SDL  2.0
SDL_blit.c
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 #include "../SDL_internal.h"
22 
23 #include "SDL_video.h"
24 #include "SDL_sysvideo.h"
25 #include "SDL_blit.h"
26 #include "SDL_blit_auto.h"
27 #include "SDL_blit_copy.h"
28 #include "SDL_blit_slow.h"
29 #include "SDL_RLEaccel_c.h"
30 #include "SDL_pixels_c.h"
31 
32 /* The general purpose software blit routine */
33 static int SDLCALL
35  SDL_Surface * dst, SDL_Rect * dstrect)
36 {
37  int okay;
38  int src_locked;
39  int dst_locked;
40 
41  /* Everything is okay at the beginning... */
42  okay = 1;
43 
44  /* Lock the destination if it's in hardware */
45  dst_locked = 0;
46  if (SDL_MUSTLOCK(dst)) {
47  if (SDL_LockSurface(dst) < 0) {
48  okay = 0;
49  } else {
50  dst_locked = 1;
51  }
52  }
53  /* Lock the source if it's in hardware */
54  src_locked = 0;
55  if (SDL_MUSTLOCK(src)) {
56  if (SDL_LockSurface(src) < 0) {
57  okay = 0;
58  } else {
59  src_locked = 1;
60  }
61  }
62 
63  /* Set up source and destination buffer pointers, and BLIT! */
64  if (okay && !SDL_RectEmpty(srcrect)) {
65  SDL_BlitFunc RunBlit;
66  SDL_BlitInfo *info = &src->map->info;
67 
68  /* Set up the blit information */
69  info->src = (Uint8 *) src->pixels +
70  (Uint16) srcrect->y * src->pitch +
71  (Uint16) srcrect->x * info->src_fmt->BytesPerPixel;
72  info->src_w = srcrect->w;
73  info->src_h = srcrect->h;
74  info->src_pitch = src->pitch;
75  info->src_skip =
76  info->src_pitch - info->src_w * info->src_fmt->BytesPerPixel;
77  info->dst =
78  (Uint8 *) dst->pixels + (Uint16) dstrect->y * dst->pitch +
79  (Uint16) dstrect->x * info->dst_fmt->BytesPerPixel;
80  info->dst_w = dstrect->w;
81  info->dst_h = dstrect->h;
82  info->dst_pitch = dst->pitch;
83  info->dst_skip =
84  info->dst_pitch - info->dst_w * info->dst_fmt->BytesPerPixel;
85  RunBlit = (SDL_BlitFunc) src->map->data;
86 
87  /* Run the actual software blit */
88  RunBlit(info);
89  }
90 
91  /* We need to unlock the surfaces if they're locked */
92  if (dst_locked) {
94  }
95  if (src_locked) {
97  }
98  /* Blit is done! */
99  return (okay ? 0 : -1);
100 }
101 
102 #if SDL_HAVE_BLIT_AUTO
103 
104 #ifdef __MACOSX__
105 #include <sys/sysctl.h>
106 
107 static SDL_bool
109 {
110  const char key[] = "hw.l3cachesize";
111  u_int64_t result = 0;
112  size_t typeSize = sizeof(result);
113 
114  if (sysctlbyname(key, &result, &typeSize, NULL, 0) == 0 && result > 0) {
115  return SDL_TRUE;
116  } else {
117  return SDL_FALSE;
118  }
119 }
120 #else
121 static SDL_bool
123 {
124  /* Just guess G4 */
125  return SDL_TRUE;
126 }
127 #endif /* __MACOSX__ */
128 
129 static SDL_BlitFunc
130 SDL_ChooseBlitFunc(Uint32 src_format, Uint32 dst_format, int flags,
131  SDL_BlitFuncEntry * entries)
132 {
134  static int features = 0x7fffffff;
135 
136  /* Get the available CPU features */
137  if (features == 0x7fffffff) {
138  const char *override = SDL_getenv("SDL_BLIT_CPU_FEATURES");
139 
140  features = SDL_CPU_ANY;
141 
142  /* Allow an override for testing .. */
143  if (override) {
144  SDL_sscanf(override, "%u", &features);
145  } else {
146  if (SDL_HasMMX()) {
147  features |= SDL_CPU_MMX;
148  }
149  if (SDL_Has3DNow()) {
150  features |= SDL_CPU_3DNOW;
151  }
152  if (SDL_HasSSE()) {
153  features |= SDL_CPU_SSE;
154  }
155  if (SDL_HasSSE2()) {
156  features |= SDL_CPU_SSE2;
157  }
158  if (SDL_HasAltiVec()) {
159  if (SDL_UseAltivecPrefetch()) {
160  features |= SDL_CPU_ALTIVEC_PREFETCH;
161  } else {
162  features |= SDL_CPU_ALTIVEC_NOPREFETCH;
163  }
164  }
165  }
166  }
167 
168  for (i = 0; entries[i].func; ++i) {
169  /* Check for matching pixel formats */
170  if (src_format != entries[i].src_format) {
171  continue;
172  }
173  if (dst_format != entries[i].dst_format) {
174  continue;
175  }
176 
177  /* Check flags */
