1

/* $Id$ */

     2

     3

/** @file zoom.hpp */

     4

     5

#ifndef ZOOM_HPP

     6

#define ZOOM_HPP

     7

     8

#include "helpers.hpp"

     9

    10

enum ZoomLevel {

    11

	/* Our possible zoom-levels */

    12

	ZOOM_LVL_BEGIN  = 0,

    13

	ZOOM_LVL_NORMAL = 0,

    14

	ZOOM_LVL_OUT_2X,

    15

	ZOOM_LVL_OUT_4X,

    16

	ZOOM_LVL_OUT_8X,

    17

	ZOOM_LVL_END,

    18

    19

	/* Here we define in which zoom viewports are */

    20

	ZOOM_LVL_VIEWPORT = ZOOM_LVL_NORMAL,

    21

	ZOOM_LVL_NEWS     = ZOOM_LVL_NORMAL,

    22

	ZOOM_LVL_INDUSTRY = ZOOM_LVL_OUT_2X,

    23

	ZOOM_LVL_TOWN     = ZOOM_LVL_OUT_2X,

    24

	ZOOM_LVL_AIRCRAFT = ZOOM_LVL_NORMAL,

    25

	ZOOM_LVL_SHIP     = ZOOM_LVL_NORMAL,

    26

	ZOOM_LVL_TRAIN    = ZOOM_LVL_NORMAL,

    27

	ZOOM_LVL_ROADVEH  = ZOOM_LVL_NORMAL,

    28

	ZOOM_LVL_WORLD_SCREENSHOT = ZOOM_LVL_NORMAL,

    29

    30

	ZOOM_LVL_DETAIL   = ZOOM_LVL_OUT_2X, ///< All zoomlevels below or equal to this, will result in details on the screen, like road-work, ...

    31

    32

	ZOOM_LVL_MIN      = ZOOM_LVL_NORMAL,

    33

	ZOOM_LVL_MAX      = ZOOM_LVL_OUT_8X,

    34

};

    35

    36

extern ZoomLevel _saved_scrollpos_zoom;

    37

    38

DECLARE_POSTFIX_INCREMENT(ZoomLevel)

    39

    40

/**

    41

 * Scale by zoom level, usually shift left (when zoom > ZOOM_LVL_NORMAL)

    42

 * When shifting right, value is rounded up

    43

 * @param value value to shift

    44

 * @param zoom  zoom level to shift to

    45

 * @return shifted value

    46

 */

    47

static inline int ScaleByZoom(int value, ZoomLevel zoom)

    48

{

    49

	if (zoom == ZOOM_LVL_NORMAL) return value;

    50

	int izoom = zoom - ZOOM_LVL_NORMAL;

    51

	return (zoom > ZOOM_LVL_NORMAL) ? value << izoom : (value + (1 << -izoom) - 1) >> -izoom;

    52

}

    53

    54

/**

    55

 * Scale by zoom level, usually shift right (when zoom > ZOOM_LVL_NORMAL)

    56

 * When shifting right, value is rounded up

    57

 * @param value value to shift

    58

 * @param zoom  zoom level to shift to

    59

 * @return shifted value

    60

 */

    61

static inline int UnScaleByZoom(int value, ZoomLevel zoom)

    62

{

    63

	if (zoom == ZOOM_LVL_NORMAL) return value;

    64

	int izoom = zoom - ZOOM_LVL_NORMAL;

    65

	return (zoom > ZOOM_LVL_NORMAL) ? (value + (1 << izoom) - 1) >> izoom : value << -izoom;

    66

}

    67

    68

/**

    69

 * Scale by zoom level, usually shift left (when zoom > ZOOM_LVL_NORMAL)

    70

 * @param value value to shift

    71

 * @param zoom  zoom level to shift to

    72

 * @return shifted value

    73

 */

    74

static inline int ScaleByZoomLower(int value, ZoomLevel zoom)

    75

{

    76

	if (zoom == ZOOM_LVL_NORMAL) return value;

    77

	int izoom = zoom - ZOOM_LVL_NORMAL;

    78

	return (zoom > ZOOM_LVL_NORMAL) ? value << izoom : value >> -izoom;

    79

}

    80

    81

/**

    82

 * Scale by zoom level, usually shift right (when zoom > ZOOM_LVL_NORMAL)

    83

 * @param value value to shift

    84

 * @param zoom  zoom level to shift to

    85

 * @return shifted value

    86

 */

    87

static inline int UnScaleByZoomLower(int value, ZoomLevel zoom)

    88

{

    89

	if (zoom == ZOOM_LVL_NORMAL) return value;

    90

	int izoom = zoom - ZOOM_LVL_NORMAL;

    91

	return (zoom > ZOOM_LVL_NORMAL) ? value >> izoom : value << -izoom;

    92

}

    93

    94

#endif /* ZOOM_HPP */