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-rw-r--r--src/sdl2gfx/SDL_rotozoom.c1651
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diff --git a/src/sdl2gfx/SDL_rotozoom.c b/src/sdl2gfx/SDL_rotozoom.c
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--- a/src/sdl2gfx/SDL_rotozoom.c
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@@ -1,1651 +0,0 @@
-/*
-
-SDL2_rotozoom.c: rotozoomer, zoomer and shrinker for 32bit or 8bit surfaces
-
-Copyright (C) 2012 Andreas Schiffler
-
-This software is provided 'as-is', without any express or implied
-warranty. In no event will the authors be held liable for any damages
-arising from the use of this software.
-
-Permission is granted to anyone to use this software for any purpose,
-including commercial applications, and to alter it and redistribute it
-freely, subject to the following restrictions:
-
-1. The origin of this software must not be misrepresented; you must not
-claim that you wrote the original software. If you use this software
-in a product, an acknowledgment in the product documentation would be
-appreciated but is not required.
-
-2. Altered source versions must be plainly marked as such, and must not be
-misrepresented as being the original software.
-
-3. This notice may not be removed or altered from any source
-distribution.
-
-Andreas Schiffler -- aschiffler at ferzkopp dot net
-
-*/
-
-#ifdef WIN32
-#include <windows.h>
-#endif
-
-#include <stdlib.h>
-#include <string.h>
-
-#include "SDL_rotozoom.h"
-
-/* ---- Internally used structures */
-
-/*!
-\brief A 32 bit RGBA pixel.
-*/
-typedef struct tColorRGBA {
- Uint8 r;
- Uint8 g;
- Uint8 b;
- Uint8 a;
-} tColorRGBA;
-
-/*!
-\brief A 8bit Y/palette pixel.
-*/
-typedef struct tColorY {
- Uint8 y;
-} tColorY;
-
-/*!
-\brief Returns maximum of two numbers a and b.
-*/
-#define MAX(a,b) (((a) > (b)) ? (a) : (b))
-
-/*!
-\brief Number of guard rows added to destination surfaces.
-
-This is a simple but effective workaround for observed issues.
-These rows allocate extra memory and are then hidden from the surface.
-Rows are added to the end of destination surfaces when they are allocated.
-This catches any potential overflows which seem to happen with
-just the right src image dimensions and scale/rotation and can lead
-to a situation where the program can segfault.
-*/
-#define GUARD_ROWS (2)
-
-/*!
-\brief Lower limit of absolute zoom factor or rotation degrees.
-*/
-#define VALUE_LIMIT 0.001
-
-/*!
-\brief Returns colorkey info for a surface
-*/
-Uint32 _colorkey(SDL_Surface *src)
-{
- Uint32 key = 0;
- SDL_GetColorKey(src, &key);
- return key;
-}
-
-
-/*!
-\brief Internal 32 bit integer-factor averaging Shrinker.
-
-Shrinks 32 bit RGBA/ABGR 'src' surface to 'dst' surface.
-Averages color and alpha values values of src pixels to calculate dst pixels.
-Assumes src and dst surfaces are of 32 bit depth.
-Assumes dst surface was allocated with the correct dimensions.
-
-\param src The surface to shrink (input).
-\param dst The shrunken surface (output).
-\param factorx The horizontal shrinking ratio.
-\param factory The vertical shrinking ratio.
-
-\return 0 for success or -1 for error.
-*/
-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);
-}
-
-/*!
-\brief Internal 8 bit integer-factor averaging shrinker.
-
-Shrinks 8bit Y 'src' surface to 'dst' surface.
-Averages color (brightness) values values of src pixels to calculate dst pixels.
-Assumes src and dst surfaces are of 8 bit depth.
-Assumes dst surface was allocated with the correct dimensions.
-
-\param src The surface to shrink (input).
-\param dst The shrunken surface (output).
-\param factorx The horizontal shrinking ratio.
-\param factory The vertical shrinking ratio.
