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cleanup

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This commit is contained in:
Glenn Maynard
2004-03-19 23:14:30 +00:00
parent 0b61b60baa
commit b6e2805cd5
2 changed files with 58 additions and 81 deletions
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stepmania/src/SDL_rotozoom.cpp
+24 -45
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@@ -11,17 +11,6 @@
#include <vector>
using namespace std;
struct tColorRGBA {
Uint8 c[4];
};
/*
32bit Zoomer with optional anti-aliasing by bilinear interpolation.
Zooms 32bit RGBA/ABGR 'src' surface to 'dst' surface.
*/
/* Coordinate 0x0 represents the exact top-left corner of a bitmap. .5x.5
* represents the center of the top-left pixel; 1x1 is the center of the top
* square of pixels.
@@ -33,8 +22,8 @@ struct tColorRGBA {
static void ZoomSurface( SDL_Surface * src, SDL_Surface * dst )
{
/* Ratio from source to dest. */
float sx = float(src->w) / dst->w;
float sy = float(src->h) / dst->h;
const float sx = float(src->w) / dst->w;
const float sy = float(src->h) / dst->h;
/* For each destination coordinate, two source rows, two source columns
* and the percentage of the first row and first column: */
@@ -99,60 +88,45 @@ static void ZoomSurface( SDL_Surface * src, SDL_Surface * dst )
}
}
const tColorRGBA *sp = (tColorRGBA *) src->pixels;
const Uint8 *sp = (Uint8 *) src->pixels;
/* Scan destination */
for( y = 0; y < dst->h; y++ )
{
tColorRGBA *dp = (tColorRGBA *) ((Uint8 *) dst->pixels + dst->pitch*y);
Uint8 *dp = ((Uint8 *) dst->pixels + dst->pitch*y);
/* current source pointer and next source pointer (first and second
* rows sampled for this row): */
const tColorRGBA *csp = (tColorRGBA *) ((Uint8 *) sp + esy0[y] * src->pitch);
const tColorRGBA *ncsp = (tColorRGBA *) ((Uint8 *) sp + esy1[y] * src->pitch);
const Uint8 *csp = (Uint8 *) (sp + esy0[y] * src->pitch);
const Uint8 *ncsp = (Uint8 *) (sp + esy1[y] * src->pitch);
for( x = 0; x < dst->w; x++ )
{
/* Grab pointers to the sampled pixels: */
const tColorRGBA *c00 = csp + esx0[x];
const tColorRGBA *c01 = csp + esx1[x];
const tColorRGBA *c10 = ncsp + esx0[x];
const tColorRGBA *c11 = ncsp + esx1[x];
const Uint8 *c00 = (Uint8 *) (csp + esx0[x]*4);
const Uint8 *c01 = (Uint8 *) (csp + esx1[x]*4);
const Uint8 *c10 = (Uint8 *) (ncsp + esx0[x]*4);
const Uint8 *c11 = (Uint8 *) (ncsp + esx1[x]*4);
Uint8 color[4];
for( int c = 0; c < 4; ++c )
{
float x0, x1;
x0 = c00->c[c] * ex0[x];
x0 += c01->c[c] * (1-ex0[x]);
x1 = c10->c[c] * ex0[x];
x1 += c11->c[c] * (1-ex0[x]);
x0 = c00[c] * ex0[x];
x0 += c01[c] * (1-ex0[x]);
x1 = c10[c] * ex0[x];
x1 += c11[c] * (1-ex0[x]);
const float res = (x0 * ey0[y]) + (x1 * (1-ey0[y]));
dp->c[c] = Uint8(res);
color[c] = Uint8(res);
}
*(Uint32 *) dp = *(Uint32 *) color;
/* Advance destination pointer. */
dp++;
dp += 4;
}
}
}
static SDL_Surface *zoomSurface_ll( SDL_Surface *src, int dstwidth, int dstheight )
{
if( src == NULL )
return NULL;
SDL_Surface *dst =
SDL_CreateRGBSurface(SDL_SWSURFACE, dstwidth, dstheight, 32,
src->format->Rmask, src->format->Gmask,
src->format->Bmask, src->format->Amask);
ZoomSurface( src, dst );
return dst;
}
void zoomSurface( SDL_Surface *&src, int dstwidth, int dstheight )
{
if( src == NULL )
@@ -172,7 +146,12 @@ void zoomSurface( SDL_Surface *&src, int dstwidth, int dstheight )
int target_width = int(src->w*xscale + .5);
int target_height = int(src->h*yscale + .5);
SDL_Surface *dst = zoomSurface_ll(src, target_width, target_height);
SDL_Surface *dst =
SDL_CreateRGBSurface(SDL_SWSURFACE, target_width, target_height, 32,
src->format->Rmask, src->format->Gmask,
src->format->Bmask, src->format->Amask);
ZoomSurface( src, dst );
SDL_FreeSurface(src);