Subject: SDL_gfx modifications (modified files included)
From: "Sergio Padrino"
Date: Sun, 7 Sep 2008 14:34:38 +0200
To: aschiffler@ferzkopp.net

Hi!

First of all, thank you for your library, it's really useful ;)

I've had some problems with rotozoom and alpha (from SDL, not from SDL_gfx) features related with "color keying". I've modified SDL_rotozoomSurfaceXY to draw always the color key in the destination surface, so the same color key could be set when the transformation has finished.

At lines 911 and 916 you can see I first deactivate colorkey from the original surface so it's drawn in the converted surface. At lines 979, 981, 1057 and 1059 I just fill the whole destination surface with the color key, so when the original surface has been rotated, the remaining surface will have the colorkey and it will be transparent.

Now it works perfectly, but I haven't modified every function from the rotozoom library (because I haven't studied the whole code) but if you like this modification I think you can implement it easily :)

The other change is in the Makefile for MinGW compiler. Now SDL_gfxBlitFunc.o is included as an objective, and all paths are specified by the correspondant variables (include_dir, lib_dir...).

Again thank you for your work :)

Bye!

PS: I'm sorry about my bad English, I'm Spanish :S



/* SDL_rotozoom.c - rotozoomer for 32bit or 8bit surfaces LGPL (c) A. Schiffler */ #ifdef WIN32 #include <windows.h> #endif #include <stdlib.h> #include <string.h> #include "SDL_rotozoom.h" #define MAX(a,b) (((a) > (b)) ? (a) : (b)) /* 32bit integer-factor averaging Shrinker Shrinks 32bit RGBA/ABGR 'src' surface to 'dst' surface. */ int shrinkSurfaceRGBA(SDL_Surface * src, SDL_Surface * dst, int factorx, int factory) { int x, y, dx, dy, sgap, dgap, ra, ga, ba, aa; int n_average; tColorRGBA *sp, *osp, *oosp; tColorRGBA *dp; /* * Averaging integer shrink */ /* Precalculate division factor */ n_average = factorx*factory; /* * Scan destination */ sp = (tColorRGBA *) src->pixels; sgap = src->pitch - src->w * 4; dp = (tColorRGBA *) dst->pixels; dgap = dst->pitch - dst->w * 4; for (y = 0; y < dst->h; y++) { osp=sp; for (x = 0; x < dst->w; x++) { /* Trace out source box and accumulate */ oosp=sp; ra=ga=ba=aa=0; for (dy=0; dy < factory; dy++) { for (dx=0; dx < factorx; dx++) { ra += sp->r; ga += sp->g; ba += sp->b; aa += sp->a; sp++; } // src dx loop sp = (tColorRGBA *)((Uint8*)sp + (src->pitch - 4*factorx)); // next y } // src dy loop // next box-x sp = (tColorRGBA *)((Uint8*)oosp + 4*factorx); /* Store result in destination */ dp->r = ra/n_average; dp->g = ga/n_average; dp->b = ba/n_average; dp->a = aa/n_average; /* * Advance destination pointer */ dp++; } // dst x loop // next box-y sp = (tColorRGBA *)((Uint8*)osp + src->pitch*factory); /* * Advance destination pointers */ dp = (tColorRGBA *) ((Uint8 *) dp + dgap); } // dst y loop return (0); } /* 8bit integer-factor averaging Shrinker Shrinks 8bit Y 'src' surface to 'dst' surface. */ int shrinkSurfaceY(SDL_Surface * src, SDL_Surface * dst, int factorx, int factory) { int x, y, dx, dy, sgap, dgap, a; int n_average; Uint8 *sp, *osp, *oosp; Uint8 *dp; /* * Averaging integer shrink */ /* Precalculate division factor */ n_average = factorx*factory; /* * Scan destination */ sp = (Uint8 *) src->pixels; sgap = src->pitch - src->w; dp = (Uint8 *) dst->pixels; dgap = dst->pitch - dst->w; for (y = 0; y < dst->h; y++) { osp=sp; for (x = 0; x < dst->w; x++) { /* Trace out source box and accumulate */ oosp=sp; a=0; for (dy=0; dy < factory; dy++) { for (dx=0; dx < factorx; dx++) { a += (*sp); sp++; // next x } // src dx loop sp = (Uint8 *)((Uint8*)sp + (src->pitch - factorx)); // next y } // src dy loop // next box-x sp = (Uint8 *)((Uint8*)oosp + factorx); /* Store result in destination */ *dp = a/n_average; /* * Advance destination pointer */ dp++; } // dst x loop // next box-y sp = (Uint8 *)((Uint8*)osp + src->pitch*factory); /* * Advance destination pointers */ dp = (Uint8 *)((Uint8 *)dp + dgap); } // dst y loop return (0); } /* 32bit Zoomer with optional anti-aliasing by bilinear interpolation. Zoomes 32bit RGBA/ABGR 'src' surface to 'dst' surface. */ int zoomSurfaceRGBA(SDL_Surface * src, SDL_Surface * dst, int flipx, int flipy, int smooth) { int x, y, sx, sy, *sax, *say, *csax, *csay, csx, csy, ex, ey, t1, t2, sstep; tColorRGBA *c00, *c01, *c10, *c11; tColorRGBA *sp, *csp, *dp; int dgap; /* * Variable setup */ if (smooth) { /* * For interpolation: assume source dimension is one pixel */ /* * smaller to avoid overflow on right and bottom edge. */ sx = (int) (65536.0 * (float) (src->w - 1) / (float) dst->w); sy = (int) (65536.0 * (float) (src->h - 1) / (float) dst->h); } else { sx = (int) (65536.0 * (float) src->w / (float) dst->w); sy = (int) (65536.0 * (float) src->h / (float) dst->h); } /* * Allocate memory for row increments */ if ((sax = (int *) malloc((dst->w + 1) * sizeof(Uint32))) == NULL) { return (-1); } if ((say = (int *) malloc((dst->h + 1) * sizeof(Uint32))) == NULL) { free(sax); return (-1); } /* * Precalculate row increments */ sp = csp = (tColorRGBA *) src->pixels; dp = (tColorRGBA *) dst->pixels; if (flipx) csp += (src->w-1); if (flipy) csp = (tColorRGBA*)( (Uint8*)csp + src->pitch*(src->h-1) ); csx = 0; csax = sax; for (x = 0; x <= dst->w; x++) { *csax = csx; csax++; csx &= 0xffff; csx += sx; } csy = 0; csay = say; for (y = 0; y <= dst->h; y++) { *csay = csy; csay++; csy &= 0xffff; csy += sy; } dgap = dst->pitch - dst->w * 4; /* * Switch between interpolating and non-interpolating code */ if (smooth) { /* * Interpolating Zoom */ /* * Scan destination */ csay = say; for (y = 0; y < dst->h; y++) { /* * Setup color source pointers */ c00 = csp; c01 = csp; c01++; c10 = (tColorRGBA *) ((Uint8 *) csp + src->pitch); c11 = c10; c11++; csax = sax; for (x = 0; x < dst->w; x++) { /* * Interpolate colors */ ex = (*csax & 0xffff); ey = (*csay & 0xffff); t1 = ((((c01->r - c00->r) * ex) >> 16) + c00->r) & 0xff; t2 = ((((c11->r - c10->r) * ex) >> 16) + c10->r) & 0xff; dp->r = (((t2 - t1) * ey) >> 16) + t1; t1 = ((((c01->g - c00->g) * ex) >> 16) + c00->g) & 0xff; t2 = ((((c11->g - c10->g) * ex) >> 16) + c10->g) & 0xff; dp->g = (((t2 - t1) * ey) >> 16) + t1; t1 = ((((c01->b - c00->b) * ex) >> 16) + c00->b) & 0xff; t2 = ((((c11->b - c10->b) * ex) >> 16) + c10->b) & 0xff; dp->b = (((t2 - t1) * ey) >> 16) + t1; t1 = ((((c01->a - c00->a) * ex) >> 16) + c00->a) & 0xff; t2 = ((((c11->a - c10->a) * ex) >> 16) + c10->a) & 0xff; dp->a = (((t2 - t1) * ey) >> 16) + t1; /* * Advance source pointers */ csax++; sstep = (*csax >> 16); c00 += sstep; c01 += sstep; c10 += sstep; c11 += sstep; /* * Advance destination pointer */ dp++; } /* * Advance source pointer */ csay++; csp = (tColorRGBA *) ((Uint8 *) csp + (*csay >> 16) * src->pitch); /* * Advance destination pointers */ dp = (tColorRGBA *) ((Uint8 *) dp + dgap); } } else { /* * Non-Interpolating Zoom */ csay = say; for (y = 0; y < dst->h; y++) { sp = csp; csax = sax; for (x = 0; x < dst->w; x++) { /* * Draw */ *dp = *sp; /* * Advance source pointers */ csax++; sstep = (*csax >> 16); if (flipx) sstep = -sstep; sp += sstep; /* * Advance destination pointer */ dp++; } /* * Advance source pointer */ csay++; sstep = (*csay >> 16) * src->pitch; if (flipy) sstep = -sstep; csp = (tColorRGBA *) ((Uint8 *) csp + sstep); /* * Advance