streamlined various functions

This commit is contained in:
Christian Kroll 2010-12-14 23:00:21 +00:00
parent 8c92d54ff6
commit 14d8dc969a
1 changed files with 90 additions and 79 deletions

View File

@ -217,22 +217,44 @@ uint8_t tetris_bucket_collision(tetris_bucket_t *pBucket,
nBucketPart |= 0xFFFF << ((pBucket->nHeight - nRow) * 4); nBucketPart |= 0xFFFF << ((pBucket->nHeight - nRow) * 4);
} }
int8_t const nStop = (nRow + 3) < pBucket->nHeight ? // return if the piece already collides with the border
nRow + 3 : pBucket->nHeight - 1; if (nPieceMap & nBucketPart)
// mask those blocks which are not covered by the piece
uint16_t nDumpMask = nColumn >= 0 ? 0x000F << nColumn : 0x000F >> -nColumn;
// value for shifting blocks to the corresponding part of the piece
int8_t nShift = -nColumn + (nRow < 0 ? 4 * -nRow : 0);
for (int8_t y = nRow >= 0 ? nRow : 0; y <= nStop; ++y)
{
uint16_t nTemp = pBucket->dump[y] & nDumpMask;
nBucketPart |= nShift >= 0 ? nTemp << nShift : nTemp >> -nShift;
if ((nPieceMap & nBucketPart) != 0)
{ {
// collision // collision
return 1; return 1;
} }
nShift += 4;
// range for inspecting the piece row by row (starting at the bottom)
int8_t nStart = nRow;
// skip empty rows at the bottom at the piece
if (nPieceMap > 0x0FFF)
{
nStart += 3; // piece spans over 4 rows
}
else if (nPieceMap > 0x00FF)
{
nStart += 2; // last row of the piece is empty
}
else if (nPieceMap > 0x000F)
{
nStart += 1; // last two rows of the piece are empty
}
int8_t const nStop = nRow >= 0 ? nRow : 0;
// mask those blocks which are not covered by the piece
uint16_t nDumpMask = nColumn >= 0 ? 0x000F << nColumn : 0x000F >> -nColumn;
// value for shifting blocks to the corresponding part of the piece
int8_t nShift = 12 - nColumn - 4 * (nRow + 3 - nStart);
// compare piece with dump
for (int8_t y = nStart; y >= nStop; --y)
{
uint16_t nTemp = pBucket->dump[y] & nDumpMask;
nBucketPart |= nShift >= 0 ? nTemp << nShift : nTemp >> -nShift;
if (nPieceMap & nBucketPart)
{
// collision
return 1;
}
nShift -= 4;
} }
// if we reach here, no collision was detected // if we reach here, no collision was detected
@ -243,59 +265,51 @@ uint8_t tetris_bucket_collision(tetris_bucket_t *pBucket,
void tetris_bucket_advancePiece(tetris_bucket_t *pBucket) void tetris_bucket_advancePiece(tetris_bucket_t *pBucket)
{ {
assert(pBucket != NULL); assert(pBucket != NULL);
// a piece can only be lowered if it is hovering or gliding // a piece can only be lowered if it is hovering or gliding
assert ((pBucket->status == TETRIS_BUS_HOVERING) || assert ((pBucket->status == TETRIS_BUS_HOVERING) ||
(pBucket->status == TETRIS_BUS_GLIDING)); (pBucket->status == TETRIS_BUS_GLIDING));
// collision detected? check if we can embed the piece into the bucket...
if (tetris_bucket_collision(pBucket, pBucket->nColumn, pBucket->nRow + 1)) if (tetris_bucket_collision(pBucket, pBucket->nColumn, pBucket->nRow + 1))
{ {
uint16_t nPiece = tetris_piece_getBitmap(pBucket->pPiece); uint16_t nPieceMap = tetris_piece_getBitmap(pBucket->pPiece);
// determine first row of the piece (skipping empty lines at the top)
int8_t nPieceTop = pBucket->nRow;
if (!(nPieceMap & 0x0FFF))
{
nPieceTop += 3;
}
else if (!(nPieceMap & 0x00FF))
{
nPieceTop += 2;
}
else if (!(nPieceMap & 0x000F))
{
nPieceTop += 1;
}
// Is the bucket filled up? // Is the bucket filled up?
if ((pBucket->nRow < 0) && if (nPieceTop < 0)
(nPiece & (0x0FFF >> ((3 + pBucket->nRow) << 2))) != 0)
{ {
pBucket->status = TETRIS_BUS_GAMEOVER; pBucket->status = TETRIS_BUS_GAMEOVER;
} }
else else
{ {
// determine valid start point for dump index // update value for the first tainted row
int8_t nStartRow = ((pBucket->nRow + 3) < pBucket->nHeight) ? pBucket->nFirstTaintedRow = pBucket->nFirstTaintedRow > nPieceTop ?
