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SDL_surface.c
932 lines (851 loc) · 27 KB
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/*
SDL - Simple DirectMedia Layer
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Copyright (C) 1997-2006 Sam Lantinga
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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Sam Lantinga
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slouken@libsdl.org
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*/
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#include "SDL_config.h"
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#include "SDL_video.h"
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#include "SDL_sysvideo.h"
#include "SDL_cursor_c.h"
#include "SDL_blit.h"
#include "SDL_RLEaccel_c.h"
#include "SDL_pixels_c.h"
#include "SDL_leaks.h"
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/* Public routines */
/*
* Create an empty RGB surface of the appropriate depth
*/
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SDL_Surface *
SDL_CreateRGBSurface (Uint32 flags,
int width, int height, int depth,
Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask)
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{
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SDL_VideoDevice *_this = SDL_GetVideoDevice ();
SDL_Surface *screen;
SDL_Surface *surface;
/* Make sure the size requested doesn't overflow our datatypes */
/* Next time I write a library like SDL, I'll use int for size. :) */
if (width >= 16384 || height >= 65536) {
SDL_SetError ("Width or height is too large");
return (NULL);
}
/* Check to see if we desire the surface in video memory */
if (_this) {
screen = SDL_PublicSurface;
} else {
screen = NULL;
}
if (screen && ((screen->flags & SDL_HWSURFACE) == SDL_HWSURFACE)) {
if ((flags & (SDL_SRCCOLORKEY | SDL_SRCALPHA)) != 0) {
flags |= SDL_HWSURFACE;
}
if ((flags & SDL_SRCCOLORKEY) == SDL_SRCCOLORKEY) {
if (!_this->info.blit_hw_CC) {
flags &= ~SDL_HWSURFACE;
}
}
if ((flags & SDL_SRCALPHA) == SDL_SRCALPHA) {
if (!_this->info.blit_hw_A) {
flags &= ~SDL_HWSURFACE;
}
}
} else {
flags &= ~SDL_HWSURFACE;
}
/* Allocate the surface */
surface = (SDL_Surface *) SDL_malloc (sizeof (*surface));
if (surface == NULL) {
SDL_OutOfMemory ();
return (NULL);
}
surface->flags = SDL_SWSURFACE;
if ((flags & SDL_HWSURFACE) == SDL_HWSURFACE) {
if ((Amask) && (_this->displayformatalphapixel)) {
depth = _this->displayformatalphapixel->BitsPerPixel;
Rmask = _this->displayformatalphapixel->Rmask;
Gmask = _this->displayformatalphapixel->Gmask;
Bmask = _this->displayformatalphapixel->Bmask;
Amask = _this->displayformatalphapixel->Amask;
} else {
depth = screen->format->BitsPerPixel;
Rmask = screen->format->Rmask;
Gmask = screen->format->Gmask;
Bmask = screen->format->Bmask;
Amask = screen->format->Amask;
}
}
surface->format = SDL_AllocFormat (depth, Rmask, Gmask, Bmask, Amask);
if (surface->format == NULL) {
SDL_free (surface);
return (NULL);
}
if (Amask) {
surface->flags |= SDL_SRCALPHA;
}
surface->w = width;
surface->h = height;
surface->pitch = SDL_CalculatePitch (surface);
surface->pixels = NULL;
surface->offset = 0;
surface->hwdata = NULL;
surface->locked = 0;
surface->map = NULL;
surface->unused1 = 0;
SDL_SetClipRect (surface, NULL);
SDL_FormatChanged (surface);
/* Get the pixels */
if (((flags & SDL_HWSURFACE) == SDL_SWSURFACE) ||
(_this->AllocHWSurface (_this, surface) < 0)) {
if (surface->w && surface->h) {
surface->pixels = SDL_malloc (surface->h * surface->pitch);
if (surface->pixels == NULL) {
SDL_FreeSurface (surface);
SDL_OutOfMemory ();
return (NULL);
}
/* This is important for bitmaps */
SDL_memset (surface->pixels, 0, surface->h * surface->pitch);
}
}
/* Allocate an empty mapping */
surface->map = SDL_AllocBlitMap ();
if (surface->map == NULL) {
SDL_FreeSurface (surface);
return (NULL);
}
/* The surface is ready to go */
surface->refcount = 1;
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#ifdef CHECK_LEAKS
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++surfaces_allocated;