destination pointers */ dp = (tColorRGBA *) ((Uint8 *) dp + dgap); } } /* * Remove temp arrays */ free(sax); free(say); return (0); } /* 8bit Zoomer without smoothing. Zoomes 8bit palette/Y 'src' surface to 'dst' surface. */ int zoomSurfaceY(SDL_Surface * src, SDL_Surface * dst, int flipx, int flipy) { Uint32 x, y, sx, sy, *sax, *say, *csax, *csay, csx, csy; Uint8 *sp, *dp, *csp; int dgap; /* * Variable setup */ sx = (Uint32) (65536.0 * (float) src->w / (float) dst->w); sy = (Uint32) (65536.0 * (float) src->h / (float) dst->h); /* * Allocate memory for row increments */ if ((sax = (Uint32 *) malloc(dst->w * sizeof(Uint32))) == NULL) { return (-1); } if ((say = (Uint32 *) malloc(dst->h * sizeof(Uint32))) == NULL) { if (sax != NULL) { free(sax); } return (-1); } /* * Precalculate row increments */ csx = 0; csax = sax; for (x = 0; x < dst->w; x++) { csx += sx; *csax = (csx >> 16); csx &= 0xffff; csax++; } csy = 0; csay = say; for (y = 0; y < dst->h; y++) { csy += sy; *csay = (csy >> 16); csy &= 0xffff; csay++; } csx = 0; csax = sax; for (x = 0; x < dst->w; x++) { csx += (*csax); csax++; } csy = 0; csay = say; for (y = 0; y < dst->h; y++) { csy += (*csay); csay++; } /* * Pointer setup */ sp = csp = (Uint8 *) src->pixels; dp = (Uint8 *) dst->pixels; dgap = dst->pitch - dst->w; /* * Draw */ csay = say; for (y = 0; y < dst->h; y++) { csax = sax; sp = csp; for (x = 0; x < dst->w; x++) { /* * Draw */ *dp = *sp; /* * Advance source pointers */ sp += (*csax); csax++; /* * Advance destination pointer */ dp++; } /* * Advance source pointer (for row) */ csp += ((*csay) * src->pitch); csay++; /* * Advance destination pointers */ dp += dgap; } /* * Remove temp arrays */ free(sax); free(say); return (0); } /* 32bit Rotozoomer with optional anti-aliasing by bilinear interpolation. Rotates and zoomes 32bit RGBA/ABGR 'src' surface to 'dst' surface. */ void transformSurfaceRGBA(SDL_Surface * src, SDL_Surface * dst, int cx, int cy, int isin, int icos, int flipx, int flipy, int smooth) { int x, y, t1, t2, dx, dy, xd, yd, sdx, sdy, ax, ay, ex, ey, sw, sh; tColorRGBA c00, c01, c10, c11; tColorRGBA *pc, *sp; int gap; /* * Variable setup */ xd = ((src->w - dst->w) << 15); yd = ((src->h - dst->h) << 15); ax = (cx << 16) - (icos * cx); ay = (cy << 16) - (isin * cx); sw = src->w - 1; sh = src->h - 1; pc = dst->pixels; gap = dst->pitch - dst->w * 4; /* * Switch between interpolating and non-interpolating code */ if (smooth) { for (y = 0; y < dst->h; y++) { dy = cy - y; sdx = (ax + (isin * dy)) + xd; sdy = (ay - (icos * dy)) + yd; for (x = 0; x < dst->w; x++) { dx = (sdx >> 16); dy = (sdy >> 16); if ((dx >= -1) && (dy >= -1) && (dx < src->w) && (dy < src->h)) { if ((dx >= 0) && (dy >= 0) && (dx < sw) && (dy < sh)) { sp = (tColorRGBA *) ((Uint8 *) src->pixels + src->pitch * dy); sp += dx; c00 = *sp; sp += 1; c01 = *sp; sp = (tColorRGBA *) ((Uint8 *) sp + src->pitch); sp -= 1; c10 = *sp; sp += 1; c11 = *sp; } else if ((dx == sw) && (dy == sh)) { sp = (tColorRGBA *) ((Uint8 *) src->pixels + src->pitch * dy); sp += dx; c00 = *sp; c01 = *sp; c10 = *sp; c11 = *sp; } else if ((dx == -1) && (dy == -1)) { sp = (tColorRGBA *) (src->pixels); c00 = *sp; c01 = *sp; c10 = *sp; c11 = *sp; } else if ((dx == -1) && (dy == sh)) { sp = (tColorRGBA *) (src->pixels); sp = (tColorRGBA *) ((Uint8 *) src->pixels + src->pitch * dy); c00 = *sp; c01 = *sp; c10 = *sp; c11 = *sp; } else if ((dx == sw) && (dy == -1)) { sp = (tColorRGBA *) (src->pixels); sp += dx; c00 = *sp; c01 = *sp; c10 = *sp; c11 = *sp; } else if (dx == -1) { sp = (tColorRGBA *) ((Uint8 *) src->pixels + src->pitch * dy); c00 = *sp; c01 = *sp; c10 = *sp; sp = (tColorRGBA *) ((Uint8 *) sp + src->pitch); c11 = *sp; } else if (dy == -1) { sp = (tColorRGBA *) (src->pixels); sp += dx; c00 = *sp; c01 = *sp; c10 = *sp; sp += 1; c11 = *sp; } else if (dx == sw) { sp = (tColorRGBA *) ((Uint8 *) src->pixels + src->pitch * dy); sp += dx; c00 = *sp; c01 = *sp; sp = (tColorRGBA *) ((Uint8 *) sp + src->pitch); c10 = *sp; c11 = *sp; } else if (dy == sh) { sp = (tColorRGBA *) ((Uint8 *) src->pixels + src->pitch * dy); sp += dx; c00 = *sp; sp += 1; c01 = *sp; c10 = *sp; c11 = *sp; } /* * Interpolate colors */ ex = (sdx & 0xffff); ey = (sdy & 0xffff); t1 = ((((c01.r - c00.r) * ex) >> 16) + c00.r) & 0xff; t2 = ((((c11.r - c10.r) * ex) >> 16) + c10.r) & 0xff; pc->r = (((t2 - t1) * ey) >> 16) + t1; t1 = ((((c01.g - c00.g) * ex) >> 16) + c00.g) & 0xff; t2 = ((((c11.g - c10.g) * ex) >> 16) + c10.g) & 0xff; pc->g = (((t2 - t1) * ey) >> 16) + t1; t1 = ((((c01.b - c00.b) * ex) >> 16) + c00.b) & 0xff; t2 = ((((c11.b - c10.b) * ex) >> 16) + c10.b) & 0xff; pc->b = (((t2 - t1) * ey) >> 16) + t1; t1 = ((((c01.a - c00.a) * ex) >> 16) + c00.a) & 0xff; t2 = ((((c11.a - c10.a) * ex) >> 16) + c10.a) & 0xff; pc->a = (((t2 - t1) * ey) >> 16) + t1; } sdx += icos; sdy += isin; pc++; } pc = (tColorRGBA *) ((Uint8 *) pc + gap); } } else { for (y = 0; y < dst->h; y++) { dy = cy - y; sdx = (ax + (isin * dy)) + xd; sdy = (ay - (icos * dy)) + yd; for (x = 0; x < dst->w; x++) { dx = (short) (sdx >> 16); dy = (short) (sdy >> 16); if (flipx) dx = (src->w-1)-dx; if (flipy) dy = (src->h-1)-dy; if ((dx >= 0) && (dy >= 0) && (dx < src->w) && (dy < src->h)) { sp = (tColorRGBA *) ((Uint8 *) src->pixels + src->pitch * dy); sp += dx; *pc = *sp; } sdx += icos; sdy += isin; pc++; } pc = (tColorRGBA *) ((Uint8 *) pc + gap); } } } /* 8bit Rotozoomer without smoothing Rotates and zoomes 8bit palette/Y 'src' surface to 'dst' surface. */ void transformSurfaceY(SDL_Surface * src, SDL_Surface * dst, int cx, int cy, int isin, int icos) { int x, y, dx, dy, xd, yd, sdx, sdy, ax, ay, sw, sh; tColorY *pc, *sp; int gap; /* * Variable setup */ xd = ((src->w - dst->w) << 15); yd = ((src->h - dst->h) << 15); ax = (cx << 16) - (icos * cx); ay = (cy << 16) - (isin * cx); sw = src->w - 1; sh = src->h - 1; pc = dst->pixels; gap = dst->pitch - dst->w; /* * Clear surface to colorkey */ memset(pc, (unsigned char) (src->format->colorkey & 0xff), dst->pitch * dst->h); /* * Iterate through destination surface */ for (y = 0; y < dst->h; y++) { dy = cy - y; sdx = (ax + (isin * dy)) + xd; sdy = (ay - (icos * dy)) + yd; for (x = 0; x < dst->w; x++) { dx = (short) (sdx >> 16); dy = (short) (sdy >> 16); if ((dx >= 0) && (dy >= 0) && (dx < src->w) && (dy < src->h)) { sp = (tColorY *) (src->pixels); sp += (src->pitch * dy + dx); *pc = *sp; } sdx += icos; sdy += isin; pc++; } pc += gap; } } /* 32bit specialized 90degree rotator Rotates and zooms 'src' surface to 'dst' surface in 90degree increments. (contributed by Jeff Schiller) */ SDL_Surface* rotateSurface90Degrees(SDL_Surface* pSurf, int numClockwiseTurns) { int row, col; // Has to be a valid surface pointer and only 32-bit surfaces (for now) if (!pSurf || pSurf->format->BitsPerPixel != 32) { return NULL; } // normalize numClockwiseTurns while(numClockwiseTurns < 0) { numClockwiseTurns += 4; } numClockwiseTurns = (numClockwiseTurns % 4); // if it's even, our new width will be the same as the source surface int newWidth = (numClockwiseTurns % 2) ? (pSurf->h) : (pSurf->w); int newHeight = (numClockwiseTurns % 2) ? (pSurf->w) : (pSurf->h); SDL_Surface* pSurfOut = SDL_CreateRGBSurface( pSurf->flags, newWidth, newHeight, pSurf->format->BitsPerPixel, pSurf->format->Rmask, pSurf->format->Gmask, pSurf->format->Bmask, pSurf->format->Amask); if(!pSurfOut) { return