The Vulkan layers and extensions wrangler. More...

#include <capabilities_gles.h>

Inheritance diagram for impeller::CapabilitiesGLES:

Public Member Functions
	CapabilitiesGLES (const ProcTableGLES &gl)

	CapabilitiesGLES (const CapabilitiesGLES &)=delete

	CapabilitiesGLES (CapabilitiesGLES &&)=delete

CapabilitiesGLES &	operator= (const CapabilitiesGLES &)=delete

CapabilitiesGLES &	operator= (CapabilitiesGLES &&)=delete

size_t	GetMaxTextureUnits (ShaderStage stage) const

bool	IsANGLE () const

bool	IsES () const
	Whether this is an ES GL variant or (if false) desktop GL. More...

bool	SupportsOffscreenMSAA () const override
	Whether the context backend supports attaching offscreen MSAA color/stencil textures. More...

bool	SupportsImplicitResolvingMSAA () const override
	Whether the context backend supports multisampled rendering to the on-screen surface without requiring an explicit resolve of the MSAA color attachment. More...

bool	SupportsSSBO () const override
	Whether the context backend supports binding Shader Storage Buffer Objects (SSBOs) to pipelines. More...

bool	SupportsTextureToTextureBlits () const override
	Whether the context backend supports blitting from one texture region to another texture region (via the relevant `BlitPass::AddCopy` overloads). More...

bool	SupportsFramebufferFetch () const override
	Whether the context backend is able to support pipelines with shaders that read from the framebuffer (i.e. pixels that have been written by previous draw calls in the current render pass). More...

bool	SupportsCompute () const override
	Whether the context backend supports `ComputePass`. More...

bool	SupportsComputeSubgroups () const override
	Whether the context backend supports configuring `ComputePass` command subgroups. More...

bool	SupportsReadFromResolve () const override
	Whether the context backend supports binding the current `RenderPass` attachments. This is supported if the backend can guarantee that attachment textures will not be mutated until the render pass has fully completed. More...

bool	SupportsDecalSamplerAddressMode () const override
	Whether the context backend supports `SamplerAddressMode::Decal`. More...

bool	SupportsDeviceTransientTextures () const override
	Whether the context backend supports allocating `StorageMode::kDeviceTransient` (aka "memoryless") textures, which are temporary textures kept in tile memory for the duration of the `RenderPass` it's attached to. More...

bool	SupportsTriangleFan () const override
	Whether the primitive type TriangleFan is supported by the backend. More...

bool	SupportsPrimitiveRestart () const override
	Whether primitive restart is supported. More...

bool	SupportsExtendedRangeFormats () const override
	Whether the XR formats are supported on this device. More...

PixelFormat	GetDefaultColorFormat () const override
	Returns a supported `PixelFormat` for textures that store 4-channel colors (red/green/blue/alpha). More...

PixelFormat	GetDefaultStencilFormat () const override
	Returns a supported `PixelFormat` for textures that store stencil information. May include a depth channel if a stencil-only format is not available. More...

PixelFormat	GetDefaultDepthStencilFormat () const override
	Returns a supported `PixelFormat` for textures that store both a stencil and depth component. This will never return a depth-only or stencil-only texture. Returns `PixelFormat::kUnknown` if no suitable depth+stencil format was found. More...

PixelFormat	GetDefaultGlyphAtlasFormat () const override
	Returns the default pixel format for the alpha bitmap glyph atlas. More...

ISize	GetMaximumRenderPassAttachmentSize () const override
	Return the maximum size of a render pass attachment. More...

size_t	GetMinimumUniformAlignment () const override
	The minimum alignment of uniform value offsets in bytes. More...

