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33-post thread, 13 PNGs, the canonical 'shader dev' walkthrough. Reads FXAA 3.11 / FSR1 / Unity STP, names the permutations pattern (32-bit / packed 16-bit / implicit mediump / MIN-MAX sampling). DXIL no bitfield ops vs SPIR-V (HLSL pre-processing on non-Xbox = fail). 16-bit perf: don't permute from 32-bit float constants (instant PC perf death), alias FP16 as UINT32 binary blobs. Designing shaders like GPU assembly, AMD RDNA2 as the design target. Defines map logic to associated instruction (fma, bitfieldExtract), all-ints-unsigned convention with SI1_I1()-style bitcast macros, 3-letter type macros. Compiler pattern-match bugs: tried always-UINT4 bitcast, didn't work; native types except waveops. Argument passing SSA state explosion: inout uint4[16] (all VGPRs) didn't end well - shader langs support globals, use them. Next level: mostly globals with type- bitcast aliasing; x86-64 union-of-structs-on-globals as the GPU calling ABI. Foundation for the SPIR-V-from-data + cart-file work (Aug 2025).