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#endif
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return (surface);
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}
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/*
* Create an RGB surface from an existing memory buffer
*/
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SDL_Surface *
SDL_CreateRGBSurfaceFrom (void *pixels,
int width, int height, int depth, int pitch,
Uint32 Rmask, Uint32 Gmask, Uint32 Bmask,
Uint32 Amask)
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{
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SDL_Surface *surface;
surface = SDL_CreateRGBSurface (SDL_SWSURFACE, 0, 0, depth,
Rmask, Gmask, Bmask, Amask);
if (surface != NULL) {
surface->flags |= SDL_PREALLOC;
surface->pixels = pixels;
surface->w = width;
surface->h = height;
surface->pitch = pitch;
SDL_SetClipRect (surface, NULL);
}
return (surface);
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}
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/*
* Set the color key in a blittable surface
*/
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int
SDL_SetColorKey (SDL_Surface * surface, Uint32 flag, Uint32 key)
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{
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/* Sanity check the flag as it gets passed in */
if (flag & SDL_SRCCOLORKEY) {
if (flag & (SDL_RLEACCEL | SDL_RLEACCELOK)) {
flag = (SDL_SRCCOLORKEY | SDL_RLEACCELOK);
} else {
flag = SDL_SRCCOLORKEY;
}
} else {
flag = 0;
}
/* Optimize away operations that don't change anything */
if ((flag == (surface->flags & (SDL_SRCCOLORKEY | SDL_RLEACCELOK))) &&
(key == surface->format->colorkey)) {
return (0);
}
/* UnRLE surfaces before we change the colorkey */
if (surface->flags & SDL_RLEACCEL) {
SDL_UnRLESurface (surface, 1);
}
if (flag) {
SDL_VideoDevice *_this = SDL_GetVideoDevice ();
surface->flags |= SDL_SRCCOLORKEY;
surface->format->colorkey = key;
if ((surface->flags & SDL_HWACCEL) == SDL_HWACCEL) {
if ((_this->SetHWColorKey == NULL) ||
(_this->SetHWColorKey (_this, surface, key) < 0)) {
surface->flags &= ~SDL_HWACCEL;
}
}
if (flag & SDL_RLEACCELOK) {
surface->flags |= SDL_RLEACCELOK;
} else {
surface->flags &= ~SDL_RLEACCELOK;
}
} else {
surface->flags &= ~(SDL_SRCCOLORKEY | SDL_RLEACCELOK);
surface->format->colorkey = 0;
}
SDL_InvalidateMap (surface->map);
return (0);
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}
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/* This function sets the alpha channel of a surface */
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int
SDL_SetAlpha (SDL_Surface * surface, Uint32 flag, Uint8 value)
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{
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Uint32 oldflags = surface->flags;
Uint32 oldalpha = surface->format->alpha;
/* Sanity check the flag as it gets passed in */
if (flag & SDL_SRCALPHA) {
if (flag & (SDL_RLEACCEL | SDL_RLEACCELOK)) {
flag = (SDL_SRCALPHA | SDL_RLEACCELOK);
} else {
flag = SDL_SRCALPHA;
}
} else {
flag = 0;
}
/* Optimize away operations that don't change anything */
if ((flag == (surface->flags & (SDL_SRCALPHA | SDL_RLEACCELOK))) &&
(!flag || value == oldalpha)) {
return (0);
}
if (!(flag & SDL_RLEACCELOK) && (surface->flags & SDL_RLEACCEL))
SDL_UnRLESurface (surface, 1);
if (flag) {
SDL_VideoDevice *_this = SDL_GetVideoDevice ();
surface->flags |= SDL_SRCALPHA;
surface->format->alpha = value;
if ((surface->flags & SDL_HWACCEL) == SDL_HWACCEL) {
if ((_this->SetHWAlpha == NULL) ||
(_this->SetHWAlpha (_this, surface, value) < 0)) {
surface->flags &= ~SDL_HWACCEL;
}
}
if (flag & SDL_RLEACCELOK) {
surface->flags |= SDL_RLEACCELOK;
} else {
surface->flags &= ~SDL_RLEACCELOK;
}
} else {
surface->flags &= ~SDL_SRCALPHA;
surface->format->alpha = SDL_ALPHA_OPAQUE;
}
/*
* The representation for software surfaces is independent of
* per-surface alpha, so no need to invalidate the blit mapping
* if just the alpha value was changed. (If either is 255, we still
* need to invalidate.)
