ref: 3e7b18472cba687a04f6cd9be66ad531ed24283c
dir: /src/modloaders/ft2_load_stm.c/
// Scream Tracker 2 STM loader
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include "../ft2_header.h"
#include "../ft2_module_loader.h"
#include "../ft2_sample_ed.h"
#include "../ft2_tables.h"
#include "../ft2_sysreqs.h"
#ifdef _MSC_VER // please don't mess with these structs!
#pragma pack(push)
#pragma pack(1)
#endif
typedef struct songSTMinstrHeaderTyp_t
{
char name[12];
uint8_t nul, insDisk;
uint16_t reserved1, len, repS, repE;
uint8_t vol, reserved2;
uint16_t rate;
int32_t reserved3;
uint16_t paraLen;
}
#ifdef __GNUC__
__attribute__ ((packed))
#endif
songSTMinstrHeaderTyp;
typedef struct songSTMHeaderTyp_t
{
char name[20], sig[8];
uint8_t id1a, typ;
uint8_t verMajor, verMinor;
uint8_t tempo, ap, vol, reserved[13];
songSTMinstrHeaderTyp instr[31];
uint8_t songTab[128];
}
#ifdef __GNUC__
__attribute__ ((packed))
#endif
songSTMHeaderTyp;
#ifdef _MSC_VER
#pragma pack(pop)
#endif
static const uint8_t stmEff[16] = { 0, 0, 11, 0, 10, 2, 1, 3, 4, 7, 0, 5, 6, 0, 0, 0 };
static uint8_t stmTempoToBPM(uint8_t tempo);
bool loadSTM(FILE *f, uint32_t filesize)
{
uint8_t typ, tempo, pattBuff[1024];
int16_t i, j, k, ap, tmp;
uint16_t a;
tonTyp *ton;
sampleTyp *s;
songSTMHeaderTyp h_STM;
tmpLinearPeriodsFlag = false; // use Amiga periods
if (filesize < sizeof (h_STM))
{
loaderMsgBox("Error: This file is either not a module, or is not supported.");
return false;
}
if (fread(&h_STM, 1, sizeof (h_STM), f) != sizeof (h_STM))
{
loaderMsgBox("Error: This file is either not a module, or is not supported.");
return false;
}
if (h_STM.verMinor == 0 || h_STM.typ != 2)
{
loaderMsgBox("Error loading STM: Incompatible module!");
return false;
}
songTmp.antChn = 4;
memcpy(songTmp.songTab, h_STM.songTab, 128);
i = 0;
while (i < 128 && songTmp.songTab[i] < 99) i++;
songTmp.len = i + (i == 0);
if (songTmp.len < 255)
memset(&songTmp.songTab[songTmp.len], 0, 256 - songTmp.len);
memcpy(songTmp.name, h_STM.name, 20);
tempo = h_STM.tempo;
if (h_STM.verMinor < 21)
tempo = ((tempo / 10) << 4) + (tempo % 10);
if (tempo == 0)
tempo = 96;
songTmp.initialTempo = songTmp.tempo = CLAMP(h_STM.tempo >> 4, 1, 31);
songTmp.speed = stmTempoToBPM(tempo);
if (h_STM.verMinor > 10)
songTmp.globVol = MIN(h_STM.vol, 64);
ap = h_STM.ap;
for (i = 0; i < ap; i++)
{
if (!allocateTmpPatt(i, 64))
{
loaderMsgBox("Not enough memory!");
return false;
}
if (fread(pattBuff, 64 * 4 * 4, 1, f) != 1)
{
loaderMsgBox("General I/O error during loading!");
return false;
}
a = 0;
for (j = 0; j < 64; j++)
{
for (k = 0; k < 4; k++)
{
ton = &pattTmp[i][(j * MAX_VOICES) + k];
if (pattBuff[a] == 254)
{
ton->ton = 97;
}
else if (pattBuff[a] < 96)
{
ton->ton = (12 * (pattBuff[a] >> 4)) + (25 + (pattBuff[a] & 0x0F));
if (ton->ton > 96)
ton->ton = 0;
}
else
{
ton->ton = 0;
}
ton->instr = pattBuff[a + 1] >> 3;
typ = (pattBuff[a + 1] & 7) + ((pattBuff[a + 2] & 0xF0) >> 1);
if (typ <= 64)
ton->vol = typ + 0x10;
ton->eff = pattBuff[a + 3];
tmp = pattBuff[a + 2] & 0x0F;
if (tmp == 1)
{
ton->effTyp = 15;
if (h_STM.verMinor < 21)
ton->eff = ((ton->eff / 10) << 4) + (ton->eff % 10);
ton->eff >>= 4;
}
else if (tmp == 3)
{
ton->effTyp = 13;
ton->eff = 0;
}
else if (tmp == 2 || (tmp >= 4 && tmp <= 12))
{
ton->effTyp = stmEff[tmp];
if (ton->effTyp == 0xA)
{
if (ton->eff & 0x0F)
ton->eff &= 0x0F;
else
ton->eff &= 0xF0;
}
}
else
{
ton->eff = 0;
}
a += 4;
}
}
if (tmpPatternEmpty(i))
{
if (pattTmp[i] != NULL)
{
free(pattTmp[i]);
pattTmp[i] = NULL;
}
}
}
for (i = 0; i < 31; i++)
{
memcpy(&songTmp.instrName[1+i], h_STM.instr[i].name, 12);
if (h_STM.instr[i].len != 0 && h_STM.instr[i].reserved1 != 0)
{
allocateTmpInstr(1 + i);
setNoEnvelope(instrTmp[i]);
s = &instrTmp[1+i]->samp[0];
if (!allocateTmpSmpData(s, h_STM.instr[i].len))
{
loaderMsgBox("Not enough memory!");
return false;
}
s->len = h_STM.instr[i].len;
s->vol = h_STM.instr[i].vol;
s->repS = h_STM.instr[i].repS;
s->repL = h_STM.instr[i].repE - h_STM.instr[i].repS;
memcpy(s->name, h_STM.instr[i].name, 12);
tuneSample(s, h_STM.instr[i].rate, tmpLinearPeriodsFlag);
if (s->repS < s->len && h_STM.instr[i].repE > s->repS && h_STM.instr[i].repE != 0xFFFF)
{
if (s->repS+s->repL > s->len)
s->repL = s->len - s->repS;
s->typ = 1; // enable loop
}
else
{
s->repS = 0;
s->repL = 0;
s->typ = 0;
}
if (s->vol > 64)
s->vol = 64;
if (fread(s->pek, s->len, 1, f) != 1)
{
loaderMsgBox("General I/O error during loading! Possibly corrupt module?");
return false;
}
}
}
return true;
}
static uint8_t stmTempoToBPM(uint8_t tempo) // ported from original ST2.3 replayer code
{
const uint8_t slowdowns[16] = { 140, 50, 25, 15, 10, 7, 6, 4, 3, 3, 2, 2, 2, 2, 1, 1 };
uint16_t hz = 50;
hz -= ((slowdowns[tempo >> 4] * (tempo & 15)) >> 4); // can and will underflow
const uint32_t bpm = (hz << 1) + (hz >> 1); // BPM = hz * 2.5
return (uint8_t)CLAMP(bpm, 32, 255); // result can be slightly off, but close enough...
}