diff options
Diffstat (limited to 'ui/sdl_zoom_template.h')
| -rw-r--r-- | ui/sdl_zoom_template.h | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/ui/sdl_zoom_template.h b/ui/sdl_zoom_template.h new file mode 100644 index 0000000000..64bbca849b --- /dev/null +++ b/ui/sdl_zoom_template.h @@ -0,0 +1,225 @@ +/* + * SDL_zoom_template - surface scaling + * + * Copyright (c) 2009 Citrix Systems, Inc. + * + * Derived from: SDL_rotozoom, LGPL (c) A. Schiffler from the SDL_gfx library. + * Modifications by Stefano Stabellini. + * + * This work is licensed under the terms of the GNU GPL version 2. + * See the COPYING file in the top-level directory. + * + */ + +#if BPP == 16 +#define SDL_TYPE Uint16 +#elif BPP == 32 +#define SDL_TYPE Uint32 +#else +#error unsupport depth +#endif + +/* + * Simple helper functions to make the code looks nicer + * + * Assume spf = source SDL_PixelFormat + * dpf = dest SDL_PixelFormat + * + */ +#define getRed(color) (((color) & spf->Rmask) >> spf->Rshift) +#define getGreen(color) (((color) & spf->Gmask) >> spf->Gshift) +#define getBlue(color) (((color) & spf->Bmask) >> spf->Bshift) +#define getAlpha(color) (((color) & spf->Amask) >> spf->Ashift) + +#define setRed(r, pcolor) do { \ + *pcolor = ((*pcolor) & (~(dpf->Rmask))) + \ + (((r) & (dpf->Rmask >> dpf->Rshift)) << dpf->Rshift); \ +} while (0); + +#define setGreen(g, pcolor) do { \ + *pcolor = ((*pcolor) & (~(dpf->Gmask))) + \ + (((g) & (dpf->Gmask >> dpf->Gshift)) << dpf->Gshift); \ +} while (0); + +#define setBlue(b, pcolor) do { \ + *pcolor = ((*pcolor) & (~(dpf->Bmask))) + \ + (((b) & (dpf->Bmask >> dpf->Bshift)) << dpf->Bshift); \ +} while (0); + +#define setAlpha(a, pcolor) do { \ + *pcolor = ((*pcolor) & (~(dpf->Amask))) + \ + (((a) & (dpf->Amask >> dpf->Ashift)) << dpf->Ashift); \ +} while (0); + +static int glue(sdl_zoom_rgb, BPP)(SDL_Surface *src, SDL_Surface *dst, int smooth, + SDL_Rect *dst_rect) +{ + int x, y, sx, sy, *sax, *say, *csax, *csay, csx, csy, ex, ey, t1, t2, sstep, sstep_jump; + SDL_TYPE *c00, *c01, *c10, *c11, *sp, *csp, *dp; + int d_gap; + SDL_PixelFormat *spf = src->format; + SDL_PixelFormat *dpf = dst->format; + + if (smooth) { + /* For interpolation: assume source dimension is one pixel. + * Smaller here 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); + } + + 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); + } + + sp = csp = (SDL_TYPE *) src->pixels; + dp = (SDL_TYPE *) (dst->pixels + dst_rect->y * dst->pitch + + dst_rect->x * dst->format->BytesPerPixel); + + 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; + } + + d_gap = dst->pitch - dst_rect->w * dst->format->BytesPerPixel; + + if (smooth) { + csay = say; + for (y = 0; y < dst_rect->y; y++) { + csay++; + sstep = (*csay >> 16) * src->pitch; + csp = (SDL_TYPE *) ((Uint8 *) csp + sstep); + } + + /* Calculate