Added DrawableTextUnderColor.

src/drawables/drawable-text-under-color.ts

@@ -0,0 +1,18 @@
+// Copyright Dirk Lemstra https://github.com/dlemstra/magick-wasm.
+// Licensed under the Apache License, Version 2.0.
+
+import { IDrawable } from './drawable';
+import { IDrawingWand } from './drawing-wand';
+import { MagickColor } from '../magick-color';
+
+export class DrawableTextUnderColor implements IDrawable {
+    private readonly _color: MagickColor;
+
+    constructor(color: MagickColor) {
+        this._color = color;
+    }
+
+    draw(wand: IDrawingWand): void {
+        wand.textUnderColor(this._color);
+    }
+}

src/drawables/drawing-wand.ts

@@ -33,6 +33,7 @@ export interface IDrawingWand extends IDisposable {
     textInterlineSpacing(value: number): void;
     textInterwordspacing(value: number): void;
     textKerning(value: number): void;
+    textUnderColor(value: MagickColor): void;
 }
 
 export class DrawingWand extends NativeInstance implements IDrawingWand {
@@ -151,6 +152,14 @@ export class DrawingWand extends NativeInstance implements IDrawingWand {
         });
     }
 
+    textUnderColor(value: MagickColor): void {
+        Exception.usePointer(exception => {
+            value._use(valuePtr => {
+                ImageMagick._api._DrawingWand_TextUnderColor(this._instance, valuePtr, exception);
+            });
+        });
+    }
+
     /** @internal */
     static _create(image: IMagickImage, settings: MagickSettings): DrawingWand {
         return new DrawingWand(image, settings);

src/index.ts

@@ -34,6 +34,7 @@ export * from './drawables/drawable-text-decoration';
 export * from './drawables/drawable-text-interline-spacing';
 export * from './drawables/drawable-text-interword-spacing';
 export * from './drawables/drawable-text-kerning';
+export * from './drawables/drawable-text-under-color';
 export * from './drawables/drawable-text';
 export * from './drawables/drawable';
 export * from './drawables/drawing-wand';

tests/drawables/drawable-text-under-color.spec.ts

@@ -0,0 +1,41 @@
+// Copyright Dirk Lemstra https://github.com/dlemstra/magick-wasm.
+// Licensed under the Apache License, Version 2.0.
+
+import { DrawableFont } from "../../src/drawables/drawable-font";
+import { DrawableFontPointSize } from "../../src/drawables/drawable-font-point-size";
+import { DrawableText } from "../../src/drawables/drawable-text";
+import { DrawableTextUnderColor } from "../../src/drawables/drawable-text-under-color";
+import { MagickColors } from "../../src/magick-colors";
+import { TestFonts } from "../test-fonts";
+import { TestImages } from "../test-images";
+
+describe("DrawableTextUnderColor", () => {
+    it("should write text without text under color to the image", () => {
+        TestImages.emptyCanvas.use((image) => {
+            image.draw([
+                new DrawableFont(TestFonts.kaushanScriptRegularTtf.name),
+                new DrawableFontPointSize(80),
+                new DrawableText(0, 100, "I"),
+            ]);
+
+            expect(image).toHavePixelWithColor(37, 50, "#ffffffff");
+            expect(image).toHavePixelWithColor(38, 50, "#ffffffff");
+            expect(image).toHavePixelWithColor(39, 50, "#ffffffff");
+        });
+    });
+
+    it("should write text with text under color to the image", () => {
+        TestImages.emptyCanvas.use((image) => {
+            image.draw([
+                new DrawableFont(TestFonts.kaushanScriptRegularTtf.name),
+                new DrawableFontPointSize(80),
+                new DrawableTextUnderColor(MagickColors.Pink),
+                new DrawableText(0, 100, "I"),
+            ]);
+
+            expect(image).toHavePixelWithColor(37, 50, "#ffc0cbff");
+            expect(image).toHavePixelWithColor(38, 50, "#fffcfdff");
+            expect(image).toHavePixelWithColor(39, 50, "#ffffffff");
+        });
+    });
+});