Struct Spritesheet

pub struct Spritesheet { /* private fields */ }

Holds a texture for rendering.

This struct is safe to clone in order to use elsewhere: the only data held by this struct is a handle to the internal draw call. Currently, it is not possible to delete draw calls, and the only way to create a new one is by using the SpritesheetBuilder.

Example

let mut ctx = fae::Context::new();
use fae::SpritesheetBuilder;

// Creating the spritesheet:
let spritesheet = SpritesheetBuilder::default()
    .image(an_image)
    .alpha_blending(false)
    .build(&mut ctx);

// Later, in rendering code:
let mut ctx = ctx.start_frame(width, height, dpi_factor);
spritesheet.draw(&mut ctx)
    .coordinates((100.0, 100.0, 16.0, 16.0))
    .texture_coordinates((0, 0, 16, 16))
    .finish();

Implementations

impl Spritesheet

pub fn draw<'a, 'b>( &'b self, ctx: &'a mut GraphicsContext<'_>, ) -> Sprite<'a, 'b>

Creates a Sprite struct, a builder struct which defines the action “draw a sprite from this spritesheet onto the screen.” To “execute” the builder, call finish(). The parameters are set using the builder pattern.

Optimization tips

• If possible, make your textures without using alpha values between 1 and 0 (ie. use only 100% and 0% opacity), and disable alpha_blending in SpritesheetBuilder. These kinds of sprites can be drawn much more efficiently when it comes to overdraw.

• If alpha_blending is disabled, draw the sprites in front first. This way you’ll avoid rendering over already drawn pixels. If you’re rendering lots of sprites, this is a good place to start optimizing.

  • Note: if alpha_blending is enabled, the you should draw the sprites in the back first, to ensure correct rendering.

pub fn upload_texture_region<R: Into<Rect>>( &self, ctx: &mut GraphicsContext<'_>, region: R, image: &Image, ) -> bool

Upload an image into the specified region in the spritesheet.

As the inner values of region will be floored before use, it is recommended to use a (i32, i32, i32, i32) as the region parameter to ensure expected behavior.

If the width and height of region and image don’t match, or the region isn’t completely contained within the texture, this function will do nothing and return false.

See also: Image::with_null_texture.

pub fn resize_texture( &self, ctx: &mut GraphicsContext<'_>, new_width: i32, new_height: i32, ) -> bool

Resize the spritesheet texture to a new width and height, which must be equal or greater than the original dimensions. The previous contents of the texture are preserved in the origin corner of the texture.

If new_width is less than the current width, or new_height is less than the current height, this function will do nothing and return false.

See also: Spritesheet::upload_texture_region.

Trait Implementations

impl Clone for Spritesheet

fn clone(&self) -> Spritesheet

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Spritesheet

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

Formats the value using the given formatter.