorFormat(PixelFormat value)
Definition: capabilities.cc:204
impeller::CapabilitiesBuilder::SetSupportsComputeSubgroups
CapabilitiesBuilder & SetSupportsComputeSubgroups(bool value)
Definition: capabilities.cc:198
impeller::CapabilitiesBuilder::SetMinimumUniformAlignment
CapabilitiesBuilder & SetMinimumUniformAlignment(size_t value)
Definition: capabilities.cc:263
impeller::CapabilitiesBuilder::SetSupportsTextureToTextureBlits
CapabilitiesBuilder & SetSupportsTextureToTextureBlits(bool value)
Definition: capabilities.cc:181
impeller::CapabilitiesBuilder::SetDefaultStencilFormat
CapabilitiesBuilder & SetDefaultStencilFormat(PixelFormat value)
Definition: capabilities.cc:210
impeller::CapabilitiesBuilder::CapabilitiesBuilder
CapabilitiesBuilder()
impeller::CapabilitiesBuilder::SetSupportsDeviceTransientTextures
CapabilitiesBuilder & SetSupportsDeviceTransientTextures(bool value)
Definition: capabilities.cc:234
impeller::CapabilitiesBuilder::SetSupportsTriangleFan
CapabilitiesBuilder & SetSupportsTriangleFan(bool value)
Definition: capabilities.cc:246
impeller::CapabilitiesBuilder::~CapabilitiesBuilder
~CapabilitiesBuilder()
impeller::CapabilitiesBuilder::SetSupportsFramebufferFetch
CapabilitiesBuilder & SetSupportsFramebufferFetch(bool value)
Definition: capabilities.cc:187
impeller::CapabilitiesBuilder::SetSupportsDecalSamplerAddressMode
CapabilitiesBuilder & SetSupportsDecalSamplerAddressMode(bool value)
Definition: capabilities.cc:228
impeller::CapabilitiesBuilder::SetSupportsOffscreenMSAA
CapabilitiesBuilder & SetSupportsOffscreenMSAA(bool value)
Definition: capabilities.cc:171
impeller::CapabilitiesBuilder::SetSupportsSSBO
CapabilitiesBuilder & SetSupportsSSBO(bool value)
Definition: capabilities.cc:176
impeller::CapabilitiesBuilder::SetMaximumRenderPassAttachmentSize
CapabilitiesBuilder & SetMaximumRenderPassAttachmentSize(ISize size)
Definition: capabilities.cc:251
impeller::CapabilitiesBuilder::SetSupportsExtendedRangeFormats
CapabilitiesBuilder & SetSupportsExtendedRangeFormats(bool value)
Definition: capabilities.cc:257
impeller::CapabilitiesBuilder::SetDefaultGlyphAtlasFormat
CapabilitiesBuilder & SetDefaultGlyphAtlasFormat(PixelFormat value)
Definition: capabilities.cc:240
impeller::CapabilitiesBuilder::SetSupportsCompute
CapabilitiesBuilder & SetSupportsCompute(bool value)
Definition: capabilities.cc:193
impeller::CapabilitiesBuilder::Build
std::unique_ptr< Capabilities > Build()
Definition: capabilities.cc:269
impeller::CapabilitiesBuilder::SetDefaultDepthStencilFormat
CapabilitiesBuilder & SetDefaultDepthStencilFormat(PixelFormat value)
Definition: capabilities.cc:216
impeller::CapabilitiesBuilder::SetSupportsReadFromResolve
CapabilitiesBuilder & SetSupportsReadFromResolve(bool value)
Definition: capabilities.cc:222
impeller::Capabilities
Definition: capabilities.h:14
impeller::Capabilities::GetDefaultStencilFormat
virtual PixelFormat GetDefaultStencilFormat() const =0
Returns a supported PixelFormat for textures that store stencil information. May include a depth chan...
