diff options
Diffstat (limited to 'src/zoom.hpp')
-rw-r--r-- | src/zoom.hpp | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/src/zoom.hpp b/src/zoom.hpp index e0e7cc7a0..f924b362f 100644 --- a/src/zoom.hpp +++ b/src/zoom.hpp @@ -32,6 +32,13 @@ enum ZoomLevel { extern ZoomLevel _saved_scrollpos_zoom; +/** + * Scale by zoom level, usually shift left (when zoom > ZOOM_LVL_NORMAL) + * When shifting right, value is rounded up + * @param value value to shift + * @param zoom zoom level to shift to + * @return shifted value + */ static inline int ScaleByZoom(int value, ZoomLevel zoom) { if (zoom == ZOOM_LVL_NORMAL) return value; @@ -39,6 +46,13 @@ static inline int ScaleByZoom(int value, ZoomLevel zoom) return (zoom > ZOOM_LVL_NORMAL) ? value << izoom : (value + (1 << -izoom) - 1) >> -izoom; } +/** + * Scale by zoom level, usually shift right (when zoom > ZOOM_LVL_NORMAL) + * When shifting right, value is rounded up + * @param value value to shift + * @param zoom zoom level to shift to + * @return shifted value + */ static inline int UnScaleByZoom(int value, ZoomLevel zoom) { if (zoom == ZOOM_LVL_NORMAL) return value; @@ -46,4 +60,30 @@ static inline int UnScaleByZoom(int value, ZoomLevel zoom) return (zoom > ZOOM_LVL_NORMAL) ? (value + (1 << izoom) - 1) >> izoom : value << -izoom; } +/** + * Scale by zoom level, usually shift left (when zoom > ZOOM_LVL_NORMAL) + * @param value value to shift + * @param zoom zoom level to shift to + * @return shifted value + */ +static inline int ScaleByZoomLower(int value, ZoomLevel zoom) +{ + if (zoom == ZOOM_LVL_NORMAL) return value; + int izoom = (int)zoom - (int)ZOOM_LVL_NORMAL; + return (zoom > ZOOM_LVL_NORMAL) ? value << izoom : value >> -izoom; +} + +/** + * Scale by zoom level, usually shift right (when zoom > ZOOM_LVL_NORMAL) + * @param value value to shift + * @param zoom zoom level to shift to + * @return shifted value + */ +static inline int UnScaleByZoomLower(int value, ZoomLevel zoom) +{ + if (zoom == ZOOM_LVL_NORMAL) return value; + int izoom = (int)zoom - (int)ZOOM_LVL_NORMAL; + return (zoom > ZOOM_LVL_NORMAL) ? value >> izoom : value << -izoom; +} + #endif /* ZOOM_HPP */ |