115 lines
3.9 KiB
Go
115 lines
3.9 KiB
Go
package tomo
|
|
|
|
import "image"
|
|
import "errors"
|
|
import "image/draw"
|
|
import "image/color"
|
|
// import "git.tebibyte.media/sashakoshka/tomo/iterator"
|
|
|
|
// Image represents a simple image buffer that fulfills the image.Image
|
|
// interface while also having methods that do away with the use of the
|
|
// color.Color interface to facilitate more efficient drawing. This interface
|
|
// can be easily satisfied using an image.RGBA struct.
|
|
type Image interface {
|
|
image.Image
|
|
RGBAAt (x, y int) (c color.RGBA)
|
|
}
|
|
|
|
// Canvas is like Image but also requires a SetRGBA method. This interface can
|
|
// be easily satisfied using an image.RGBA struct.
|
|
type Canvas interface {
|
|
draw.Image
|
|
RGBAAt (x, y int) (c color.RGBA)
|
|
SetRGBA (x, y int, c color.RGBA)
|
|
}
|
|
|
|
// Element represents a basic on-screen object.
|
|
type Element interface {
|
|
// Element must implement the Image interface. Elements should start out
|
|
// with a completely blank image buffer, and only set its size and draw
|
|
// on it for the first time when sent an EventResize event.
|
|
Image
|
|
|
|
// Handle handles an event, propagating it to children if necessary.
|
|
Handle (event Event)
|
|
|
|
// Selectable returns whether this element can be selected. If this
|
|
// element contains other selectable elements, it must return true.
|
|
Selectable () (bool)
|
|
|
|
// SetDrawCallback sets a function to be called when a part of the
|
|
// element's surface is updated. The updated region will be passed to
|
|
// the callback as a sub-image.
|
|
SetDrawCallback (draw func (region Image))
|
|
|
|
// SetMinimumSizeChangeCallback sets a function to be called when the
|
|
// element's minimum width and/or height changes. When this function is
|
|
// called, the element will have already been resized and there is no
|
|
// need to send it a resize event.
|
|
SetMinimumSizeChangeCallback (notify func (width, height int))
|
|
|
|
// MinimumWidth specifies the minimum amount of pixels this element's
|
|
// width may be set to. If the element is resized to an amount smaller
|
|
// that MinimumWidth, it will instead set its width to MinimumWidth.
|
|
MinimumWidth () (minimum int)
|
|
|
|
// MinimumHeight specifies the minimum amount of pixels this element's
|
|
// height may be set to. If the element is resized to an amount smaller
|
|
// that MinimumHeight, it will instead set its height to MinimumHeight.
|
|
MinimumHeight () (minimum int)
|
|
}
|
|
|
|
// Window represents a top-level container generated by the currently running
|
|
// backend. It can contain a single element. It is hidden by default, and must
|
|
// be explicitly shown with the Show() method. If it contains no element, it
|
|
// displays a black (or transprent) background.
|
|
type Window interface {
|
|
Element
|
|
Adopt (child Element)
|
|
Child () (child Element)
|
|
SetTitle (title string)
|
|
SetIcon (sizes []image.Image)
|
|
Show ()
|
|
Hide ()
|
|
Close ()
|
|
OnClose (func ())
|
|
}
|
|
|
|
var backend Backend
|
|
|
|
// Run initializes a backend, calls the callback function, and begins the event
|
|
// loop in that order. This function does not return until Stop() is called, or
|
|
// the backend experiences a fatal error.
|
|
func Run (callback func ()) (err error) {
|
|
backend, err = instantiateBackend()
|
|
if callback != nil { callback() }
|
|
err = backend.Run()
|
|
backend = nil
|
|
return
|
|
}
|
|
|
|
// Stop gracefully stops the event loop and shuts the backend down. Call this
|
|
// before closing your application.
|
|
func Stop () {
|
|
if backend != nil { backend.Stop() }
|
|
}
|
|
|
|
// Do executes the specified callback within the main thread as soon as
|
|
// possible. This function can be safely called from other threads.
|
|
func Do (callback func ()) {
|
|
|
|
}
|
|
|
|
// NewWindow creates a new window using the current backend, and returns it as a
|
|
// Window. If the window could not be created, an error is returned explaining
|
|
// why. If this function is called without a running backend, an error is
|
|
// returned as well.
|
|
func NewWindow (width, height int) (window Window, err error) {
|
|
if backend == nil {
|
|
err = errors.New("no backend is running.")
|
|
return
|
|
}
|
|
window, err = backend.NewWindow(width, height)
|
|
return
|
|
}
|