Add Sprite Creator preview export

Author: ToolboxAid

assets/theme-v2/css/gamefoundrystudio.css

@@ -1239,6 +1239,24 @@ body.tool-focus-mode .tool-column:last-of-type {
   box-shadow: 0 1px 4px var(--swatch-shadow-color)
 }
 
+.sprite-preview-shell {
+  display: flex;
+  justify-content: center;
+  padding: 12px;
+  border: 1px solid var(--line);
+  border-radius: var(--radius-md);
+  background: var(--panel-soft)
+}
+
+.sprite-preview-canvas {
+  width: min(100%, 160px);
+  height: auto;
+  aspect-ratio: 1;
+  border: 1px solid var(--line);
+  background: var(--card-background);
+  image-rendering: pixelated
+}
+
 @media(max-width:980px) {
 
   .grid.cols-4,

assets/toolbox/sprites/js/index.js

@@ -2,6 +2,13 @@ const DEFAULT_GRID_SIZE = 16;
 const SUPPORTED_GRID_SIZES = Object.freeze([16, 32]);
 const DRAWING_TOOLS = Object.freeze(["pencil", "eraser", "fill"]);
 const EDITOR_COLOR_KEYS = Object.freeze(["ink", "orange", "gold", "green", "blue"]);
+const EDITOR_COLOR_CSS_VARIABLES = Object.freeze({
+  blue: "--electric-blue",
+  gold: "--forge-gold",
+  green: "--green",
+  ink: "--text",
+  orange: "--molten-orange",
+});
 
 const editorState = {
   activeTool: "pencil",
@@ -51,6 +58,7 @@ function updateDraftStatus() {
   if (status) {
     status.textContent = draftStatusText();
   }
+  renderPreview();
 }
 
 function updatePaletteStatus() {
@@ -114,6 +122,64 @@ function fillGrid() {
   updateDraftStatus();
 }
 
+function editorColorValue(colorKey) {
+  const variableName = EDITOR_COLOR_CSS_VARIABLES[normalizeColorKey(colorKey)];
+  const value = getComputedStyle(document.documentElement).getPropertyValue(variableName).trim();
+  return value || "#111111";
+}
+
+function renderPreview() {
+  const canvas = document.querySelector("[data-sprites-preview-canvas]");
+  if (!canvas) {
+    return;
+  }
+  const context = canvas.getContext("2d");
+  if (!context) {
+    return;
+  }
+  const size = editorState.gridSize;
+  const cellSize = canvas.width / size;
+  context.clearRect(0, 0, canvas.width, canvas.height);
+  for (const [key, colorKey] of editorState.paintedPixels.entries()) {
+    const [rowText, columnText] = key.split(":");
+    const row = Number(rowText);
+    const column = Number(columnText);
+    if (!Number.isFinite(row) || !Number.isFinite(column)) {
+      continue;
+    }
+    context.fillStyle = editorColorValue(colorKey);
+    context.fillRect((column - 1) * cellSize, (row - 1) * cellSize, cellSize, cellSize);
+  }
+}
+
+function exportPreviewPng() {
+  const canvas = document.querySelector("[data-sprites-preview-canvas]");
+  const status = document.querySelector("[data-sprites-export-status]");
+  if (!canvas) {
+    return;
+  }
+  canvas.toBlob((blob) => {
+    if (!blob) {
+      if (status) {
+        status.textContent = "PNG export is unavailable in this browser session.";
+      }
+      return;
+    }
+    const objectUrl = URL.createObjectURL(blob);
+    const link = document.createElement("a");
+    link.href = objectUrl;
+    link.download = "sprite-creator-draft.png";
+    link.rel = "noopener";
+    document.body.append(link);
+    link.click();
+    link.remove();
+    URL.revokeObjectURL(objectUrl);
+    if (status) {
+      status.textContent = "PNG downloaded from unsaved editor draft.";
+    }
+  }, "image/png");
+}
+
 function setGridSize(size) {
   const grid = document.querySelector("[data-sprites-pixel-grid]");
   const status = document.querySelector("[data-sprites-grid-status]");
@@ -186,9 +252,18 @@ function wirePaletteButtons() {
   });
 }
 
+function wireExportButton() {
+  const button = document.querySelector("[data-sprites-export-png]");
+  if (button) {
+    button.addEventListener("click", exportPreviewPng);
+  }
+}
+
 wireGridControls();
 wireDrawingTools();
 wirePaletteButtons();
+wireExportButton();
 setGridSize(DEFAULT_GRID_SIZE);
 setActiveTool(editorState.activeTool);
 setActiveColor(editorState.activeColor);
+renderPreview();

