raptorreplica
214789fe87
Engine changes vs the vendored upstream (full ledger in docs/upstream-patches.md): - Assets: replace the encrypted FILE000N.GLB archives with a catalog of pre-decrypted loose files (data/INDEX); GLB_SlotItems() drives mission-pack / registered-version detection; payloads never run the GLB cipher at runtime. - Platform: Linux/SDL2/ALSA only; Android, MSVC/MinGW, macOS packaging, bundled Windows SDL2 SDKs and the ENDOOM exit screen are gone; EXIT_Error now prints before exiting. - Rendering: decouple presentation from simulation -- sim stays at the original 70/3 Hz, frames render interpolated at display rate (player, map scroll, enemies, shots, bonuses, anims, shadows); menus keep 70 Hz pacing; vsync with a delay-guard fallback. - QoL: borderless window mode (Video/borderless), no menu cursor snapping onto default buttons. Fix four regressions from the render split: - Shield bars never redrew: RAP_ThinkStats latches g_oldshield each sim step before RAP_DisplayStats' dirty check could fire. Bars now draw unconditionally per rendered frame; g_oldsuper deleted, g_oldshield kept as sim-side damage-detection state only. - Dying ships despawned without exploding: the render loop never called ANIMS_DisplayHigh(); most air-death explosions register HIGH_AIR. Restored between the player and enemy shots, as upstream orders it. - Laser turret broke: reusing doneflag as a draw marker (it is hit/retire game state, and the turret retire path never frees its shot) hid the beam on hitting ticks and leaked one SHOTS pool slot per fire until no weapon could shoot. S_LINE tracers now carry an age counter: one Think pass, every render of their birth step, purged at the top of the next Think. - Muzzle flash was cleared per rendered frame, making it invisible at display refresh rates; now cleared once per simulation step.
2.6 KiB
2.6 KiB
GLB archive format
The original game ships its data as FILE0000.GLB ... FILE0006.GLB,
produced by the "GLib" library bundled with the commercial source. The
format below was reverse-engineered from raptor/src/glbapi.cpp (upstream
loader) and verified against all seven shipped archives (6449 items total).
Container
A GLB file is a flat sequence of 28-byte records:
typedef struct {
uint32_t opt; // 0 = plain payload, 1 = encrypted payload
uint32_t offset; // payload offset in the file
uint32_t filesize; // payload size in bytes
char name[16]; // NUL-padded item name, e.g. "GENMIDI_OP2"
} KEYFILE; // little-endian fields
- Record 0 is the header. Its
offsetfield holds the item count; its other fields are unused. - Records
1 .. countare the item descriptor table, starting at byte 28. - Item payloads live at each descriptor's
offset,filesizebytes long. - Names are unique per archive only in practice; duplicates (e.g. dozens of
CHASE_AGX, thousands of emptyunnamedlabels) are common. - Descriptor entries with
filesize == 0are labels/placeholders.
Cipher
Every record and every payload flagged opt == 1 is scrambled with a
rolling additive cipher keyed on the ASCII string 32768GLB, seeded at 25
(SEED in glbapi.h):
kidx = 25 % len(key) # 25 % 8 = 1
prev = key[kidx]
# decrypt (GLB_DeCrypt):
for each byte b:
out = (b - key[kidx] - prev) mod 256
prev = b # chain uses the CIPHERTEXT byte
kidx = (kidx + 1) mod len(key)
# encrypt (GLB_EnCrypt) is the inverse:
out = (b + key[kidx] + prev) mod 256
prev = out # chain uses the PLAINTEXT byte
Notes:
- The cipher state resets per record and per payload.
- The original C uses signed
char; the stored byte equals the mathematical result mod 256 either way, so unsigned arithmetic is byte-exact. - Payload encryption is independent of descriptor encryption: an archive typically mixes plain and encrypted items.
Verification
tools/glbextract.py implements this format. Correctness was checked
against known payloads:
GENMIDI_OP2starts with the DMX magic#OPL_II#(11908 bytes)PALETTE_DATis exactly 768 bytes (256 x RGB)DMXGUS_INIdecodes to readable INI text- item counts per archive match the id ranges in
raptor/src/fileids.h(e.g. slot 0: 230 items, last id0x0e5) - every payload lies within its archive's bounds (extractor warns otherwise)
See also
- asset-pipeline.md — how archives become
data/ tools/glbextract.py— reference implementation (Python, stdlib only)