Documentation
¶
Overview ¶
Package pelcanvas provides mouse event handling for the pixel canvas.
Package pelcanvas provides canvas operations for zooming and panning.
Package pelcanvas provides the pixel canvas widget for the Pel pixel art editor.
Package pelcanvas provides rendering functionality for the pixel canvas widget.
Index ¶
- Constants
- Variables
- func NewBlankImage(cols, rows int, c color.Color) (image.Image, error)
- type PelCanvas
- func (pelCanvas *PelCanvas) Bounds() image.Rectangle
- func (pelCanvas *PelCanvas) Clear(c color.Color) error
- func (pelCanvas *PelCanvas) CreateRenderer() fyne.WidgetRenderer
- func (pelCanvas *PelCanvas) GetPixelColor(x, y int) (color.Color, error)
- func (pelCanvas *PelCanvas) GetZoomLevel() int
- func (pelCanvas *PelCanvas) InBounds(pos fyne.Position) bool
- func (pelCanvas *PelCanvas) LoadImage(img image.Image) error
- func (pelCanvas *PelCanvas) MouseDown(ev *desktop.MouseEvent)
- func (pelCanvas *PelCanvas) MouseIn(ev *desktop.MouseEvent)
- func (pelCanvas *PelCanvas) MouseMoved(ev *desktop.MouseEvent)
- func (pelCanvas *PelCanvas) MouseOut()
- func (pelCanvas *PelCanvas) MouseToCanvasXY(ev *desktop.MouseEvent) (*int, *int)
- func (pelCanvas *PelCanvas) MouseUp(ev *desktop.MouseEvent)
- func (pelCanvas *PelCanvas) NewDrawing(cols, rows int) error
- func (pelCanvas *PelCanvas) Pan(previousCoord, currentCoord fyne.PointEvent)
- func (pelCanvas *PelCanvas) ResetView()
- func (pelCanvas *PelCanvas) Scrolled(ev *fyne.ScrollEvent)
- func (pelCanvas *PelCanvas) SetColor(c color.Color, x, y int) error
- func (pelCanvas *PelCanvas) TryPan(previousCoord *fyne.PointEvent, ev *desktop.MouseEvent)
- func (pelCanvas *PelCanvas) ZoomIn()
- func (pelCanvas *PelCanvas) ZoomOut()
- func (pelCanvas *PelCanvas) ZoomToFit(windowSize fyne.Size)
- type PelCanvasMouseState
- type PelCanvasRenderer
- func (renderer *PelCanvasRenderer) Destroy()
- func (renderer *PelCanvasRenderer) Layout(size fyne.Size)
- func (renderer *PelCanvasRenderer) MinSize() fyne.Size
- func (renderer *PelCanvasRenderer) Objects() []fyne.CanvasObject
- func (renderer *PelCanvasRenderer) Refresh()
- func (renderer *PelCanvasRenderer) SetCursor(objects []fyne.CanvasObject)
Constants ¶
const ( MinPixelSize = 2 // Minimum size for a pixel in screen pixels MaxPixelSize = 100 // Maximum size for a pixel in screen pixels DefaultPixelSize = 10 // Default pixel size when reset ScaleStep = 1 // Amount to change pixel size per scroll event )
Canvas operation constants
const ( BorderStrokeWidth = 2 DefaultGrayValue = 128 )
Canvas rendering constants
const ( BorderLeft = 0 BorderTop = 1 BorderRight = 2 BorderBottom = 3 BorderCount = 4 )
Border position indices
const (
ScrollSensitivity = 1 // Multiplier for scroll events
)
Mouse interaction constants
Variables ¶
var ( BorderColor = color.NRGBA{R: 100, G: 100, B: 100, A: 255} DefaultCanvasGray = color.NRGBA{R: DefaultGrayValue, G: DefaultGrayValue, B: DefaultGrayValue, A: 255} )
Default colors
Functions ¶
Types ¶
type PelCanvas ¶
type PelCanvas struct {
widget.BaseWidget
apptype.PelCanvasConfig
PixelData image.Image
// contains filtered or unexported fields
}
PelCanvas is the main canvas widget for drawing pixel art
func NewPelCanvas ¶
func NewPelCanvas(state *apptype.State, config apptype.PelCanvasConfig) *PelCanvas
NewPelCanvas creates a new pixel canvas with the given configuration
func (*PelCanvas) CreateRenderer ¶
func (pelCanvas *PelCanvas) CreateRenderer() fyne.WidgetRenderer
CreateRenderer creates the renderer for the canvas widget
func (*PelCanvas) GetPixelColor ¶