NULL; } if(numClockwiseTurns != 0) { SDL_LockSurface(pSurf); SDL_LockSurface(pSurfOut); switch(numClockwiseTurns) { // rotate clockwise case 1: // rotated 90 degrees clockwise { Uint32* srcBuf = NULL; Uint32* dstBuf = NULL; for (row = 0; row < pSurf->h; ++row) { srcBuf = (Uint32*)(pSurf->pixels) + (row*pSurf->pitch/4); dstBuf = (Uint32*)(pSurfOut->pixels) + (pSurfOut->w - row - 1); for (col = 0; col < pSurf->w; ++col) { *dstBuf = *srcBuf; ++srcBuf; dstBuf += pSurfOut->pitch/4; } // for(col) } // for(row) } break; case 2: // rotated 180 degrees clockwise { Uint32* srcBuf = NULL; Uint32* dstBuf = NULL; for(row = 0; row < pSurf->h; ++row) { srcBuf = (Uint32*)(pSurf->pixels) + (row*pSurf->pitch/4); dstBuf = (Uint32*)(pSurfOut->pixels) + ((pSurfOut->h - row - 1)*pSurfOut->pitch/4) + (pSurfOut->w - 1); for(col = 0; col < pSurf->w; ++col) { *dstBuf = *srcBuf; ++srcBuf; --dstBuf; } // for(col) } // for(row) } break; case 3: { Uint32* srcBuf = NULL; Uint32* dstBuf = NULL; for(row = 0; row < pSurf->h; ++row) { srcBuf = (Uint32*)(pSurf->pixels) + (row*pSurf->pitch/4); dstBuf = (Uint32*)(pSurfOut->pixels) + row + ((pSurfOut->h - 1)*pSurfOut->pitch/4); for(col = 0; col < pSurf->w; ++col) { *dstBuf = *srcBuf; ++srcBuf; dstBuf -= pSurfOut->pitch/4; } // for(col) } // for(row) } break; } // switch SDL_UnlockSurface(pSurf); SDL_UnlockSurface(pSurfOut); } // if numClockwiseTurns > 0 else { // simply copy surface to output if(SDL_BlitSurface(pSurf, NULL, pSurfOut, NULL)) { return NULL; } } return pSurfOut; } /* rotozoomSurface() Rotates and zoomes a 32bit or 8bit 'src' surface to newly created 'dst' surface. 'angle' is the rotation in degrees. 'zoom' a scaling factor. If 'smooth' is 1 then the destination 32bit surface is anti-aliased. If the surface is not 8bit or 32bit RGBA/ABGR it will be converted into a 32bit RGBA format on the fly. */ #define VALUE_LIMIT 0.001 /* Local rotozoom-size function with trig result return */ void rotozoomSurfaceSizeTrig(int width, int height, double angle, double zoomx, double zoomy, int *dstwidth, int *dstheight, double *canglezoom, double *sanglezoom) { double x, y, cx, cy, sx, sy; double radangle; int dstwidthhalf, dstheighthalf; /* * Determine destination width and height by rotating a centered source box */ radangle = angle * (M_PI / 180.0); *sanglezoom = sin(radangle); *canglezoom = cos(radangle); *sanglezoom *= zoomx; *canglezoom *= zoomx; x = width / 2; y = height / 2; cx = *canglezoom * x; cy = *canglezoom * y; sx = *sanglezoom * x; sy = *sanglezoom * y; dstwidthhalf = MAX((int) ceil(MAX(MAX(MAX(fabs(cx + sy), fabs(cx - sy)), fabs(-cx + sy)), fabs(-cx - sy))), 1); dstheighthalf = MAX((int) ceil(MAX(MAX(MAX(fabs(sx + cy), fabs(sx - cy)), fabs(-sx + cy)), fabs(-sx - cy))), 1); *dstwidth = 2 * dstwidthhalf; *dstheight = 2 * dstheighthalf; } /* Publically available rotozoom-size function */ void rotozoomSurfaceSizeXY(int width, int height, double angle, double zoomx, double zoomy, int *dstwidth, int *dstheight) { double dummy_sanglezoom, dummy_canglezoom; rotozoomSurfaceSizeTrig(width, height, angle, zoomx, zoomy, dstwidth, dstheight, &dummy_sanglezoom, &dummy_canglezoom); } /* Publically available rotozoom-size function */ void rotozoomSurfaceSize(int width, int height, double angle, double zoom, int *dstwidth, int *dstheight) { double dummy_sanglezoom, dummy_canglezoom; rotozoomSurfaceSizeTrig(width, height, angle, zoom, zoom, dstwidth, dstheight, &dummy_sanglezoom, &dummy_canglezoom); } /* Publically available rotozoom function */ SDL_Surface *rotozoomSurface(SDL_Surface * src, double angle, double zoom, int smooth) { return