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xterm.js/addons/xterm-addon-webgl/src/renderLayer/CursorRenderLayer.ts
T
2023-05-02 15:44:36 -07:00

376 lines
13 KiB
TypeScript

/**
* Copyright (c) 2017 The xterm.js authors. All rights reserved.
* @license MIT
*/
import { Terminal } from 'xterm';
import { BaseRenderLayer } from './BaseRenderLayer';
import { ICellData } from 'common/Types';
import { CellData } from 'common/buffer/CellData';
import { IRenderDimensions, IRequestRedrawEvent } from 'browser/renderer/shared/Types';
import { IEventEmitter } from 'common/EventEmitter';
import { ICoreBrowserService, IThemeService } from 'browser/services/Services';
import { ICoreService, IOptionsService } from 'common/services/Services';
import { toDisposable } from 'common/Lifecycle';
import { isFirefox } from 'common/Platform';
interface ICursorState {
x: number;
y: number;
isFocused: boolean;
style: string;
width: number;
}
/**
* The time between cursor blinks.
*/
const BLINK_INTERVAL = 600;
export class CursorRenderLayer extends BaseRenderLayer {
private _state: ICursorState;
private _cursorRenderers: {[key: string]: (terminal: Terminal, x: number, y: number, cell: ICellData) => void};
private _cursorBlinkStateManager: CursorBlinkStateManager | undefined;
private _cell: ICellData = new CellData();
constructor(
terminal: Terminal,
container: HTMLElement,
zIndex: number,
private _onRequestRefreshRowsEvent: IEventEmitter<IRequestRedrawEvent>,
coreBrowserService: ICoreBrowserService,
private readonly _coreService: ICoreService,
optionsService: IOptionsService,
themeService: IThemeService
) {
super(terminal, container, 'cursor', zIndex, true, coreBrowserService, optionsService, themeService);
this._state = {
x: 0,
y: 0,
isFocused: false,
style: '',
width: 0
};
this._cursorRenderers = {
'bar': this._renderBarCursor.bind(this),
'block': this._renderBlockCursor.bind(this),
'underline': this._renderUnderlineCursor.bind(this)
};
this._handleOptionsChanged(terminal);
this.register(optionsService.onOptionChange(() => this._handleOptionsChanged(terminal)));
this.register(toDisposable(() => {
this._cursorBlinkStateManager?.dispose();
this._cursorBlinkStateManager = undefined;
}));
}
public resize(terminal: Terminal, dim: IRenderDimensions): void {
super.resize(terminal, dim);
// Resizing the canvas discards the contents of the canvas so clear state
this._state = {
x: 0,
y: 0,
isFocused: false,
style: '',
width: 0
};
}
public reset(terminal: Terminal): void {
this._clearCursor();
this._cursorBlinkStateManager?.restartBlinkAnimation(terminal);
this._handleOptionsChanged(terminal);
}
public handleBlur(terminal: Terminal): void {
this._cursorBlinkStateManager?.pause();
this._onRequestRefreshRowsEvent.fire({ start: terminal.buffer.active.cursorY, end: terminal.buffer.active.cursorY });
}
public handleFocus(terminal: Terminal): void {
this._cursorBlinkStateManager?.resume(terminal);
this._onRequestRefreshRowsEvent.fire({ start: terminal.buffer.active.cursorY, end: terminal.buffer.active.cursorY });
}
private _handleOptionsChanged(terminal: Terminal): void {
if (terminal.options.cursorBlink) {
if (!this._cursorBlinkStateManager) {
this._cursorBlinkStateManager = new CursorBlinkStateManager(() => {
this._render(terminal, true);
}, this._coreBrowserService);
}
} else {
this._cursorBlinkStateManager?.dispose();
this._cursorBlinkStateManager = undefined;
}
// Request a refresh from the terminal as management of rendering is being
// moved back to the terminal
this._onRequestRefreshRowsEvent.fire({ start: terminal.buffer.active.cursorY, end: terminal.buffer.active.cursorY });
}
public handleCursorMove(terminal: Terminal): void {
this._cursorBlinkStateManager?.restartBlinkAnimation(terminal);
}
public handleGridChanged(terminal: Terminal, startRow: number, endRow: number): void {
if (!this._cursorBlinkStateManager || this._cursorBlinkStateManager.isPaused) {
this._render(terminal, false);
} else {
this._cursorBlinkStateManager.restartBlinkAnimation(terminal);
}
}
