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Diffstat (limited to 'source/blender/gpu/metal/mtl_shader_interface.hh')
| -rw-r--r-- | source/blender/gpu/metal/mtl_shader_interface.hh | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/source/blender/gpu/metal/mtl_shader_interface.hh b/source/blender/gpu/metal/mtl_shader_interface.hh new file mode 100644 index 00000000000..0f04c04031d --- /dev/null +++ b/source/blender/gpu/metal/mtl_shader_interface.hh @@ -0,0 +1,267 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +/** \file + * \ingroup gpu + */ + +#pragma once + +#include "MEM_guardedalloc.h" + +#include "BLI_vector.hh" + +#include "gpu_shader_interface.hh" +#include "mtl_capabilities.hh" +#include "mtl_shader_interface_type.hh" + +#include "GPU_common.h" +#include "GPU_common_types.h" +#include "GPU_texture.h" +#include "gpu_texture_private.hh" +#include <Metal/Metal.h> +#include <functional> + +namespace blender::gpu { + +/* MTLShaderInterface describes the layout and properties of a given shader, + * including input and output bindings, and any special properties or modes + * that the shader may require. + * + * -- Shader input/output bindings -- + * + * We require custom datastructures for the binding information in Metal. + * This is because certain bindings contain and require more information to + * be stored than can be tracked solely within the `ShaderInput` struct. + * e.g. data sizes and offsets. + * + * Upon interface completion, `prepare_common_shader_inputs` is used to + * populate the global ShaderInput* array to enable correct functionality + * of shader binding location lookups. These returned locations act as indices + * into the arrays stored here in the MTLShaderInterace, such that extraction + * of required information can be performed within the backend. + * + * e.g. `int loc = GPU_shader_get_uniform(...)` + * `loc` will match the index into the MTLShaderUniform uniforms_[] array + * to fetch the required Metal specific information. + * + * + * + * -- Argument Buffers and Argument Encoders -- + * + * We can use ArgumentBuffers (AB's) in Metal to extend the resource bind limitations + * by providing bindless support. + * + * Argument Buffers are used for sampler bindings when the builtin + * sampler limit of 16 is exceeded, as in all cases for Blender, + * each individual texture is associated with a given sampler, and this + * lower limit would otherwise reduce the total availability of textures + * used in shaders. + * + * In future, argument buffers may be extended to support other resource + * types, if overall bind limits are ever increased within Blender. + * + * The ArgumentEncoder cache used to store the generated ArgumentEncoders for a given + * shader permutation. The ArgumentEncoder is the resource used to write resource binding + * information to a specified buffer, and is unique to the shader's resource interface. + */ + +enum class ShaderStage : uint32_t { + VERTEX = 1 << 0, + FRAGMENT = 1 << 1, + BOTH = (ShaderStage::VERTEX | ShaderStage::FRAGMENT), +}; +ENUM_OPERATORS(ShaderStage, ShaderStage::BOTH); + +inline uint get_shader_stage_index(ShaderStage stage) +{ + switch (stage) { + case ShaderStage::VERTEX: + return 0; + case ShaderStage::FRAGMENT: + return 1; + default: + BLI_assert_unreachable(); + return 0; + } + return 0; +} + +/* Shader input/output binding information. */ +struct MTLShaderInputAttribute { + uint32_t name_offset; + MTLVertexFormat format; + uint32_t index; + uint32_t location; + uint32_t size; + uint32_t buffer_index; + uint32_t offset; + /* For attributes of Matrix/array types, we need to insert "fake" attributes for + * each element, as matrix types are not natively supported. + * + * > 1 if matrix/arrays are used, specifying number of elements. + * = 1 for non-matrix types + * = 0 if used as a dummy slot for "fake" matrix attributes. */ + uint32_t matrix_element_count; +}; + +struct MTLShaderUniformBlock { + uint32_t name_offset; + uint32_t size = 0; + /* Buffer resouce bind index in shader [[buffer(index)]]. */ + uint32_t buffer_index; + + /* Tracking for manual uniform addition. */ + uint32_t current_offset; + ShaderStage stage_mask; +}; + +struct MTLShaderUniform { + uint32_t name_offset; + /* Index of `MTLShaderUniformBlock` this uniform belongs to. */ + uint32_t size_in_bytes; + uint32_t byte_offset; + eMTLDataType type; + uint32_t array_len; +}; + +struct