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author Miodrag Milanovic <mmicko@gmail.com>2016-11-16 16:26:13 +0100
committer Miodrag Milanovic <mmicko@gmail.com>2016-11-16 16:28:01 +0100
commit47a05778bff9388fc6c479461dd3804c79d7b539 (patch)
treebb3d4dc8df676b8aa478339b3fd0cd305dc4ac4d /3rdparty/SDL2/src/render/software/SDL_rotate.c
parente61b392edfbfe5b9d70908c087632da915a3abd8 (diff)
Updated SDL2 to 2.0.5 (nw)
Diffstat (limited to '3rdparty/SDL2/src/render/software/SDL_rotate.c')
-rw-r--r--3rdparty/SDL2/src/render/software/SDL_rotate.c165
1 files changed, 124 insertions, 41 deletions
diff --git a/3rdparty/SDL2/src/render/software/SDL_rotate.c b/3rdparty/SDL2/src/render/software/SDL_rotate.c
index 8d92758f875..0141d174d9f 100644
--- a/3rdparty/SDL2/src/render/software/SDL_rotate.c
+++ b/3rdparty/SDL2/src/render/software/SDL_rotate.c
@@ -110,31 +110,105 @@ SDLgfx_rotozoomSurfaceSizeTrig(int width, int height, double angle,
int *dstwidth, int *dstheight,
double *cangle, double *sangle)
{
- double x, y, cx, cy, sx, sy;
- double radangle;
- int dstwidthhalf, dstheighthalf;
+ /* The trig code below gets the wrong size (due to FP inaccuracy?) when angle is a multiple of 90 degrees */
+ int angle90 = (int)(angle/90);
+ if(angle90 == angle/90) { /* if the angle is a multiple of 90 degrees */
+ angle90 %= 4;
+ if(angle90 < 0) angle90 += 4; /* 0:0 deg, 1:90 deg, 2:180 deg, 3:270 deg */
+ if(angle90 & 1) {
+ *dstwidth = height;
+ *dstheight = width;
+ *cangle = 0;
+ *sangle = angle90 == 1 ? -1 : 1; /* reversed because our rotations are clockwise */
+ } else {
+ *dstwidth = width;
+ *dstheight = height;
+ *cangle = angle90 == 0 ? 1 : -1;
+ *sangle = 0;
+ }
+ } else {
+ 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); /* reverse the angle because our rotations are clockwise */
+ *sangle = SDL_sin(radangle);
+ *cangle = SDL_cos(radangle);
+ x = (double)(width / 2);
+ y = (double)(height / 2);
+ cx = *cangle * x;
+ cy = *cangle * y;
+ sx = *sangle * x;
+ sy = *sangle * y;
+
+ dstwidthhalf = MAX((int)
+ SDL_ceil(MAX(MAX(MAX(SDL_fabs(cx + sy), SDL_fabs(cx - sy)), SDL_fabs(-cx + sy)), SDL_fabs(-cx - sy))), 1);
+ dstheighthalf = MAX((int)
+ SDL_ceil(MAX(MAX(MAX(SDL_fabs(sx + cy), SDL_fabs(sx - cy)), SDL_fabs(-sx + cy)), SDL_fabs(-sx - cy))), 1);
+ *dstwidth = 2 * dstwidthhalf;
+ *dstheight = 2 * dstheighthalf;
+ }
+}
- /*
- * Determine destination width and height by rotating a centered source box
- */
- radangle = angle * (M_PI / 180.0);
- *sangle = SDL_sin(radangle);
- *cangle = SDL_cos(radangle);
- x = (double)(width / 2);
- y = (double)(height / 2);
- cx = *cangle * x;
- cy = *cangle * y;
- sx = *sangle * x;
- sy = *sangle * y;
-
- dstwidthhalf = MAX((int)
- SDL_ceil(MAX(MAX(MAX(SDL_fabs(cx + sy), SDL_fabs(cx - sy)), SDL_fabs(-cx + sy)), SDL_fabs(-cx - sy))), 1);
- dstheighthalf = MAX((int)
- SDL_ceil(MAX(MAX(MAX(SDL_fabs(sx + cy), SDL_fabs(sx - cy)), SDL_fabs(-sx + cy)), SDL_fabs(-sx - cy))), 1);
- *dstwidth = 2 * dstwidthhalf;
- *dstheight = 2 * dstheighthalf;
+/* Computes source pointer X/Y increments for a rotation that's a multiple of 90 degrees. */
+static void
+computeSourceIncrements90(SDL_Surface * src, int bpp, int angle, int flipx, int flipy,
+ int *sincx, int *sincy, int *signx, int *signy)
+{
+ int pitch = flipy ? -src->pitch : src->pitch;
+ if (flipx) {
+ bpp = -bpp;
+ }
+ switch (angle) { /* 0:0 deg, 1:90 deg, 2:180 deg, 3:270 deg */
+ case 0: *sincx = bpp; *sincy = pitch - src->w * *sincx; *signx = *signy = 1; break;
+ case 1: *sincx = -pitch; *sincy = bpp - *sincx * src->h; *signx = 1; *signy = -1; break;
+ case 2: *sincx = -bpp; *sincy = -src->w * *sincx - pitch; *signx = *signy = -1; break;
+ case 3: default: *sincx = pitch; *sincy = -*sincx * src->h - bpp; *signx = -1; *signy = 1; break;
+ }
+ if (flipx) {
+ *signx = -*signx;
+ }
+ if (flipy) {
+ *signy = -*signy;
+ }
+}
+
+/* Performs a relatively fast rotation/flip when the angle is a multiple of 90 degrees. */
+#define TRANSFORM_SURFACE_90(pixelType) \
+ int dy, dincy = dst->pitch - dst->w*sizeof(pixelType), sincx, sincy, signx, signy; \
+ Uint8 *sp = (Uint8*)src->pixels, *dp = (Uint8*)dst->pixels, *de; \
+ \
+ computeSourceIncrements90(src, sizeof(pixelType), angle, flipx, flipy, &sincx, &sincy, &signx, &signy); \
+ if (signx < 0) sp += (src->w-1)*sizeof(pixelType); \
+ if (signy < 0) sp += (src->h-1)*src->pitch; \
+ \
+ for (dy = 0; dy < dst->h; sp += sincy, dp += dincy, dy++) { \
+ if (sincx == sizeof(pixelType)) { /* if advancing src and dest equally, use memcpy */ \
+ SDL_memcpy(dp, sp, dst->w*sizeof(pixelType)); \
+ sp += dst->w*sizeof(pixelType); \
+ dp += dst->w*sizeof(pixelType); \
+ } else { \
+ for (de = dp + dst->w*sizeof(pixelType); dp != de; sp += sincx, dp += sizeof(pixelType)) { \
+ *(pixelType*)dp = *(pixelType*)sp; \
+ } \
+ } \
+ }
+
+static void
+transformSurfaceRGBA90(SDL_Surface * src, SDL_Surface * dst, int angle, int flipx, int flipy)
+{
+ TRANSFORM_SURFACE_90(tColorRGBA);
+}
+
+static void
+transformSurfaceY90(SDL_Surface * src, SDL_Surface * dst, int angle, int flipx, int flipy)
+{
+ TRANSFORM_SURFACE_90(tColorY);
}
+#undef TRANSFORM_SURFACE_90
/* !