private _render(terminal: Terminal, triggeredByAnimationFrame: boolean): void {
// Don't draw the cursor if it's hidden
if (!this._coreService.isCursorInitialized || this._coreService.isCursorHidden) {
this._clearCursor();
return;
}
const cursorY = terminal.buffer.active.baseY + terminal.buffer.active.cursorY;
const viewportRelativeCursorY = cursorY - terminal.buffer.active.viewportY;
// in case cursor.x == cols adjust visual cursor to cols - 1
const cursorX = Math.min(terminal.buffer.active.cursorX, terminal.cols - 1);
// Don't draw the cursor if it's off-screen
if (viewportRelativeCursorY < 0 || viewportRelativeCursorY >= terminal.rows) {
this._clearCursor();
return;
}
// TODO: Need fast buffer API for loading cell
(terminal as any)._core.buffer.lines.get(cursorY).loadCell(cursorX, this._cell);
if (this._cell.content === undefined) {
return;
}
if (!this._coreBrowserService.isFocused) {
this._clearCursor();
this._ctx.save();
this._ctx.fillStyle = this._themeService.colors.cursor.css;
const cursorStyle = terminal.options.cursorStyle;
this._renderBlurCursor(terminal, cursorX, viewportRelativeCursorY, this._cell);
this._ctx.restore();
this._state.x = cursorX;
this._state.y = viewportRelativeCursorY;
this._state.isFocused = false;
this._state.style = cursorStyle!;
this._state.width = this._cell.getWidth();
return;
}
// Don't draw the cursor if it's blinking
if (this._cursorBlinkStateManager && !this._cursorBlinkStateManager.isCursorVisible) {
this._clearCursor();
return;
}
if (this._state) {
// The cursor is already in the correct spot, don't redraw
if (this._state.x === cursorX &&
this._state.y === viewportRelativeCursorY &&
this._state.isFocused === this._coreBrowserService.isFocused &&
this._state.style === terminal.options.cursorStyle &&
this._state.width === this._cell.getWidth()) {
return;
}
this._clearCursor();
}
this._ctx.save();
this._cursorRenderers[terminal.options.cursorStyle || 'block'](terminal, cursorX, viewportRelativeCursorY, this._cell);
this._ctx.restore();
this._state.x = cursorX;
this._state.y = viewportRelativeCursorY;
this._state.isFocused = false;
this._state.style = terminal.options.cursorStyle!;
this._state.width = this._cell.getWidth();
}
private _clearCursor(): void {
if (this._state) {
// Avoid potential rounding errors when browser is Firefox (#4487) or device pixel ratio is
// less than 1
if (isFirefox || this._coreBrowserService.dpr < 1) {
this._clearAll();
} else {
this._clearCells(this._state.x, this._state.y, this._state.width, 1);
}
this._state = {
x: 0,
y: 0,
isFocused: false,
style: '',
width: 0
};
}
}
private _renderBarCursor(terminal: Terminal, x: number, y: number, cell: ICellData): void {
this._ctx.save();
this._ctx.fillStyle = this._themeService.colors.cursor.css;
this._fillLeftLineAtCell(x, y, this._optionsService.rawOptions.cursorWidth);
this._ctx.restore();
}
private _renderBlockCursor(terminal: Terminal, x: number, y: number, cell: ICellData): void {
this._ctx.save();
this._ctx.fillStyle = this._themeService.colors.cursor.css;
this._fillCells(x, y, cell.getWidth(), 1);
this._ctx.fillStyle = this._themeService.colors.cursorAccent.css;
this._fillCharTrueColor(terminal, cell, x, y);
this._ctx.restore();
}
private _renderUnderlineCursor(terminal: Terminal, x: number, y: number, cell: ICellData): void {
this._ctx.save();
this._ctx.fillStyle = this._themeService.colors.cursor.css;
this._fillBottomLineAtCells(x, y);
this._ctx.restore();
}
private _renderBlurCursor(terminal: Terminal, x: number, y: number, cell: ICellData): void {
this._ctx.save();
this._ctx.strokeStyle = this._themeService.colors.cursor.css;
this._strokeRectAtCell(x, y, cell.getWidth(), 1);
this._ctx.restore();
}
}
class CursorBlinkStateManager {
public isCursorVisible: boolean;
private _animationFrame: number | undefined;
private _blinkStartTimeout: number | undefined;
private _blinkInterval: number | undefined;
/**
* The time at which the animation frame was restarted, this is used on the
* next render to restart the timers so they don't need to restart the timers
* multiple times over a short period.
