From 3f69c2039de1c3d084ac2c9eb0aa9315490346bf Mon Sep 17 00:00:00 2001 From: bunnei Date: Tue, 21 Jul 2015 19:38:59 -0400 Subject: Shader: Define a common interface for running vertex shader programs. --- src/video_core/shader/shader.h | 163 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 163 insertions(+) create mode 100644 src/video_core/shader/shader.h (limited to 'src/video_core/shader/shader.h') diff --git a/src/video_core/shader/shader.h b/src/video_core/shader/shader.h new file mode 100644 index 000000000..38c00768d --- /dev/null +++ b/src/video_core/shader/shader.h @@ -0,0 +1,163 @@ +// Copyright 2015 Citra Emulator Project +// Licensed under GPLv2 or any later version +// Refer to the license.txt file included. + +#pragma once + +#include +#include + +#include "common/common_funcs.h" +#include "common/common_types.h" +#include "common/vector_math.h" + +#include "video_core/pica.h" + +using nihstro::RegisterType; +using nihstro::SourceRegister; +using nihstro::DestRegister; + +namespace Pica { + +namespace Shader { + +struct InputVertex { + Math::Vec4 attr[16]; +}; + +struct OutputVertex { + OutputVertex() = default; + + // VS output attributes + Math::Vec4 pos; + Math::Vec4 dummy; // quaternions (not implemented, yet) + Math::Vec4 color; + Math::Vec2 tc0; + Math::Vec2 tc1; + float24 pad[6]; + Math::Vec2 tc2; + + // Padding for optimal alignment + float24 pad2[4]; + + // Attributes used to store intermediate results + + // position after perspective divide + Math::Vec3 screenpos; + float24 pad3; + + // Linear interpolation + // factor: 0=this, 1=vtx + void Lerp(float24 factor, const OutputVertex& vtx) { + pos = pos * factor + vtx.pos * (float24::FromFloat32(1) - factor); + + // TODO: Should perform perspective correct interpolation here... + tc0 = tc0 * factor + vtx.tc0 * (float24::FromFloat32(1) - factor); + tc1 = tc1 * factor + vtx.tc1 * (float24::FromFloat32(1) - factor); + tc2 = tc2 * factor + vtx.tc2 * (float24::FromFloat32(1) - factor); + + screenpos = screenpos * factor + vtx.screenpos * (float24::FromFloat32(1) - factor); + + color = color * factor + vtx.color * (float24::FromFloat32(1) - factor); + } + + // Linear interpolation + // factor: 0=v0, 1=v1 + static OutputVertex Lerp(float24 factor, const OutputVertex& v0, const OutputVertex& v1) { + OutputVertex ret = v0; + ret.Lerp(factor, v1); + return ret; + } +}; +static_assert(std::is_pod::value, "Structure is not POD"); +static_assert(sizeof(OutputVertex) == 32 * sizeof(float), "OutputVertex has invalid size"); + +/** + * This structure contains the state information that needs to be unique for a shader unit. The 3DS + * has four shader units that process shaders in parallel. At the present, Citra only implements a + * single shader unit that processes all shaders serially. Putting the state information in a struct + * here will make it easier for us to parallelize the shader processing later. + */ +struct UnitState { + // The registers are accessed by the shader JIT using SSE instructions, and are therefore + // required to be 16-byte aligned. + Math::Vec4 MEMORY_ALIGNED16(input_registers[16]); + Math::Vec4 MEMORY_ALIGNED16(output_registers[16]); + Math::Vec4 MEMORY_ALIGNED16(temporary_registers[16]); + + u32 program_counter; + bool conditional_code[2]; + + // Two Address registers and one loop counter + // TODO: How many bits do these actually have? + s32 address_registers[3]; + + enum { + INVALID_ADDRESS = 0xFFFFFFFF + }; + + struct CallStackElement { + u32 final_address; // Address upon which we jump to return_address + u32 return_address; // Where to jump when leaving scope + u8 repeat_counter; // How often to repeat until this call stack element is removed + u8 loop_increment; // Which value to add to the loop counter after an iteration + // TODO: Should this be a signed value? Does it even matter? + u32 loop_address; // The address where we'll return to after each loop iteration + }; + + // TODO: Is there a maximal size for this? + boost::container::static_vector call_stack; + + struct { + u32 max_offset; // maximum program counter ever reached + u32 max_opdesc_id; // maximum swizzle pattern index ever used + } debug; + + static int InputOffset(const SourceRegister& reg) { + switch (reg.GetRegisterType()) { + case RegisterType::Input: + return (int)offsetof(UnitState, input_registers) + reg.GetIndex()*sizeof(Math::Vec4); + + case RegisterType::Temporary: + return (int)offsetof(UnitState, temporary_registers) + reg.GetIndex()*sizeof(Math::Vec4); + + default: + UNREACHABLE(); + return 0; + } + } + + static int OutputOffset(const DestRegister& reg) { + switch (reg.GetRegisterType()) { + case RegisterType::Output: + return (int)offsetof(UnitState, output_registers) + reg.GetIndex()*sizeof(Math::Vec4); + + case RegisterType::Temporary: + return (int)offsetof(UnitState, temporary_registers) + reg.GetIndex()*sizeof(Math::Vec4); + + default: + UNREACHABLE(); + return 0; + } + } +}; + +/** + * Performs any shader unit setup that only needs to happen once per shader (as opposed to once per + * vertex, which would happen within the `Run` function). + * @param state Shader unit state, must be setup per shader and per shader unit + */ +void Setup(UnitState& state); + +/** + * Runs the currently setup shader + * @param state Shader unit state, must be setup per shader and per shader unit + * @param input Input vertex into the shader + * @param num_attributes The number of vertex shader attributes + * @return The output vertex, after having been processed by the vertex shader + */ +OutputVertex Run(UnitState& state, const InputVertex& input, int num_attributes); + +} // namespace Shader + +} // namespace Pica -- cgit v1.2.3