*/
if ((surface->flags & SDL_HWACCEL) == SDL_HWACCEL
|| oldflags != surface->flags
|| (((oldalpha + 1) ^ (value + 1)) & 0x100))
SDL_InvalidateMap (surface->map);
return (0);
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}
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int
SDL_SetAlphaChannel (SDL_Surface * surface, Uint8 value)
{
int row, col;
int offset;
Uint8 *buf;
if ((surface->format->Amask != 0xFF000000) &&
(surface->format->Amask != 0x000000FF)) {
SDL_SetError ("Unsupported surface alpha mask format");
return -1;
}
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#if SDL_BYTEORDER == SDL_LIL_ENDIAN
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if (surface->format->Amask == 0xFF000000) {
offset = 3;
} else {
offset = 0;
}
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#else
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if (surface->format->Amask == 0xFF000000) {
offset = 0;
} else {
offset = 3;
}
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#endif /* Byte ordering */
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/* Quickly set the alpha channel of an RGBA or ARGB surface */
if (SDL_MUSTLOCK (surface)) {
if (SDL_LockSurface (surface) < 0) {
return -1;
}
}
row = surface->h;
while (row--) {
col = surface->w;
buf = (Uint8 *) surface->pixels + row * surface->pitch + offset;
while (col--) {
*buf = value;
buf += 4;
}
}
if (SDL_MUSTLOCK (surface)) {
SDL_UnlockSurface (surface);
}
return 0;
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}
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/*
* A function to calculate the intersection of two rectangles:
* return true if the rectangles intersect, false otherwise
*/
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static __inline__ SDL_bool
SDL_IntersectRect (const SDL_Rect * A, const SDL_Rect * B,
SDL_Rect * intersection)
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{
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int Amin, Amax, Bmin, Bmax;
/* Horizontal intersection */
Amin = A->x;
Amax = Amin + A->w;
Bmin = B->x;
Bmax = Bmin + B->w;
if (Bmin > Amin)
Amin = Bmin;
intersection->x = Amin;
if (Bmax < Amax)
Amax = Bmax;
intersection->w = Amax - Amin > 0 ? Amax - Amin : 0;
/* Vertical intersection */
Amin = A->y;
Amax = Amin + A->h;
Bmin = B->y;
Bmax = Bmin + B->h;
if (Bmin > Amin)
Amin = Bmin;
intersection->y = Amin;
if (Bmax < Amax)
Amax = Bmax;
intersection->h = Amax - Amin > 0 ? Amax - Amin : 0;
return (intersection->w && intersection->h);
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}
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/*
* Set the clipping rectangle for a blittable surface
*/
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SDL_bool
SDL_SetClipRect (SDL_Surface * surface, const SDL_Rect * rect)
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{
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SDL_Rect full_rect;
/* Don't do anything if there's no surface to act on */
if (!surface) {
return SDL_FALSE;
}
/* Set up the full surface rectangle */
full_rect.x = 0;
full_rect.y = 0;
full_rect.w = surface->w;
full_rect.h = surface->h;
/* Set the clipping rectangle */
if (!rect) {
surface->clip_rect = full_rect;
return 1;
}
return SDL_IntersectRect (rect, &full_rect, &surface->clip_rect);
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}
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void
SDL_GetClipRect (SDL_Surface * surface, SDL_Rect * rect)
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{
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if (surface && rect) {
*rect = surface->clip_rect;
}
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}
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/*
* Set up a blit between two surfaces -- split into three parts:
* The upper part, SDL_UpperBlit(), performs clipping and rectangle
* verification. The lower part is a pointer to a low level
* accelerated blitting function.