*/
private _animationTimeRestarted: number | undefined;
constructor(
private _renderCallback: () => void,
private _coreBrowserService: ICoreBrowserService
) {
this.isCursorVisible = true;
if (this._coreBrowserService.isFocused) {
this._restartInterval();
}
}
public get isPaused(): boolean { return !(this._blinkStartTimeout || this._blinkInterval); }
public dispose(): void {
if (this._blinkInterval) {
this._coreBrowserService.window.clearInterval(this._blinkInterval);
this._blinkInterval = undefined;
}
if (this._blinkStartTimeout) {
this._coreBrowserService.window.clearTimeout(this._blinkStartTimeout);
this._blinkStartTimeout = undefined;
}
if (this._animationFrame) {
this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
this._animationFrame = undefined;
}
}
public restartBlinkAnimation(terminal: Terminal): void {
if (this.isPaused) {
return;
}
// Save a timestamp so that the restart can be done on the next interval
this._animationTimeRestarted = Date.now();
// Force a cursor render to ensure it's visible and in the correct position
this.isCursorVisible = true;
if (!this._animationFrame) {
this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
this._renderCallback();
this._animationFrame = undefined;
});
}
}
private _restartInterval(timeToStart: number = BLINK_INTERVAL): void {
// Clear any existing interval
if (this._blinkInterval) {
this._coreBrowserService.window.clearInterval(this._blinkInterval);
this._blinkInterval = undefined;
}
// Setup the initial timeout which will hide the cursor, this is done before
// the regular interval is setup in order to support restarting the blink
// animation in a lightweight way (without thrashing clearInterval and
// setInterval).
this._blinkStartTimeout = this._coreBrowserService.window.setTimeout(() => {
// Check if another animation restart was requested while this was being
// started
if (this._animationTimeRestarted) {
const time = BLINK_INTERVAL - (Date.now() - this._animationTimeRestarted);
this._animationTimeRestarted = undefined;
if (time > 0) {
this._restartInterval(time);
return;
}
}
// Hide the cursor
this.isCursorVisible = false;
this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
this._renderCallback();
this._animationFrame = undefined;
});
// Setup the blink interval
this._blinkInterval = this._coreBrowserService.window.setInterval(() => {
// Adjust the animation time if it was restarted
if (this._animationTimeRestarted) {
// calc time diff
// Make restart interval do a setTimeout initially?
const time = BLINK_INTERVAL - (Date.now() - this._animationTimeRestarted);
this._animationTimeRestarted = undefined;
this._restartInterval(time);
return;
}
// Invert visibility and render
this.isCursorVisible = !this.isCursorVisible;
this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
this._renderCallback();
this._animationFrame = undefined;
});
}, BLINK_INTERVAL);
}, timeToStart);
}
public pause(): void {
this.isCursorVisible = true;
if (this._blinkInterval) {
this._coreBrowserService.window.clearInterval(this._blinkInterval);
this._blinkInterval = undefined;
}
if (this._blinkStartTimeout) {
this._coreBrowserService.window.clearTimeout(this._blinkStartTimeout);
this._blinkStartTimeout = undefined;
}
if (this._animationFrame) {
this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
this._animationFrame = undefined;
}
}
public resume(terminal: Terminal): void {
// Clear out any existing timers just in case
this.pause();
this._animationTimeRestarted = undefined;
this._restartInterval();
this.restartBlinkAnimation(terminal);
}
}