-
-\return 0 for success or -1 for error.
-*/
-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);
- /* next x */
- sp++;
- }
- /* end src dx loop */
- /* next y */
- sp = (Uint8 *)((Uint8*)sp + (src->pitch - factorx));
- }
- /* end src dy loop */
-
- /* next box-x */
- sp = (Uint8 *)((Uint8*)oosp + factorx);
-
- /* Store result in destination */
- *dp = a/n_average;
-
- /*
- * Advance destination pointer
- */
- dp++;
- }
- /* end dst x loop */
-
- /* next box-y */
- sp = (Uint8 *)((Uint8*)osp + src->pitch*factory);
-
- /*
- * Advance destination pointers
- */
- dp = (Uint8 *)((Uint8 *)dp + dgap);
- }
- /* end dst y loop */
-
- return (0);
-}
-
-/*!
-\brief Internal 32 bit Zoomer with optional anti-aliasing by bilinear interpolation.
-
-Zooms 32 bit RGBA/ABGR 'src' surface to 'dst' surface.
-Assumes src and dst surfaces are of 32 bit depth.
-Assumes dst surface was allocated with the correct dimensions.
-
-\param src The surface to zoom (input).
-\param dst The zoomed surface (output).
-\param flipx Flag indicating if the image should be horizontally flipped.
-\param flipy Flag indicating if the image should be vertically flipped.
-\param smooth Antialiasing flag; set to SMOOTHING_ON to enable.
-
-\return 0 for success or -1 for error.
-*/
-int _zoomSurfaceRGBA(SDL_Surface * src, SDL_Surface * dst, int flipx, int flipy, int smooth)
-{
- int x, y, sx, sy, ssx, ssy, *sax, *say, *csax, *csay, *salast, csx, csy, ex, ey, cx, cy, sstep, sstepx, sstepy;
- tColorRGBA *c00, *c01, *c10, *c11;
- tColorRGBA *sp, *csp, *dp;
- int spixelgap, spixelw, spixelh, dgap, t1, t2;
-
- /*
- * Allocate memory for row/column 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
- */
- spixelw = (src->w - 1);
- spixelh = (src->h - 1);
- if (smooth) {
- sx = (int) (65536.0 * (float) spixelw / (float) (dst->w - 1));
- sy = (int) (65536.0 * (float) spixelh / (float) (dst->h - 1));
- } else {
- sx = (int) (65536.0 * (float) (src->w) / (float) (dst->w));
- sy = (int) (65536.0 * (float) (src->h) / (float) (dst->h));
- }
-
- /* Maximum scaled source size */
- ssx = (src->w << 16) - 1;
- ssy = (src->h << 16) - 1;
-
- /* Precalculate horizontal row increments */
- csx = 0;
- csax = sax;
- for (x = 0; x <= dst->w; x++) {
- *csax = csx;
- csax++;
- csx += sx;
-
- /* Guard from overflows */
- if (csx > ssx) {
- csx = ssx;
- }
- }
-
- /* Precalculate vertical row increments */
- csy = 0;
- csay = say;
- for (y = 0; y <= dst->h; y++) {
- *csay = csy;
- csay++;
- csy += sy;
-
- /* Guard from overflows */
- if (csy > ssy) {
- csy = ssy;
- }
- }
-
- sp = (tColorRGBA *) src->pixels;
- dp = (tColorRGBA *) dst->pixels;
- dgap = dst->pitch - dst->w * 4;
- spixelgap = src->pitch/4;
-
- if (flipx) sp += spixelw;
- if (flipy) sp += (spixelgap * spixelh);
-
- /*
- * Switch between interpolating and non-interpolating code
- */
- if (smooth) {
-
- /*
- * Interpolating Zoom
- */
- csay = say;
- for (y = 0; y < dst->h; y++) {
- csp = sp;
- csax = sax;
- for (x = 0; x < dst->w; x++) {
- /*
- * Setup color source pointers
- */
- ex = (*csax & 0xffff);
- ey = (*csay & 0xffff);
- cx = (*csax >> 16);
- cy = (*csay >> 16);
- sstepx = cx < spixelw;
- sstepy = cy < spixelh;
- c00 = sp;
- c01 = sp;
- c10 = sp;
- if (sstepy) {