Public Member Functions inherited from impeller::Capabilities
virtual	~Capabilities ()

Public Attributes
size_t	max_combined_texture_image_units = 8

size_t	max_cube_map_texture_size = 16

size_t	max_fragment_uniform_vectors = 16

size_t	max_renderbuffer_size = 1

size_t	max_texture_image_units = 8

ISize	max_texture_size = ISize{64, 64}

size_t	max_varying_vectors = 8

size_t	max_vertex_attribs = 8

size_t	max_vertex_texture_image_units = 0

size_t	max_vertex_uniform_vectors = 128

ISize	max_viewport_dims

size_t	num_compressed_texture_formats = 0

size_t	num_shader_binary_formats = 0

Additional Inherited Members
Static Public Member Functions inherited from impeller::BackendCast< CapabilitiesGLES, Capabilities >
static CapabilitiesGLES &	Cast (Capabilities &base)

static const CapabilitiesGLES &	Cast (const Capabilities &base)

static CapabilitiesGLES *	Cast (Capabilities *base)

static const CapabilitiesGLES *	Cast (const Capabilities *base)

Protected Member Functions inherited from impeller::Capabilities
	Capabilities ()

	Capabilities (const Capabilities &)=delete

Capabilities &	operator= (const Capabilities &)=delete

Detailed Description

The Vulkan layers and extensions wrangler.

Definition at line 23 of file capabilities_gles.h.

Constructor & Destructor Documentation

◆ CapabilitiesGLES() [1/3]

impeller::CapabilitiesGLES::CapabilitiesGLES ( const ProcTableGLES & gl )

explicit

Definition at line 29 of file capabilities_gles.cc.

                                                           {
   {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &value);
     max_combined_texture_image_units = value;
   }
  
   {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_CUBE_MAP_TEXTURE_SIZE, &value);
     max_cube_map_texture_size = value;
   }
  
   auto const desc = gl.GetDescription();
  
   if (desc->IsES()) {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_FRAGMENT_UNIFORM_VECTORS, &value);
     max_fragment_uniform_vectors = value;
   }
  
   {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_RENDERBUFFER_SIZE, &value);
     max_renderbuffer_size = value;
   }
  
   {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &value);
     max_texture_image_units = value;
   }
  
   {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_TEXTURE_SIZE, &value);
     max_texture_size = ISize{value, value};
   }
  
   if (desc->IsES()) {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_VARYING_VECTORS, &value);
     max_varying_vectors = value;
   }
  
   {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_VERTEX_ATTRIBS, &value);
     max_vertex_attribs = value;
   }
  
   {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS, &value);
     max_vertex_texture_image_units = value;
   }
  
   if (desc->IsES()) {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_VERTEX_UNIFORM_VECTORS, &value);
     max_vertex_uniform_vectors = value;
   }
  
   {
     GLint values[2] = {};
     gl.GetIntegerv(GL_MAX_VIEWPORT_DIMS, values);
     max_viewport_dims = ISize{values[0], values[1]};
   }
  
   {
     GLint value = 0;
     gl.GetIntegerv(GL_NUM_COMPRESSED_TEXTURE_FORMATS, &value);
     num_compressed_texture_formats = value;
   }
  
   if (desc->IsES()) {
     GLint value = 0;
     gl.GetIntegerv(GL_NUM_SHADER_BINARY_FORMATS, &value);
     num_shader_binary_formats = value;
   }
  
   if (desc->IsES()) {
     default_glyph_atlas_format_ = PixelFormat::kA8UNormInt;
   } else {
     default_glyph_atlas_format_ = PixelFormat::kR8UNormInt;
   }
  
   if (desc->GetGlVersion().major_version >= 3) {
     supports_texture_to_texture_blits_ = true;
   }
  
   supports_framebuffer_fetch_ = desc->HasExtension(kFramebufferFetchExt);
  
   if (desc->HasExtension(kTextureBorderClampExt) ||
       desc->HasExtension(kNvidiaTextureBorderClampExt)) {
     supports_decal_sampler_address_mode_ = true;
   }
  
   if (desc->HasExtension(kMultisampledRenderToTextureExt)) {
     supports_implicit_msaa_ = true;
  