dev/tests/playwright/tools/SpritesToolShell.spec.mjs

@@ -260,6 +260,18 @@ test("Sprite Creator shell loads with visible tool, canvas, details, and status
     await expect(page.locator("[data-sprites-pixel-grid] .is-painted")).toHaveCount(1024);
     await expect(page.locator("[data-sprites-pixel-grid] .sprite-canvas-cell--blue")).toHaveCount(1024);
     await expect(page.locator("[data-sprites-draft-status]")).toContainText("1024 draft pixels painted");
+    await expect(page.locator("[data-sprites-preview-canvas]")).toBeVisible();
+    const previewHasPaint = await page.locator("[data-sprites-preview-canvas]").evaluate((canvas) => {
+      const context = canvas.getContext("2d");
+      const pixel = context.getImageData(1, 1, 1, 1).data;
+      return pixel[3] > 0;
+    });
+    expect(previewHasPaint).toBe(true);
+    const downloadPromise = page.waitForEvent("download");
+    await page.getByRole("button", { name: "Download PNG" }).click();
+    const download = await downloadPromise;
+    expect(download.suggestedFilename()).toBe("sprite-creator-draft.png");
+    await expect(page.locator("[data-sprites-export-status]")).toContainText("PNG downloaded");
     await expect(page.locator("[data-sprites-shell-status]")).toContainText("Editor ready");
     await expect(page.locator("main")).toContainText("Palette/Colors remains the reusable color source");
     await expect(page.locator("main")).not.toContainText(/Not implemented yet|future rebuild work|Static wireframe only|Plan sprite creation/i);

docs_build/dev/reports/PR_26179_CHARLIE_027-sprites-preview-export.md

@@ -0,0 +1,62 @@
+# PR_26179_CHARLIE_027-sprites-preview-export
+
+Team: CHARLIE
+Workflow: stacked feature workflow
+Base branch: PR_26179_CHARLIE_026-sprites-palette-panel
+Canonical ZIP path: dev/workspace/zip/PR_26179_CHARLIE_027-sprites-preview-export_delta.zip
+
+## Summary
+
+Added live preview and PNG download/export for the unsaved Sprite Creator editor draft. Export uses canvas `toBlob` and browser download behavior. This PR does not save to library, publish, write browser storage, or add API/DB/schema changes.
+
+## Branch Validation
+
+PASS
+
+- Current branch: PR_26179_CHARLIE_027-sprites-preview-export
+- Based on: PR_26179_CHARLIE_026-sprites-palette-panel
+- No start_of_day files changed
+- No DB/API/schema files changed
+- No stale PR #219-#228 code copied
+
+## Requirement Checklist
+
+| Requirement | Status | Notes |
+| --- | --- | --- |
+| Add live preview | PASS | Preview canvas reflects unsaved draft pixels. |
+| Add PNG export/download | PASS | Download button exports `sprite-creator-draft.png`. |
+| No save-to-library | PASS | No saved sprite library or product persistence added. |
+| No publishing | PASS | Export is local download only. |
+| Avoid persisted data URLs | PASS | Uses `canvas.toBlob`; no `imageDataUrl` or `toDataURL`. |
+| No DB/API/schema changes | PASS | Only UI/JS/CSS/test/report files changed. |
+
+## Validation Lane Report
+
+Commands:
+
+```text
+node --check assets/toolbox/sprites/js/index.js
+node --check dev/tests/playwright/tools/SpritesToolShell.spec.mjs
+git diff --check -- toolbox/sprites/index.html assets/toolbox/sprites/js/index.js assets/theme-v2/css/gamefoundrystudio.css dev/tests/playwright/tools/SpritesToolShell.spec.mjs
+rg --pcre2 -n -i "localStorage|sessionStorage|indexedDB|imageDataUrl|toDataURL|<style|style=|<script(?![^>]+src=)|on(click|change|submit|input|load|error)=|local-mem|fake-login|MEM DB" toolbox/sprites/index.html assets/toolbox/sprites/js/index.js dev/tests/playwright/tools/SpritesToolShell.spec.mjs
+npx playwright test dev/tests/playwright/tools/SpritesToolShell.spec.mjs --workers=1 --reporter=list --output=<temp>
+```
+
+Results:
+
+- Node syntax checks: PASS
+- `git diff --check`: PASS
+- Guard scan: PASS, no matches
+- Targeted Playwright: PASS, 1 test passed
+
+## Manual Validation Notes
+
+1. Open `/toolbox/sprites/index.html` from the stacked branch.
+2. Draw or fill pixels.
+3. Confirm the preview canvas shows the draft.
+4. Click Download PNG and confirm a `sprite-creator-draft.png` download starts.
+5. Confirm no save-to-library or publishing controls are present.
+
+## ZIP Path
+
+`dev/workspace/zip/PR_26179_CHARLIE_027-sprites-preview-export_delta.zip`

docs_build/dev/reports/codex_changed_files.txt

@@ -2,6 +2,6 @@
 assets/toolbox/sprites/js/index.js
 assets/theme-v2/css/gamefoundrystudio.css
 dev/tests/playwright/tools/SpritesToolShell.spec.mjs
-docs_build/dev/reports/PR_26179_CHARLIE_026-sprites-palette-panel.md
+docs_build/dev/reports/PR_26179_CHARLIE_027-sprites-preview-export.md
 docs_build/dev/reports/codex_changed_files.txt
 docs_build/dev/reports/codex_review.diff