doodle/lib/events/events.go
Noah Petherbridge c8620f871e Drawing Strokes and Undo/Redo Functionality
* Add new pkg/drawtool with utilities to abstract away drawing actions
  into Strokes and track undo/redo History for them.
* The freehand Pencil tool in EditorMode has been refactored to create a
  Stroke of Shape=Freehand and queue up its world pixels there instead
  of directly modifying the level chunker in real time. When the mouse
  button is released, the freehand Stroke is committed to the level
  chunker and added to the UndoHistory.
* UndoHistory is (temporarily) stored with the level.Level so it can
  survive trips to PlayScene and back, but is not stored as JSON on
  disk.
* Ctrl-Z and Ctrl-Y in EditorMode for undo and redo, respectively.
2019-07-03 16:25:23 -07:00

93 lines
1.8 KiB
Go

// Package events manages mouse and keyboard SDL events for Doodle.
package events
import (
"strings"
)
// State keeps track of event states.
type State struct {
// Mouse buttons.
Button1 *BoolTick // left
Button2 *BoolTick // right
Button3 *BoolTick // middle
EscapeKey *BoolTick
EnterKey *BoolTick
ShiftActive *BoolTick
ControlActive *BoolTick
KeyName *StringTick
Up *BoolTick
Left *BoolTick
Right *BoolTick
Down *BoolTick
// Cursor positions.
CursorX *Int32Tick
CursorY *Int32Tick
// Window events: window has changed size.
Resized *BoolTick
}
// New creates a new event state manager.
func New() *State {
return &State{
Button1: &BoolTick{},
Button2: &BoolTick{},
Button3: &BoolTick{},
EscapeKey: &BoolTick{},
EnterKey: &BoolTick{},
ShiftActive: &BoolTick{},
ControlActive: &BoolTick{},
KeyName: &StringTick{},
Up: &BoolTick{},
Left: &BoolTick{},
Right: &BoolTick{},
Down: &BoolTick{},
CursorX: &Int32Tick{},
CursorY: &Int32Tick{},
Resized: &BoolTick{},
}
}
// ReadKey returns the normalized key symbol being pressed,
// taking the Shift key into account. QWERTY keyboard only, probably.
func (ev *State) ReadKey() string {
if key := ev.KeyName.Read(); key != "" {
if ev.ShiftActive.Pressed() {
if symbol, ok := shiftMap[key]; ok {
return symbol
}
return strings.ToUpper(key)
}
return key
}
return ""
}
// shiftMap maps keys to their Shift versions.
var shiftMap = map[string]string{
"`": "~",
"1": "!",
"2": "@",
"3": "#",
"4": "$",
"5": "%",
"6": "^",
"7": "&",
"8": "*",
"9": "(",
"0": ")",
"-": "_",
"=": "+",
"[": "{",
"]": "}",
`\`: "|",
";": ":",
`'`: `"`,
",": "<",
".": ">",
"/": "?",
}