MTLShaderTexture { + bool used; + uint32_t name_offset; + /* Texture resource bind slot in shader [[texture(n)]]. */ + int slot_index; + eGPUTextureType type; + ShaderStage stage_mask; +}; + +struct MTLShaderSampler { + uint32_t name_offset; + /* Sampler resource bind slot in shader [[sampler(n)]]. */ + uint32_t slot_index = 0; +}; + +/* Utility Functions. */ +MTLVertexFormat mtl_datatype_to_vertex_type(eMTLDataType type); + +/** + * Implementation of Shader interface for Metal Backend. + **/ +class MTLShaderInterface : public ShaderInterface { + + private: + /* Argument encoders caching. + * Static size is based on common input permutation variations. */ + static const int ARGUMENT_ENCODERS_CACHE_SIZE = 3; + struct ArgumentEncoderCacheEntry { + id<MTLArgumentEncoder> encoder; + int buffer_index; + }; + ArgumentEncoderCacheEntry arg_encoders_[ARGUMENT_ENCODERS_CACHE_SIZE] = {}; + + /* Vertex input Attribues. */ + uint32_t total_attributes_; + uint32_t total_vert_stride_; + MTLShaderInputAttribute attributes_[MTL_MAX_VERTEX_INPUT_ATTRIBUTES]; + + /* Uniforms. */ + uint32_t total_uniforms_; + MTLShaderUniform uniforms_[MTL_MAX_UNIFORMS_PER_BLOCK]; + + /* Uniform Blocks. */ + uint32_t total_uniform_blocks_; + MTLShaderUniformBlock ubos_[MTL_MAX_UNIFORM_BUFFER_BINDINGS]; + MTLShaderUniformBlock push_constant_block_; + + /* Textures. */ + /* Textures support explicit binding indices, so some texture slots + * remain unused. */ + uint32_t total_textures_; + int max_texture_index_; + MTLShaderTexture textures_[MTL_MAX_TEXTURE_SLOTS]; + + /* Whether argument buffers are used for sampler bindings. */ + bool sampler_use_argument_buffer_; + int sampler_argument_buffer_bind_index_vert_; + int sampler_argument_buffer_bind_index_frag_; + + /* Attribute Mask. */ + uint32_t enabled_attribute_mask_; + + /* Debug. */ + char name[256]; + + public: + MTLShaderInterface(const char *name); + ~MTLShaderInterface(); + + void init(); + void add_input_attribute(uint32_t name_offset, + uint32_t attribute_location, + MTLVertexFormat format, + uint32_t buffer_index, + uint32_t size, + uint32_t offset, + int matrix_element_count = 1); + uint32_t add_uniform_block(uint32_t name_offset, + uint32_t buffer_index, + uint32_t size, + ShaderStage stage_mask = ShaderStage::BOTH); + void add_uniform(uint32_t name_offset, eMTLDataType type, int array_len = 1); + void add_texture(uint32_t name_offset, + uint32_t texture_slot, + eGPUTextureType tex_binding_type, + ShaderStage stage_mask = ShaderStage::FRAGMENT); + void add_push_constant_block(uint32_t name_offset); + + /* Resolve and cache locations of builtin uniforms and uniform blocks. */ + void map_builtins(); + void set_sampler_properties(bool use_argument_buffer, + uint32_t argument_buffer_bind_index_vert, + uint32_t argument_buffer_bind_index_frag); + + /* Prepare ShaderInput interface for binding resolution. */ + void prepare_common_shader_inputs(); + + /* Fetch Uniforms. */ + const MTLShaderUniform &get_uniform(uint index) const; + uint32_t get_total_uniforms() const; + + /* Fetch Uniform Blocks. */ + const MTLShaderUniformBlock &get_uniform_block(uint index) const; + uint32_t get_total_uniform_blocks() const; + bool has_uniform_block(uint32_t block_index) const; + uint32_t get_uniform_block_size(uint32_t block_index) const; + + /* Push constant uniform data block should always be available. */ + const MTLShaderUniformBlock &get_push_constant_block() const; + + /* Fetch textures. */ + const MTLShaderTexture &get_texture(uint index) const; + uint32_t get_total_textures() const; + uint32_t get_max_texture_index() const; + bool get_use_argument_buffer_for_samplers(int *vertex_arg_buffer_bind_index, + int *fragment_arg_buffer_bind_index) const; + + /* Fetch Attributes. */ + const MTLShaderInputAttribute &get_attribute(uint index) const; + uint32_t get_total_attributes() const; + uint32_t get_total_vertex_stride() const; + uint32_t get_enabled_attribute_mask() const; + + /* Name buffer fetching. */ + const char *get_name_at_offset(uint32_t offset) const; + + /* Interface name. */ + const char *get_name() const + { + return this->name; + } + + /* Argument buffer encoder management. */ + id<MTLArgumentEncoder> find_argument_encoder(int buffer_index) const; + + void insert_argument_encoder(int buffer_index, id encoder); + + MEM_CXX_CLASS_ALLOC_FUNCS("MTLShaderInterface"); +}; + +} // namespace blender::gpu |