#include <vertex_descriptor_mtl.h>

Public Member Functions
	VertexDescriptorMTL ()

	~VertexDescriptorMTL ()

bool	SetStageInputsAndLayout (const std::vector< ShaderStageIOSlot > &inputs, const std::vector< ShaderStageBufferLayout > &layouts)

MTLVertexDescriptor *	GetMTLVertexDescriptor () const

Detailed Description

Definition at line 17 of file vertex_descriptor_mtl.h.

Constructor & Destructor Documentation

◆ VertexDescriptorMTL()

impeller::VertexDescriptorMTL::VertexDescriptorMTL ( )

default

◆ ~VertexDescriptorMTL()

impeller::VertexDescriptorMTL::~VertexDescriptorMTL ( )

default

Member Function Documentation

◆ GetMTLVertexDescriptor()

MTLVertexDescriptor * impeller::VertexDescriptorMTL::GetMTLVertexDescriptor ( ) const

Definition at line 123 of file vertex_descriptor_mtl.mm.

                                                                        {
   return descriptor_;
 }

Referenced by impeller::GetMTLRenderPipelineDescriptor().

◆ SetStageInputsAndLayout()

bool impeller::VertexDescriptorMTL::SetStageInputsAndLayout	(	const std::vector< ShaderStageIOSlot > &	inputs,
		const std::vector< ShaderStageBufferLayout > &	layouts
	)

Definition at line 87 of file vertex_descriptor_mtl.mm.

                                                        {
   auto descriptor = descriptor_ = [MTLVertexDescriptor vertexDescriptor];
  
   // TODO(jonahwilliams): its odd that we offset buffers from the max index on
   // metal but not on GLES or Vulkan. We should probably consistently start
   // these at zero?
   for (size_t i = 0; i < inputs.size(); i++) {
     const auto& input = inputs[i];
     auto vertex_format = ReadStageInputFormat(input);
     if (vertex_format == MTLVertexFormatInvalid) {
       VALIDATION_LOG << "Format for input " << input.name << " not supported.";
       return false;
     }
     auto attrib = descriptor.attributes[input.location];
     attrib.format = vertex_format;
     attrib.offset = input.offset;
     attrib.bufferIndex =
         VertexDescriptor::kReservedVertexBufferIndex - input.binding;
   }
  
   for (size_t i = 0; i < layouts.size(); i++) {
     const auto& layout = layouts[i];
     auto vertex_layout =
         descriptor.layouts[VertexDescriptor::kReservedVertexBufferIndex -
                            layout.binding];
     vertex_layout.stride = layout.stride;
     vertex_layout.stepRate = 1u;
     vertex_layout.stepFunction = layout.input_rate == VertexInputRate::kInstance
                                      ? MTLVertexStepFunctionPerInstance
                                      : MTLVertexStepFunctionPerVertex;
   }
   return true;
 }

References impeller::kInstance, impeller::VertexDescriptor::kReservedVertexBufferIndex, impeller::ReadStageInputFormat(), and VALIDATION_LOG.