- if (flipy) {
- c10 -= spixelgap;
- } else {
- c10 += spixelgap;
- }
- }
- c11 = c10;
- if (sstepx) {
- if (flipx) {
- c01--;
- c11--;
- } else {
- c01++;
- c11++;
- }
- }
-
- /*
- * Draw and interpolate colors
- */
- 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 pointer x
- */
- salast = csax;
- csax++;
- sstep = (*csax >> 16) - (*salast >> 16);
- if (flipx) {
- sp -= sstep;
- } else {
- sp += sstep;
- }
-
- /*
- * Advance destination pointer x
- */
- dp++;
- }
- /*
- * Advance source pointer y
- */
- salast = csay;
- csay++;
- sstep = (*csay >> 16) - (*salast >> 16);
- sstep *= spixelgap;
- if (flipy) {
- sp = csp - sstep;
- } else {
- sp = csp + sstep;
- }
-
- /*
- * Advance destination pointer y
- */
- dp = (tColorRGBA *) ((Uint8 *) dp + dgap);
- }
- } else {
- /*
- * Non-Interpolating Zoom
- */
- csay = say;
- for (y = 0; y < dst->h; y++) {
- csp = sp;
- csax = sax;
- for (x = 0; x < dst->w; x++) {
- /*
- * Draw
- */
- *dp = *sp;
-
- /*
- * Advance source pointer x
- */
- salast = csax;
- csax++;
- sstep = (*csax >> 16) - (*salast >> 16);
- if (flipx) sstep = -sstep;
- sp += sstep;
-
- /*
- * Advance destination pointer x
- */
- dp++;
- }
- /*
- * Advance source pointer y
- */
- salast = csay;
- csay++;
- sstep = (*csay >> 16) - (*salast >> 16);
- sstep *= spixelgap;
- if (flipy) sstep = -sstep;
- sp = csp + sstep;
-
- /*
- * Advance destination pointer y
- */
- dp = (tColorRGBA *) ((Uint8 *) dp + dgap);
- }
- }
-
- /*
- * Remove temp arrays
- */
- free(sax);
- free(say);
-
- return (0);
-}
-
-/*!
-
-\brief Internal 8 bit Zoomer without smoothing.
-
-Zooms 8bit palette/Y 'src' surface to 'dst' surface.
-Assumes src and dst surfaces are of 8 bit depth.
-Assumes dst surface was allocated with the correct dimensions.
-
-\param src The surface to zoom (input).
-\param dst The zoomed surface (output).
-\param flipx Flag indicating if the image should be horizontally flipped.
-\param flipy Flag indicating if the image should be vertically flipped.
-
-\return 0 for success or -1 for error.
-*/
-int _zoomSurfaceY(SDL_Surface * src, SDL_Surface * dst, int flipx, int flipy)
-{
- int x, y;
- Uint32 *sax, *say, *csax, *csay;
- int csx, csy;
- Uint8 *sp, *dp, *csp;
- int dgap;
-
- /*
- * Allocate memory for row increments
- */
- if ((sax = (Uint32 *) malloc((dst->w + 1) * sizeof(Uint32))) == NULL) {
- return (-1);
- }
- if ((say = (Uint32 *) malloc((dst->h + 1) * sizeof(Uint32))) == NULL) {
- free(sax);
- return (-1);
- }
-
- /*
- * Pointer setup
- */
- sp = csp = (Uint8 *) src->pixels;
- dp = (Uint8 *) dst->pixels;
- dgap = dst->pitch - dst->w;
-
- if (flipx) csp += (src->w-1);
- if (flipy) csp = ( (Uint8*)csp + src->pitch*(src->h-1) );
-
- /*
- * Precalculate row increments
- */
- csx = 0;
- csax = sax;
- for (x = 0; x < dst->w; x++) {
- csx += src->w;
- *csax = 0;
- while (csx >= dst->w) {
- csx -= dst->w;
- (*csax)++;
- }
- (*csax) = (*csax) * (flipx ? -1 : 1);
- csax++;
- }
- csy = 0;
- csay = say;
- for (y = 0; y < dst->h; y++) {
- csy += src->h;
- *csay = 0;
- while (csy >= dst->h) {
- csy -= dst->h;
- (*csay)++;
- }
- (*csay) = (*csay) * (flipy ? -1 : 1);
- csay++;
- }
-
- /*
- * 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);
-}
-
-/*!
