From 6a4b62579df795903052f8ce3a5fa680afd02d9f Mon Sep 17 00:00:00 2001
From: Paul Klinger <klinger.paul@gmail.com>
Date: Wed, 13 Feb 2019 01:21:19 +0100
Subject: [PATCH] truncate display_block area if too large

---
 lcd.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lcd.c b/lcd.c
index 2c5460a..6c91851 100644
--- a/lcd.c
+++ b/lcd.c
@@ -465,9 +465,9 @@ uint8_t lcd_check_buffer(uint8_t x, uint8_t y) {
     return displayBuffer[(y / (DISPLAY_HEIGHT/8))][x] & (1 << (y % (DISPLAY_HEIGHT/8)));
 }
 void lcd_display_block(uint8_t x, uint8_t line, uint8_t width) {
-    if (line > (DISPLAY_HEIGHT/8-1)) return;
-    if (x + width > DISPLAY_WIDTH - 1) {
-        width = DISPLAY_WIDTH - x - 1;
+    if (line > (DISPLAY_HEIGHT/8-1) || x > DISPLAY_WIDTH - 1){return;}
+    if (x + width > DISPLAY_WIDTH) { // no -1 here, x alone is width 1
+        width = DISPLAY_WIDTH - x;
     }
     lcd_goto_xpix_y(x,line);
     lcd_data(&displayBuffer[line][x], width);