A low‐level 2D sprite simulation engine built from scratch to explore modern Single Instruction, Multiple Data (SIMD) architectures, unified memory, and high‐performance graphics pipelines.
Inspired by the hardware architecture of the Game Boy Advance (GBA) and the execution constraints of legacy Game Pak buses, this project bridges classic sprite management with techniques tailored for Apple Silicon (M2 Max / AArch64).
To maximize cache‐line efficiency, entities are managed inside a unified channel_pool. Rather than allocating individual entity objects, fields are partitioned into contiguous, linear memory channels (x_pos, y_vel, z_new_pos, etc.).
- Zero‐Copy GPU Sharing: Backed by
MTL::ResourceStorageModeShared, the CPU‐side physics subsystem writes directly to unified memory space, making transforms immediately visible to the GPU. - Strict Cache Alignment: Memory reallocations automatically round up each channel’s internal capacity to 128‐byte alignment, ensuring its Neon vector field fit into a cache lane boundaries.
- The engine loads transformations via 128‐bit vector lanes (
vld1q_f32) and updates states using hardware fused multiply‐accumulate (vfmaq_f32) operations.
- Language Standard: C++23 working features (leveraging
<ranges>, concepts, and compile‐time evaluation constraints). - Compiler: Native Toolchain (
Apple Clang) configured with high‐optimization overrides (-O3 -flto). - Graphics API: Pure C++ Metal bindings via
metal-cpp(zero Objective‑C overhead during hot paths). - Assembly / Intrinsic Targets: AArch64 Vector Architecture (
<arm_neon.h>).
- Bit Packed System Blobs: Custom metadata masking limits allocation footprints, mirroring vintage hardware registries like OAM.
- Fixed Timestep Simulation: Disconnects rendering update cadences from physical tick integrations to ensure deterministic collision stability, backed by strict clamp protections to prevent framerate “cascades.”
- Spatial Hashing: Accelerates proximity queries by mapping dense grid arrays to linear memory lookups, narrowing the collision search space.