#include <math.h>
#include "fc_prehdrs.h"
#include <SDL3/SDL.h>

Macros
#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.

Macro Definition Documentation

◆ M_PI

#define M_PI 3.1415926535897932384626433832795

Definition at line 41 of file SDL3_rotozoom.h.

◆ SDL2_ROTOZOOM_SCOPE

#define SDL2_ROTOZOOM_SCOPE extern

Definition at line 73 of file SDL3_rotozoom.h.

◆ SMOOTHING_OFF

#define SMOOTHING_OFF 0

Disable anti-aliasing (no smoothing).

Definition at line 54 of file SDL3_rotozoom.h.

◆ SMOOTHING_ON

#define SMOOTHING_ON 1

Enable anti-aliasing (smoothing).

Definition at line 59 of file SDL3_rotozoom.h.

Function Documentation

◆ rotateSurface90Degrees()

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

src	Source surface to rotate.
numClockwiseTurns	Number 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 539 of file SDL3_rotozoom.c.

◆ rotozoomSurface()

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

src	The surface to rotozoom.
angle	The angle to rotate in degrees.
zoom	The scaling factor.
smooth	Antialiasing flag; set to SMOOTHING_ON to enable.

Returns: The new rotozoomed surface.

Definition at line 769 of file SDL3_rotozoom.c.

◆ rotozoomSurfaceSize()

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

width	The source surface width.
height	The source surface height.
angle	The angle to rotate in degrees.
zoom	The scaling factor.
dstwidth	The calculated width of the rotozoomed destination surface.
dstheight	The calculated height of the rotozoomed destination surface.

Definition at line 747 of file SDL3_rotozoom.c.

◆ rotozoomSurfaceSizeXY()

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

width	The source surface width.
height	The source surface height.
angle	The angle to rotate in degrees.
zoomx	The horizontal scaling factor.
zoomy	The vertical scaling factor.
dstwidth	The calculated width of the rotozoomed destination surface.
dstheight	The calculated height of the rotozoomed destination surface.

Definition at line 730 of file SDL3_rotozoom.c.

◆ rotozoomSurfaceXY()

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

src	The surface to rotozoom.
angle	The angle to rotate in degrees.
zoomx	The horizontal scaling factor.
zoomy	The vertical scaling factor.
smooth	Antialiasing flag; set to SMOOTHING_ON to enable.

Returns: The new rotozoomed surface.

Definition at line 790 of file SDL3_rotozoom.c.

Referenced by rotozoomSurface().

◆ shrinkSurface()

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

src	The surface to shrink.
factorx	The horizontal shrinking ratio.
factory	The vertical shrinking ratio.

Returns: The new, shrunken surface.

Definition at line 1175 of file SDL3_rotozoom.c.

◆ zoomSurface()

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

src	The surface to zoom.
zoomx	The horizontal zoom factor.
zoomy	The vertical zoom factor.
smooth	Antialiasing flag; set to SMOOTHING_ON to enable.

Returns: The new, zoomed surface.

Definition at line 1047 of file SDL3_rotozoom.c.

Referenced by change_nation_label(), create_select_tech_icon(), economy_report_dialog_popup(), get_scaled_city_map(), popup_players_dialog(), popup_races_dialog(), popup_worklist_editor(), real_science_report_dialog_update(), redraw_city_dialog(), redraw_happiness_city_dialog(), redraw_unit_info_label(), resize_surface(), resize_surface_box(), and update_intel_dialog().

◆ zoomSurfaceSize()

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

width	The width of the source surface to zoom.
height	The height of the source surface to zoom.
zoomx	The horizontal zoom factor.
zoomy	The vertical zoom factor.
dstwidth	Pointer to an integer to store the calculated width of the zoomed target surface.
dstheight	Pointer to an integer to store the calculated height of the zoomed target surface.

Definition at line 997 of file SDL3_rotozoom.c.

Referenced by rotozoomSurfaceXY(), and zoomSurface().

Macros

Functions

Macro Definition Documentation

◆ M_PI

◆ SDL2_ROTOZOOM_SCOPE

◆ SMOOTHING_OFF

◆ SMOOTHING_ON

Function Documentation

◆ rotateSurface90Degrees()

◆ rotozoomSurface()

◆ rotozoomSurfaceSize()

◆ rotozoomSurfaceSizeXY()

◆ rotozoomSurfaceXY()

◆ shrinkSurface()

◆ zoomSurface()

◆ zoomSurfaceSize()