ref: 7d5a28fd902385d1517de4ae47f73a8150dd02e3
dir: /src/blitter.cpp/
// blitter.c #include "stdafx.h" #include "SDLU.h" #include "main.h" #include "gworld.h" #include "blitter.h" #include "font.h" #include "level.h" #include "graphics.h" MBoolean update[2][kGridAcross][kGridDown]; MBoolean refresh[2]; void InitBlitter( void ) { int player, x, y; for( player=0; player<=1; player++ ) { refresh[player] = false; for( x=0; x<kGridAcross; x++ ) { for( y=0; y<kGridDown; y++ ) { update[player][x][y] = false; } } } } void UpdatePlayerWindow( int player ) { SDL_Rect fullSDLRect, offsetSDLRect; int x, y; if( control[player] == kNobodyControl ) return; if( playerWindowVisible[player] && refresh[player] ) { MRect updateRect = {0, 0, 0, 0}, fullRect, offsetRect; MBoolean first = true; for( x=0; x<kGridAcross; x++ ) { for( y=1; y<kGridDown; y++ ) { if( update[player][x][y] ) { updateRect.top = y * kBlobVertSize; updateRect.left = x * kBlobHorizSize; updateRect.bottom = updateRect.top + kBlobVertSize; updateRect.right = updateRect.left + kBlobHorizSize; if( first ) { fullRect = updateRect; first = false; } else { UnionMRect( &fullRect, &updateRect, &fullRect ); } update[player][x][y] = false; } } } if( !first ) { offsetRect = fullRect; OffsetMRect( &offsetRect, playerWindowRect[player].left, playerWindowRect[player].top - kBlobVertSize ); SDLU_BlitFrontSurface( playerSpriteSurface[player], SDLU_MRectToSDLRect( &fullRect, &fullSDLRect ), SDLU_MRectToSDLRect( &offsetRect, &offsetSDLRect ) ); } } } void SetUpdateRect( int player, MRect *where ) { int x,y; int xMin, xMax, yMin, yMax; xMin = where->left / kBlobHorizSize; xMax = ( where->right + kBlobHorizSize - 1 ) / kBlobHorizSize; if( xMin < 0 ) xMin = 0; if( xMin > (kGridAcross-1) ) xMin = kGridAcross-1; if( xMax < 0 ) xMax = 0; if( xMax > kGridAcross ) xMax = kGridAcross; yMin = where->top / kBlobVertSize; yMax = ( where->bottom + kBlobVertSize - 1 ) / kBlobVertSize; if( yMin < 0 ) yMin = 0; if( yMin > (kGridDown-1) ) yMin = kGridDown-1; if( yMax < 0 ) yMax = 0; if( yMax > kGridDown ) yMax = kGridDown; for( x=xMin; x<xMax; x++ ) { for( y=yMin; y<yMax; y++ ) { update[player][x][y] = true; } } refresh[player] = true; } void SurfaceBlitMask( SDL_Surface* object, SDL_Surface* mask, SDL_Surface* dest, const MRect* objectRect, const MRect* maskRect, const MRect* destRect ) { int startX = 0, startY = 0, endX, endY, x, y, srcRowBytes, mskRowBytes, dstRowBytes; unsigned char *src, *msk, *dst; MRect destBounds; SDLU_SDLRectToMRect( &dest->clip_rect, &destBounds ); endX = objectRect->right - objectRect->left; endY = objectRect->bottom - objectRect->top; if( destRect->left > destBounds.right || // completely clipped? destRect->right < destBounds.left || destRect->top > destBounds.bottom || destRect->bottom < destBounds.top ) { return; // do nothing } src = (unsigned char*) object->pixels; msk = (unsigned char*) mask->pixels; dst = (unsigned char*) dest->pixels; srcRowBytes = object->pitch; mskRowBytes = mask->pitch; dstRowBytes = dest->pitch; src += (objectRect->top * srcRowBytes) + (objectRect->left * BYTES_PER_PIXEL); msk += (maskRect->top * mskRowBytes) + (maskRect->left * BYTES_PER_MASK_PIXEL); dst += (destRect->top * dstRowBytes) + (destRect->left * BYTES_PER_PIXEL); if( destRect->left < destBounds.left ) startX -= destRect->left - destBounds.left; if( destRect->right > destBounds.right ) endX -= destRect->right - destBounds.right; if( destRect->top < destBounds.top ) startY -= destRect->top - destBounds.top; if( destRect->bottom > destBounds.bottom ) endY -= destRect->bottom - destBounds.bottom; msk += (mskRowBytes * startY) + (startX * BYTES_PER_MASK_PIXEL); src += (srcRowBytes * startY) + (startX * BYTES_PER_PIXEL); dst += (dstRowBytes * startY) + (startX * BYTES_PER_PIXEL); for( y=startY; y<endY; y++ ) { unsigned char *tSrc = src, *tDst = dst, *tMsk = msk; for( x=startX; x<endX; x++ ) { if( *msk ) { *(COLOR_T*)dst = *(COLOR_T*)src; } src += BYTES_PER_PIXEL; dst += BYTES_PER_PIXEL; msk += BYTES_PER_MASK_PIXEL; } src = tSrc + srcRowBytes; dst = tDst + dstRowBytes; msk = tMsk + mskRowBytes; } } void SurfaceBlitBlob( const MRect* blobRect, const MRect* destRect ) { SurfaceBlitMask( blobSurface, maskSurface, SDLU_GetCurrentSurface(), blobRect, blobRect, destRect ); } void SurfaceBlitColor( SDL_Surface* mask, SDL_Surface* dest, const MRect* maskRect, const MRect* destRect, int r, int g, int b, int weight ) { int startX = 0, startY = 0, endX, endY, x, y, mskRowBytes, dstRowBytes; unsigned char *msk, *dst; MRect destBounds; endX = maskRect->right - maskRect->left; endY = maskRect->bottom - maskRect->top; SDLU_SDLRectToMRect( &dest->clip_rect, &destBounds ); if( destRect->left > destBounds.right || // completely clipped? destRect->right < destBounds.left || destRect->top > destBounds.bottom || destRect->bottom < destBounds.top ) { return; // do nothing } msk = (unsigned char*) mask->pixels; dst = (unsigned char*) dest->pixels; mskRowBytes = mask->pitch; dstRowBytes = dest->pitch; msk += (maskRect->top * mskRowBytes) + (maskRect->left * BYTES_PER_MASK_PIXEL); dst += (destRect->top * dstRowBytes) + (destRect->left * BYTES_PER_PIXEL); if( destRect->left < destBounds.left ) startX -= destRect->left - destBounds.left; if( destRect->right > destBounds.right ) endX -= destRect->right - destBounds.right; if( destRect->top < destBounds.top ) startY -= destRect->top - destBounds.top; if( destRect->bottom > destBounds.bottom ) endY -= destRect->bottom - destBounds.bottom; msk += (mskRowBytes * startY) + (startX * BYTES_PER_MASK_PIXEL); dst += (dstRowBytes * startY) + (startX * BYTES_PER_PIXEL); r *= weight; g *= weight; b *= weight; weight = FULL_WEIGHT - weight; for( y=startY; y<endY; y++ ) { unsigned char *tMsk = msk, *tDst = dst; int work, workB, workG, workR; for( x=startX; x<endX; x++ ) { if( *msk ) { work = *(COLOR_T*)dst; workB = ((((work ) & CHANNEL_MASK)*weight) + b) >> BITS_PER_1CHANNEL; workG = ((((work>>BITS_PER_1CHANNEL ) & CHANNEL_MASK)*weight) + g) ; workR = ((((work>>BITS_PER_2CHANNELS) & CHANNEL_MASK)*weight) + r) << BITS_PER_1CHANNEL; *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); } dst += BYTES_PER_PIXEL; msk += BYTES_PER_MASK_PIXEL; } msk = tMsk + mskRowBytes; dst = tDst + dstRowBytes; } } void SurfaceBlitAlpha( SDL_Surface* back, SDL_Surface* source, SDL_Surface* alpha, SDL_Surface* dest, const MRect* backRect, const MRect* sourceRect, const MRect* alphaRect, const MRect* destRect ) { int startX = 0, startY = 0, endX, endY, x, y, srcRowBytes, alfRowBytes, dstRowBytes, bckRowBytes; unsigned char *bck, *src, *alf, *dst; MRect destBounds; endX = sourceRect->right - sourceRect->left; endY = sourceRect->bottom - sourceRect->top; SDLU_SDLRectToMRect( &dest->clip_rect, &destBounds ); if( destRect->left > destBounds.right || // completely clipped? destRect->right < destBounds.left || destRect->top > destBounds.bottom || destRect->bottom < destBounds.top ) { return; // do nothing } bck = (unsigned char*) back->pixels; src = (unsigned char*) source->pixels; alf = (unsigned char*) alpha->pixels; dst = (unsigned char*) dest->pixels; bckRowBytes = back->pitch; srcRowBytes = source->pitch; alfRowBytes = alpha->pitch; dstRowBytes = dest->pitch; bck += (backRect->top * bckRowBytes) + (backRect->left * BYTES_PER_PIXEL); src += (sourceRect->top * srcRowBytes) + (sourceRect->left * BYTES_PER_PIXEL); alf += (alphaRect->top * alfRowBytes) + (alphaRect->left * BYTES_PER_PIXEL); dst += (destRect->top * dstRowBytes) + (destRect->left * BYTES_PER_PIXEL); if( destRect->left < destBounds.left ) startX -= destRect->left - destBounds.left; if( destRect->right > destBounds.right ) endX -= destRect->right - destBounds.right; if( destRect->top < destBounds.top ) startY -= destRect->top - destBounds.top; if( destRect->bottom > destBounds.bottom ) endY -= destRect->bottom - destBounds.bottom; bck += (bckRowBytes * startY) + (startX * BYTES_PER_PIXEL); src += (srcRowBytes * startY) + (startX * BYTES_PER_PIXEL); alf += (alfRowBytes * startY) + (startX * BYTES_PER_PIXEL); dst += (dstRowBytes * startY) + (startX * BYTES_PER_PIXEL); for( y=startY; y<endY; y++ ) { unsigned char *tSrc = src, *tAlf = alf, *tDst = dst, *tBck = bck; int pixS, pixB, weightS, weightB, workB, workG, workR; for( x=startX; x<endX; x++ ) { weightB = *(COLOR_T*)alf; if( (weightB & (RED_MASK | GREEN_MASK | BLUE_MASK)) == (RED_MASK | GREEN_MASK | BLUE_MASK)) { *(COLOR_T*)dst = *(COLOR_T*)bck; } else if( (weightB & (RED_MASK | GREEN_MASK | BLUE_MASK)) == 0) { *(COLOR_T*)dst = *(COLOR_T*)src; } else { weightS = ~weightB; pixS = *(COLOR_T*)src; pixB = *(COLOR_T*)bck; workB = ((((pixS ) & CHANNEL_MASK) * ((weightS ) & CHANNEL_MASK)) + (((pixB ) & CHANNEL_MASK) * ((weightB ) & CHANNEL_MASK))) >> BITS_PER_1CHANNEL; workG = ((((pixS >> BITS_PER_1CHANNEL ) & CHANNEL_MASK) * ((weightS >> BITS_PER_1CHANNEL ) & CHANNEL_MASK)) + (((pixB >> BITS_PER_1CHANNEL ) & CHANNEL_MASK) * ((weightB >> BITS_PER_1CHANNEL ) & CHANNEL_MASK))); workR = ((((pixS >> BITS_PER_2CHANNELS) & CHANNEL_MASK) * ((weightS >> BITS_PER_2CHANNELS) & CHANNEL_MASK)) + (((pixB >> BITS_PER_2CHANNELS) & CHANNEL_MASK) * ((weightB >> BITS_PER_2CHANNELS) & CHANNEL_MASK))) << BITS_PER_1CHANNEL; *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); } src += BYTES_PER_PIXEL; alf += BYTES_PER_PIXEL; bck += BYTES_PER_PIXEL; dst += BYTES_PER_PIXEL; } bck = tBck + bckRowBytes; src = tSrc + srcRowBytes; alf = tAlf + alfRowBytes; dst = tDst + dstRowBytes; } } void SurfaceBlitWeightedDualAlpha(SDL_Surface* back, SDL_Surface* source, SDL_Surface* mask, SDL_Surface* alpha, SDL_Surface* dest, const MRect* backRect, const MRect* sourceRect, const MRect* maskRect, const MRect* alphaRect, const MRect* destRect, int inWeight ) { int startX = 0, startY = 0, endX, endY, x, y, srcRowBytes, alfRowBytes, mskRowBytes, dstRowBytes, bckRowBytes; unsigned char *bck, *src, *alf, *msk, *dst; MRect destBounds; endX = sourceRect->right - sourceRect->left; endY = sourceRect->bottom - sourceRect->top; SDLU_SDLRectToMRect( &dest->clip_rect, &destBounds ); if( destRect->left > destBounds.right || // completely clipped? destRect->right < destBounds.left || destRect->top > destBounds.bottom || destRect->bottom < destBounds.top ) { return; // do nothing } bck = (unsigned char*) back->pixels; src = (unsigned char*) source->pixels; msk = (unsigned char*) mask->pixels; alf = (unsigned char*) alpha->pixels; dst = (unsigned char*) dest->pixels; bckRowBytes = back->pitch; srcRowBytes = source->pitch; mskRowBytes = mask->pitch; alfRowBytes = alpha->pitch; dstRowBytes = dest->pitch; bck += (backRect->top * bckRowBytes) + (backRect->left * BYTES_PER_PIXEL); src += (sourceRect->top * srcRowBytes) + (sourceRect->left * BYTES_PER_PIXEL); alf += (alphaRect->top * alfRowBytes) + (alphaRect->left * BYTES_PER_PIXEL); dst += (destRect->top * dstRowBytes) + (destRect->left * BYTES_PER_PIXEL); msk += (maskRect->top * mskRowBytes) + (maskRect->left * BYTES_PER_MASK_PIXEL); if( destRect->left < destBounds.left ) startX -= destRect->left - destBounds.left; if( destRect->right > destBounds.right ) endX -= destRect->right - destBounds.right; if( destRect->top < destBounds.top ) startY -= destRect->top - destBounds.top; if( destRect->bottom > destBounds.bottom ) endY -= destRect->bottom - destBounds.bottom; bck += (bckRowBytes * startY) + (startX * BYTES_PER_PIXEL); src += (srcRowBytes * startY) + (startX * BYTES_PER_PIXEL); alf += (alfRowBytes * startY) + (startX * BYTES_PER_PIXEL); dst += (dstRowBytes * startY) + (startX * BYTES_PER_PIXEL); msk += (mskRowBytes * startY) + (startX * BYTES_PER_MASK_PIXEL); for( y=startY; y<endY; y++ ) { unsigned char *tSrc = src, *tAlf = alf, *tDst = dst, *tBck = bck, *tMsk = msk; int pixS, pixB, weightS, weightB, work, workB, workG, workR; for( x=startX; x<endX; x++ ) { if( *msk ) { work = *(COLOR_T*)alf; workB = ((((work ) & CHANNEL_MASK)*inWeight) ) >> BITS_PER_1CHANNEL; workG = ((((work>>BITS_PER_1CHANNEL ) & CHANNEL_MASK)*inWeight) ); workR = ((((work>>BITS_PER_2CHANNELS) & CHANNEL_MASK)*inWeight) ) << BITS_PER_1CHANNEL; weightB = ~((workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK)); if( (weightB & (RED_MASK | GREEN_MASK | BLUE_MASK)) == (RED_MASK | GREEN_MASK | BLUE_MASK)) { *(COLOR_T*)dst = *(COLOR_T*)bck; } else if( (weightB & (RED_MASK | GREEN_MASK | BLUE_MASK)) == 0) { *(COLOR_T*)dst = *(COLOR_T*)src; } else { weightS = ~weightB; pixS = *(COLOR_T*)src; pixB = *(COLOR_T*)bck; workB = ((((pixS ) & CHANNEL_MASK) * ((weightS ) & CHANNEL_MASK)) + (((pixB ) & CHANNEL_MASK) * ((weightB ) & CHANNEL_MASK))) >> BITS_PER_1CHANNEL; workG = ((((pixS >> BITS_PER_1CHANNEL ) & CHANNEL_MASK) * ((weightS >> BITS_PER_1CHANNEL ) & CHANNEL_MASK)) + (((pixB >> BITS_PER_1CHANNEL ) & CHANNEL_MASK) * ((weightB >> BITS_PER_1CHANNEL ) & CHANNEL_MASK))); workR = ((((pixS >> BITS_PER_2CHANNELS) & CHANNEL_MASK) * ((weightS >> BITS_PER_2CHANNELS) & CHANNEL_MASK)) + (((pixB >> BITS_PER_2CHANNELS) & CHANNEL_MASK) * ((weightB >> BITS_PER_2CHANNELS) & CHANNEL_MASK))) << BITS_PER_1CHANNEL; *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); } } src += BYTES_PER_PIXEL; alf += BYTES_PER_PIXEL; bck += BYTES_PER_PIXEL; dst += BYTES_PER_PIXEL; msk += BYTES_PER_MASK_PIXEL; } bck = tBck + bckRowBytes; src = tSrc + srcRowBytes; alf = tAlf + alfRowBytes; dst = tDst + dstRowBytes; msk = tMsk + mskRowBytes; } } void SurfaceBlitWeightedCharacter( SkittlesFontPtr font, unsigned char text, MPoint *dPoint, int r, int g, int b, int alpha ) { if (alpha == FULL_WEIGHT) { SurfaceBlitCharacter( font, text, dPoint, r, g, b, 0 ); return; } if (alpha == 0) { return; } SDL_Surface* destSurface; unsigned char* src; unsigned char* dst; int srcRowBytes; int dstRowBytes; int index; MRect destBounds; int height = font->surface->h; int width = font->width[text]; int across = font->across[text]; destSurface = SDLU_GetCurrentSurface(); SDLU_SDLRectToMRect( &destSurface->clip_rect, &destBounds ); if( (dPoint->h + width) > destBounds.right || // clipped? (dPoint->v + height) > destBounds.bottom || dPoint->h < destBounds.left || dPoint->v < destBounds.top ) { dPoint->h += width; return; // do nothing } srcRowBytes = font->surface->pitch; dstRowBytes = destSurface->pitch; src = (unsigned char*) font->surface->pixels + across; dst = (unsigned char*) destSurface->pixels + (dPoint->h * BYTES_PER_PIXEL) + (dPoint->v * dstRowBytes); while( height-- ) { unsigned char *tSrc = src, *tDst = dst; for( index=0; index<width; index++ ) { int workR, workG, workB, work, weightS, weightD; weightS = *src & CHANNEL_MASK; weightS = (weightS * alpha) >> BITS_PER_1CHANNEL; if( weightS ) { weightD = FULL_WEIGHT - weightS; work = *(COLOR_T*)dst; workB = ((((work ) & CHANNEL_MASK) * weightD) + (b * weightS)) >> BITS_PER_1CHANNEL; workG = ((((work>>BITS_PER_1CHANNEL ) & CHANNEL_MASK) * weightD) + (g * weightS)); workR = ((((work>>BITS_PER_2CHANNELS) & CHANNEL_MASK) * weightD) + (r * weightS)) << BITS_PER_1CHANNEL; *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); } src++; dst+=BYTES_PER_PIXEL; } src = tSrc + srcRowBytes; dst = tDst + dstRowBytes; } dPoint->h += width; } void SurfaceBlitCharacter( SkittlesFontPtr font, unsigned char text, MPoint *dPoint, int r, int g, int