     if (desc->HasExtension(kMultisampledRenderToTexture2Ext)) {
       // We hard-code 4x MSAA, so let's make sure it's supported.
       GLint value = 0;
       gl.GetIntegerv(GL_MAX_SAMPLES_EXT, &value);
       supports_offscreen_msaa_ = value >= 4;
     }
   } else if (desc->GetGlVersion().major_version >= 3 && desc->IsES()) {
     GLint value = 0;
     gl.GetIntegerv(GL_MAX_SAMPLES, &value);
     supports_offscreen_msaa_ = value >= 4;
   }
   is_es_ = desc->IsES();
   is_angle_ = desc->IsANGLE();
 }

References impeller::ProcTableGLES::GetDescription(), impeller::kA8UNormInt, impeller::kFramebufferFetchExt, impeller::kMultisampledRenderToTexture2Ext, impeller::kMultisampledRenderToTextureExt, impeller::kNvidiaTextureBorderClampExt, impeller::kR8UNormInt, impeller::kTextureBorderClampExt, max_combined_texture_image_units, max_cube_map_texture_size, max_fragment_uniform_vectors, max_renderbuffer_size, max_texture_image_units, max_texture_size, max_varying_vectors, max_vertex_attribs, max_vertex_texture_image_units, max_vertex_uniform_vectors, max_viewport_dims, num_compressed_texture_formats, num_shader_binary_formats, and value.

◆ CapabilitiesGLES() [2/3]

impeller::CapabilitiesGLES::CapabilitiesGLES ( const CapabilitiesGLES & )

delete

◆ CapabilitiesGLES() [3/3]

impeller::CapabilitiesGLES::CapabilitiesGLES ( CapabilitiesGLES && )

delete

Member Function Documentation

◆ GetDefaultColorFormat()

PixelFormat impeller::CapabilitiesGLES::GetDefaultColorFormat ( ) const

overridevirtual

Returns a supported PixelFormat for textures that store 4-channel colors (red/green/blue/alpha).

Implements impeller::Capabilities.

Definition at line 206 of file capabilities_gles.cc.

                                                           {
   return PixelFormat::kR8G8B8A8UNormInt;
 }

References impeller::kR8G8B8A8UNormInt.

◆ GetDefaultDepthStencilFormat()

PixelFormat impeller::CapabilitiesGLES::GetDefaultDepthStencilFormat ( ) const

overridevirtual

Returns a supported PixelFormat for textures that store both a stencil and depth component. This will never return a depth-only or stencil-only texture. Returns PixelFormat::kUnknown if no suitable depth+stencil format was found.

Implements impeller::Capabilities.

Definition at line 214 of file capabilities_gles.cc.

                                                                  {
   return PixelFormat::kD24UnormS8Uint;
 }

References impeller::kD24UnormS8Uint.

◆ GetDefaultGlyphAtlasFormat()

PixelFormat impeller::CapabilitiesGLES::GetDefaultGlyphAtlasFormat ( ) const

overridevirtual

Returns the default pixel format for the alpha bitmap glyph atlas.

   Some backends may use Red channel while others use grey. This
   should not have any impact

Implements impeller::Capabilities.

Definition at line 230 of file capabilities_gles.cc.

                                                                {
   return default_glyph_atlas_format_;
 }

◆ GetDefaultStencilFormat()

PixelFormat impeller::CapabilitiesGLES::GetDefaultStencilFormat ( ) const

overridevirtual

Returns a supported PixelFormat for textures that store stencil information. May include a depth channel if a stencil-only format is not available.

Implements impeller::Capabilities.

Definition at line 210 of file capabilities_gles.cc.

                                                             {
   return PixelFormat::kS8UInt;
 }

References impeller::kS8UInt.

◆ GetMaximumRenderPassAttachmentSize()

ISize impeller::CapabilitiesGLES::GetMaximumRenderPassAttachmentSize ( ) const

overridevirtual

Return the maximum size of a render pass attachment.