178  if ((flagcheck & entries[i].flags) != flagcheck) {
179  continue;
180  }
181 
182  /* Check CPU features */
183  if ((entries[i].cpu & features) != entries[i].cpu) {
184  continue;
185  }
186 
187  /* We found the best one! */
188  return entries[i].func;
189  }
190  return NULL;
191 }
192 #endif /* SDL_HAVE_BLIT_AUTO */
193 
194 /* Figure out which of many blit routines to set up on a surface */
195 int
197 {
198  SDL_BlitFunc blit = NULL;
199  SDL_BlitMap *map = surface->map;
200  SDL_Surface *dst = map->dst;
201 
202  /* We don't currently support blitting to < 8 bpp surfaces */
203  if (dst->format->BitsPerPixel < 8) {
205  return SDL_SetError("Blit combination not supported");
206  }
207 
208 #if SDL_HAVE_RLE
209  /* Clean everything out to start */
210  if ((surface->flags & SDL_RLEACCEL) == SDL_RLEACCEL) {
212  }
213 #endif
214 
215  map->blit = SDL_SoftBlit;
216  map->info.src_fmt = surface->format;
217  map->info.src_pitch = surface->pitch;
218  map->info.dst_fmt = dst->format;
219  map->info.dst_pitch = dst->pitch;
220 
221 #if SDL_HAVE_RLE
222  /* See if we can do RLE acceleration */
223  if (map->info.flags & SDL_COPY_RLE_DESIRED) {
224  if (SDL_RLESurface(surface) == 0) {
225  return 0;
226  }
227  }
228 #endif
229 
230  /* Choose a standard blit function */
231  if (map->identity && !(map->info.flags & ~SDL_COPY_RLE_DESIRED)) {
232  blit = SDL_BlitCopy;
233  } else if (surface->format->Rloss > 8 || dst->format->Rloss > 8) {
234  /* Greater than 8 bits per channel not supported yet */
236  return SDL_SetError("Blit combination not supported");
237  }
238 #if SDL_HAVE_BLIT_0
239  else if (surface->format->BitsPerPixel < 8 &&
240  SDL_ISPIXELFORMAT_INDEXED(surface->format->format)) {
241  blit = SDL_CalculateBlit0(surface);
242  }
243 #endif
244 #if SDL_HAVE_BLIT_1
245  else if (surface->format->BytesPerPixel == 1 &&
246  SDL_ISPIXELFORMAT_INDEXED(surface->format->format)) {
247  blit = SDL_CalculateBlit1(surface);
248  }
249 #endif
250 #if SDL_HAVE_BLIT_A
251  else if (map->info.flags & SDL_COPY_BLEND) {
252  blit = SDL_CalculateBlitA(surface);
253  }
254 #endif
255 #if SDL_HAVE_BLIT_N
256  else {
257  blit = SDL_CalculateBlitN(surface);
258  }
259 #endif
260 #if SDL_HAVE_BLIT_AUTO
261  if (blit == NULL) {
262  Uint32 src_format = surface->format->format;
263  Uint32 dst_format = dst->format->format;
264 
265  blit =
266  SDL_ChooseBlitFunc(src_format, dst_format, map->info.flags,
268  }
269 #endif
270 
271 #ifndef TEST_SLOW_BLIT
272  if (blit == NULL)
273 #endif
274  {
275  Uint32 src_format = surface->format->format;
276  Uint32 dst_format = dst->format->format;
277 
278  if (!SDL_ISPIXELFORMAT_INDEXED(src_format) &&
279  !SDL_ISPIXELFORMAT_FOURCC(src_format) &&
280  !SDL_ISPIXELFORMAT_INDEXED(dst_format) &&
281  !SDL_ISPIXELFORMAT_FOURCC(dst_format)) {
282  blit = SDL_Blit_Slow;
283  }
284  }
285  map->data = blit;
286 
287  /* Make sure we have a blit function */
288  if (blit == NULL) {
290  return SDL_SetError("Blit combination not supported");
291  }
292 
293  return 0;
294 }
295 
296 /* vi: set ts=4 sw=4 expandtab: */
SDL_BlitInfo::src
Uint8 * src
Definition: SDL_blit.h:58
SDL_UnlockSurface
#define SDL_UnlockSurface
Definition: SDL_dynapi_overrides.h:449
SDL_BlitInfo::src_skip
int src_skip
Definition: SDL_blit.h:61
Uint8
uint8_t Uint8
Definition: SDL_stdinc.h:179
SDL_ChooseBlitFunc
static SDL_BlitFunc SDL_ChooseBlitFunc(Uint32 src_format, Uint32 dst_format, int flags, SDL_BlitFuncEntry *entries)
Definition: SDL_blit.c:130
SDL_CPU_SSE2
#define SDL_CPU_SSE2
Definition: SDL_blit.h:52
SDL_CPU_SSE
#define SDL_CPU_SSE
Definition: SDL_blit.h:51
SDL_PixelFormat::BytesPerPixel
Uint8 BytesPerPixel
Definition: SDL_pixels.h:323
SDL_BlitInfo::src_pitch
int src_pitch
Definition: SDL_blit.h:60
SDL_HasAltiVec
#define SDL_HasAltiVec
Definition: SDL_dynapi_overrides.h:104
SDL_CPU_ALTIVEC_NOPREFETCH