-\brief Internal 32 bit rotozoomer with optional anti-aliasing.
-
-Rotates and zooms 32 bit RGBA/ABGR 'src' surface to 'dst' surface based on the control
-parameters by scanning the destination surface and applying optionally anti-aliasing
-by bilinear interpolation.
-Assumes src and dst surfaces are of 32 bit depth.
-Assumes dst surface was allocated with the correct dimensions.
-
-\param src Source surface.
-\param dst Destination surface.
-\param cx Horizontal center coordinate.
-\param cy Vertical center coordinate.
-\param isin Integer version of sine of angle.
-\param icos Integer version of cosine of angle.
-\param flipx Flag indicating horizontal mirroring should be applied.
-\param flipy Flag indicating vertical mirroring should be applied.
-\param smooth Flag indicating anti-aliasing should be used.
-*/
-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, cswap;
- 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 = (tColorRGBA*) 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 (flipx) dx = sw - dx;
- if (flipy) dy = sh - dy;
- if ((dx > -1) && (dy > -1) && (dx < (src->w-1)) && (dy < (src->h-1))) {
- sp = (tColorRGBA *)src->pixels;;
- sp += ((src->pitch/4) * dy);
- sp += dx;
- c00 = *sp;
- sp += 1;
- c01 = *sp;
- sp += (src->pitch/4);
- c11 = *sp;
- sp -= 1;
- c10 = *sp;
- if (flipx) {
- cswap = c00; c00=c01; c01=cswap;
- cswap = c10; c10=c11; c11=cswap;
- }
- if (flipy) {
- cswap = c00; c00=c10; c10=cswap;
- cswap = c01; c01=c11; c11=cswap;
- }
- /*
- * 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);
- }
- }
-}
-
-/*!
-
-\brief Rotates and zooms 8 bit palette/Y 'src' surface to 'dst' surface without smoothing.
-
-Rotates and zooms 8 bit RGBA/ABGR 'src' surface to 'dst' surface based on the control
-parameters by scanning the destination surface.
-Assumes src and dst surfaces are of 8 bit depth.
-Assumes dst surface was allocated with the correct dimensions.
-
-\param src Source surface.
-\param dst Destination surface.
-\param cx Horizontal center coordinate.
-\param cy Vertical center coordinate.
-\param isin Integer version of sine of angle.
-\param icos Integer version of cosine of angle.
-\param flipx Flag indicating horizontal mirroring should be applied.
-\param flipy Flag indicating vertical mirroring should be applied.
-*/
-void transformSurfaceY(SDL_Surface * src, SDL_Surface * dst, int cx, int cy, int isin, int icos, int flipx, int flipy)
-{
- 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 = (tColorY*) dst->pixels;
- gap = dst->pitch - dst->w;
- /*
- * Clear surface to colorkey
- */
- memset(pc, (int)(_colorkey(src) & 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 (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 = (tColorY *) (src->pixels);
- sp += (src->pitch * dy + dx);
- *pc = *sp;
- }
- sdx += icos;
- sdy += isin;
- pc++;
- }
- pc += gap;
- }
-}
-
-/*!
-\brief Rotates a 32 bit surface in increments of 90 degrees.
