Add support to draw images via MCP on the RLCD display

2026-06-01 12:41:14 -04:00
parent 17017ff6e1
commit 0c67ff4e20
2 changed files with 111 additions and 0 deletions
@@ -24,6 +24,74 @@ def main():
            # Parse request to ensure it's valid JSON
            req_data = json.loads(line.strip())
            
+            # Intercept draw_image tool and pre-process the image on the host PC
+            if req_data.get("method") == "tools/call" and req_data.get("params", {}).get("name") == "draw_image":
+                try:
+                    args = req_data.get("params", {}).get("arguments", {})
+                    image_base64 = args.get("image_base64")
+                    
+                    if not image_base64:
+                        raise ValueError("Missing image_base64 parameter")
+                        
+                    # Strip data URI prefix if present
+                    if image_base64.startswith("data:"):
+                        if ";base64," in image_base64:
+                            image_base64 = image_base64.split(";base64,")[1]
+                            
+                    import base64
+                    import io
+                    from PIL import Image
+                    
+                    img_bytes = base64.b64decode(image_base64)
+                    img = Image.open(io.BytesIO(img_bytes))
+                    
+                    # Convert to grayscale
+                    img = img.convert("L")
+                    
+                    # Resize to fit screen dimensions (400x300 max)
+                    max_w = int(args.get("maxWidth", 400))
+                    max_h = int(args.get("maxHeight", 300))
+                    
+                    # Prevent going over physical screen bounds
+                    max_w = min(max_w, 400)
+                    max_h = min(max_h, 300)
+                    
+                    img.thumbnail((max_w, max_h))
+                    
+                    # Convert to 1-bit monochrome (with optional Floyd-Steinberg dithering)
+                    dither = args.get("dither", True)
+                    img_1bit = img.convert("1", dither=Image.FLOYDSTEINBERG if dither else Image.NONE)
+                    
+                    # Save as binary PBM (P4 format) using PPM format writer on mode 1
+                    pbm_io = io.BytesIO()
+                    img_1bit.save(pbm_io, format="PPM")
+                    pbm_data = pbm_io.getvalue()
+                    
+                    # Encode processed PBM to base64
+                    pbm_b64 = base64.b64encode(pbm_data).decode("utf-8")
+                    
+                    # Substitute arguments for ESP32
+                    new_args = {
+                        "pbm_base64": pbm_b64,
+                        "x": args.get("x", 0),
+                        "y": args.get("y", 0)
+                    }
+                    req_data["params"]["arguments"] = new_args
+                    
+                except Exception as e:
+                    # Return error response directly to client without contacting ESP32
+                    err_resp = {
+                        "jsonrpc": "2.0",
+                        "error": {
+                            "code": -32602,
+                            "message": f"Bridge image preprocessing failed: {str(e)}"
+                        },
+                        "id": req_data.get("id")
+                    }
+                    sys.stdout.write(json.dumps(err_resp) + "\n")
+                    sys.stdout.flush()
+                    continue
+            
            # Forward the JSON-RPC request to the ESP32 board via HTTP POST
            req = urllib.request.Request(
                url,