#define SDL_CPU_ALTIVEC_NOPREFETCH
Definition: SDL_blit.h:54
Uint16
uint16_t Uint16
Definition: SDL_stdinc.h:191
SDL_CPU_ANY
#define SDL_CPU_ANY
Definition: SDL_blit.h:48
SDL_Surface
A collection of pixels used in software blitting.
Definition: SDL_surface.h:71
SDL_CalculateBlit
int SDL_CalculateBlit(SDL_Surface *surface)
Definition: SDL_blit.c:196
SDL_BlitMap
Definition: SDL_blit.h:88
SDL_Has3DNow
#define SDL_Has3DNow
Definition: SDL_dynapi_overrides.h:106
SDL_RLEACCEL
#define SDL_RLEACCEL
Definition: SDL_surface.h:54
NULL
#define NULL
Definition: begin_code.h:167
surface
EGLSurface surface
Definition: eglext.h:248
SDL_BlitInfo::dst_w
int dst_w
Definition: SDL_blit.h:63
SDL_BlitInfo
Definition: SDL_blit.h:57
SDL_UnRLESurface
void SDL_UnRLESurface(SDL_Surface *surface, int recode)
Definition: SDL_RLEaccel.c:1547
SDL_UseAltivecPrefetch
static SDL_bool SDL_UseAltivecPrefetch()
Definition: SDL_blit.c:122
SDL_blit_copy.h
SDLCALL
#define SDLCALL
Definition: SDL_internal.h:49
SDL_BlitInfo::dst_h
int dst_h
Definition: SDL_blit.h:63
SDL_MUSTLOCK
#define SDL_MUSTLOCK(S)
Definition: SDL_surface.h:62
SDL_COPY_COLORKEY
#define SDL_COPY_COLORKEY
Definition: SDL_blit.h:40
SDL_RectEmpty
SDL_FORCE_INLINE SDL_bool SDL_RectEmpty(const SDL_Rect *r)
Returns true if the rectangle has no area.
Definition: SDL_rect.h:108
Uint32
uint32_t Uint32
Definition: SDL_stdinc.h:203
SDL_Blit_Slow
void SDL_Blit_Slow(SDL_BlitInfo *info)
Definition: SDL_blit_slow.c:31
SDL_ISPIXELFORMAT_INDEXED
#define SDL_ISPIXELFORMAT_INDEXED(format)
Definition: SDL_pixels.h:134
map
const GLubyte GLuint GLuint GLuint GLuint alpha GLboolean GLboolean GLboolean GLboolean alpha GLint GLint GLsizei GLsizei GLenum type GLenum GLint GLenum GLint GLint GLsizei GLsizei GLint border GLenum GLint GLint GLint GLint GLint GLsizei GLsizei height GLsizei GLsizei GLenum GLenum const GLvoid *pixels GLenum GLint GLint GLint GLint j2 GLdouble GLdouble GLdouble GLdouble GLdouble GLdouble zFar GLenum GLenum GLint *params GLenum GLenum GLint *params GLenum GLenum GLint *params GLenum GLenum GLfloat *params GLenum GLint GLenum GLenum GLvoid *pixels GLenum GLint GLenum GLint *params GLenum GLenum GLint *params GLenum GLsizei const GLvoid *pointer GLenum GLenum const GLint *params GLenum GLfloat GLfloat GLint GLint const GLfloat *points GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat *points GLint GLfloat GLfloat GLint GLfloat GLfloat v2 GLenum GLenum const GLint *params GLdouble GLdouble GLdouble GLdouble GLdouble GLdouble zFar GLenum map
Definition: SDL_glfuncs.h:291
SDL_Rect::x
int x
Definition: SDL_rect.h:79
result
GLuint64EXT * result
Definition: SDL_opengl_glext.h:9435
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int w
Definition: SDL_rect.h:80
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#define SDL_CPU_3DNOW
Definition: SDL_blit.h:50
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#define SDL_COPY_RLE_DESIRED
Definition: SDL_blit.h:42
dst
GLenum GLenum dst
Definition: SDL_opengl_glext.h:1740
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int src_w
Definition: SDL_blit.h:59
SDL_BlitInfo::dst
Uint8 * dst
Definition: SDL_blit.h:62
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#define SDL_COPY_MUL
Definition: SDL_blit.h:39
SDL_blit_auto.h
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Definition: SDL_blit.h:66
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int y
Definition: SDL_rect.h:79
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#define SDL_CPU_MMX
Definition: SDL_blit.h:49
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int h
Definition: SDL_rect.h:80
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#define SDL_CPU_ALTIVEC_PREFETCH
Definition: SDL_blit.h:53
SDL_blit.h
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#define SDL_COPY_BLEND
Definition: SDL_blit.h:36