-
-Specialized 90 degree rotator which rotates a 'src' surface in 90 degree
-increments clockwise returning a new surface. Faster than rotozoomer since
-not scanning or interpolation takes place. Input surface must be 32 bit.
-(code contributed by J. Schiller, improved by C. Allport and A. Schiffler)
-
-\param src Source surface to rotate.
-\param numClockwiseTurns Number of clockwise 90 degree turns to apply to the source.
-
-\returns The new, rotated surface; or NULL for surfaces with incorrect input format.
-*/
-SDL_Surface* rotateSurface90Degrees(SDL_Surface* src, int numClockwiseTurns)
-{
- int row, col, newWidth, newHeight;
- int bpp, src_ipr, dst_ipr;
- SDL_Surface* dst;
- Uint32* srcBuf;
- Uint32* dstBuf;
-
- /* Has to be a valid surface pointer and only 32-bit surfaces (for now) */
- if (!src || src->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 */
- newWidth = (numClockwiseTurns % 2) ? (src->h) : (src->w);
- newHeight = (numClockwiseTurns % 2) ? (src->w) : (src->h);
- dst = SDL_CreateRGBSurface( src->flags, newWidth, newHeight, src->format->BitsPerPixel,
- src->format->Rmask,
- src->format->Gmask,
- src->format->Bmask,
- src->format->Amask);
- if(!dst) {
- return NULL;
- }
-
- if (SDL_MUSTLOCK(dst)) {
- SDL_LockSurface(dst);
- }
- if (SDL_MUSTLOCK(dst)) {
- SDL_LockSurface(dst);
- }
-
- /* Calculate int-per-row */
- bpp = src->format->BitsPerPixel / 8;
- src_ipr = src->pitch / bpp;
- dst_ipr = dst->pitch / bpp;
-
- switch(numClockwiseTurns) {
- case 0: /* Make a copy of the surface */
- {
- /* Unfortunately SDL_BlitSurface cannot be used to make a copy of the surface
- since it does not preserve alpha. */
-
- if (src->pitch == dst->pitch) {
- /* If the pitch is the same for both surfaces, the memory can be copied all at once. */
- memcpy(dst->pixels, src->pixels, (src->h * src->pitch));
- }
- else
- {
- /* If the pitch differs, copy each row separately */
- srcBuf = (Uint32*)(src->pixels);
- dstBuf = (Uint32*)(dst->pixels);
- for (row = 0; row < src->h; row++) {
- memcpy(dstBuf, srcBuf, dst->w * bpp);
- srcBuf += src_ipr;
- dstBuf += dst_ipr;
- } /* end for(col) */
- } /* end for(row) */
- }
- break;
-
- /* rotate clockwise */
- case 1: /* rotated 90 degrees clockwise */
- {
- for (row = 0; row < src->h; ++row) {
- srcBuf = (Uint32*)(src->pixels) + (row * src_ipr);
- dstBuf = (Uint32*)(dst->pixels) + (dst->w - row - 1);
- for (col = 0; col < src->w; ++col) {
- *dstBuf = *srcBuf;
- ++srcBuf;
- dstBuf += dst_ipr;
- }
- /* end for(col) */
- }
- /* end for(row) */
- }
- break;
-
- case 2: /* rotated 180 degrees clockwise */
- {
- for (row = 0; row < src->h; ++row) {
- srcBuf = (Uint32*)(src->pixels) + (row * src_ipr);
- dstBuf = (Uint32*)(dst->pixels) + ((dst->h - row - 1) * dst_ipr) + (dst->w - 1);
- for (col = 0; col < src->w; ++col) {
- *dstBuf = *srcBuf;
- ++srcBuf;
- --dstBuf;
- }
- }
- }
- break;
-
- case 3:
- {
- for (row = 0; row < src->h; ++row) {
- srcBuf = (Uint32*)(src->pixels) + (row * src_ipr);
- dstBuf = (Uint32*)(dst->pixels) + row + ((dst->h - 1) * dst_ipr);
- for (col = 0; col < src->w; ++col) {
- *dstBuf = *srcBuf;
- ++srcBuf;
- dstBuf -= dst_ipr;
- }
- }
- }
- break;
- }
- /* end switch */
-
- if (SDL_MUSTLOCK(src)) {
- SDL_UnlockSurface(src);
- }
- if (SDL_MUSTLOCK(dst)) {
- SDL_UnlockSurface(dst);
- }
-
- return dst;
-}
-
-
-/*!
