D3D11SW

A software implementation of the Direct3D 11 API.

Missing Features

• Tesselation: Hull Shader, Domain Shader
• Deferred contexts

Implemented

• Vertex, Pixel, and Compute shaders (JIT: DXBC → C++ → clang++/MSVC)
• Geometry Shader, Stream output, Adjacency topologies, DrawAuto
• SM4.0/SM5.0 instruction set (arithmetic, integer, bitwise, control flow, atomics)
• Tiled rasterizer with 28.4 fixed-point edge functions
• 2x2 quad pixel shader execution (derivatives, auto-LOD)
• BC compressed textures (BC1, BC2, BC3, BC4, BC5, BC7), BC6H still missing
• Texture sampling: 1D/2D/3D/cube, point/bilinear/trilinear, all address modes
• Anisotropic filtering
• Mipmap chains, GenerateMips, SampleLevel/SampleGrad/SampleBias/SampleCmp
• SRGB support
• Depth/stencil with all comparison functions and stencil ops, HiZ
• Blending with all blend factors/ops, dual-source, logic ops
• Multi-render-target, write masks, clip/cull distances
• SV_ViewportArrayIndex, SV_RenderTargetArrayIndex
• Indexed/instanced/indirect draw and dispatch
• MSAA stubs (apps requesting MSAA should work, rendered as 1x)
• TGSM, barriers, thread pool for compute
• Append/consume buffers

Examples

Screenshots

Triangle

Textured Cube

 

Instanced Cubes

Floor (Aliased vs Mipmapped)

 

Tests

Around 600 tests divided into three categories:

• Unit tests: Device, resources, views, states, formats, shader compilation, draw and compute pipelines
• Golden tests: Pixel-exact comparison against reference images
• Perf tests: Draw and compute benchmarks

References

• D3D11.3 Functional Spec — rasterization rules, fixed-point precision, LOD calculation, texture filtering
• D3D11 API Reference — API contracts, parameter rules, struct/enum definitions
• Parsing DXBC — DXBC container layout
• d3d11TokenizedProgramFormat.hpp (Windows SDK) — opcode definitions, operand encoding, token layout for SM4/SM5 bytecode