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DrawShared

kas_core::draw

Trait DrawShared 

Source 
pub trait DrawShared {
    // Required methods
    fn image_alloc(
        &mut self,
        format: ImageFormat,
        size: Size,
    ) -> Result<ImageHandle, AllocError>;
    fn image_upload(
        &mut self,
        handle: &ImageHandle,
        data: &[u8],
    ) -> Result<ActionRedraw, UploadError>;
    fn image_free(&mut self, handle: ImageHandle);
    fn image_size(&self, handle: &ImageHandle) -> Option<Size>;
}
Expand description

Interface over SharedState

All methods concern management of resources for drawing.

Required Methods§

Source

fn image_alloc( &mut self, format: ImageFormat, size: Size, ) -> Result<ImageHandle, AllocError>

Allocate an image

Use SharedState::image_upload to set contents of the new image.

Source

fn image_upload( &mut self, handle: &ImageHandle, data: &[u8], ) -> Result<ActionRedraw, UploadError>

Upload an image to the GPU

This should be called at least once on each image before display. May be called again to update the image contents.

The handle must point to an existing allocation of size (w, h) and with image format format with b bytes-per-pixel such that data.len() == b * w * h. Data must be in row-major order.

On success, this returns an ActionRedraw to indicate that any widgets using this image will require a redraw.

Source

fn image_free(&mut self, handle: ImageHandle)

Potentially free an image

The input handle is consumed. If this reduces its reference count to zero, then the image is freed.

Source

fn image_size(&self, handle: &ImageHandle) -> Option<Size>

Get the size of an image

Implementors§