b, int dropShadow ) { SDL_Surface* destSurface; unsigned char* src; unsigned char* dst; int srcRowBytes; int dstRowBytes; int index; int rgbPremixed; MRect destBounds; int height = font->surface->h; int width = font->width[text]; int across = font->across[text]; destSurface = SDLU_GetCurrentSurface(); SDLU_SDLRectToMRect( &destSurface->clip_rect, &destBounds ); if( (dPoint->h + width) > destBounds.right || // clipped? (dPoint->v + height) > destBounds.bottom || dPoint->h < destBounds.left || dPoint->v < destBounds.top ) { dPoint->h += width; return; // do nothing } srcRowBytes = font->surface->pitch; dstRowBytes = destSurface->pitch; src = (unsigned char*) font->surface->pixels + across; dst = (unsigned char*) destSurface->pixels + (dPoint->h * BYTES_PER_PIXEL) + (dPoint->v * dstRowBytes); rgbPremixed = (r << BITS_PER_2CHANNELS) | (g << BITS_PER_1CHANNEL) | b; switch( dropShadow ) { case 0: while( height-- ) { unsigned char *tSrc = src, *tDst = dst; for( index=0; index<width; index++ ) { int workR, workG, workB, work, weightS, weightD; weightS = *src & CHANNEL_MASK; if( weightS == CHANNEL_MASK ) { *(COLOR_T*)dst = rgbPremixed; } else if( weightS > 0 ) { weightD = FULL_WEIGHT - weightS; work = *(COLOR_T*)dst; workB = ((((work ) & CHANNEL_MASK) * weightD) + (b * weightS)) >> BITS_PER_1CHANNEL; workG = ((((work >> BITS_PER_1CHANNEL ) & CHANNEL_MASK) * weightD) + (g * weightS)); workR = ((((work >> BITS_PER_2CHANNELS) & CHANNEL_MASK) * weightD) + (r * weightS)) << BITS_PER_1CHANNEL; *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); } src++; dst+=BYTES_PER_PIXEL; } src = tSrc + srcRowBytes; dst = tDst + dstRowBytes; } break; default: { unsigned char *drp = dst + ((dstRowBytes + BYTES_PER_PIXEL) * dropShadow); while( height-- ) { unsigned char *tSrc = src, *tDst = dst, *tDrp = drp; for( index=0; index<width; index++ ) { int workR, workG, workB, work, weightS, weightD; weightS = *src & CHANNEL_MASK; if( weightS == CHANNEL_MASK ) { *(COLOR_T*)drp = 0; *(COLOR_T*)dst = rgbPremixed; } else if( weightS > 0 ) { weightD = FULL_WEIGHT - weightS; work = *(COLOR_T*)drp; workB = ((((work ) & CHANNEL_MASK) * weightD)) >> BITS_PER_1CHANNEL; workG = ((((work>>BITS_PER_1CHANNEL ) & CHANNEL_MASK) * weightD)); workR = ((((work>>BITS_PER_2CHANNELS) & CHANNEL_MASK) * weightD)) << BITS_PER_1CHANNEL; *(COLOR_T*)drp = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); work = *(COLOR_T*)dst; workB = ((((work ) & CHANNEL_MASK) * weightD) + (b * weightS)) >> BITS_PER_1CHANNEL; workG = ((((work>>BITS_PER_1CHANNEL ) & CHANNEL_MASK) * weightD) + (g * weightS)); workR = ((((work>>BITS_PER_2CHANNELS) & CHANNEL_MASK) * weightD) + (r * weightS)) << BITS_PER_1CHANNEL; *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); } src++; dst+=BYTES_PER_PIXEL; drp+=BYTES_PER_PIXEL; } src = tSrc + srcRowBytes; dst = tDst + dstRowBytes; drp = tDrp + dstRowBytes; } break; } } dPoint->h += width; } void SurfaceBlitColorOver( SDL_Surface* source, SDL_Surface* dest, const MRect* sourceRect, const MRect* destRect, int r, int