Struct qt_widgets::q_graphics_item::CacheMode

#[repr(transparent)]pub struct CacheMode(_);

This enum describes QGraphicsItem's cache modes. Caching is used to speed up rendering by allocating and rendering to an off-screen pixel buffer, which can be reused when the item requires redrawing. For some paint devices, the cache is stored directly in graphics memory, which makes rendering very quick.

C++ enum: QGraphicsItem::CacheMode.

C++ documentation:

This enum describes QGraphicsItem's cache modes. Caching is used to speed up rendering by allocating and rendering to an off-screen pixel buffer, which can be reused when the item requires redrawing. For some paint devices, the cache is stored directly in graphics memory, which makes rendering very quick.

This enum was introduced or modified in Qt 4.4.

See also QGraphicsItem::setCacheMode().

Methods

impl CacheMode

pub fn to_int(&self) -> c_int

impl CacheMode

pub const NoCache: CacheMode

The default; all item caching is disabled. QGraphicsItem::paint() is called every time the item needs redrawing. (C++ enum variant: NoCache = 0)

pub const ItemCoordinateCache: CacheMode

Caching is enabled for the item's logical (local) coordinate system. QGraphicsItem creates an off-screen pixel buffer with a configurable size / resolution that you can pass to QGraphicsItem::setCacheMode(). Rendering quality will typically degrade, depending on the resolution of the cache and the item transformation. The first time the item is redrawn, it will render itself into the cache, and the cache is then reused for every subsequent expose. The cache is also reused as the item is transformed. To adjust the resolution of the cache, you can call setCacheMode() again. (C++ enum variant: ItemCoordinateCache = 1)

pub const DeviceCoordinateCache: CacheMode

Caching is enabled at the paint device level, in device coordinates. This mode is for items that can move, but are not rotated, scaled or sheared. If the item is transformed directly or indirectly, the cache will be regenerated automatically. Unlike ItemCoordinateCacheMode, DeviceCoordinateCache always renders at maximum quality. (C++ enum variant: DeviceCoordinateCache = 2)

Trait Implementations

impl Clone for CacheMode

fn clone(&self) -> CacheMode

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for CacheMode

impl Debug for CacheMode

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Eq for CacheMode

impl From<CacheMode> for c_int

fn from(value: CacheMode) -> Self

Performs the conversion.

impl From<i32> for CacheMode

fn from(value: c_int) -> Self

Performs the conversion.

impl PartialEq<CacheMode> for CacheMode

fn eq(&self, other: &CacheMode) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &CacheMode) -> bool

This method tests for !=.

impl StructuralEq for CacheMode

impl StructuralPartialEq for CacheMode