sstep_jump */ + csax = sax; + sstep_jump = 0; + for (x = 0; x < dst_rect->x; x++) { + csax++; + sstep = (*csax >> 16); + sstep_jump += sstep; + } + + for (y = 0; y < dst_rect->h ; y++) { + /* Setup colour source pointers */ + c00 = csp + sstep_jump; + c01 = c00 + 1; + c10 = (SDL_TYPE *) ((Uint8 *) csp + src->pitch) + sstep_jump; + c11 = c10 + 1; + csax = sax + dst_rect->x; + + for (x = 0; x < dst_rect->w; x++) { + + /* Interpolate colours */ + ex = (*csax & 0xffff); + ey = (*csay & 0xffff); + t1 = ((((getRed(*c01) - getRed(*c00)) * ex) >> 16) + + getRed(*c00)) & (dpf->Rmask >> dpf->Rshift); + t2 = ((((getRed(*c11) - getRed(*c10)) * ex) >> 16) + + getRed(*c10)) & (dpf->Rmask >> dpf->Rshift); + setRed((((t2 - t1) * ey) >> 16) + t1, dp); + t1 = ((((getGreen(*c01) - getGreen(*c00)) * ex) >> 16) + + getGreen(*c00)) & (dpf->Gmask >> dpf->Gshift); + t2 = ((((getGreen(*c11) - getGreen(*c10)) * ex) >> 16) + + getGreen(*c10)) & (dpf->Gmask >> dpf->Gshift); + setGreen((((t2 - t1) * ey) >> 16) + t1, dp); + t1 = ((((getBlue(*c01) - getBlue(*c00)) * ex) >> 16) + + getBlue(*c00)) & (dpf->Bmask >> dpf->Bshift); + t2 = ((((getBlue(*c11) - getBlue(*c10)) * ex) >> 16) + + getBlue(*c10)) & (dpf->Bmask >> dpf->Bshift); + setBlue((((t2 - t1) * ey) >> 16) + t1, dp); + t1 = ((((getAlpha(*c01) - getAlpha(*c00)) * ex) >> 16) + + getAlpha(*c00)) & (dpf->Amask >> dpf->Ashift); + t2 = ((((getAlpha(*c11) - getAlpha(*c10)) * ex) >> 16) + + getAlpha(*c10)) & (dpf->Amask >> dpf->Ashift); + setAlpha((((t2 - t1) * ey) >> 16) + t1, dp); + + /* Advance source pointers */ + csax++; + sstep = (*csax >> 16); + c00 += sstep; + c01 += sstep; + c10 += sstep; + c11 += sstep; + /* Advance destination pointer */ + dp++; + } + /* Advance source pointer */ + csay++; + csp = (SDL_TYPE *) ((Uint8 *) csp + (*csay >> 16) * src->pitch); + /* Advance destination pointers */ + dp = (SDL_TYPE *) ((Uint8 *) dp + d_gap); + } + + + } else { + csay = say; + + for (y = 0; y < dst_rect->y; y++) { + csay++; + sstep = (*csay >> 16) * src->pitch; + csp = (SDL_TYPE *) ((Uint8 *) csp + sstep); + } + + /* Calculate sstep_jump */ + csax = sax; + sstep_jump = 0; + for (x = 0; x < dst_rect->x; x++) { + csax++; + sstep = (*csax >> 16); + sstep_jump += sstep; + } + + for (y = 0 ; y < dst_rect->h ; y++) { + sp = csp + sstep_jump; + csax = sax + dst_rect->x; + + for (x = 0; x < dst_rect->w; x++) { + + /* Draw */ + *dp = *sp; + + /* Advance source pointers */ + csax++; + sstep = (*csax >> 16); + sp += sstep; + + /* Advance destination pointer */ + dp++; + } + /* Advance source pointers */ + csay++; + sstep = (*csay >> 16) * src->pitch; + csp = (SDL_TYPE *) ((Uint8 *) csp + sstep); + + /* Advance destination pointer */ + dp = (SDL_TYPE *) ((Uint8 *) dp + d_gap); + } + } + + free(sax); + free(say); + return (0); +} + +#undef SDL_TYPE + |