*
* These parts are separated out and each used internally by this
* library in the optimimum places. They are exported so that if
* you know exactly what you are doing, you can optimize your code
* by calling the one(s) you need.
*/
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int
SDL_LowerBlit (SDL_Surface * src, SDL_Rect * srcrect,
SDL_Surface * dst, SDL_Rect * dstrect)
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{
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SDL_blit do_blit;
/* Check to make sure the blit mapping is valid */
if ((src->map->dst != dst) ||
(src->map->dst->format_version != src->map->format_version)) {
if (SDL_MapSurface (src, dst) < 0) {
return (-1);
}
}
/* Figure out which blitter to use */
if ((src->flags & SDL_HWACCEL) == SDL_HWACCEL) {
do_blit = src->map->hw_blit;
} else {
do_blit = src->map->sw_blit;
}
return (do_blit (src, srcrect, dst, dstrect));
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}
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int
SDL_UpperBlit (SDL_Surface * src, SDL_Rect * srcrect,
SDL_Surface * dst, SDL_Rect * dstrect)
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{
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SDL_Rect fulldst;
int srcx, srcy, w, h;
/* Make sure the surfaces aren't locked */
if (!src || !dst) {
SDL_SetError ("SDL_UpperBlit: passed a NULL surface");
return (-1);
}
if (src->locked || dst->locked) {
SDL_SetError ("Surfaces must not be locked during blit");
return (-1);
}
/* If the destination rectangle is NULL, use the entire dest surface */
if (dstrect == NULL) {
fulldst.x = fulldst.y = 0;
dstrect = &fulldst;
}
/* clip the source rectangle to the source surface */
if (srcrect) {
int maxw, maxh;
srcx = srcrect->x;
w = srcrect->w;
if (srcx < 0) {
w += srcx;
dstrect->x -= srcx;
srcx = 0;
}
maxw = src->w - srcx;
if (maxw < w)
w = maxw;
srcy = srcrect->y;
h = srcrect->h;
if (srcy < 0) {
h += srcy;
dstrect->y -= srcy;
srcy = 0;
}
maxh = src->h - srcy;
if (maxh < h)
h = maxh;
} else {
srcx = srcy = 0;
w = src->w;
h = src->h;
}
/* clip the destination rectangle against the clip rectangle */
{
SDL_Rect *clip = &dst->clip_rect;
int dx, dy;
dx = clip->x - dstrect->x;
if (dx > 0) {
w -= dx;
dstrect->x += dx;
srcx += dx;
}
dx = dstrect->x + w - clip->x - clip->w;
if (dx > 0)
w -= dx;
dy = clip->y - dstrect->y;
if (dy > 0) {
h -= dy;
dstrect->y += dy;
srcy += dy;
}
dy = dstrect->y + h - clip->y - clip->h;
if (dy > 0)
h -= dy;
}
if (w > 0 && h > 0) {
SDL_Rect sr;
sr.x = srcx;
sr.y = srcy;
sr.w = dstrect->w = w;
sr.h = dstrect->h = h;
return SDL_LowerBlit (src, &sr, dst, dstrect);
}
dstrect->w = dstrect->h = 0;
return 0;
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}
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static int
SDL_FillRect1 (SDL_Surface * dst, SDL_Rect * dstrect, Uint32 color)
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{
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/* FIXME: We have to worry about packing order.. *sigh* */
SDL_SetError ("1-bpp rect fill not yet implemented");
return -1;
