use partial draw

src/dreader_hal/display/it8951.py

@@ -12,6 +12,7 @@ Hardware: IT8951 controller (used in Waveshare 6" e-Paper HAT and similar)
 """
 
 import asyncio
+import logging
 import sys
 import os
 from typing import Optional
@@ -25,6 +26,8 @@ from IT8951.constants import DisplayModes
 
 from ..types import RefreshMode
 
+logger = logging.getLogger(__name__)
+
 
 class IT8951DisplayDriver:
     """
@@ -93,6 +96,7 @@ class IT8951DisplayDriver:
         """Blocking initialization of display (runs in thread pool)."""
         if self.virtual:
             # Virtual display for testing
+            logger.info(f"Initializing IT8951 virtual display: {self.width}x{self.height}")
             self.display = VirtualEPDDisplay(
                 dims=(self.width, self.height),
                 rotate=self.rotate,
@@ -100,6 +104,7 @@ class IT8951DisplayDriver:
             )
         else:
             # Real e-ink display
+            logger.info(f"Initializing IT8951 e-ink display: {self.width}x{self.height}, VCOM={self.vcom}V")
             self.display = AutoEPDDisplay(
                 vcom=self.vcom,
                 bus=self.bus,
@@ -110,7 +115,9 @@ class IT8951DisplayDriver:
             )
 
         # Clear screen
+        logger.info("Clearing IT8951 display to white")
         self.display.clear()
+        logger.info("IT8951 display initialized successfully")
 
     async def cleanup(self) -> None:
         """
@@ -162,12 +169,15 @@ class IT8951DisplayDriver:
 
         # Determine refresh mode
         display_mode = self._determine_refresh_mode(mode)
+        mode_name = self._get_mode_name(display_mode)
+
+        logger.info(f"[IT8951] Displaying image {image.size} {image.mode} | Refresh #{self._refresh_count + 1} | Mode: {mode_name}")
 
         # Prepare image for e-ink
         prepared_image = self._prepare_image(image)
 
-        # Update frame buffer
-        self.display.frame_buf = prepared_image
+        # Update frame buffer using paste (more reliable than direct assignment)
+        self.display.frame_buf.paste(prepared_image, (0, 0))
 
         # Increment refresh counter
         self._refresh_count += 1
@@ -180,6 +190,8 @@ class IT8951DisplayDriver:
             display_mode
         )
 
+        logger.info(f"[IT8951] Display update completed (refresh #{self._refresh_count})")
+
         # Automatically put display to sleep after update to save power
         # E-ink displays only need power during refresh, not for static display
         if self.auto_sleep:
@@ -279,6 +291,17 @@ class IT8951DisplayDriver:
             # Default to DU (fast)
             return DisplayModes.DU
 
+    def _get_mode_name(self, display_mode: int) -> str:
+        """Get human-readable name for display mode."""
+        if display_mode == DisplayModes.INIT:
+            return "INIT (full refresh)"
+        elif display_mode == DisplayModes.DU:
+            return "DU (fast)"
+        elif display_mode == DisplayModes.GC16:
+            return "GC16 (quality)"
+        else:
+            return f"Mode {display_mode}"
+
     def _update_display(self, display_mode: int) -> None:
         """
         Update the physical display (blocking).
@@ -293,7 +316,13 @@ class IT8951DisplayDriver:
         if hasattr(self.display, 'epd') and self.auto_sleep:
             self.display.epd.run()
 
-        # Use partial update for efficiency
+        # Use full refresh for INIT mode (clears ghosting) or first few refreshes
+        # Use partial refresh for fast updates
+        if display_mode == DisplayModes.INIT or self._refresh_count <= 2:
+            # Full refresh - more reliable for initial displays
+            self.display.draw_full(display_mode)
+        else:
+            # Partial update for efficiency
             # IT8951 library tracks what changed and only updates that region
             self.display.draw_partial(display_mode)
 

src/dreader_hal/touch/ft5xx6.py

@@ -76,6 +76,7 @@ class FT5xx6TouchDriver:
         self._initialized = False
         self._last_num_touches = 0
         self._tracking_touch = False
+        self._last_touch_pos = (0, 0)  # Track last known touch position for drag_end
 
     async def initialize(self) -> None:
         """
@@ -206,6 +207,7 @@ class FT5xx6TouchDriver:
         # Handle single-touch gestures with our gesture detector
         if num_touches == 1:
             x, y = record.t1x, record.t1y
+            self._last_touch_pos = (x, y)  # Track position for drag_end
 
             # Touch down
             if self._last_num_touches == 0:
@@ -233,10 +235,10 @@ class FT5xx6TouchDriver:
         elif num_touches == 0 and self._last_num_touches > 0:
             # Get last known position
             if self._last_num_touches == 1:
-                # Single finger up
+                # Single finger up - use last tracked position
                 gesture = self.gesture_detector.on_touch_up(
-                    self.gesture_detector.current_pos[0] if self.gesture_detector.current_pos else 0,
-                    self.gesture_detector.current_pos[1] if self.gesture_detector.current_pos else 0,
+                    self._last_touch_pos[0],
+                    self._last_touch_pos[1],
                     finger=0
                 )
                 self._tracking_touch = False