Support selection foreground in webgl

Part of #3810

addons/xterm-addon-webgl/src/WebglRenderer.ts

@@ -398,6 +398,9 @@ export class WebglRenderer extends Disposable implements IRenderer {
     // Apply the selection color if needed
     if (this._isCellSelected(x, y)) {
       bgOverride = this._colors.selectionOpaque.rgba >> 8 & 0xFFFFFF;
+      if (this._colors.selectionForeground) {
+        fgOverride = this._colors.selectionForeground.rgba >> 8 && 0xFFFFFF;
+      }
     }
 
     // Apply decorations on the top layer

addons/xterm-addon-webgl/src/atlas/CharAtlasUtils.ts

@@ -23,6 +23,7 @@ export function generateConfig(scaledCellWidth: number, scaledCellHeight: number
     cursorAccent: NULL_COLOR,
     selectionTransparent: NULL_COLOR,
     selectionOpaque: NULL_COLOR,
+    selectionForeground: NULL_COLOR,
     // For the static char atlas, we only use the first 16 colors, but we need all 256 for the
     // dynamic character atlas.
     ansi: colors.ansi.slice(),

src/browser/ColorManager.ts

@@ -104,6 +104,7 @@ export class ColorManager implements IColorManager {
       cursorAccent: DEFAULT_CURSOR_ACCENT,
       selectionTransparent: DEFAULT_SELECTION,
       selectionOpaque: color.blend(DEFAULT_BACKGROUND, DEFAULT_SELECTION),
+      selectionForeground: undefined,
       ansi: DEFAULT_ANSI_COLORS.slice(),
       contrastCache: this._contrastCache
     };
@@ -128,6 +129,15 @@ export class ColorManager implements IColorManager {
     this.colors.cursorAccent = this._parseColor(theme.cursorAccent, DEFAULT_CURSOR_ACCENT, true);
     this.colors.selectionTransparent = this._parseColor(theme.selection, DEFAULT_SELECTION, true);
     this.colors.selectionOpaque = color.blend(this.colors.background, this.colors.selectionTransparent);
+    const nullColor: IColor = {
+      css: '',
+      rgba: 0
+    };
+    this.colors.selectionForeground = theme.selectionForeground ? this._parseColor(theme.selectionForeground, nullColor) : undefined;
+    if (this.colors.selectionForeground === nullColor) {
+      this.colors.selectionForeground = undefined;
+    }
+
     /**
      * If selection color is opaque, blend it with background with 0.3 opacity
      * Issue #2737

src/browser/Types.d.ts

@@ -120,6 +120,7 @@ export interface IColorSet {
   selectionTransparent: IColor;
   /** The selection blended on top of background. */
   selectionOpaque: IColor;
+  selectionForeground: IColor | undefined;
   ansi: IColor[];
   contrastCache: IColorContrastCache;
 }

src/common/services/Services.ts

@@ -259,6 +259,7 @@ export interface ITheme {
   cursor?: string;
   cursorAccent?: string;
   selection?: string;
+  selectionForeground?: string;
   black?: string;
   red?: string;
   green?: string;

typings/xterm.d.ts

@@ -288,6 +288,8 @@ declare module 'xterm' {
     cursorAccent?: string;
     /** The selection background color (can be transparent) */
     selection?: string;
+    /** The selection foreground color */
+    selectionForeground?: string;
     /** ANSI black (eg. `\x1b[30m`) */
     black?: string;
     /** ANSI red (eg. `\x1b[31m`) */