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}
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static int
SDL_FillRect4 (SDL_Surface * dst, SDL_Rect * dstrect, Uint32 color)
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{
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/* FIXME: We have to worry about packing order.. *sigh* */
SDL_SetError ("4-bpp rect fill not yet implemented");
return -1;
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}
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/*
* This function performs a fast fill of the given rectangle with 'color'
*/
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int
SDL_FillRect (SDL_Surface * dst, SDL_Rect * dstrect, Uint32 color)
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{
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SDL_VideoDevice *_this = SDL_GetVideoDevice ();
int x, y;
Uint8 *row;
/* This function doesn't work on surfaces < 8 bpp */
if (dst->format->BitsPerPixel < 8) {
switch (dst->format->BitsPerPixel) {
case 1:
return SDL_FillRect1 (dst, dstrect, color);
break;
case 4:
return SDL_FillRect4 (dst, dstrect, color);
break;
default:
SDL_SetError ("Fill rect on unsupported surface format");
return (-1);
break;
}
}
/* If 'dstrect' == NULL, then fill the whole surface */
if (dstrect) {
/* Perform clipping */
if (!SDL_IntersectRect (dstrect, &dst->clip_rect, dstrect)) {
return (0);
}
} else {
dstrect = &dst->clip_rect;
}
/* Check for hardware acceleration */
if (((dst->flags & SDL_HWSURFACE) == SDL_HWSURFACE) &&
_this->info.blit_fill) {
return (_this->FillHWRect (_this, dst, dstrect, color));
}
/* Perform software fill */
if (SDL_LockSurface (dst) != 0) {
return (-1);
}
row = (Uint8 *) dst->pixels + dstrect->y * dst->pitch +
dstrect->x * dst->format->BytesPerPixel;
if (dst->format->palette || (color == 0)) {
x = dstrect->w * dst->format->BytesPerPixel;
if (!color && !((uintptr_t) row & 3) && !(x & 3)
&& !(dst->pitch & 3)) {
int n = x >> 2;
for (y = dstrect->h; y; --y) {
SDL_memset4 (row, 0, n);
row += dst->pitch;
}
} else {
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#ifdef __powerpc__
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/*
* SDL_memset() on PPC (both glibc and codewarrior) uses
* the dcbz (Data Cache Block Zero) instruction, which
* causes an alignment exception if the destination is
* uncachable, so only use it on software surfaces
*/
if ((dst->flags & SDL_HWSURFACE) == SDL_HWSURFACE) {
if (dstrect->w >= 8) {
/*
* 64-bit stores are probably most
* efficient to uncached video memory
*/
double fill;
SDL_memset (&fill, color, (sizeof fill));
for (y = dstrect->h; y; y--) {
Uint8 *d = row;
unsigned n = x;
unsigned nn;
Uint8 c = color;
double f = fill;
while ((unsigned long) d & (sizeof (double) - 1)) {
*d++ = c;
n--;
}
nn = n / (sizeof (double) * 4);
while (nn) {
((double *) d)[0] = f;
((double *) d)[1] = f;
((double *) d)[2] = f;
((double *) d)[3] = f;
d += 4 * sizeof (double);
nn--;
}
n &= ~(sizeof (double) * 4 - 1);
nn = n / sizeof (double);
while (nn) {
*(double *) d = f;
d += sizeof (double);
nn--;
}
n &= ~(sizeof (double) - 1);
