fixed zimage guidance scale bug

public/index.html

@@ -1168,13 +1168,18 @@
       negative_prompt: (qs(`#negative_prompt${prefix}`).value || '').trim(),
       width: Number(qs(`#width${prefix}`).value) || 1024,
       height: Number(qs(`#height${prefix}`).value) || 1024,
-      guidance_scale: Number(qs(`#guidance_scale${prefix}`).value) || 6,
+      guidance_scale: Number(qs(`#guidance_scale${prefix}`).value),
       num_inference_steps: Number(qs(`#num_inference_steps${prefix}`).value) || 20,
       true_cfg_scale: Number(qs(`#true_cfg_scale${prefix}`)?.value) || 4,
       image_b64s: state.imageB64s ? state.imageB64s.slice(0, 3) : [],
       seed: state.seedRandom ? null : 0,
       resolution: (qs(`#resolution${prefix}`) && qs(`#resolution${prefix}`).value) || ''
     };
+
+    // Handle guidance_scale default value properly - only use default if value is NaN (empty input)
+    if (Number.isNaN(params.guidance_scale)) {
+      params.guidance_scale = 6;
+    }
     
     // 添加 Z-Image-Turbo 特定参数（从 UI 控件读取）
     const shiftEl = qs(`#shift${prefix}`);

server.js

@@ -312,7 +312,11 @@ app.post('/api/generate', async (req, res) => {
       negative_prompt: (body.negative_prompt ?? (body.input_args ? body.input_args.negative_prompt : undefined) ?? '').toString(),
       width: clamp(parseInt(body.width ?? (body.input_args ? body.input_args.width : 1024), 10) || 1024, 128, 2048),
       height: clamp(parseInt(body.height ?? (body.input_args ? body.input_args.height : 1024), 10) || 1024, 128, 2048),
-      guidance_scale: clamp(parseFloat(body.guidance_scale ?? (body.input_args ? body.input_args.guidance_scale : 7.5)) || 7.5, 0, 20),
+      guidance_scale: clamp((() => {
+        const raw = body.guidance_scale ?? (body.input_args ? body.input_args.guidance_scale : undefined);
+        const parsed = parseFloat(raw);
+        return Number.isNaN(parsed) ? 7.5 : parsed;
+      })(), 0, 20),
       num_inference_steps: clamp(parseInt(body.num_inference_steps ?? (body.input_args ? body.input_args.num_inference_steps : 25), 10) || 25, 1, 100),
       // Seed: support top-level or input_args.seed; if missing/null -> null (omit from payload)
       seed: (() => {
@@ -495,7 +499,14 @@ app.post('/api/generate', async (req, res) => {
 
     // Z-Image-Turbo minimal payload (top-level prompt only, as shown in curl example)
     const variantZImageMinimal = isZImageTurbo ? {
-      prompt: flat.prompt
+      prompt: flat.prompt,
+        height: flat.height,
+        width: flat.width,
+        num_inference_steps: flat.num_inference_steps,
+        guidance_scale: flat.guidance_scale,
+        shift: (inputExtras && inputExtras.shift !== undefined) ? Number(inputExtras.shift) : 3.0,
+        max_sequence_length: (inputExtras && inputExtras.max_sequence_length !== undefined) ? Number(inputExtras.max_sequence_length) : 512,
+        ...(flat.seed !== null ? { seed: flat.seed } : {})
     } : null;
 
     // Minimal payload (some models reject extended fields). Include size/steps/seed for hunyuan-image-3 compatibility
@@ -622,26 +633,13 @@ app.post('/api/generate', async (req, res) => {
       
       if (isZImageTurbo) {
         // Z-Image-Turbo: try minimal payload first (as shown in curl example)
-        if (variantZImageMinimal) {
-          try {
-            result = await tryCall(variantZImageMinimal, 'z-image-turbo-minimal', generateUrl);
-          } catch (e0) {}
-        }
-        // If minimal fails, try full nested payload
-        if (!result && variantZImageNested) {
-          try {
-            result = await tryCall(variantZImageNested, 'z-image-turbo-nested', generateUrl);
-          } catch (e1) {}
-        }
+        try {
+          result = await tryCall(variantZImageMinimal, 'z-image-turbo-minimal', generateUrl);
+        } catch (e0) {}
       } else if (isHunyuan) {
         try {
-          result = await tryCall(variantCMinimal, 'nested-minimal', generateUrl);
+          result = await tryCall(variantFlatMinimal, 'flat-minimal', generateUrl);
         } catch (e0) {}
-        if (!result) {
-          try {
-            result = await tryCall(variantFlatMinimal, 'flat-minimal', generateUrl);
-          } catch (e1) {}
-        }
       } else {
         try {
           result = await tryCall(variantFlatMinimal, 'flat-minimal', generateUrl);