Emoji Drawing Pad with Smart Eraser

Web-App Overview

This is the definitive version of the Emoji Drawing Pad, an interactive digital canvas. It features an expanded emoji palette and introduces a major upgrade: a Smart Eraser. Instead of crudely wiping away pixels, the eraser intelligently targets and removes individual emojis, offering precise control over your creations. All previous features like dynamic audio, undo, and a non-destructive demo mode are fully supported.

How to Use

• Select an Emoji: Click an emoji from the palette to select your drawing tool.
• Draw: Press and drag on the canvas to draw.
• Smart Eraser (🧼): Click the soap icon to activate the Smart Eraser. Now, when you press and drag over the canvas, it will precisely remove only the emojis your cursor touches.
• Undo (↩️): Click to undo your last action, whether it was drawing or erasing.
• Clear Canvas (🗑️): Wipes the entire canvas clean.
• Toggle Sound (🔊/🔇): Turns the audio feedback on or off.

Technical Details

• Object-Oriented Canvas Management: This version moves beyond treating the canvas as a simple pixel map. It now maintains a JavaScript array, drawnEmojis, which acts as a "scene graph." Each object in the array stores an emoji's character, its (x, y) coordinates, and its sound profile.
• Smart Eraser Logic: When the eraser is active, a "hit detection" algorithm runs on pointer events. It checks the cursor's coordinates against the bounding box of each emoji object stored in the drawnEmojis array. If a match is found, that object is removed from the array, and the entire canvas is re-rendered from the updated array. This enables precise, object-level erasing.
• State-Based Undo System: The undo functionality has been re-engineered to work with the new object model. Instead of saving raw pixel data (getImageData), `saveState()` now saves a full copy of the drawnEmojis array. This is far more memory-efficient and robust. Undoing an action simply restores the array to its previous state and triggers a full canvas redraw.
• Optimized Rendering: A central redrawAll() function is now responsible for rendering the canvas. It clears the canvas and iterates through the `drawnEmojis` array, drawing each one. This function is called after any action that changes the scene globally, such as erasing, undoing, clearing, or resizing the window.
• Expanded Data Structure: The main `EMOJI_DATA` object now serves as a master list for populating the palette, while the separate `drawnEmojis` array stores instances of these emojis as they are placed on the canvas.