impeller::Capabilities::GetMinimumUniformAlignment
virtual size_t GetMinimumUniformAlignment() const =0
The minimum alignment of uniform value offsets in bytes.
impeller::Capabilities::Capabilities
Capabilities()
impeller::Capabilities::SupportsOffscreenMSAA
virtual bool SupportsOffscreenMSAA() const =0
Whether the context backend supports attaching offscreen MSAA color/stencil textures.
impeller::Capabilities::SupportsImplicitResolvingMSAA
virtual bool SupportsImplicitResolvingMSAA() const =0
Whether the context backend supports multisampled rendering to the on-screen surface without requirin...
impeller::Capabilities::SupportsFramebufferFetch
virtual bool SupportsFramebufferFetch() const =0
Whether the context backend is able to support pipelines with shaders that read from the framebuffer ...
impeller::Capabilities::SupportsDecalSamplerAddressMode
virtual bool SupportsDecalSamplerAddressMode() const =0
Whether the context backend supports SamplerAddressMode::Decal.
impeller::Capabilities::SupportsReadFromResolve
virtual bool SupportsReadFromResolve() const =0
Whether the context backend supports binding the current RenderPass attachments. This is supported if...
impeller::Capabilities::SupportsTriangleFan
virtual bool SupportsTriangleFan() const =0
Whether the primitive type TriangleFan is supported by the backend.
impeller::Capabilities::SupportsComputeSubgroups
virtual bool SupportsComputeSubgroups() const =0
Whether the context backend supports configuring ComputePass command subgroups.
impeller::Capabilities::Capabilities
Capabilities(const Capabilities &)=delete
impeller::Capabilities::GetDefaultGlyphAtlasFormat
virtual PixelFormat GetDefaultGlyphAtlasFormat() const =0
Returns the default pixel format for the alpha bitmap glyph atlas.
impeller::Capabilities::SupportsPrimitiveRestart
virtual bool SupportsPrimitiveRestart() const =0
Whether primitive restart is supported.
impeller::Capabilities::GetDefaultColorFormat
virtual PixelFormat GetDefaultColorFormat() const =0
Returns a supported PixelFormat for textures that store 4-channel colors (red/green/blue/alpha).
impeller::Capabilities::~Capabilities
virtual ~Capabilities()
impeller::Capabilities::GetMaximumRenderPassAttachmentSize
virtual ISize GetMaximumRenderPassAttachmentSize() const =0
Return the maximum size of a render pass attachment.
impeller::Capabilities::SupportsDeviceTransientTextures
virtual bool SupportsDeviceTransientTextures() const =0
Whether the context backend supports allocating StorageMode::kDeviceTransient (aka "memoryless") text...
impeller::Capabilities::operator=
Capabilities & operator=(const Capabilities &)=delete
impeller::Capabilities::SupportsCompute
virtual bool SupportsCompute() const =0
Whether the context backend supports ComputePass.
impeller::Capabilities::SupportsExtendedRangeFormats
virtual bool SupportsExtendedRangeFormats() const =0
Whether the XR formats are supported on this device.
impeller::Capabilities::SupportsSSBO
virtual bool SupportsSSBO() const =0
Whether the context backend supports binding Shader Storage Buffer Objects (SSBOs) to pipelines.
impeller::Capabilities::GetDefaultDepthStencilFormat
virtual PixelFormat GetDefaultDepthStencilFormat() const =0
Returns a supported PixelFormat for textures that store both a stencil and depth component....
impeller::Capabilities::SupportsTextureToTextureBlits
virtual bool SupportsTextureToTextureBlits() const =0
Whether the context backend supports blitting from one texture region to another texture region (via ...
formats.h
value
int32_t value
Definition: dl_golden_unittests.cc:459
impeller
Definition: allocation.cc:12
impeller::PixelFormat
PixelFormat
The Pixel formats supported by Impeller. The naming convention denotes the usage of the component,...
Definition: formats.h:99
impeller::TSize
Definition: size.h:25