g, int b, int weight ) { int startX = 0, startY = 0, endX, endY, x, y, dstRowBytes, srcRowBytes; unsigned char* src; unsigned char* dst; MRect destBounds; SDLU_SDLRectToMRect( &dest->clip_rect, &destBounds ); endX = destRect->right - destRect->left; endY = destRect->bottom - destRect->top; if( destRect->left > destBounds.right || // completely clipped? destRect->right < destBounds.left || destRect->top > destBounds.bottom || destRect->bottom < destBounds.top ) { return; // do nothing } src = (unsigned char*) source->pixels; dst = (unsigned char*) dest->pixels; srcRowBytes = source->pitch; dstRowBytes = dest->pitch; src += (sourceRect->top * srcRowBytes) + (sourceRect->left * BYTES_PER_PIXEL); dst += (destRect->top * dstRowBytes) + (destRect->left * BYTES_PER_PIXEL); if( destRect->left < destBounds.left ) startX -= destRect->left - destBounds.left; if( destRect->right > destBounds.right ) endX -= destRect->right - destBounds.right; if( destRect->top < destBounds.top ) startY -= destRect->top - destBounds.top; if( destRect->bottom > destBounds.bottom ) endY -= destRect->bottom - destBounds.bottom; src += (srcRowBytes * startY) + (startX * BYTES_PER_PIXEL); dst += (dstRowBytes * startY) + (startX * BYTES_PER_PIXEL); r *= weight; g *= weight; b *= weight; weight = FULL_WEIGHT - weight; for( y=startY; y<endY; y++ ) { unsigned char *tSrc = src, *tDst = dst; int work, workB, workG, workR; for( x=startX; x<endX; x++ ) { work = *(COLOR_T*)src; workB = ((((work ) & CHANNEL_MASK)*weight) + b) >> BITS_PER_1CHANNEL; workG = ((((work>>BITS_PER_1CHANNEL ) & CHANNEL_MASK)*weight) + g); workR = ((((work>>BITS_PER_2CHANNELS) & CHANNEL_MASK)*weight) + r) << BITS_PER_1CHANNEL; *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); src += BYTES_PER_PIXEL; dst += BYTES_PER_PIXEL; } src = tSrc + srcRowBytes; dst = tDst + dstRowBytes; } } // NOTE: due to rounding error, there should never be a case of transitioning all the way from 0 to 255. // You'll overflow and get weird glitches on the edges. void SurfaceBlitBlendOver(SDL_Surface* source, SDL_Surface* dest, const MRect* sourceRect, const MRect* destRect, int r1, int g1, int b1, int r2, int g2, int b2, int r3, int g3, int b3, int r4, int g4, int b4, int weight ) { int startX = 0, startY = 0, endX, endY, x, y; int rA, gA, bA; int rB, gB, bB; int rI, gI, bI; int vrLI, vgLI, vbLI; int vrRI, vgRI, vbRI; int weight12, ditherDiff; int width, height, dstRowBytes, srcRowBytes; unsigned char *src, *dst; MRect destBounds; MBoolean oddX = false; SDLU_SDLRectToMRect( &dest->clip_rect, &destBounds ); if( destRect->left > destBounds.right || // completely clipped? destRect->right < destBounds.left || destRect->top > destBounds.bottom || destRect->bottom < destBounds.top ) { return; // do nothing } endX = destRect->right - destRect->left; endY = destRect->bottom - destRect->top; src = (unsigned char*) source->pixels; dst = (unsigned char*) dest->pixels; srcRowBytes = source->pitch; dstRowBytes = dest->pitch; src += (sourceRect->top * srcRowBytes) + (sourceRect->left * BYTES_PER_PIXEL); dst += (destRect->top * dstRowBytes) + (destRect->left * BYTES_PER_PIXEL); if( destRect->left < destBounds.left ) startX -= destRect->left - destBounds.left; if( destRect->right > destBounds.right ) endX -= destRect->right - destBounds.right; if( destRect->top < destBounds.top ) startY -= destRect->top - destBounds.top; if( destRect->bottom > destBounds.bottom ) endY -= destRect->bottom - destBounds.bottom; src += (srcRowBytes * startY) + (startX * BYTES_PER_PIXEL); dst += (dstRowBytes * startY) + (startX * BYTES_PER_PIXEL); height = endY - startY; width = endX - startX; weight12 = weight << 12; r1 *= weight12; g1 *= weight12; b1 *= weight12; r2 *= weight12; g2 *= weight12; b2 *= weight12; r3 *= weight12; g3 *= weight12; b3 *= weight12; r4 *= weight12; g4 *= weight12; b4 *= weight12; ditherDiff = weight12 >> 1; vrLI = (r3 - r1) / height; vgLI = (g3 - g1) / height; vbLI = (b3 - b1) / height; vrRI = (r4 - r2) / height; vgRI = (g4 - g2) / height; vbRI = (b4 - b2) / height; weight = FULL_WEIGHT - weight; weight12 = weight << 12; if( (endX - startX) & 1 ) { endX--; oddX = true; } for( y=startY; y<endY; y++ ) { unsigned char *tSrc = src, *tDst = dst; int work, workB, workG, workR; if( y & 1 ) { rA = r1; gA = g1; bA = b1; rB = r1 - ditherDiff; if( rB < 0 ) rB = 0; gB = g1 - ditherDiff; if( gB < 0 ) gB = 0; bB = b1 - ditherDiff; if( bB < 0 ) bB = 0; } else { rA = r1 - ditherDiff; if( rA < 0 ) rA = 0; gA = g1 - ditherDiff; if( gA < 0 ) gA = 0; bA = b1 - ditherDiff; if( bA < 0 ) bA = 0; rB = r1; gB = g1; bB = b1; } rI = (2 * (r2 - r1)) / width; gI = (2 * (g2 - g1)) / width; bI = (2 * (b2 - b1)) / width; for( x=startX; x<endX; x+=2 ) { work = *(COLOR_T*)src; workB = ((((work ) & CHANNEL_MASK) * weight12) + bA) >> (12 + BITS_PER_1CHANNEL); workG = ((((work >> BITS_PER_1CHANNEL ) & CHANNEL_MASK) * weight12) + gA) >> (12 ); workR = ((((work >> BITS_PER_2CHANNELS) & CHANNEL_MASK) * weight12) + rA) >> (12 - BITS_PER_1CHANNEL); *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); src+= BYTES_PER_PIXEL; dst+= BYTES_PER_PIXEL; rA += rI; gA += gI; bA += bI; work = *(COLOR_T*)src; workB = ((((work ) & CHANNEL_MASK) * weight12) + bB) >> (12 + BITS_PER_1CHANNEL); workG = ((((work >> BITS_PER_1CHANNEL ) & CHANNEL_MASK) * weight12) + gB) >> (12 ); workR = ((((work >> BITS_PER_2CHANNELS) & CHANNEL_MASK) * weight12) + rB) >> (12 - BITS_PER_1CHANNEL); *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); src+= BYTES_PER_PIXEL; dst+= BYTES_PER_PIXEL; rB += rI; gB += gI; bB += bI; } if( oddX ) { work = *(COLOR_T*)src; workB = ((((work ) & CHANNEL_MASK) * weight12) + bA) >> (12 + BITS_PER_1CHANNEL); workG = ((((work >> BITS_PER_1CHANNEL ) & CHANNEL_MASK) * weight12) + gA) >> (12 ); workR = ((((work >> BITS_PER_2CHANNELS) & CHANNEL_MASK) * weight12) + rA) >> (12 - BITS_PER_1CHANNEL); *(COLOR_T*)dst = (workR & RED_MASK) | (workG & GREEN_MASK) | (workB & BLUE_MASK); } src = tSrc + srcRowBytes; dst = tDst + dstRowBytes; r1 += vrLI; r2 += vrRI; g1 += vgLI; g2 += vgRI; b1 += vbLI; b2 += vbRI; } }