(pBucket->nRow + 3) : pBucket->nHeight - 1; nPieceTop : pBucket->nFirstTaintedRow;
for (int8_t i = nStartRow; i >= pBucket->nRow; --i)
{
int8_t y = i - pBucket->nRow;
// clear all bits of the piece we are not interested in and // embed piece into the dump
// align the rest to LSB int8_t nStopRow = (pBucket->nRow + 3) >= pBucket->nHeight ?
uint16_t nPieceMap = (nPiece & (0x000F << (y << 2))) >> (y << 2); pBucket->nHeight - 1 : pBucket->nRow + 3;
// shift the remaining content to the current column nPieceMap >>= (nPieceTop - pBucket->nRow) * 4;
if (pBucket->nColumn >= 0) while (nPieceTop <= nStopRow)
{ {
nPieceMap <<= pBucket->nColumn; uint16_t nTemp = nPieceMap & 0x000F;
pBucket->dump[nPieceTop++] ^= pBucket->nColumn >= 0 ?
nTemp << pBucket->nColumn : nTemp >> -pBucket->nColumn;
nPieceMap >>= 4;
} }
else
{
nPieceMap >>= -pBucket->nColumn;
}
// embed piece in bucket
pBucket->dump[i] |= nPieceMap;
}
// update value for the highest row with matter
int8_t nPieceRow = pBucket->nRow;
uint16_t nMask = 0x000F;
for (int i = 0; i < 4; ++i, nMask <<= 4)
{
if ((nMask & nPiece) != 0)
{
nPieceRow += i;
break;
}
}
pBucket->nFirstTaintedRow = (pBucket->nFirstTaintedRow > nPieceRow) ?
nPieceRow : pBucket->nFirstTaintedRow;
// the piece has finally been docked // the piece has finally been docked
pBucket->status = TETRIS_BUS_DOCKED; pBucket->status = TETRIS_BUS_DOCKED;
@ -303,10 +317,8 @@ void tetris_bucket_advancePiece(tetris_bucket_t *pBucket)
} }
else else
{ {
// since there is no collision the piece may continue its travel // no collision: piece may continue its travel to the ground...
// to the ground...
pBucket->nRow++; pBucket->nRow++;
// are we gliding? // are we gliding?
pBucket->status = tetris_bucket_hoverStatus(pBucket); pBucket->status = tetris_bucket_hoverStatus(pBucket);
} }
@ -342,7 +354,7 @@ uint8_t tetris_bucket_rotatePiece(tetris_bucket_t *pBucket,
{ {
assert(pBucket != NULL); assert(pBucket != NULL);
// a piece can only be rotation if it is still hovering or gliding // a piece can only be rotated if it is still hovering or gliding
assert((pBucket->status == TETRIS_BUS_HOVERING) || assert((pBucket->status == TETRIS_BUS_HOVERING) ||
(pBucket->status == TETRIS_BUS_GLIDING)); (pBucket->status == TETRIS_BUS_GLIDING));
@ -352,21 +364,13 @@ uint8_t tetris_bucket_rotatePiece(tetris_bucket_t *pBucket,
if (tetris_bucket_collision(pBucket, pBucket->nColumn, pBucket->nRow) != 0) if (tetris_bucket_collision(pBucket, pBucket->nColumn, pBucket->nRow) != 0)
{ {
// in that case we revert the rotation // in that case we revert the rotation
if (rotation == TETRIS_PC_ROT_CW) tetris_piece_rotate(pBucket->pPiece, rotation == TETRIS_PC_ROT_CW ?