Note that this may be smaller than the maximum allocatable texture size.

Implements impeller::Capabilities.

Definition at line 234 of file capabilities_gles.cc.

                                                                  {
   return max_texture_size;
 }

References max_texture_size.

◆ GetMaxTextureUnits()

size_t impeller::CapabilitiesGLES::GetMaxTextureUnits ( ShaderStage stage ) const

Definition at line 149 of file capabilities_gles.cc.

                                                                    {
   switch (stage) {
     case ShaderStage::kVertex:
       return max_vertex_texture_image_units;
     case ShaderStage::kFragment:
       return max_texture_image_units;
     case ShaderStage::kUnknown:
     case ShaderStage::kCompute:
       return 0u;
   }
   FML_UNREACHABLE();
 }

References impeller::kCompute, impeller::kFragment, impeller::kUnknown, impeller::kVertex, max_texture_image_units, and max_vertex_texture_image_units.

◆ GetMinimumUniformAlignment()

size_t impeller::CapabilitiesGLES::GetMinimumUniformAlignment ( ) const

overridevirtual

The minimum alignment of uniform value offsets in bytes.

Implements impeller::Capabilities.

Definition at line 238 of file capabilities_gles.cc.

                                                           {
   return 256;
 }

◆ IsANGLE()

bool impeller::CapabilitiesGLES::IsANGLE ( ) const

Definition at line 218 of file capabilities_gles.cc.

                                      {
   return is_angle_;
 }

◆ IsES()

bool impeller::CapabilitiesGLES::IsES ( ) const

Whether this is an ES GL variant or (if false) desktop GL.

Definition at line 145 of file capabilities_gles.cc.

                                   {
   return is_es_;
 }

◆ operator=() [1/2]

CapabilitiesGLES& impeller::CapabilitiesGLES::operator= ( CapabilitiesGLES && )

delete

◆ operator=() [2/2]

CapabilitiesGLES& impeller::CapabilitiesGLES::operator= ( const CapabilitiesGLES & )

delete

◆ SupportsCompute()

bool impeller::CapabilitiesGLES::SupportsCompute ( ) const

overridevirtual

Whether the context backend supports ComputePass.

Implements impeller::Capabilities.

Definition at line 182 of file capabilities_gles.cc.

                                              {
   return false;
 }

◆ SupportsComputeSubgroups()

bool impeller::CapabilitiesGLES::SupportsComputeSubgroups ( ) const

overridevirtual

Whether the context backend supports configuring ComputePass command subgroups.

Implements impeller::Capabilities.

Definition at line 186 of file capabilities_gles.cc.

                                                       {
   return false;
 }

◆ SupportsDecalSamplerAddressMode()

bool impeller::CapabilitiesGLES::SupportsDecalSamplerAddressMode ( ) const

overridevirtual

Whether the context backend supports SamplerAddressMode::Decal.

Implements impeller::Capabilities.

Definition at line 194 of file capabilities_gles.cc.

                                                              {
   return supports_decal_sampler_address_mode_;
 }

◆ SupportsDeviceTransientTextures()

bool impeller::CapabilitiesGLES::SupportsDeviceTransientTextures ( ) const

overridevirtual

Whether the context backend supports allocating StorageMode::kDeviceTransient (aka "memoryless") textures, which are temporary textures kept in tile memory for the duration of the RenderPass it's attached to.

This feature is especially useful for MSAA and stencils.

Implements impeller::Capabilities.

Definition at line 198 of file capabilities_gles.cc.

                                                              {
   return false;
 }

◆ SupportsExtendedRangeFormats()

bool impeller::CapabilitiesGLES::SupportsExtendedRangeFormats ( ) const

overridevirtual

Whether the XR formats are supported on this device.

This is only ever true for iOS and macOS devices. We may need to revisit this API when approaching wide gamut rendering for Vulkan and GLES.

