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Diffstat (limited to 'src/video_core/geometry_pipeline.cpp')
-rw-r--r-- | src/video_core/geometry_pipeline.cpp | 274 |
1 files changed, 274 insertions, 0 deletions
diff --git a/src/video_core/geometry_pipeline.cpp b/src/video_core/geometry_pipeline.cpp new file mode 100644 index 000000000..b146e2ecb --- /dev/null +++ b/src/video_core/geometry_pipeline.cpp @@ -0,0 +1,274 @@ +// Copyright 2017 Citra Emulator Project +// Licensed under GPLv2 or any later version +// Refer to the license.txt file included. + +#include "video_core/geometry_pipeline.h" +#include "video_core/pica_state.h" +#include "video_core/regs.h" +#include "video_core/renderer_base.h" +#include "video_core/video_core.h" + +namespace Pica { + +/// An attribute buffering interface for different pipeline modes +class GeometryPipelineBackend { +public: + virtual ~GeometryPipelineBackend() = default; + + /// Checks if there is no incomplete data transfer + virtual bool IsEmpty() const = 0; + + /// Checks if the pipeline needs a direct input from index buffer + virtual bool NeedIndexInput() const = 0; + + /// Submits an index from index buffer + virtual void SubmitIndex(unsigned int val) = 0; + + /** + * Submits vertex attributes + * @param input attributes of a vertex output from vertex shader + * @return if the buffer is full and the geometry shader should be invoked + */ + virtual bool SubmitVertex(const Shader::AttributeBuffer& input) = 0; +}; + +// In the Point mode, vertex attributes are sent to the input registers in the geometry shader unit. +// The size of vertex shader outputs and geometry shader inputs are constants. Geometry shader is +// invoked upon inputs buffer filled up by vertex shader outputs. For example, if we have a geometry +// shader that takes 6 inputs, and the vertex shader outputs 2 attributes, it would take 3 vertices +// for one geometry shader invocation. +// TODO: what happens when the input size is not divisible by the output size? +class GeometryPipeline_Point : public GeometryPipelineBackend { +public: + GeometryPipeline_Point(const Regs& regs, Shader::GSUnitState& unit) : regs(regs), unit(unit) { + ASSERT(regs.pipeline.variable_primitive == 0); + ASSERT(regs.gs.input_to_uniform == 0); + vs_output_num = regs.pipeline.vs_outmap_total_minus_1_a + 1; + size_t gs_input_num = regs.gs.max_input_attribute_index + 1; + ASSERT(gs_input_num % vs_output_num == 0); + buffer_cur = attribute_buffer.attr; + buffer_end = attribute_buffer.attr + gs_input_num; + } + + bool IsEmpty() const override { + return buffer_cur == attribute_buffer.attr; + } + + bool NeedIndexInput() const override { + return false; + } + + void SubmitIndex(unsigned int val) override { + UNREACHABLE(); + } + + bool SubmitVertex(const Shader::AttributeBuffer& input) override { + buffer_cur = std::copy(input.attr, input.attr + vs_output_num, buffer_cur); + if (buffer_cur == buffer_end) { + buffer_cur = attribute_buffer.attr; + unit.LoadInput(regs.gs, attribute_buffer); + return true; + } + return false; + } + +private: + const Regs& regs; + Shader::GSUnitState& unit; + Shader::AttributeBuffer attribute_buffer; + Math::Vec4<float24>* buffer_cur; + Math::Vec4<float24>* buffer_end; + unsigned int vs_output_num; +}; + +// In VariablePrimitive mode, vertex attributes are buffered into the uniform registers in the +// geometry shader unit. The number of vertex is variable, which is specified by the first index +// value in the batch. This mode is usually used for subdivision. +class GeometryPipeline_VariablePrimitive : public GeometryPipelineBackend { +public: + GeometryPipeline_VariablePrimitive(const Regs& regs, Shader::ShaderSetup& setup) + : regs(regs), setup(setup) { + ASSERT(regs.pipeline.variable_primitive == 1); + ASSERT(regs.gs.input_to_uniform == 1); + vs_output_num = regs.pipeline.vs_outmap_total_minus_1_a + 1; + } + + bool IsEmpty() const override { + return need_index; + } + + bool NeedIndexInput() const override { + return need_index; + } + + void SubmitIndex(unsigned int val) override { + DEBUG_ASSERT(need_index); + + // The number of vertex input is put to the uniform register + float24 vertex_num = float24::FromFloat32(val); + setup.uniforms.f[0] = Math::MakeVec(vertex_num, vertex_num, vertex_num, vertex_num); + + // The second uniform register and so on are used for receiving input vertices + buffer_cur = setup.uniforms.f + 1; + + main_vertex_num = regs.pipeline.variable_vertex_main_num_minus_1 + 1; + total_vertex_num = val; + need_index = false; + } + + bool SubmitVertex(const Shader::AttributeBuffer& input) override { + DEBUG_ASSERT(!need_index); + if (main_vertex_num != 0) { + // For main vertices, receive all attributes + buffer_cur = std::copy(input.attr, input.attr + vs_output_num, buffer_cur); + --main_vertex_num; + } else { + // For other vertices, only receive the first attribute (usually the position) + *(buffer_cur++) = input.attr[0]; + } + --total_vertex_num; + + if (total_vertex_num == 0) { + need_index = true; + return true; + } + + return false; + } + +private: + bool need_index = true; + const Regs& regs; + Shader::ShaderSetup& setup; + unsigned int main_vertex_num; + unsigned int total_vertex_num; + Math::Vec4<float24>* buffer_cur; + unsigned int vs_output_num; +}; + +// In FixedPrimitive mode, vertex attributes are buffered into the uniform registers in the geometry +// shader unit. The number of vertex per shader invocation is constant. This is usually used for +// particle system. +class GeometryPipeline_FixedPrimitive : public GeometryPipelineBackend { +public: + GeometryPipeline_FixedPrimitive(const Regs& regs, Shader::ShaderSetup& setup) + : regs(regs), setup(setup) { + ASSERT(regs.pipeline.variable_primitive == 0); + ASSERT(regs.gs.input_to_uniform == 1); + vs_output_num = regs.pipeline.vs_outmap_total_minus_1_a + 1; + ASSERT(vs_output_num == regs.pipeline.gs_config.stride_minus_1 + 1); + size_t vertex_num = regs.pipeline.gs_config.fixed_vertex_num_minus_1 + 1; + buffer_cur = buffer_begin = setup.uniforms.f + regs.pipeline.gs_config.start_index; + buffer_end = buffer_begin + vs_output_num * vertex_num; + } + + bool IsEmpty() const override { + return buffer_cur == buffer_begin; + } + + bool NeedIndexInput() const override { + return false; + } + + void SubmitIndex(unsigned int val) override { + UNREACHABLE(); + } + + bool SubmitVertex(const Shader::AttributeBuffer& input) override { + buffer_cur = std::copy(input.attr, input.attr + vs_output_num, buffer_cur); + if (buffer_cur == buffer_end) { + buffer_cur = buffer_begin; + return true; + } + return false; + } + +private: + const Regs& regs; + Shader::ShaderSetup& setup; + Math::Vec4<float24>* buffer_begin; + Math::Vec4<float24>* buffer_cur; + Math::Vec4<float24>* buffer_end; + unsigned int vs_output_num; +}; + +GeometryPipeline::GeometryPipeline(State& state) : state(state) {} + +GeometryPipeline::~GeometryPipeline() = default; + +void GeometryPipeline::SetVertexHandler(Shader::VertexHandler vertex_handler) { + this->vertex_handler = vertex_handler; +} + +void GeometryPipeline::Setup(Shader::ShaderEngine* shader_engine) { + if (!backend) + return; + + this->shader_engine = shader_engine; + shader_engine->SetupBatch(state.gs, state.regs.gs.main_offset); +} + +void GeometryPipeline::Reconfigure() { + ASSERT(!backend || backend->IsEmpty()); + + if (state.regs.pipeline.use_gs == PipelineRegs::UseGS::No) { + backend = nullptr; + return; + } + + ASSERT(state.regs.pipeline.use_gs == PipelineRegs::UseGS::Yes); + + // The following assumes that when geometry shader is in use, the shader unit 3 is configured as + // a geometry shader unit. + // TODO: what happens if this is not true? + ASSERT(state.regs.pipeline.gs_unit_exclusive_configuration == 1); + ASSERT(state.regs.gs.shader_mode == ShaderRegs::ShaderMode::GS); + + state.gs_unit.ConfigOutput(state.regs.gs); + + ASSERT(state.regs.pipeline.vs_outmap_total_minus_1_a == + state.regs.pipeline.vs_outmap_total_minus_1_b); + + switch (state.regs.pipeline.gs_config.mode) { + case PipelineRegs::GSMode::Point: + backend = std::make_unique<GeometryPipeline_Point>(state.regs, state.gs_unit); + break; + case PipelineRegs::GSMode::VariablePrimitive: + backend = std::make_unique<GeometryPipeline_VariablePrimitive>(state.regs, state.gs); + break; + case PipelineRegs::GSMode::FixedPrimitive: + backend = std::make_unique<GeometryPipeline_FixedPrimitive>(state.regs, state.gs); + break; + default: + UNREACHABLE(); + } +} + +bool GeometryPipeline::NeedIndexInput() const { + if (!backend) + return false; + return backend->NeedIndexInput(); +} + +void GeometryPipeline::SubmitIndex(unsigned int val) { + backend->SubmitIndex(val); +} + +void GeometryPipeline::SubmitVertex(const Shader::AttributeBuffer& input) { + if (!backend) { + // No backend means the geometry shader is disabled, so we send the vertex shader output + // directly to the primitive assembler. + vertex_handler(input); + } else { + if (backend->SubmitVertex(input)) { + shader_engine->Run(state.gs, state.gs_unit); + + // The uniform b15 is set to true after every geometry shader invocation. This is useful + // for the shader to know if this is the first invocation in a batch, if the program set + // b15 to false first. + state.gs.uniforms.b[15] = true; + } + } +} + +} // namespace Pica |