while (n) {
*d++ = c;
n--;
}
row += dst->pitch;
}
} else {
/* narrow boxes */
for (y = dstrect->h; y; y--) {
Uint8 *d = row;
Uint8 c = color;
int n = x;
while (n) {
*d++ = c;
n--;
}
row += dst->pitch;
}
}
} else
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#endif /* __powerpc__ */
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{
for (y = dstrect->h; y; y--) {
SDL_memset (row, color, x);
row += dst->pitch;
}
}
}
} else {
switch (dst->format->BytesPerPixel) {
case 2:
for (y = dstrect->h; y; --y) {
Uint16 *pixels = (Uint16 *) row;
Uint16 c = (Uint16) color;
Uint32 cc = (Uint32) c << 16 | c;
int n = dstrect->w;
if ((uintptr_t) pixels & 3) {
*pixels++ = c;
n--;
}
if (n >> 1)
SDL_memset4 (pixels, cc, n >> 1);
if (n & 1)
pixels[n - 1] = c;
row += dst->pitch;
}
break;
case 3:
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
color <<= 8;
#endif
for (y = dstrect->h; y; --y) {
Uint8 *pixels = row;
for (x = dstrect->w; x; --x) {
SDL_memcpy (pixels, &color, 3);
pixels += 3;
}
row += dst->pitch;
}
break;
case 4:
for (y = dstrect->h; y; --y) {
SDL_memset4 (row, color, dstrect->w);
row += dst->pitch;
}
break;
}
}
SDL_UnlockSurface (dst);
/* We're done! */
return (0);
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}
/*
* Lock a surface to directly access the pixels
*/
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int
SDL_LockSurface (SDL_Surface * surface)
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{
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if (!surface->locked) {
/* Perform the lock */
if (surface->flags & SDL_HWSURFACE) {
SDL_VideoDevice *_this = SDL_GetVideoDevice ();
if (_this->LockHWSurface (_this, surface) < 0) {
return (-1);
}
}
if (surface->flags & SDL_RLEACCEL) {
SDL_UnRLESurface (surface, 1);
surface->flags |= SDL_RLEACCEL; /* save accel'd state */
}
/* This needs to be done here in case pixels changes value */
surface->pixels = (Uint8 *) surface->pixels + surface->offset;
}
/* Increment the surface lock count, for recursive locks */
++surface->locked;
/* Ready to go.. */
return (0);
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}
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/*
* Unlock a previously locked surface
*/
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void
SDL_UnlockSurface (SDL_Surface * surface)
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{
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/* Only perform an unlock if we are locked */
if (!surface->locked || (--surface->locked > 0)) {
return;
}
/* Perform the unlock */
surface->pixels = (Uint8 *) surface->pixels - surface->offset;
/* Unlock hardware or accelerated surfaces */
if (surface->flags & SDL_HWSURFACE) {
SDL_VideoDevice *_this = SDL_GetVideoDevice ();
_this->UnlockHWSurface (_this, surface);
} else {
/* Update RLE encoded surface with new data */
if ((surface->flags & SDL_RLEACCEL) == SDL_RLEACCEL) {
surface->flags &= ~SDL_RLEACCEL; /* stop lying */
SDL_RLESurface (surface);
}
}
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}
/*
* Convert a surface into the specified pixel format.