-\brief Internal target surface sizing function for rotozooms with trig result return.
-
-\param width The source surface width.
-\param height The source surface height.
-\param angle The angle to rotate in degrees.
-\param zoomx The horizontal scaling factor.
-\param zoomy The vertical scaling factor.
-\param dstwidth The calculated width of the destination surface.
-\param dstheight The calculated height of the destination surface.
-\param canglezoom The sine of the angle adjusted by the zoom factor.
-\param sanglezoom The cosine of the angle adjusted by the zoom factor.
-
-*/
-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 = (double)(width / 2);
- y = (double)(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;
-}
-
-/*!
-\brief Returns the size of the resulting target surface for a rotozoomSurfaceXY() call.
-
-\param width The source surface width.
-\param height The source surface height.
-\param angle The angle to rotate in degrees.
-\param zoomx The horizontal scaling factor.
-\param zoomy The vertical scaling factor.
-\param dstwidth The calculated width of the rotozoomed destination surface.
-\param dstheight The calculated height of the rotozoomed destination surface.
-*/
-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);
-}
-
-/*!
-\brief Returns the size of the resulting target surface for a rotozoomSurface() call.
-
-\param width The source surface width.
-\param height The source surface height.
-\param angle The angle to rotate in degrees.
-\param zoom The scaling factor.
-\param dstwidth The calculated width of the rotozoomed destination surface.
-\param dstheight The calculated height of the rotozoomed destination surface.
-*/
-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);
-}
-
-/*!
-\brief Rotates and zooms a surface and optional anti-aliasing.
-
-Rotates and zoomes a 32bit or 8bit 'src' surface to newly created 'dst' surface.
-'angle' is the rotation in degrees and 'zoom' a scaling factor. If 'smooth' is set
-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.
-
-\param src The surface to rotozoom.
-\param angle The angle to rotate in degrees.
-\param zoom The scaling factor.
-\param smooth Antialiasing flag; set to SMOOTHING_ON to enable.
-
-\return The new rotozoomed surface.
-*/
-SDL_Surface *rotozoomSurface(SDL_Surface * src, double angle, double zoom, int smooth)
-{
- return rotozoomSurfaceXY(src, angle, zoom, zoom, smooth);
-}
-
-/*!
-\brief Rotates and zooms a surface with different horizontal and vertival scaling factors and optional anti-aliasing.
-
-Rotates and zooms a 32bit or 8bit 'src' surface to newly created 'dst' surface.
-'angle' is the rotation in degrees, 'zoomx and 'zoomy' scaling factors. If 'smooth' is set
-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.
-
-\param src The surface to rotozoom.
-\param angle The angle to rotate in degrees.
-\param zoomx The horizontal scaling factor.
-\param zoomy The vertical scaling factor.
-\param smooth Antialiasing flag; set to SMOOTHING_ON to enable.
-
-\return The new rotozoomed surface.
