feat: upgrade city stay exploration

scripts/verify-exploration-character-asset-data.mjs

@@ -21,11 +21,14 @@ const expectedBaseMappings = {
   'unit-shu-infantry': 'exploration-shu-infantry'
 };
 const expectedNamedTextureFallbacks = {
+  'exploration-huang-quan': 'unit-shu-officer',
+  'exploration-jian-yong': 'unit-shu-officer',
+  'exploration-mi-zhu': 'unit-shu-officer',
+  'exploration-zhuge-liang': 'unit-shu-officer',
   'exploration-zhuo-recruiting-clerk': 'unit-shu-officer',
   'exploration-zhuo-villager': 'unit-shu-infantry',
   'exploration-zhuo-quartermaster': 'unit-shu-officer',
-  'exploration-zou-jing': 'unit-shu-officer',
-  'exploration-jian-yong': 'unit-shu-officer'
+  'exploration-zou-jing': 'unit-shu-officer'
 };
 const expectedSceneNpcTextureKeys = [
   {
@@ -136,17 +139,22 @@ assert.deepEqual(
 
 deployedFiles.forEach((fileName) => {
   const path = join(characterDirectory, fileName);
-  const dimensions = webpDimensions(path);
+  const inspection = inspectWebp(path);
   assert.equal(
-    dimensions.width,
+    inspection.width,
     expectedWidth,
     `${path}: expected ${expectedWidth}px width for 16 frames per direction.`
   );
   assert.equal(
-    dimensions.height,
+    inspection.height,
     expectedHeight,
     `${path}: expected ${expectedHeight}px height for four direction rows.`
   );
+  assert.equal(
+    inspection.hasAlpha,
+    true,
+    `${path}: exploration character sheets must preserve transparent backgrounds.`
+  );
 });
 
 console.log(
@@ -172,7 +180,7 @@ function readStringMap(source, mappingName) {
   return mappings;
 }
 
-function webpDimensions(path) {
+function inspectWebp(path) {
   const bytes = readFileSync(path);
   assert(
     bytes.subarray(0, 4).toString('ascii') === 'RIFF' &&
@@ -181,6 +189,8 @@ function webpDimensions(path) {
   );
 
   let offset = 12;
+  let dimensions;
+  let hasAlpha = false;
   while (offset + 8 <= bytes.length) {
     const chunkType = bytes.subarray(offset, offset + 4).toString('ascii');
     const chunkSize = bytes.readUInt32LE(offset + 4);
@@ -191,20 +201,22 @@ function webpDimensions(path) {
     );
 
     if (chunkType === 'VP8X') {
-      return {
+      dimensions = {
         width: bytes.readUIntLE(payloadOffset + 4, 3) + 1,
         height: bytes.readUIntLE(payloadOffset + 7, 3) + 1
       };
-    }
-    if (chunkType === 'VP8L') {
+      hasAlpha ||= (bytes[payloadOffset] & 0x10) !== 0;
+    } else if (chunkType === 'ALPH') {
+      hasAlpha = true;
+    } else if (chunkType === 'VP8L') {
       const bits = bytes.readUInt32LE(payloadOffset + 1);
-      return {
+      dimensions ??= {
         width: (bits & 0x3fff) + 1,
         height: ((bits >>> 14) & 0x3fff) + 1
       };
-    }
-    if (chunkType === 'VP8 ') {
-      return {
+      hasAlpha ||= (bits & 0x10000000) !== 0;
+    } else if (chunkType === 'VP8 ') {
+      dimensions ??= {
         width: bytes.readUInt16LE(payloadOffset + 6) & 0x3fff,
         height: bytes.readUInt16LE(payloadOffset + 8) & 0x3fff
       };
@@ -213,5 +225,6 @@ function webpDimensions(path) {
     offset = payloadOffset + chunkSize + (chunkSize % 2);
   }
 
-  throw new Error(`${path}: could not read WebP dimensions.`);
+  assert(dimensions, `${path}: could not read WebP dimensions.`);
+  return { ...dimensions, hasAlpha };
 }