diff --git a/constants.asm b/constants.asm
index 96509d3..fbbb01e 100644
--- a/constants.asm
+++ b/constants.asm
@@ -191,10 +191,10 @@ sintable
     .by 255
     .by 255 ;anti self destruction byte
 
-linetableL
-    :screenheight+1 .by <(display+screenBytes*#)
-linetableH
-    :screenheight+1 .by >(display+screenBytes*#)
+;linetableL
+;    :screenheight+1 .by <(display+screenBytes*#)
+;linetableH
+;    :screenheight+1 .by >(display+screenBytes*#)
 ;----------------------------
 bittable
     .by $80,$40,$20,$10,$08,$04,$02,$01
diff --git a/definitions.asm b/definitions.asm
index 4d0d952..91094b4 100644
--- a/definitions.asm
+++ b/definitions.asm
@@ -1,14 +1,20 @@
 ;   @com.wudsn.ide.asm.mainsourcefile=scorch.asm
 
-;----------------------------------------------
-; Player/missile memory
-    
-PMGraph =  $0800
-display = $1010 ;screen takes $2K due to clearing routine
-
 screenheight = 200
 screenBytes = 40
 screenwidth = screenBytes*8 ; Max screenwidth = 512!!!
+
+;----------------------------------------------
+; Player/missile memory
+PMGraph =  $0800  ; real PM start = $0b00
+
+
+; Generated tables
+linetableL = $0b00 - screenHeight*2
+linetableH = $0b00 - screenHeight
+
+display = $1010 ;screen takes $2K due to clearing routine
+
 margin = 40 ;mountain drawing Y variable margin
 MaxPlayers = 6
 maxOptions = 8  ;number of all options
diff --git a/scorch.asm b/scorch.asm
index f0b6164..6c37d95 100644
--- a/scorch.asm
+++ b/scorch.asm
@@ -177,6 +177,22 @@ FirstSTART
 	dey
 	bpl @-
 
+
+    ; generate linetables
+    mwa #display temp
+    mwa #linetableL temp2
+    mwa #linetableH modify
+    ldy #0
+@     lda temp
+      sta (temp2),y
+      lda temp+1
+      sta (modify),y
+      adw temp #40
+      iny
+      cpy #screenheight
+    bne @-
+
+
     ; RMT INIT
     lda #$f0                    ;initial value
     sta RMTSFXVOLUME            ;sfx note volume * 16 (0,16,32,...,240)
@@ -1626,6 +1642,19 @@ noingame
 	mva #0 RMT_blocked
 	rts
 .endp
+;;--------------------------------------------------
+;.proc Randomizer
+;;--------------------------------------------------
+;    ;usage: randomize floor ceiling
+;    ;returns (in A) a random .byte between "floor" and "ceiling"
+;?rand
+;      lda random
+;      cmp #:1 ;floor
+;      bcc ?rand
+;      cmp #:2+1 ;ceiling
+;      bcs ?rand
+;      rts
+;.endp
 ;----------------------------------------------
     icl 'weapons.asm'
 ;----------------------------------------------
diff --git a/scorch.xex b/scorch.xex
index aa0df24..f7e137d 100644
Binary files a/scorch.xex and b/scorch.xex differ