-*/
-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;
-
- /*
- * 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;
- }
-
- /*
- * Sanity check zoom factor
- */
- flipx = (zoomx<0.0);
- if (flipx) zoomx=-zoomx;
- flipy = (zoomy<0.0);
- 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 + GUARD_ROWS, 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 + GUARD_ROWS, 8, 0, 0, 0, 0);
- }
-
- /* Check target */
- if (rz_dst == NULL)
- return NULL;
-
- /* Adjust for guard rows */
- rz_dst->h = dstheight;
-
- /*
- * Lock source surface
- */
- if (SDL_MUSTLOCK(rz_src)) {
- 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);
- } 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),
- flipx, flipy);
- }
- /*
- * Unlock source surface
- */
- if (SDL_MUSTLOCK(rz_src)) {
- 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 + GUARD_ROWS, 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 + GUARD_ROWS, 8, 0, 0, 0, 0);
- }
-
- /* Check target */
- if (rz_dst == NULL)
- return NULL;
-
- /* Adjust for guard rows */
- rz_dst->h = dstheight;
-
- /*
- * Lock source surface
- */
- if (SDL_MUSTLOCK(rz_src)) {
- 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);
-
- } 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);
- }
-
- /*
- * Unlock source surface
- */
- if (SDL_MUSTLOCK(rz_src)) {
- SDL_UnlockSurface(rz_src);
- }
- }
-
- /*
- * Cleanup temp surface
- */
- if (src_converted) {
- SDL_FreeSurface(rz_src);
- }
-
- /*
- * Return destination surface
- */
- return (rz_dst);
-}
-
-/*!
-\brief Calculates the size of the target surface for a zoomSurface() call.
-
-The minimum size of the target surface is 1. The input factors can be positive or negative.
-
-\param width The width of the source surface to zoom.
-\param height The height of the source surface to zoom.
-\param zoomx The horizontal zoom factor.
-\param zoomy The vertical zoom factor.
-\param dstwidth Pointer to an integer to store the calculated width of the zoomed target surface.
-\param dstheight Pointer to an integer to store the calculated height of the zoomed target surface.
-*/
-void zoomSurfaceSize(int width, int height, double zoomx, double zoomy, int *dstwidth, int *dstheight)
-{
- /*
- * Make zoom factors positive
- */
- int flipx, flipy;
- flipx = (zoomx<0.0);
- if (flipx) zoomx = -zoomx;
- flipy = (zoomy<0.0);
- if (flipy) zoomy = -zoomy;
-
- /*
- * Sanity check zoom factors
- */
- if (zoomx < VALUE_LIMIT) {
- zoomx = VALUE_LIMIT;
- }
- if (zoomy < VALUE_LIMIT) {
- zoomy = VALUE_LIMIT;
- }
-
- /*
- * Calculate target size
- */
- *dstwidth = (int) floor(((double) width * zoomx) + 0.5);
- *dstheight = (int) floor(((double) height * zoomy) + 0.5);
- if (*dstwidth < 1) {
- *dstwidth = 1;
- }
- if (*dstheight < 1) {
- *dstheight = 1;
- }
-}
-
-/*!
-\brief Zoom a surface by independent horizontal and vertical factors with optional smoothing.
-
-Zooms a 32bit or 8bit 'src' surface to newly created 'dst' surface.
-'zoomx' and 'zoomy' are scaling factors for width and height. If 'smooth' is on
-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.
-If zoom factors are negative, the image is flipped on the axes.
-
-\param src The surface to zoom.
-\param zoomx The horizontal zoom factor.
-\param zoomy The vertical zoom factor.
-\param smooth Antialiasing flag; set to SMOOTHING_ON to enable.
-
-\return The new, zoomed surface.
-*/
-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
- );
- if (rz_src == NULL) {
- return NULL;
- }
- SDL_BlitSurface(src, NULL, rz_src, NULL);
- src_converted = 1;
- is32bit = 1;
- }
-
- flipx = (zoomx<0.0);
- if (flipx) zoomx = -zoomx;
- flipy = (zoomy<0.0);
- 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 + GUARD_ROWS, 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 + GUARD_ROWS, 8, 0, 0, 0, 0);
- }
-
- /* Check target */
- if (rz_dst == NULL) {
- /*
- * Cleanup temp surface
- */
- if (src_converted) {
- SDL_FreeSurface(rz_src);
- }
- return NULL;
- }
-
- /* Adjust for guard rows */
- rz_dst->h = dstheight;
-
- /*
- * Lock source surface
- */
- if (SDL_MUSTLOCK(rz_src)) {
- 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);
- } 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);
- }
- /*
- * Unlock source surface
- */
- if (SDL_MUSTLOCK(rz_src)) {
- SDL_UnlockSurface(rz_src);
- }
-
- /*
- * Cleanup temp surface
- */
- if (src_converted) {
- SDL_FreeSurface(rz_src);
- }
-
- /*
- * Return destination surface
- */
- return (rz_dst);
-}
-
-/*!