\brief Internal 32 bit rotozoomer with optional anti-aliasing.
@@ -341,9 +415,9 @@ SDLgfx_rotateSurface(SDL_Surface * src, double angle, int centerx, int centery,
{
SDL_Surface *rz_src;
SDL_Surface *rz_dst;
- int is32bit;
+ int is32bit, angle90;
int i;
- Uint8 r,g,b;
+ Uint8 r = 0, g = 0, b = 0;
Uint32 colorkey = 0;
int colorKeyAvailable = 0;
double sangleinv, cangleinv;
@@ -370,18 +444,13 @@ SDLgfx_rotateSurface(SDL_Surface * src, double angle, int centerx, int centery,
*/
rz_src = src;
} else {
- Uint32 format = SDL_MasksToPixelFormatEnum(32,
-#if SDL_BYTEORDER == SDL_LIL_ENDIAN
- 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000
-#else
- 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff
-#endif
- );
- rz_src = SDL_ConvertSurfaceFormat(src, format, src->flags);
+ rz_src = SDL_ConvertSurfaceFormat(src, SDL_PIXELFORMAT_ARGB32, src->flags);
+ if (rz_src == NULL) {
+ return NULL;
+ }
is32bit = 1;
}
-
/* Determine target size */
/* _rotozoomSurfaceSizeTrig(rz_src->w, rz_src->h, angle, &dstwidth, &dstheight, &cangle, &sangle); */
@@ -394,7 +463,6 @@ SDLgfx_rotateSurface(SDL_Surface * src, double angle, int centerx, int centery,
/*
* Alloc space to completely contain the rotated surface
*/
- rz_dst = NULL;
if (is32bit) {
/*
* Target surface is 32bit with source RGBA/ABGR ordering
@@ -430,6 +498,18 @@ SDLgfx_rotateSurface(SDL_Surface * src, double angle, int centerx, int centery,
SDL_LockSurface(rz_src);
}
+ /* check if the rotation is a multiple of 90 degrees so we can take a fast path and also somewhat reduce
+ * the off-by-one problem in _transformSurfaceRGBA that expresses itself when the rotation is near
+ * multiples of 90 degrees.
+ */
+ angle90 = (int)(angle/90);
+ if (angle90 == angle/90) {
+ angle90 %= 4;
+ if (angle90 < 0) angle90 += 4; /* 0:0 deg, 1:90 deg, 2:180 deg, 3:270 deg */
+ } else {
+ angle90 = -1;
+ }
+
/*
* Check which kind of surface we have
*/
@@ -437,10 +517,11 @@ SDLgfx_rotateSurface(SDL_Surface * src, double angle, int centerx, int centery,
/*
* Call the 32bit transformation routine to do the rotation (using alpha)
*/
- _transformSurfaceRGBA(rz_src, rz_dst, centerx, centery,
- (int) (sangleinv), (int) (cangleinv),
- flipx, flipy,
- smooth);
+ if (angle90 >= 0) {
+ transformSurfaceRGBA90(rz_src, rz_dst, angle90, flipx, flipy);
+ } else {
+ _transformSurfaceRGBA(rz_src, rz_dst, centerx, centery, (int) (sangleinv), (int) (cangleinv), flipx, flipy, smooth);
+ }
/*
* Turn on source-alpha support
*/
@@ -457,9 +538,11 @@ SDLgfx_rotateSurface(SDL_Surface * src, double angle, int centerx, int centery,
/*
* Call the 8bit transformation routine to do the rotation
*/
- transformSurfaceY(rz_src, rz_dst, centerx, centery,
- (int) (sangleinv), (int) (cangleinv),
- flipx, flipy);
+ if(angle90 >= 0) {
+ transformSurfaceY90(rz_src, rz_dst, angle90, flipx, flipy);
+ } else {
+ transformSurfaceY(rz_src, rz_dst, centerx, centery, (int)(sangleinv), (int)(cangleinv), flipx, flipy);
+ }
SDL_SetColorKey(rz_dst, /* SDL_SRCCOLORKEY */ SDL_TRUE | SDL_RLEACCEL, _colorkey(rz_src));
}