{ TETRIS_PC_ROT_CCW : TETRIS_PC_ROT_CW);
tetris_piece_rotate(pBucket->pPiece, TETRIS_PC_ROT_CCW);
}
else
{
tetris_piece_rotate(pBucket->pPiece, TETRIS_PC_ROT_CW);
}
return 0; return 0;
} }
// are we gliding? // are we gliding?
pBucket->status = tetris_bucket_hoverStatus(pBucket); pBucket->status = tetris_bucket_hoverStatus(pBucket);
return 1; return 1;
} }
@ -444,40 +448,39 @@ int8_t tetris_bucket_predictDeepestRow(tetris_bucket_t *pBucket,
tetris_piece_t *pActualPiece = pBucket->pPiece; tetris_piece_t *pActualPiece = pBucket->pPiece;
pBucket->pPiece = pPiece; pBucket->pPiece = pPiece;
// determine empty rows of the bottom of piece which may overlap the dump // skip empty rows at the bottom of the piece which may overlap the dump
uint16_t nMap = tetris_piece_getBitmap(pPiece); uint16_t nMap = tetris_piece_getBitmap(pPiece);
int8_t nOffset = 0; if (nMap > 0x0FFF)
if ((nMap & 0xF000) != 0) {
nOffset = 3; nStartingRow -= 3; // piece spans over 4 rows
else if ((nMap & 0xFF00) != 0) }
nOffset = 2; else if (nMap > 0x00FF)
else if ((nMap & 0xFFF0) != 0) {
nOffset = 1; nStartingRow -= 2; // last row of the piece is empty
int8_t nRow = nStartingRow - nOffset; }
else if (nMap > 0x000F)
{
nStartingRow -= 1; // last two rows of the piece are empty
}
// check if the piece collides with the left or the right wall // check if the piece collides with one of the side borders
if ((nRow < -3) || (((nColumn < 0) || (nColumn >= pBucket->nWidth - 3)) && if (nStartingRow >= -3)
tetris_bucket_collision(pBucket, nColumn, nRow)))
{ {
nRow = TETRIS_BUCKET_INVALIDROW; while (!tetris_bucket_collision(pBucket, nColumn, nStartingRow + 1))
{
++nStartingRow;
} }
// determine deepest row // bucket overflow?
else if (nStartingRow < 0 && ((0xFFFF >> (((4 + nStartingRow) * 4))) & nMap))
{ {
while (!tetris_bucket_collision(pBucket, nColumn, nRow + 1)) nStartingRow = TETRIS_BUCKET_INVALIDROW;
{
++nRow;
}
if ((nRow < 0) && (((nRow + 4) * 4) << nMap))
{
nRow = TETRIS_BUCKET_INVALIDROW;
} }
} }
// restore actual bucket piece // restore actual bucket piece
pBucket->pPiece = pActualPiece; pBucket->pPiece = pActualPiece;
return nRow; return nStartingRow;
} }
@ -524,6 +527,12 @@ uint16_t* tetris_bucket_predictBottomRow(tetris_bucket_iterator_t *pIt,
int8_t nRow, int8_t nRow,
int8_t nColumn) int8_t nColumn)
{ {
assert(pIt != NULL);
assert(pBucket != NULL);
assert(pPiece != NULL);
assert(nRow > -4 && nRow < pBucket->nHeight);
assert(nColumn > -4 && nColumn < pBucket->nWidth);
pIt->pBucket = pBucket; pIt->pBucket = pBucket;
pIt->nCurrentRow = pBucket->nHeight - 1; pIt->nCurrentRow = pBucket->nHeight - 1;
pIt->nRowBuffer = 0; pIt->nRowBuffer = 0;
@ -552,6 +561,8 @@ uint16_t* tetris_bucket_predictBottomRow(tetris_bucket_iterator_t *pIt,
uint16_t* tetris_bucket_predictNextRow(tetris_bucket_iterator_t *pIt) uint16_t* tetris_bucket_predictNextRow(tetris_bucket_iterator_t *pIt)
{ {
assert(pIt != NULL);
if ((pIt->nPieceHighestRow > -4) && (pIt->nCurrentRow >= pIt->nStopRow)) if ((pIt->nPieceHighestRow > -4) && (pIt->nCurrentRow >= pIt->nStopRow))
{ {
uint16_t nTemp = 0; uint16_t nTemp = 0;