*/
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SDL_Surface *
SDL_ConvertSurface (SDL_Surface * surface,
SDL_PixelFormat * format, Uint32 flags)
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{
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SDL_Surface *convert;
Uint32 colorkey = 0;
Uint8 alpha = 0;
Uint32 surface_flags;
SDL_Rect bounds;
/* Check for empty destination palette! (results in empty image) */
if (format->palette != NULL) {
int i;
for (i = 0; i < format->palette->ncolors; ++i) {
if ((format->palette->colors[i].r != 0) ||
(format->palette->colors[i].g != 0) ||
(format->palette->colors[i].b != 0))
break;
}
if (i == format->palette->ncolors) {
SDL_SetError ("Empty destination palette");
return (NULL);
}
}
/* Only create hw surfaces with alpha channel if hw alpha blits
are supported */
if (format->Amask != 0 && (flags & SDL_HWSURFACE)) {
const SDL_VideoInfo *vi = SDL_GetVideoInfo ();
if (!vi || !vi->blit_hw_A)
flags &= ~SDL_HWSURFACE;
}
/* Create a new surface with the desired format */
convert = SDL_CreateRGBSurface (flags,
surface->w, surface->h,
format->BitsPerPixel, format->Rmask,
format->Gmask, format->Bmask,
format->Amask);
if (convert == NULL) {
return (NULL);
}
/* Copy the palette if any */
if (format->palette && convert->format->palette) {
SDL_memcpy (convert->format->palette->colors,
format->palette->colors,
format->palette->ncolors * sizeof (SDL_Color));
convert->format->palette->ncolors = format->palette->ncolors;
}
/* Save the original surface color key and alpha */
surface_flags = surface->flags;
if ((surface_flags & SDL_SRCCOLORKEY) == SDL_SRCCOLORKEY) {
/* Convert colourkeyed surfaces to RGBA if requested */
if ((flags & SDL_SRCCOLORKEY) != SDL_SRCCOLORKEY && format->Amask) {
surface_flags &= ~SDL_SRCCOLORKEY;
} else {
colorkey = surface->format->colorkey;
SDL_SetColorKey (surface, 0, 0);
}
}
if ((surface_flags & SDL_SRCALPHA) == SDL_SRCALPHA) {
/* Copy over the alpha channel to RGBA if requested */
if (format->Amask) {
surface->flags &= ~SDL_SRCALPHA;
} else {
alpha = surface->format->alpha;
SDL_SetAlpha (surface, 0, 0);
}
}
/* Copy over the image data */
bounds.x = 0;
bounds.y = 0;
bounds.w = surface->w;
bounds.h = surface->h;
SDL_LowerBlit (surface, &bounds, convert, &bounds);
/* Clean up the original surface, and update converted surface */
if (convert != NULL) {
SDL_SetClipRect (convert, &surface->clip_rect);
}
if ((surface_flags & SDL_SRCCOLORKEY) == SDL_SRCCOLORKEY) {
Uint32 cflags = surface_flags & (SDL_SRCCOLORKEY | SDL_RLEACCELOK);
if (convert != NULL) {
Uint8 keyR, keyG, keyB;
SDL_GetRGB (colorkey, surface->format, &keyR, &keyG, &keyB);
SDL_SetColorKey (convert, cflags | (flags & SDL_RLEACCELOK),
SDL_MapRGB (convert->format, keyR, keyG, keyB));
}
SDL_SetColorKey (surface, cflags, colorkey);
}
if ((surface_flags & SDL_SRCALPHA) == SDL_SRCALPHA) {
Uint32 aflags = surface_flags & (SDL_SRCALPHA | SDL_RLEACCELOK);
if (convert != NULL) {
SDL_SetAlpha (convert, aflags | (flags & SDL_RLEACCELOK), alpha);
}
if (format->Amask) {
surface->flags |= SDL_SRCALPHA;
} else {
SDL_SetAlpha (surface, aflags, alpha);
}
}
/* We're ready to go! */
return (convert);
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}
/*
* Free a surface created by the above function.
*/
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void
SDL_FreeSurface (SDL_Surface * surface)
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{
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if (surface == NULL) {
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return;
}
if (--surface->refcount > 0) {
return;
}
while (surface->locked > 0) {
SDL_UnlockSurface (surface);
}
if ((surface->flags & SDL_RLEACCEL) == SDL_RLEACCEL) {
SDL_UnRLESurface (surface, 0);
}
if (surface->format) {
SDL_FreeFormat (surface->format);
surface->format = NULL;
}
if (surface->map != NULL) {
SDL_FreeBlitMap (surface->map);
surface->map = NULL;
}
if (surface->hwdata) {
SDL_VideoDevice *_this = SDL_GetVideoDevice ();
_this->FreeHWSurface (_this, surface);
}
if (surface->pixels && ((surface->flags & SDL_PREALLOC) != SDL_PREALLOC)) {
SDL_free (surface->pixels);
}
SDL_free (surface);
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#ifdef CHECK_LEAKS
928
--surfaces_allocated;
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#endif
}
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/* vi: set ts=4 sw=4 expandtab: */