QuakeSpasm for old Macs

A fork of QuakeSpasm tuned for six old Macs spanning 1999 to 2019. One fat 3-architecture Mach-O binary boots into a per-machine config and turns on the best visual stack each GPU can afford while staying above its playability floor.

# Headline gains

Best timedemo improvements per machine, before-and-after on the same hardware (median of three runs). Every "after" cell is the v7 build with translucent water, alias-model shadows and emissive dynamic lights enabled.

The 1999 G3 going from 5.10 fps (unplayable) to 19.80 fps (playable) at 1024×768 is the headline number, and that's with the full visual stack on. Quicksilver and the Lion mini joined mid-project so don't have a clean baseline.

# Get the build

The current release is v1.1-round-v7.

The fat universal binary runs unchanged on Panther 10.3.9 through Sequoia 15.7. dyld picks the right slice on each host; the engine then queries hw.model at boot and loads the matching autoexec-<machine>.cfg.

# Features

• One fat 3-architecture Mach-O (PPC 750 + PPC 7400 + x86_64) for every supported Mac, no per-machine reinstall
• Per-machine autoexec configs that pick the best visual stack each GPU can carry: GLSL water on the programmable G4s, distance-gated dynamic lights on the G3, framebuffer-clear skip on five of six machines
• Translucent water, lava, slime and teleporters on every machine including the 1999 G3
• Alias-model shadows on every machine, with runtime distance gates (r_shadow_distance) on the G4 trio and Lion
• Emissive-fullbright dynamic lights — wall buttons, computer screens, fluorescent fixtures and tech panels cast coloured light into the room (new cvar r_emissive_lights, on by default everywhere with per-GPU radius and max tuning)
• Engine-side fix for the long-standing X-ray watervis bug on un-watervis'd id1 maps
• AltiVec replacements for the alias-model lerp and 16-bit sound mixer on G4 targets
• On-pickup HUD blink restored (regression in upstream, fix at sbar.c:657)
• Latent null-deref, signed-shift UB and unchecked-allocation bugs surfaced and fixed via modern static analysis (cppcheck, clang-tidy, scan-build, gcc -fanalyzer, ASan, UBSan) against a Linux build target compiling the same source
• SSH-based remote-recovery script (qsreboot.sh) that survives the Rage 128 LUT corruption Panther leaves on hard kills
• Parallel six-machine bench loop with three-run median, atomic CSV row appends (parallel-bench.sh) and an unattended screenshot harness (screenshot.sh)

# The bench

# Tech stack

# Architecture

An Ubuntu workstation orchestrates the six Macs over SSH. The Lion mini does double duty as both a bench target and the cross-build host for every PPC binary — it's the last Mac Apple shipped with PPC-targeting GCC 4.0.1 in /usr/bin.

Three toolchains converge into one fat Mach-O via lipo -create. No CI, no containers — rsync + ssh + scp on top of make.

The bench loop is the same on every machine: deploy, launch with the per-arch autoexec, poll qconsole.log for the timedemo result, append a row to a rolling CSV. Three runs per cell; the first is treated as warm-up and dropped.

# Frames per second across the rack

Round v7 wrap full-grid bench at commit f2df151d. Median of three runs per cell.

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