Implements impeller::Capabilities.

Definition at line 226 of file capabilities_gles.cc.

                                                           {
   return false;
 }

◆ SupportsFramebufferFetch()

bool impeller::CapabilitiesGLES::SupportsFramebufferFetch ( ) const

overridevirtual

Whether the context backend is able to support pipelines with shaders that read from the framebuffer (i.e. pixels that have been written by previous draw calls in the current render pass).

Example of reading from the first color attachment in a GLSL shader: ``` uniform subpassInput subpass_input;

out vec4 frag_color;

void main() { vec4 color = subpassLoad(subpass_input); // Invert the colors drawn to the framebuffer. frag_color = vec4(vec3(1) - color.rgb, color.a); } ```

Implements impeller::Capabilities.

Definition at line 178 of file capabilities_gles.cc.

                                                       {
   return supports_framebuffer_fetch_;
 }

◆ SupportsImplicitResolvingMSAA()

bool impeller::CapabilitiesGLES::SupportsImplicitResolvingMSAA ( ) const

overridevirtual

Whether the context backend supports multisampled rendering to the on-screen surface without requiring an explicit resolve of the MSAA color attachment.

Implements impeller::Capabilities.

Definition at line 166 of file capabilities_gles.cc.

                                                            {
   return supports_implicit_msaa_;
 }

◆ SupportsOffscreenMSAA()

bool impeller::CapabilitiesGLES::SupportsOffscreenMSAA ( ) const

overridevirtual

Whether the context backend supports attaching offscreen MSAA color/stencil textures.

Implements impeller::Capabilities.

Definition at line 162 of file capabilities_gles.cc.

                                                    {
   return supports_offscreen_msaa_;
 }

◆ SupportsPrimitiveRestart()

bool impeller::CapabilitiesGLES::SupportsPrimitiveRestart ( ) const

overridevirtual

Whether primitive restart is supported.

Implements impeller::Capabilities.

Definition at line 222 of file capabilities_gles.cc.

                                                       {
   return false;
 }

◆ SupportsReadFromResolve()

bool impeller::CapabilitiesGLES::SupportsReadFromResolve ( ) const

overridevirtual

Whether the context backend supports binding the current RenderPass attachments. This is supported if the backend can guarantee that attachment textures will not be mutated until the render pass has fully completed.

This is possible because many mobile graphics cards track RenderPass attachment state in intermediary tile memory prior to Storing the pass in the heap allocated attachments on DRAM. Metal's hazard tracking and Vulkan's barriers are granular enough to allow for safely accessing attachment textures prior to storage in the same RenderPass.

Implements impeller::Capabilities.

Definition at line 190 of file capabilities_gles.cc.

                                                      {
   return false;
 }

◆ SupportsSSBO()

bool impeller::CapabilitiesGLES::SupportsSSBO ( ) const

overridevirtual

Whether the context backend supports binding Shader Storage Buffer Objects (SSBOs) to pipelines.

Implements impeller::Capabilities.

Definition at line 170 of file capabilities_gles.cc.

                                           {
   return false;
 }

◆ SupportsTextureToTextureBlits()

bool impeller::CapabilitiesGLES::SupportsTextureToTextureBlits ( ) const

overridevirtual

Whether the context backend supports blitting from one texture region to another texture region (via the relevant BlitPass::AddCopy overloads).

Implements impeller::Capabilities.

Definition at line 174 of file capabilities_gles.cc.

                                                            {
   return supports_texture_to_texture_blits_;
 }

◆ SupportsTriangleFan()

bool impeller::CapabilitiesGLES::SupportsTriangleFan ( ) const

overridevirtual

Whether the primitive type TriangleFan is supported by the backend.

Implements impeller::Capabilities.

Definition at line 202 of file capabilities_gles.cc.