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int SDL_RLESurface(SDL_Surface *surface)
Definition: SDL_RLEaccel.c:1407
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int dst_skip
Definition: SDL_blit.h:65
SDL_CalculateBlitA
SDL_BlitFunc SDL_CalculateBlitA(SDL_Surface *surface)
Definition: SDL_blit_A.c:1335
key
GLuint64 key
Definition: gl2ext.h:2192
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int src_h
Definition: SDL_blit.h:59
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SDL_BlitFuncEntry SDL_GeneratedBlitFuncTable[]
Definition: SDL_blit_auto.c:7547
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Definition: SDL_blit.h:83
SDL_TRUE
@ SDL_TRUE
Definition: SDL_stdinc.h:164
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#define SDL_sscanf
Definition: SDL_dynapi_overrides.h:39
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#define SDL_COPY_MODULATE_ALPHA
Definition: SDL_blit.h:35
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Definition: SDL_blit.h:67
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#define SDL_LockSurface
Definition: SDL_dynapi_overrides.h:448
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#define SDL_HasMMX
Definition: SDL_dynapi_overrides.h:105
src
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Definition: SDL_opengl_glext.h:1740
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#define SDL_getenv
Definition: SDL_dynapi_overrides.h:378
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#define SDL_ISPIXELFORMAT_FOURCC(format)
Definition: SDL_pixels.h:167
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SDL_BlitFunc SDL_CalculateBlitN(SDL_Surface *surface)
Definition: SDL_blit_N.c:3360
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#define SDL_SetError
Definition: SDL_dynapi_overrides.h:30
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void SDL_InvalidateMap(SDL_BlitMap *map)
Definition: SDL_pixels.c:979
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#define SDL_COPY_NEAREST
Definition: SDL_blit.h:41
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A rectangle, with the origin at the upper left (integer).
Definition: SDL_rect.h:78
SDL_CalculateBlit0
SDL_BlitFunc SDL_CalculateBlit0(SDL_Surface *surface)
Definition: SDL_blit_0.c:456
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Definition: SDL_blit.h:78
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int dst_pitch
Definition: SDL_blit.h:64
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#define SDL_COPY_ADD
Definition: SDL_blit.h:37
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#define SDL_HasSSE2
Definition: SDL_dynapi_overrides.h:108
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#define SDL_COPY_MOD
Definition: SDL_blit.h:38
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SDL_BlitFunc SDL_CalculateBlit1(SDL_Surface *surface)
Definition: SDL_blit_1.c:524
SDL_bool
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Definition: SDL_stdinc.h:162
SDL_pixels_c.h
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#define SDL_HasSSE
Definition: SDL_dynapi_overrides.h:107
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#define SDL_COPY_MODULATE_COLOR
Definition: SDL_blit.h:34
SDL_FALSE
@ SDL_FALSE
Definition: SDL_stdinc.h:163
SDL_sysvideo.h
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static int SDL_SoftBlit(SDL_Surface *src, SDL_Rect *srcrect, SDL_Surface *dst, SDL_Rect *dstrect)
Definition: SDL_blit.c:34
flags
GLbitfield flags
Definition: SDL_opengl_glext.h:1483
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
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void(* SDL_BlitFunc)(SDL_BlitInfo *info)
Definition: SDL_blit.h:74
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void SDL_BlitCopy(SDL_BlitInfo *info)
Definition: SDL_blit_copy.c:91