SDL2_gfx  1.0.1
GraphicsprimitivesandsurfacefunctionsforSDL2
Defines | Functions
I:/Sources/sdl2gfx/SDL2_rotozoom.h File Reference
#include <math.h>
#include "SDL.h"

Go to the source code of this file.

Defines

#define M_PI   3.1415926535897932384626433832795
#define SMOOTHING_OFF   0
 Disable anti-aliasing (no smoothing).
#define SMOOTHING_ON   1
 Enable anti-aliasing (smoothing).
#define SDL2_ROTOZOOM_SCOPE   extern

Functions

SDL2_ROTOZOOM_SCOPE SDL_Surface * rotozoomSurface (SDL_Surface *src, double angle, double zoom, int smooth)
 Rotates and zooms a surface and optional anti-aliasing.
SDL2_ROTOZOOM_SCOPE SDL_Surface * rotozoomSurfaceXY (SDL_Surface *src, double angle, double zoomx, double zoomy, int smooth)
 Rotates and zooms a surface with different horizontal and vertival scaling factors and optional anti-aliasing.
SDL2_ROTOZOOM_SCOPE void rotozoomSurfaceSize (int width, int height, double angle, double zoom, int *dstwidth, int *dstheight)
 Returns the size of the resulting target surface for a rotozoomSurface() call.
SDL2_ROTOZOOM_SCOPE void rotozoomSurfaceSizeXY (int width, int height, double angle, double zoomx, double zoomy, int *dstwidth, int *dstheight)
 Returns the size of the resulting target surface for a rotozoomSurfaceXY() call.
SDL2_ROTOZOOM_SCOPE SDL_Surface * zoomSurface (SDL_Surface *src, double zoomx, double zoomy, int smooth)
 Zoom a surface by independent horizontal and vertical factors with optional smoothing.
SDL2_ROTOZOOM_SCOPE void zoomSurfaceSize (int width, int height, double zoomx, double zoomy, int *dstwidth, int *dstheight)
 Calculates the size of the target surface for a zoomSurface() call.
SDL2_ROTOZOOM_SCOPE SDL_Surface * shrinkSurface (SDL_Surface *src, int factorx, int factory)
 Shrink a surface by an integer ratio using averaging.
SDL2_ROTOZOOM_SCOPE SDL_Surface * rotateSurface90Degrees (SDL_Surface *src, int numClockwiseTurns)
 Rotates a 8/16/24/32 bit surface in increments of 90 degrees.

Define Documentation

#define M_PI   3.1415926535897932384626433832795

Definition at line 41 of file SDL2_rotozoom.h.

#define SDL2_ROTOZOOM_SCOPE   extern

Definition at line 70 of file SDL2_rotozoom.h.

#define SMOOTHING_OFF   0

Disable anti-aliasing (no smoothing).

Definition at line 51 of file SDL2_rotozoom.h.

#define SMOOTHING_ON   1

Enable anti-aliasing (smoothing).

Definition at line 56 of file SDL2_rotozoom.h.


Function Documentation

SDL2_ROTOZOOM_SCOPE SDL_Surface* rotateSurface90Degrees ( SDL_Surface *  src,
int  numClockwiseTurns 
)

Rotates a 8/16/24/32 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 no scanning or interpolation takes place. Input surface must be 8/16/24/32 bit. (code contributed by J. Schiller, improved by C. Allport and A. Schiffler)

Parameters:
srcSource surface to rotate.
numClockwiseTurnsNumber of clockwise 90 degree turns to apply to the source.
Returns:
The new, rotated surface; or NULL for surfaces with incorrect input format.

Definition at line 803 of file SDL2_rotozoom.c.

SDL2_ROTOZOOM_SCOPE SDL_Surface* rotozoomSurface ( SDL_Surface *  src,
double  angle,
double  zoom,
int  smooth 
)

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.

Parameters:
srcThe surface to rotozoom.
angleThe angle to rotate in degrees.
zoomThe scaling factor.
smoothAntialiasing flag; set to SMOOTHING_ON to enable.
Returns:
The new rotozoomed surface.

Definition at line 1035 of file SDL2_rotozoom.c.

SDL2_ROTOZOOM_SCOPE void rotozoomSurfaceSize ( int  width,
int  height,
double  angle,
double  zoom,
int *  dstwidth,
int *  dstheight 
)

Returns the size of the resulting target surface for a rotozoomSurface() call.

Parameters:
widthThe source surface width.
heightThe source surface height.
angleThe angle to rotate in degrees.
zoomThe scaling factor.
dstwidthThe calculated width of the rotozoomed destination surface.
dstheightThe calculated height of the rotozoomed destination surface.

Definition at line 1013 of file SDL2_rotozoom.c.

SDL2_ROTOZOOM_SCOPE void rotozoomSurfaceSizeXY ( int  width,
int  height,
double  angle,
double  zoomx,
double  zoomy,
int *  dstwidth,
int *  dstheight 
)

Returns the size of the resulting target surface for a rotozoomSurfaceXY() call.

Parameters:
widthThe source surface width.
heightThe source surface height.
angleThe angle to rotate in degrees.
zoomxThe horizontal scaling factor.
zoomyThe vertical scaling factor.
dstwidthThe calculated width of the rotozoomed destination surface.
dstheightThe calculated height of the rotozoomed destination surface.

Definition at line 996 of file SDL2_rotozoom.c.

SDL2_ROTOZOOM_SCOPE SDL_Surface* rotozoomSurfaceXY ( SDL_Surface *  src,
double  angle,
double  zoomx,
double  zoomy,
int  smooth 
)

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.

Parameters:
srcThe surface to rotozoom.
angleThe angle to rotate in degrees.
zoomxThe horizontal scaling factor.
zoomyThe vertical scaling factor.
smoothAntialiasing flag; set to SMOOTHING_ON to enable.
Returns:
The new rotozoomed surface.

Definition at line 1056 of file SDL2_rotozoom.c.

SDL2_ROTOZOOM_SCOPE SDL_Surface* shrinkSurface ( SDL_Surface *  src,
int  factorx,
int  factory 
)

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.

Parameters:
srcThe surface to shrink.
factorxThe horizontal shrinking ratio.
factoryThe vertical shrinking ratio.
Returns:
The new, shrunken surface.

Definition at line 1512 of file SDL2_rotozoom.c.

SDL2_ROTOZOOM_SCOPE SDL_Surface* zoomSurface ( SDL_Surface *  src,
double  zoomx,
double  zoomy,
int  smooth 
)

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.

Parameters:
srcThe surface to zoom.
zoomxThe horizontal zoom factor.
zoomyThe vertical zoom factor.
smoothAntialiasing flag; set to SMOOTHING_ON to enable.
Returns:
The new, zoomed surface.

Definition at line 1361 of file SDL2_rotozoom.c.

SDL2_ROTOZOOM_SCOPE void zoomSurfaceSize ( int  width,
int  height,
double  zoomx,
double  zoomy,
int *  dstwidth,
int *  dstheight 
)

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.

Parameters:
widthThe width of the source surface to zoom.
heightThe height of the source surface to zoom.
zoomxThe horizontal zoom factor.
zoomyThe vertical zoom factor.
dstwidthPointer to an integer to store the calculated width of the zoomed target surface.
dstheightPointer to an integer to store the calculated height of the zoomed target surface.

Definition at line 1311 of file SDL2_rotozoom.c.