rotozoomSurfaceXY(src, angle, zoom, zoom, smooth); } /* Publically available rotozoom function */ SDL_Surface *rotozoomSurfaceXY(SDL_Surface * src, double angle, double zoomx, double zoomy, int smooth) { SDL_Surface *rz_src; SDL_Surface *rz_dst; double zoominv; double sanglezoom, canglezoom, sanglezoominv, canglezoominv; int dstwidthhalf, dstwidth, dstheighthalf, dstheight; int is32bit; int i, src_converted; int flipx,flipy; Uint8 r,g,b; Uint32 colorkey; int colorKeyAvailable = 0; /* * Sanity check */ if (src == NULL) return (NULL); if( src->flags & SDL_SRCCOLORKEY ) { colorkey = src->format->colorkey; SDL_GetRGB(colorkey, src->format, &r, &g, &b); colorKeyAvailable = 1; } /* * Determine if source surface is 32bit or 8bit */ is32bit = (src->format->BitsPerPixel == 32); if ((is32bit) || (src->format->BitsPerPixel == 8)) { /* * Use source surface 'as is' */ rz_src = src; src_converted = 0; } else { /* * New source surface is 32bit with a defined RGBA ordering */ rz_src = SDL_CreateRGBSurface(SDL_SWSURFACE, src->w, src->h, 32, #if SDL_BYTEORDER == SDL_LIL_ENDIAN 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000 #else 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff #endif ); if(colorKeyAvailable) SDL_SetColorKey(src, 0, 0); SDL_BlitSurface(src, NULL, rz_src, NULL); if(colorKeyAvailable) SDL_SetColorKey(src, SDL_SRCCOLORKEY, colorkey); src_converted = 1; is32bit = 1; } /* * Sanity check zoom factor */ flipx = (zoomx<0); if (flipx) zoomx=-zoomx; flipy = (zoomy<0); if (flipy) zoomy=-zoomy; if (zoomx < VALUE_LIMIT) zoomx = VALUE_LIMIT; if (zoomy < VALUE_LIMIT) zoomy = VALUE_LIMIT; zoominv = 65536.0 / (zoomx * zoomx); /* * Check if we have a rotozoom or just a zoom */ if (fabs(angle) > VALUE_LIMIT) { /* * Angle!=0: full rotozoom */ /* * ----------------------- */ /* Determine target size */ rotozoomSurfaceSizeTrig(rz_src->w, rz_src->h, angle, zoomx, zoomy, &dstwidth, &dstheight, &canglezoom, &sanglezoom); /* * Calculate target factors from sin/cos and zoom */ sanglezoominv = sanglezoom; canglezoominv = canglezoom; sanglezoominv *= zoominv; canglezoominv *= zoominv; /* Calculate half size */ dstwidthhalf = dstwidth / 2; dstheighthalf = dstheight / 2; /* * Alloc space to completely contain the rotated surface */ rz_dst = NULL; if (is32bit) { /* * Target surface is 32bit with source RGBA/ABGR ordering */ rz_dst = SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 32, rz_src->format->Rmask, rz_src->format->Gmask, rz_src->format->Bmask, rz_src->format->Amask); } else { /* * Target surface is 8bit */ rz_dst = SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 8, 0, 0, 0, 0); } if (colorKeyAvailable == 1){ colorkey = SDL_MapRGB(rz_dst->format, r, g, b); SDL_FillRect(rz_dst, NULL, colorkey ); } /* * Lock source surface */ SDL_LockSurface(rz_src); /* * Check which kind of surface we have */ if (is32bit) { /* * Call the 32bit transformation routine to do the rotation (using alpha) */ transformSurfaceRGBA(rz_src, rz_dst, dstwidthhalf, dstheighthalf, (int) (sanglezoominv), (int) (canglezoominv), flipx, flipy, smooth); /* * Turn on source-alpha support */ SDL_SetAlpha(rz_dst, SDL_SRCALPHA, 255); } else { /* * Copy palette and colorkey info */ for (i = 0; i < rz_src->format->palette->ncolors; i++) { rz_dst->format->palette->colors[i] = rz_src->format->palette->colors[i]; } rz_dst->format->palette->ncolors = rz_src->format->palette->ncolors; /* * Call the 8bit transformation routine to do the rotation */ transformSurfaceY(rz_src, rz_dst, dstwidthhalf, dstheighthalf, (int) (sanglezoominv), (int) (canglezoominv)); SDL_SetColorKey(rz_dst, SDL_SRCCOLORKEY | SDL_RLEACCEL, rz_src->format->colorkey); } /* * Unlock source surface */ SDL_UnlockSurface(rz_src); } else { /* * Angle=0: Just a zoom */ /* * -------------------- */ /* * Calculate target size */ zoomSurfaceSize(rz_src->w, rz_src->h, zoomx, zoomy, &dstwidth, &dstheight); /* * Alloc space to completely contain the zoomed surface */ rz_dst = NULL; if (is32bit) { /* * Target surface is 32bit with source RGBA/ABGR ordering */ rz_dst = SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 32, rz_src->format->Rmask, rz_src->format->Gmask, rz_src->format->Bmask, rz_src->format->Amask); } else { /* * Target surface is 8bit */ rz_dst = SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 8, 0, 0, 0, 0); } if (colorKeyAvailable == 1){ colorkey = SDL_MapRGB(rz_dst->format, r, g, b); SDL_FillRect(rz_dst, NULL, colorkey ); } /* * Lock source surface */ SDL_LockSurface(rz_src); /* * Check which kind of surface we have */ if (is32bit) { /* * Call the 32bit transformation routine to do the zooming (using alpha) */ zoomSurfaceRGBA(rz_src, rz_dst, flipx, flipy, smooth); /* * Turn on source-alpha support */ SDL_SetAlpha(rz_dst, SDL_SRCALPHA, 255); } else { /* * Copy palette and colorkey info */ for (i = 0; i < rz_src->format->palette->ncolors; i++) { rz_dst->format->palette->colors[i] = rz_src->format->palette->colors[i]; } rz_dst->format->palette->ncolors = rz_src->format->palette->ncolors; /* * Call the 8bit transformation routine to do the zooming */ zoomSurfaceY(rz_src, rz_dst, flipx, flipy); SDL_SetColorKey(rz_dst, SDL_SRCCOLORKEY | SDL_RLEACCEL, rz_src->format->colorkey); } /* * Unlock source surface */ SDL_UnlockSurface(rz_src); } /* * Cleanup temp surface */ if (src_converted) { SDL_FreeSurface(rz_src); } /* * Return destination surface */ return (rz_dst); } /* zoomSurface() Zoomes a 32bit or 8bit 'src' surface to newly created 'dst' surface. 'zoomx' and 'zoomy' are scaling factors for width and height. If 'smooth' is 1 then the destination 32bit surface is anti-aliased. If the surface is not 8bit or 32bit RGBA/ABGR it will be converted into a 32bit RGBA format on the fly. */ #define VALUE_LIMIT 0.001 void zoomSurfaceSize(int width, int height, double zoomx, double zoomy, int *dstwidth, int *dstheight) { /* * Sanity check zoom factors */ if (zoomx < VALUE_LIMIT) { zoomx = VALUE_LIMIT; } if (zoomy < VALUE_LIMIT) { zoomy = VALUE_LIMIT; } /* * Calculate target size */ *dstwidth = (int) ((double) width * zoomx); *dstheight = (int) ((double) height * zoomy); if (*dstwidth < 1) { *dstwidth = 1; } if (*dstheight < 1) { *dstheight = 1; } } SDL_Surface *zoomSurface(SDL_Surface * src, double zoomx, double zoomy, int smooth) { SDL_Surface *rz_src; SDL_Surface *rz_dst; int dstwidth, dstheight; int is32bit; int i, src_converted; int flipx, flipy; /* * Sanity check */ if (src == NULL) return (NULL); /* * Determine if source surface is 32bit or 8bit */ is32bit = (src->format->BitsPerPixel == 32); if ((is32bit) || (src->format->BitsPerPixel == 8)) { /* * Use source surface 'as is' */ rz_src = src; src_converted = 0; } else { /* * New source surface is 32bit with a defined RGBA ordering */ rz_src = SDL_CreateRGBSurface(SDL_SWSURFACE, src->w, src->h, 32, #if SDL_BYTEORDER == SDL_LIL_ENDIAN 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000 #else 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff #endif ); SDL_BlitSurface(src, NULL, rz_src, NULL); src_converted = 1; is32bit = 1; } flipx = (zoomx<0); if (flipx) zoomx = -zoomx; flipy = (zoomy<0); if (flipy) zoomy = -zoomy; /* Get size if target */ zoomSurfaceSize(rz_src->w, rz_src->h, zoomx, zoomy, &dstwidth, &dstheight); /* * Alloc space to completely contain the zoomed surface */ rz_dst = NULL; if (is32bit) { /* * Target surface is 32bit with source