Fix bug in Wimp_WhichIcon

When matching an icon on the iconbar the window is initially matched correctly, but the "is this the right task" filter step was trying to compare the handle with -1. The result was that you would get the first match for any iconbar icon rather than a match for *your* iconbar icon.
Unrelated: Tiling.s/Iconbar.s add a couple of comments and use symbols instead of magic numbers.
Tested with a quality 3 line BASIC program, no longer returns icon #0 all the time.

Version 5.23. Tagged as 'Wimp-5_23'

VersionASM

@@ -11,13 +11,13 @@
                         GBLS    Module_HelpVersion
                         GBLS    Module_ComponentName
                         GBLS    Module_ComponentPath
-Module_MajorVersion     SETS    "5.22"
-Module_Version          SETA    522
+Module_MajorVersion     SETS    "5.23"
+Module_Version          SETA    523
 Module_MinorVersion     SETS    ""
-Module_Date             SETS    "10 Apr 2013"
-Module_ApplicationDate  SETS    "10-Apr-13"
+Module_Date             SETS    "13 Apr 2013"
+Module_ApplicationDate  SETS    "13-Apr-13"
 Module_ComponentName    SETS    "Wimp"
 Module_ComponentPath    SETS    "castle/RiscOS/Sources/Desktop/Wimp"
-Module_FullVersion      SETS    "5.22"
-Module_HelpVersion      SETS    "5.22 (10 Apr 2013)"
+Module_FullVersion      SETS    "5.23"
+Module_HelpVersion      SETS    "5.23 (13 Apr 2013)"
                         END

VersionNum

-/* (5.22)
+/* (5.23)
  *
  * This file is automatically maintained by srccommit, do not edit manually.
  * Last processed by srccommit version: 1.1.
  *
  */
-#define Module_MajorVersion_CMHG        5.22
+#define Module_MajorVersion_CMHG        5.23
 #define Module_MinorVersion_CMHG        
-#define Module_Date_CMHG                10 Apr 2013
+#define Module_Date_CMHG                13 Apr 2013
 
-#define Module_MajorVersion             "5.22"
-#define Module_Version                  522
+#define Module_MajorVersion             "5.23"
+#define Module_Version                  523
 #define Module_MinorVersion             ""
-#define Module_Date                     "10 Apr 2013"
+#define Module_Date                     "13 Apr 2013"
 
-#define Module_ApplicationDate          "10-Apr-13"
+#define Module_ApplicationDate          "13-Apr-13"
 
 #define Module_ComponentName            "Wimp"
 #define Module_ComponentPath            "castle/RiscOS/Sources/Desktop/Wimp"
 
-#define Module_FullVersion              "5.22"
-#define Module_HelpVersion              "5.22 (10 Apr 2013)"
-#define Module_LibraryVersionInfo       "5:22"
+#define Module_FullVersion              "5.23"
+#define Module_HelpVersion              "5.23 (13 Apr 2013)"
+#define Module_LibraryVersionInfo       "5:23"

s/Iconbar

@@ -155,7 +155,7 @@ addtoR1
 ; if indirected can be turned off with validation X
         Push    R3
         LDR     R3,[R1,#4]
-        MOV     R2,#"X"
+        MOV     R2,#WimpValidation_NoAuto
         BL      findcommand
         Pull    R3
         BEQ     %FT9                    ; found X
@@ -644,7 +644,7 @@ resizeicons_loop
         BLHI    mapslotinout
 ; so that indirected data is ok. Now R1-> text
         Push    "R2,R3"
-        MOV     R2,#"X"
+        MOV     R2,#WimpValidation_NoAuto
         LDR     R3,[R5,#i_data+4]                 ; validation string
         BL      findcommand
         Pull    "R2,R3"

s/Tiling

@@ -56,8 +56,8 @@ plotspritebackground
 
         LDR     R1,[handle,#w_areaCBptr]
         CMP     R1,#2
-        BLO     %FT3
-        MOV     R0,#24
+        BLO     %FT3                            ; 0 ==> system, 1 ==> wimp, else user
+        MOV     R0,#SpriteReason_SelectSprite
         ORR     R0,R0,#256
         ADR     R2,plotsprite_tile1
         SWI     XOS_SpriteOp
@@ -101,9 +101,9 @@ plotspritebackground
         B       %FT6
 3
         LDR     R2,tiling_sprite
-        CMP     R2,#0
+        CMP     R2,#0                   ; disabled/not there
         BEQ     %FT4
-        CMP     R2,#-1
+        CMP     R2,#-1                  ; needs recache
         LDRNE   R1,baseofsprites
         BNE     %FT5
         BLEQ    findwimptilesprite

s/Wimp04

@@ -5178,7 +5178,7 @@ int_which_icon
 whiclp
         CMP     R4,R6
         BHS     endwhlp
-        CMP     R0,#nullptr             ; if iconbar,
+        CMP     R0,#nullptr2            ; if iconbar,
         BNE     %FT01                   ; check that the task owns this icon
         Push    "R1,R2,R7"
         BL      findicon                ; R2 -> iconblock