GetPixelColor returns the color at the specified pixel coordinates
func (*PelCanvas) GetZoomLevel ¶
GetZoomLevel returns the current zoom level as a percentage 100% = DefaultPixelSize
func (*PelCanvas) LoadImage ¶
LoadImage loads an image into the canvas The canvas dimensions will be adjusted to match the image
func (*PelCanvas) MouseDown ¶
func (pelCanvas *PelCanvas) MouseDown(ev *desktop.MouseEvent)
MouseDown handles mouse button press events
func (*PelCanvas) MouseIn ¶
func (pelCanvas *PelCanvas) MouseIn(ev *desktop.MouseEvent)
MouseIn handles mouse entering the canvas area
func (*PelCanvas) MouseMoved ¶
func (pelCanvas *PelCanvas) MouseMoved(ev *desktop.MouseEvent)
MouseMoved handles mouse movement events for drawing and cursor updates
func (*PelCanvas) MouseOut ¶
func (pelCanvas *PelCanvas) MouseOut()
MouseOut handles mouse leaving the canvas area
func (*PelCanvas) MouseToCanvasXY ¶
func (pelCanvas *PelCanvas) MouseToCanvasXY(ev *desktop.MouseEvent) (*int, *int)
MouseToCanvasXY converts mouse event coordinates to canvas pixel coordinates Returns nil pointers if the coordinates are outside the canvas
func (*PelCanvas) MouseUp ¶
func (pelCanvas *PelCanvas) MouseUp(ev *desktop.MouseEvent)
MouseUp handles mouse button release events
func (*PelCanvas) NewDrawing ¶
NewDrawing creates a new blank drawing with the specified dimensions
func (*PelCanvas) Pan ¶
func (pelCanvas *PelCanvas) Pan(previousCoord, currentCoord fyne.PointEvent)
Pan shifts the canvas offset based on mouse movement This allows the user to move the canvas around the viewport
func (*PelCanvas) ResetView ¶
func (pelCanvas *PelCanvas) ResetView()
ResetView resets the canvas to default zoom and position
func (*PelCanvas) Scrolled ¶
func (pelCanvas *PelCanvas) Scrolled(ev *fyne.ScrollEvent)
Scrolled handles mouse scroll events for zooming the canvas
func (*PelCanvas) SetColor ¶
SetColor sets the color of a pixel at the specified coordinates Returns an error if the coordinates are out of bounds or if the operation fails
func (*PelCanvas) TryPan ¶
func (pelCanvas *PelCanvas) TryPan(previousCoord *fyne.PointEvent, ev *desktop.MouseEvent)
TryPan attempts to pan the canvas if the middle mouse button is pressed
func (*PelCanvas) ZoomIn ¶
func (pelCanvas *PelCanvas) ZoomIn()
ZoomIn increases the pixel size by one step
type PelCanvasMouseState ¶
type PelCanvasMouseState struct {
// contains filtered or unexported fields
}
PelCanvasMouseState tracks the mouse state for pan/drag operations
type PelCanvasRenderer ¶
type PelCanvasRenderer struct {
// contains filtered or unexported fields
}
PelCanvasRenderer handles the rendering of the pixel canvas widget
func (*PelCanvasRenderer) Destroy ¶
func (renderer *PelCanvasRenderer) Destroy()
Destroy cleans up any resources used by the renderer
func (*PelCanvasRenderer) Layout ¶
func (renderer *PelCanvasRenderer) Layout(size fyne.Size)
Layout positions and sizes all canvas objects
func (*PelCanvasRenderer) MinSize ¶
func (renderer *PelCanvasRenderer) MinSize() fyne.Size
MinSize returns the minimum size required to display the canvas
func (*PelCanvasRenderer) Objects ¶
func (renderer *PelCanvasRenderer) Objects() []fyne.CanvasObject
Objects returns all canvas objects that need to be rendered
func (*PelCanvasRenderer) Refresh ¶
func (renderer *PelCanvasRenderer) Refresh()
Refresh updates the renderer with the latest canvas state
func (*PelCanvasRenderer) SetCursor ¶
func (renderer *PelCanvasRenderer) SetCursor(objects []fyne.CanvasObject)
SetCursor updates the cursor objects to be displayed
Source Files
Directories