diff --git a/compiler/res/prog8lib/cx16/gfx_lores.p8 b/compiler/res/prog8lib/cx16/gfx_lores.p8
index f4c867e2e..40380545a 100644
--- a/compiler/res/prog8lib/cx16/gfx_lores.p8
+++ b/compiler/res/prog8lib/cx16/gfx_lores.p8
@@ -22,6 +22,7 @@ gfx_lores {
         cx16.VERA_L1_MAPBASE = 0
         cx16.VERA_L1_TILEBASE = 0
         clear_screen(0)
+        drawmode_eor(false)
     }
 
     sub text_mode() {
@@ -31,6 +32,13 @@ gfx_lores {
         cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11111000) | cx16.r15L
     }
 
+    sub drawmode_eor(bool enabled) {
+        ; with EOR drawing mode you can have non destructive drawing (2*EOR=restore original)
+        eor_mode = enabled
+    }
+
+    bool eor_mode
+
     sub clear_screen(ubyte color) {
         if verafx.available() {
             ; use verafx cache writes to quicly clear the screen
@@ -151,27 +159,50 @@ gfx_lores {
     sub horizontal_line(uword xx, ubyte yy, uword length, ubyte color) {
         if length==0
             return
-        plot(xx, yy, color)  ; set starting position by reusing plot routine
+        position(xx, yy)
         ; set vera auto-increment to 1 pixel
         cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | (1<<4)
-
-        %asm {{
-            lda  p8v_color
-            ldx  p8v_length+1
-            beq  +
-            ldy  #0
--           sta  cx16.VERA_DATA0
-            iny
-            bne  -
-            dex
-            bne  -
-+           ldy  p8v_length     ; remaining
-            beq  +
--           sta  cx16.VERA_DATA0
-            dey
-            bne  -
+        if eor_mode {
+            cx16.vaddr_clone(0)      ; also setup port 1, for reading
+            %asm {{
+                ldx  p8v_length+1
+                beq  +
+                ldy  #0
+-               lda  p8v_color
+                eor  cx16.VERA_DATA1
+                sta  cx16.VERA_DATA0
+                iny
+                bne  -
+                dex
+                bne  -
++               ldy  p8v_length     ; remaining
+                beq  +
+-               lda  p8v_color
+                eor  cx16.VERA_DATA1
+                sta  cx16.VERA_DATA0
+                dey
+                bne  -
 +
-        }}
+            }}
+        } else {
+            %asm {{
+                lda  p8v_color
+                ldx  p8v_length+1
+                beq  +
+                ldy  #0
+-               sta  cx16.VERA_DATA0
+                iny
+                bne  -
+                dex
+                bne  -
++               ldy  p8v_length     ; remaining
+                beq  +
+-               sta  cx16.VERA_DATA0
+                dey
+                bne  -
++
+            }}
+        }
     }
 
     sub safe_horizontal_line(uword xx, ubyte yy, uword length, ubyte color) {
@@ -195,16 +226,30 @@ gfx_lores {
     sub vertical_line(uword xx, ubyte yy, ubyte lheight, ubyte color) {
         if lheight==0
             return
-        plot(xx, yy, color)  ; set starting position by reusing plot routine
+        position(xx, yy)
         ; set vera auto-increment to 320 pixel increment (=next line)
         cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | (14<<4)
-        %asm {{
-            ldy  p8v_lheight
-            lda  p8v_color
--           sta  cx16.VERA_DATA0
-            dey
-            bne  -
-        }}
+        if eor_mode {
+            cx16.vaddr_clone(0)      ; also setup port 1, for reading
+            %asm {{
+                ldy  p8v_lheight
+                beq  +
+-               lda  p8v_color
+                eor  cx16.VERA_DATA1
+                sta  cx16.VERA_DATA0
+                dey
+                bne  -
++
+            }}
+        } else {
+            %asm {{
+                ldy  p8v_lheight
+                lda  p8v_color
+-               sta  cx16.VERA_DATA0
+                dey
+                bne  -
+            }}
+        }
     }
 
     sub safe_vertical_line(uword xx, ubyte yy, ubyte lheight, ubyte color) {
@@ -339,9 +384,16 @@ gfx_lores {
                 lda  #0
                 adc  times320_hi,y
                 sta  cx16.VERA_ADDR_H
+
+                lda  p8v_eor_mode
+                bne  +
                 lda  p8v_color
                 sta  cx16.VERA_DATA0
                 rts
++               lda  p8v_color
+                eor  cx16.VERA_DATA0
+                sta  cx16.VERA_DATA0
+                rts
             }}
         }
     }
@@ -544,9 +596,16 @@ gfx_lores {
             lda  #0
             adc  times320_hi,y
             sta  cx16.VERA_ADDR_H
+
+            lda  p8v_eor_mode
+            bne  +
             lda  cx16.r0L
             sta  cx16.VERA_DATA0
             rts
++           lda  cx16.r0L
+            eor  cx16.VERA_DATA0
+            sta  cx16.VERA_DATA0
+            rts
         }}
     }
 
diff --git a/compiler/res/prog8lib/cx16/syslib.p8 b/compiler/res/prog8lib/cx16/syslib.p8
index 7a1173ac1..c021e1fd7 100644
--- a/compiler/res/prog8lib/cx16/syslib.p8
+++ b/compiler/res/prog8lib/cx16/syslib.p8
@@ -737,8 +737,7 @@ asmsub vaddr(ubyte bank @A, uword address @R0, ubyte addrsel @R1, byte autoIncrO
         ; -- setup the VERA's data address register 0 or 1
         ;    with optional auto increment or decrement of 1.
         ;    Note that the vaddr_autoincr() and vaddr_autodecr() routines allow to set all possible strides, not just 1.
-        ;    Note also that the actually selected Vera port is reset to 0 on exit, even if you set port #1's address!
-        ;    (you'll have to set ADDRSEL to 1 manually again to use that port)
+        ;    Note also that Vera's addrset is reset to 0 on exit, even if you set port #1's address.
         %asm {{
             pha
             lda  cx16.r1
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index 5d1978cbb..e01eb4ac5 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -1,8 +1,6 @@
 TODO
 ====
 
-Add a eor mode to gfx_lores / gfx_hires.  Once that's done in gfx_lores, convert Paint to use this module
-
 Improve register load order in subroutine call args assignments:
 in certain situations, the "wrong" order of evaluation of function call arguments is done which results
 in overwriting registers that already got their value, which requires a lot of stack juggling (especially on plain 6502 cpu!)