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TINSEL: Some cleanup to the BMV code

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svn-id: r45397
This commit is contained in:
Max Horn 2009-10-26 10:39:51 +00:00
parent 88c7ca6f8f
commit a4c27cfe98
1 changed files with 82 additions and 53 deletions
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135
engines/tinsel/bmv.cpp
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@ -128,45 +128,44 @@ static const uint16 Au_DecTable[16] = {16512, 8256, 4128, 2064, 1032, 516, 258,
#define SCREEN_HIGH 429
#define SAM_P_BLOB (32 * 2)
#define ROR(x,v) x = ((x >> (v%32)) | (x << (32 - (v%32))));
#define ROL(x,v) x = ((x << (v%32)) | (x >> (32 - (v%32))));
#define NEXT_BYTE(v) v = forwardDirection ? v + 1 : v - 1;
#define ROR(x,v) x = ((x >> (v%32)) | (x << (32 - (v%32))))
#define ROL(x,v) x = ((x << (v%32)) | (x >> (32 - (v%32))))
#define NEXT_BYTE(v) v = (forwardDirection ? v + 1 : v - 1)
static void PrepBMV(byte *ScreenBeg, const byte *sourceData, int length, short deltaFetchDisp) {
uint8 NibbleHi = 0;
const byte *saved_esi;
uint32 eax = 0;
uint32 edx = length;
int32 ebx = deltaFetchDisp;
uint32 ecx = 0;
const byte *esi;
byte *edi, *ebp;
const byte *src;
byte *dst, *endDst;
bool forwardDirection = (deltaFetchDisp <= -SCREEN_WIDE) || (deltaFetchDisp >= 0);
const bool forwardDirection = (deltaFetchDisp <= -SCREEN_WIDE) || (deltaFetchDisp >= 0);
if (forwardDirection) {
// Forward decompression
esi = sourceData;
edi = ScreenBeg;
ebp = ScreenBeg + SCREEN_WIDE * SCREEN_HIGH;
src = sourceData;
dst = ScreenBeg;
endDst = ScreenBeg + SCREEN_WIDE * SCREEN_HIGH;
} else {
esi = sourceData + length - 1;
edi = ScreenBeg + SCREEN_WIDE * SCREEN_HIGH - 1;
ebp = ScreenBeg - 1;
src = sourceData + length - 1;
dst = ScreenBeg + SCREEN_WIDE * SCREEN_HIGH - 1;
endDst = ScreenBeg - 1;
}
bool firstLoop, flag;
int loopCtr = 0;
for (;;) {
do {
uint32 eax = 0;
uint32 bitshift = 0;
flag = false;
if ((loopCtr == 0) || (edx == 4)) {
// Get the next hi,lo nibble
eax = (eax & 0xffffff00) | *esi;
eax = (eax & 0xffffff00) | *src;
firstLoop = true;
} else {
// Get the high nibble
eax = (eax & 0xffffff00) | (NibbleHi >> 4);
eax = (eax & 0xffffff00) | NibbleHi;
firstLoop = false;
}
@ -177,8 +176,8 @@ static void PrepBMV(byte *ScreenBeg, const byte *sourceData, int length, short d
// Only execute this bit first the first time into the loop
if (!firstLoop) {
ROR(eax, 2);
ecx += 2;
eax = (eax & 0xffffff00) | *esi;
bitshift += 2;
eax = (eax & 0xffffff00) | *src;
if ((eax & 0xC) != 0)
break;
@ -187,14 +186,14 @@ static void PrepBMV(byte *ScreenBeg, const byte *sourceData, int length, short d
//@_rD2nd_1:
ROR(eax, 2); // Save bi-bit into hi 2 bits
ecx += 2; // and increase bit-shifter
bitshift += 2; // and increase bit-shifter
// Shift another 2 bits to get hi nibble
eax = (eax & 0xffffff00) | ((eax & 0xff) >> 2);
NEXT_BYTE(esi);
NEXT_BYTE(src);
if ((eax & 0xC) != 0) {
flag = true;
ROL(eax, ecx);
ROL(eax, bitshift);
break;
}
}
@ -207,20 +206,22 @@ static void PrepBMV(byte *ScreenBeg, const byte *sourceData, int length, short d
edx = 4; // offset rDNum_Lo ; Next nibble is a 'lo'
} else {
// @_rDNum_1
NibbleHi = (uint8)eax;
NibbleHi = ((uint8)eax) >> 4;
edx = 0; // offset rDNum_Hi ; Next nibble is a 'hi' (reserved)
eax &= 0xffffff0f;
NEXT_BYTE(esi);
ROL(eax, ecx);
NEXT_BYTE(src);
ROL(eax, bitshift);
}
//rDN_1:
//@_rD_or_R:
bool actionFlag = (eax & 1) != 0;
eax >>= 1;
ecx = eax - 1;
int byteLen = eax - 1;
// Move to next loop index
if (++loopCtr == 4) loopCtr = 1;
++loopCtr;
if (loopCtr == 4)
loopCtr = 1;
if (actionFlag) {
// Adjust loopCtr to fall into the correct processing case
@ -230,50 +231,78 @@ static void PrepBMV(byte *ScreenBeg, const byte *sourceData, int length, short d
switch (loopCtr) {
case 1:
// @_rDelta:
saved_esi = esi; // Save the source pointer
esi = edi + ebx; // Point it to existing data
#if 1
if (forwardDirection) {
memcpy(dst, dst + ebx, byteLen);
dst += byteLen;
} else {
dst -= byteLen;
memcpy(dst + 1, dst + ebx + 1, byteLen);
}
#else
const byte *saved_src = src; // Save the source pointer
src = dst + ebx; // Point it to existing data
while (ecx > 0) {
*edi = *esi;
NEXT_BYTE(esi);
NEXT_BYTE(edi);
--ecx;
while (byteLen > 0) {
*dst = *src;
NEXT_BYTE(src);
NEXT_BYTE(dst);
--byteLen;
}
esi = saved_esi;
src = saved_src;
#endif
break;
case 2:
// @_rRaw
// Copy data from source to dest
while (ecx > 0) {
*edi = *esi;
NEXT_BYTE(esi);
NEXT_BYTE(edi);
--ecx;
#if 1
if (forwardDirection) {
memcpy(dst, src, byteLen);
dst += byteLen;
src += byteLen;
} else {
dst -= byteLen;
src -= byteLen;
memcpy(dst + 1, src + 1, byteLen);
}
#else
while (byteLen > 0) {
*dst = *src;
NEXT_BYTE(src);
NEXT_BYTE(dst);
--byteLen;
}
#endif
break;
case 3:
// @_rRun
// Repeating run of data
eax = forwardDirection ? *(edi - 1) : *(edi + 1);
while (ecx > 0) {
*edi = (uint8)eax;
NEXT_BYTE(edi);
--ecx;
#if 1
if (forwardDirection) {
memset(dst, *(dst - 1), byteLen);
dst += byteLen;
} else {
eax = *(dst + 1);
dst -= byteLen;
memset(dst + 1, eax, byteLen);
}
#else
eax = forwardDirection ? *(dst - 1) : *(dst + 1);
while (byteLen > 0) {
*dst = (uint8)eax;
NEXT_BYTE(dst);
--byteLen;
}
#endif
break;
default:
break;
}
if (edi == ebp)
break; // Exit if complete
eax = 0;
}
} while (dst != endDst);
}
void BMVPlayer::InitBMV(byte *memoryBuffer) {