RGBA/ABGR ordering */ rz_dst = SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 32, rz_src->format->Rmask, rz_src->format->Gmask, rz_src->format->Bmask, rz_src->format->Amask); } else { /* * Target surface is 8bit */ rz_dst = SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 8, 0, 0, 0, 0); } /* * Lock source surface */ SDL_LockSurface(rz_src); /* * Check which kind of surface we have */ if (is32bit) { /* * Call the 32bit transformation routine to do the zooming (using alpha) */ zoomSurfaceRGBA(rz_src, rz_dst, flipx, flipy, smooth); /* * Turn on source-alpha support */ SDL_SetAlpha(rz_dst, SDL_SRCALPHA, 255); } else { /* * Copy palette and colorkey info */ for (i = 0; i < rz_src->format->palette->ncolors; i++) { rz_dst->format->palette->colors[i] = rz_src->format->palette->colors[i]; } rz_dst->format->palette->ncolors = rz_src->format->palette->ncolors; /* * Call the 8bit transformation routine to do the zooming */ zoomSurfaceY(rz_src, rz_dst, flipx, flipy); SDL_SetColorKey(rz_dst, SDL_SRCCOLORKEY | SDL_RLEACCEL, rz_src->format->colorkey); } /* * Unlock source surface */ SDL_UnlockSurface(rz_src); /* * Cleanup temp surface */ if (src_converted) { SDL_FreeSurface(rz_src); } /* * Return destination surface */ return (rz_dst); } SDL_Surface *shrinkSurface(SDL_Surface * src, int factorx, int factory) { SDL_Surface *rz_src; SDL_Surface *rz_dst; int dstwidth, dstheight; int is32bit; int i, src_converted; /* * Sanity check */ if (src == NULL) return (NULL); /* * Determine if source surface is 32bit or 8bit */ is32bit = (src->format->BitsPerPixel == 32); if ((is32bit) || (src->format->BitsPerPixel == 8)) { /* * Use source surface 'as is' */ rz_src = src; src_converted = 0; } else { /* * New source surface is 32bit with a defined RGBA ordering */ rz_src = SDL_CreateRGBSurface(SDL_SWSURFACE, src->w, src->h, 32, #if SDL_BYTEORDER == SDL_LIL_ENDIAN 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000 #else 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff #endif ); SDL_BlitSurface(src, NULL, rz_src, NULL); src_converted = 1; is32bit = 1; } /* Get size for target */ dstwidth=rz_src->w/factorx; while (dstwidth*factorx>rz_src->w) { dstwidth--; } dstheight=rz_src->h/factory; while (dstheight*factory>rz_src->h) { dstheight--; } /* * Alloc space to completely contain the shrunken surface */ rz_dst = NULL; if (is32bit) { /* * Target surface is 32bit with source RGBA/ABGR ordering */ rz_dst = SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 32, rz_src->format->Rmask, rz_src->format->Gmask, rz_src->format->Bmask, rz_src->format->Amask); } else { /* * Target surface is 8bit */ rz_dst = SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 8, 0, 0, 0, 0); } /* * Lock source surface */ SDL_LockSurface(rz_src); /* * Check which kind of surface we have */ if (is32bit) { /* * Call the 32bit transformation routine to do the shrinking (using alpha) */ shrinkSurfaceRGBA(rz_src, rz_dst, factorx, factory); /* * Turn on source-alpha support */ SDL_SetAlpha(rz_dst, SDL_SRCALPHA, 255); } else { /* * Copy palette and colorkey info */ for (i = 0; i < rz_src->format->palette->ncolors; i++) { rz_dst->format->palette->colors[i] = rz_src->format->palette->colors[i]; } rz_dst->format->palette->ncolors = rz_src->format->palette->ncolors; /* * Call the 8bit transformation routine to do the shrinking */ shrinkSurfaceY(rz_src, rz_dst, factorx, factory); SDL_SetColorKey(rz_dst, SDL_SRCCOLORKEY | SDL_RLEACCEL, rz_src->format->colorkey); } /* * Unlock source surface */ SDL_UnlockSurface(rz_src); /* * Cleanup temp surface */ if (src_converted) { SDL_FreeSurface(rz_src); } /* * Return destination surface */ return (rz_dst); }