Fyne API "canvas.Raster"

canvas.Raster


import "fyne.io/fyne/v2/canvas"

Usage

type Raster

type Raster struct {

	// Render the raster image from code
	Generator func(w, h int) image.Image

	// Set a translucency value > 0.0 to fade the raster
	Translucency float64
	// Specify the type of scaling interpolation applied to the raster if it is not full-size
	// Since: 1.4.1
	ScaleMode ImageScale
}

Raster describes a raster image area that can render in a Fyne canvas

func NewRaster

func NewRaster(generate func(w, h int) image.Image) *Raster

NewRaster returns a new Image instance that is rendered dynamically using the specified generate function. Images returned from this method should draw dynamically to fill the width and height parameters passed to pixelColor.

func NewRasterFromImage

func NewRasterFromImage(img image.Image) *Raster

NewRasterFromImage returns a new Raster instance that is rendered from the Go image.Image passed in. Rasters returned from this method will map pixel for pixel to the screen starting img.Bounds().Min pixels from the top left of the canvas object. Truncates rather than scales the image. If smaller than the target space, the image will be padded with zero-pixels to the target size.

func NewRasterWithPixels

func NewRasterWithPixels(pixelColor func(x, y, w, h int) color.Color) *Raster

NewRasterWithPixels returns a new Image instance that is rendered dynamically by iterating over the specified pixelColor function for each x, y pixel. Images returned from this method should draw dynamically to fill the width and height parameters passed to pixelColor.

func (*Raster) Alpha

func (r *Raster) Alpha() float64

Alpha is a convenience function that returns the alpha value for a raster based on its Translucency value. The result is 1.0 - Translucency.

func (*Raster) Hide

func (r *Raster) Hide()

Hide will set this raster to not be visible

func (*Raster) MinSize

func (o *Raster) MinSize() fyne.Size

MinSize returns the specified minimum size, if set, or {1, 1} otherwise.

func (*Raster) Move

func (r *Raster) Move(pos fyne.Position)

Move the raster to a new position, relative to its parent / canvas

func (*Raster) Position

func (o *Raster) Position() fyne.Position

Position gets the current position of this canvas object, relative to its parent.

func (*Raster) Refresh

func (r *Raster) Refresh()

Refresh causes this raster to be redrawn with its configured state.

func (*Raster) Resize

func (r *Raster) Resize(s fyne.Size)

Resize on a raster image causes the new size to be set and then calls Refresh. This causes the underlying data to be recalculated and a new output to be drawn.

func (*Raster) SetMinSize

func (o *Raster) SetMinSize(size fyne.Size)

SetMinSize specifies the smallest size this object should be.

func (*Raster) Show

func (o *Raster) Show()

Show will set this object to be visible.

func (*Raster) Size

func (o *Raster) Size() fyne.Size

Size returns the current size of this canvas object.

func (*Raster) Visible

func (o *Raster) Visible() bool

Visible returns true if this object is visible, false otherwise.