r996 - dev/olpc/touchpad

Author: wmb
Date: 2008-11-06 09:47:40 +0100 (Thu, 06 Nov 2008)
New Revision: 996

Modified:
   dev/olpc/touchpad/touchpad.fth
Log:
OLPC trac #8940 - fixed glitches in selftest for OLPC ALPS touchpad.
The problem was that the display routine was looking at the mode
variable to determine how to display the dot, but that variable had
sometimes already been switched to the new mode, before the packet
from the old mode had been displayed.  I also changed the display
to overlay cyan and yellow in the center of the screen, with
registration to corresponding positions on the touchpad.

Modified: dev/olpc/touchpad/touchpad.fth
===================================================================
--- dev/olpc/touchpad/touchpad.fth	2008-11-06 05:46:47 UTC (rev 995)
+++ dev/olpc/touchpad/touchpad.fth	2008-11-06 08:47:40 UTC (rev 996)
@@ -90,15 +90,16 @@
 : alps-prefix  ( -- )  3 0  do  h# f2 read1 drop  loop  ;

variable mode  \ 0 - unknown  1 - GS  2 - PT  3 - mouse
+0 instance value packet-type

\ Ref: 5.2.10 (3) of Hybrid-GP2B-T-1.pdf
 : gs-only  ( -- )
-   mode @  dup 1 =  swap 3 =  or  if  exit  then
+   mode @  3 =  if  exit  then
    alps-prefix mouse1:1    \ f2 f2 f2 e6
    1 mode !
 ;
 : pt-only  ( -- )
-   mode @  dup 2 =  swap 3 =  or  if  exit  then
+   mode @  swap 3 =  if  exit  then
    alps-prefix mouse2:1    \ f2 f2 f2 e7
    2 mode !
 ;
@@ -172,7 +173,7 @@
 \ variable py    \ Pen mode y value
 variable gx    \ Glide pad x value
 variable gy    \ Glide pad y value
-variable gz    \ Glide pad z value, also used fo pen mode x
+variable gz    \ Glide pad z value, also used for pen mode x
 variable taps      \ Bitmask of tap flags
 variable switches  \ Bitmask of switch flags

@@ -233,6 +234,7 @@
 \ Ref: 5.2.9 (2) (1) of Hybrid-GP2B-T-1.pdf
 : decode-pt  ( -- )
    show-raw?  if  ." P "  then
+   2 to packet-type
    decode-common
    taps @ 0=  if  d# 10 exit-pt !  then
 ;
@@ -240,6 +242,7 @@
 \ Ref: 5.2.9 (2) (2) of Hybrid-GP2B-T-1.pdf
 : decode-gs  ( -- )
    show-raw?  if  ." G "  then
+   1 to packet-type  \ In case we get out of sync
    decode-common
    taps @  1 and  if  pt-only  then   \ Switch to pen mode
 ;
@@ -395,7 +398,7 @@
 ;

: track  ( x y z buttons -- )
-   mode @ 2 =  if  yellow  else  cyan  then  pixcolor !  ( x y z but )
+   packet-type 2 =  if  yellow  else  cyan  then  pixcolor !  ( x y z but )

dup 3 and 3 =  if  background  load-base ptr !  then
    dup  1 and  if  green  else  black  then  d# 100 button
@@ -406,7 +409,23 @@

show-pressure                          ( x y )

-   relative?  if  abs>rel  then
+   relative?  if             ( x y )
+      abs>rel                ( x' y' )
+   else                      ( x y )
+      \ Display cyan dots (GS) in the center of the screen
+      \ The offset attempts to register the GS with the PT.
+      \ The offset should be 333, but the PT is expanded,
+      \ so we have to scale the 333 to match.
+      packet-type 1 =  if    ( x y )
+         swap  d# 400 +      ( y x' )  \ GS
+         swap                ( x' y )
+      then                   ( x y )
+      \ Expand the PT (0..999) to the screen width (1200)
+      packet-type 2 =  if    ( x y )
+         swap d# 1200 d# 1000 */
+         swap d# 1200 d# 1000 */
+      then                   ( x y )
+   then                      ( x y )

dot
 ;