-\brief Shrink a surface by an integer ratio using averaging.
-
-Shrinks a 32bit or 8bit 'src' surface to a newly created 'dst' surface.
-'factorx' and 'factory' are the shrinking ratios (i.e. 2=1/2 the size,
-3=1/3 the size, etc.) The destination surface is antialiased by averaging
-the source box RGBA or Y information. If the surface is not 8bit
-or 32bit RGBA/ABGR it will be converted into a 32bit RGBA format on the fly.
-The input surface is not modified. The output surface is newly allocated.
-
-\param src The surface to shrink.
-\param factorx The horizontal shrinking ratio.
-\param factory The vertical shrinking ratio.
-
-\return The new, shrunken surface.
-*/
-/*@null@*/
-SDL_Surface *shrinkSurface(SDL_Surface *src, int factorx, int factory)
-{
- int result;
- SDL_Surface *rz_src;
- SDL_Surface *rz_dst = NULL;
- int dstwidth, dstheight;
- int is32bit;
- int i, src_converted;
- int haveError = 0;
-
- /*
- * 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
- );
- if (rz_src==NULL) {
- haveError = 1;
- goto exitShrinkSurface;
- }
-
- SDL_BlitSurface(src, NULL, rz_src, NULL);
- src_converted = 1;
- is32bit = 1;
- }
-
- /*
- * Lock the surface
- */
- if (SDL_MUSTLOCK(rz_src)) {
- if (SDL_LockSurface(rz_src) < 0) {
- haveError = 1;
- goto exitShrinkSurface;
- }
- }
-
- /* 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
- * (with added guard rows)
- */
- if (is32bit==1) {
- /*
- * Target surface is 32bit with source RGBA/ABGR ordering
- */
- rz_dst =
- SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight + GUARD_ROWS, 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 + GUARD_ROWS, 8, 0, 0, 0, 0);
- }
-
- /* Check target */
- if (rz_dst == NULL) {
- haveError = 1;
- goto exitShrinkSurface;
- }
-
- /* Adjust for guard rows */
- rz_dst->h = dstheight;
-
- /*
- * Check which kind of surface we have
- */
- if (is32bit==1) {
- /*
- * Call the 32bit transformation routine to do the shrinking (using alpha)
- */
- result = _shrinkSurfaceRGBA(rz_src, rz_dst, factorx, factory);
- if ((result!=0) || (rz_dst==NULL)) {
- haveError = 1;
- goto exitShrinkSurface;
- }
- } 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
- */
- result = _shrinkSurfaceY(rz_src, rz_dst, factorx, factory);
- if (result!=0) {
- haveError = 1;
- goto exitShrinkSurface;
- }
- }
-
-exitShrinkSurface:
- if (rz_src!=NULL) {
- /*
- * Unlock source surface
- */
- if (SDL_MUSTLOCK(rz_src)) {
- SDL_UnlockSurface(rz_src);
- }
-
- /*
- * Cleanup temp surface
- */
- if (src_converted==1) {
- SDL_FreeSurface(rz_src);
- }
- }
-
- /* Check error state; maybe need to cleanup destination */
- if (haveError==1) {
- if (rz_dst!=NULL) {
- SDL_FreeSurface(rz_dst);
- }
- rz_dst=NULL;
- }
-
- /*
- * Return destination surface
- */
- return (rz_dst);
-}