                                                  {
   return true;
 }

Member Data Documentation

◆ max_combined_texture_image_units

size_t impeller::CapabilitiesGLES::max_combined_texture_image_units = 8

Definition at line 38 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ max_cube_map_texture_size

size_t impeller::CapabilitiesGLES::max_cube_map_texture_size = 16

Definition at line 41 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ max_fragment_uniform_vectors

size_t impeller::CapabilitiesGLES::max_fragment_uniform_vectors = 16

Definition at line 44 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ max_renderbuffer_size

size_t impeller::CapabilitiesGLES::max_renderbuffer_size = 1

Definition at line 47 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ max_texture_image_units

size_t impeller::CapabilitiesGLES::max_texture_image_units = 8

Definition at line 50 of file capabilities_gles.h.

Referenced by CapabilitiesGLES(), and GetMaxTextureUnits().

◆ max_texture_size

ISize impeller::CapabilitiesGLES::max_texture_size = ISize{64, 64}

Definition at line 53 of file capabilities_gles.h.

Referenced by CapabilitiesGLES(), and GetMaximumRenderPassAttachmentSize().

◆ max_varying_vectors

size_t impeller::CapabilitiesGLES::max_varying_vectors = 8

Definition at line 56 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ max_vertex_attribs

size_t impeller::CapabilitiesGLES::max_vertex_attribs = 8

Definition at line 59 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ max_vertex_texture_image_units

size_t impeller::CapabilitiesGLES::max_vertex_texture_image_units = 0

Definition at line 62 of file capabilities_gles.h.

Referenced by CapabilitiesGLES(), and GetMaxTextureUnits().

◆ max_vertex_uniform_vectors

size_t impeller::CapabilitiesGLES::max_vertex_uniform_vectors = 128

Definition at line 65 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ max_viewport_dims

ISize impeller::CapabilitiesGLES::max_viewport_dims

Definition at line 68 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ num_compressed_texture_formats

size_t impeller::CapabilitiesGLES::num_compressed_texture_formats = 0

Definition at line 71 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

◆ num_shader_binary_formats

size_t impeller::CapabilitiesGLES::num_shader_binary_formats = 0

Definition at line 74 of file capabilities_gles.h.

Referenced by CapabilitiesGLES().

The documentation for this class was generated from the following files:

impeller/renderer/backend/gles/capabilities_gles.h
impeller/renderer/backend/gles/capabilities_gles.cc

Public Member Functions

Public Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ CapabilitiesGLES() [1/3]

◆ CapabilitiesGLES() [2/3]

◆ CapabilitiesGLES() [3/3]

Member Function Documentation

◆ GetDefaultColorFormat()

◆ GetDefaultDepthStencilFormat()

◆ GetDefaultGlyphAtlasFormat()

◆ GetDefaultStencilFormat()

◆ GetMaximumRenderPassAttachmentSize()

◆ GetMaxTextureUnits()

◆ GetMinimumUniformAlignment()

◆ IsANGLE()

◆ IsES()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ SupportsCompute()

◆ SupportsComputeSubgroups()

◆ SupportsDecalSamplerAddressMode()

◆ SupportsDeviceTransientTextures()

◆ SupportsExtendedRangeFormats()

◆ SupportsFramebufferFetch()

◆ SupportsImplicitResolvingMSAA()

◆ SupportsOffscreenMSAA()

◆ SupportsPrimitiveRestart()

◆ SupportsReadFromResolve()

◆ SupportsSSBO()

◆ SupportsTextureToTextureBlits()

◆ SupportsTriangleFan()

Member Data Documentation

◆ max_combined_texture_image_units

◆ max_cube_map_texture_size

◆ max_fragment_uniform_vectors

◆ max_renderbuffer_size

◆ max_texture_image_units

◆ max_texture_size

◆ max_varying_vectors

◆ max_vertex_attribs

◆ max_vertex_texture_image_units

◆ max_vertex_uniform_vectors

◆ max_viewport_dims

◆ num_compressed_texture_formats

◆ num_shader_binary_formats