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Text File | 1995-11-11 | 23.7 KB | 771 lines

\ *********************************************************** \ \ PARALLAX SCROLLING DUAL PLAYFIELD WITH TEXT DEMO \ \ *********************************************************** \ \ This code demonstrates how to create a display with multiple \ dual playfield slices and variable speed parallax scrolling. \ \ This code builds upon the following Demos: \ \ Demo1_SinglePF.src \ Demo2_SinglePFCopper.src \ \ *********************************************************** \ *********************************************************** \ Re-initialise HeliOS dictionary to standard CORE vocabulary \ *********************************************************** \ This should always be used at the start of any program which \ is to be repeatedly recompiled. FORGET **CORE** \ ************************* \ Load include symbol files \ ************************* \ \ These "include files" are pre-compiled (for speed) versions of the \ Amiga includes and the Helios system includes. \ \ Uncomment the lines below for standalone compilation, but otherwise \ it is better to set these include files from the Helios Forth menus AMIGAINCLUDE HeliOS:HeliOS_AmigaInclude USERINCLUDE HeliOS:HeliOS_UserInclude \ **************************************** \ Create display imagery file name strings \ **************************************** \ These files are ordinary IFF's (and may be "PowerPacked" if required) \ \ The pictures here will be loaded into each of the display BitMaps. \ $CONSTANTL Slice1APic $Helios:Source/Data/Pic1A$ $CONSTANTL Slice1BPic $Helios:Source/Data/Pic1B$ $CONSTANTL Slice2APic $Helios:Source/Data/Pic2A$ $CONSTANTL Slice2BPic $Helios:Source/Data/Pic2B$ $CONSTANTL Slice3Pic $Helios:Source/Data/Pic3$ \ ************************************** \ Create display configuration constants \ ************************************** \ \ Collect all "display-specific" parameters here and generate "named" \ constants which make references easier than using numeric values. \ \ Collecting these together here makes it easier to adjust things at any \ time without having to search source code to replace values individually. \ 256 CONSTANT DisplayHeight \ Full PAL display 44 CONSTANT DisplayTopLine \ Display start \ The top slice is a scrolling display area with two 8-colour playfields \ \ A-slice = foreground playfield and B-slice = background playfield \ \ The B-slice has extra-wide horizontal raster size (640 pixels) to allow \ for horizontal scrolling, with an additional 320 pixels width to allow \ for horizontal smooth wrapping. \ \ The A-slice does not scroll. \ 320 CONSTANT Slice1Width \ Lores width 30 CONSTANT Slice1Height \ Top slice height 30 CONSTANT Slice1RasterHeight \ Raster=sliceheight WORDINCLUDE V_DUALPF CONSTANT Slice1Mode \ Top slice screenmode LONGINCLUDE 320 CONSTANT Slice1ARasterWidth \ Raster=screenwidth 3 CONSTANT Slice1APlanes \ A-slice bitplanes 2 Slice1APlanes 1- LSL CONSTANT Slice1AColours \ A-slice colours 640 320 + CONSTANT Slice1BRasterWidth \ Scroll plane width 3 CONSTANT Slice1BPlanes \ B-slice bitplanes \ The calculation below takes the number of bitplanes and calculates \ how many colours this represents. \ \ One bitplane gives two colours. \ \ Each additional bitplane multiplies the number of colours by two. \ \ Performing a single LSL operation on any number multipies by 2, so we \ have a quick method of multiplying by two for our colour calculation. \ \ In this case, we need "2 to the power 3", which is 2*2*2=8. \ \ e.g. 2*2*2 \ ^ ^ ^ \ Total number of planes = 3 \ \ \ So, we take the first value two \ \ e.g. 2*2*2 \ ^ \ Initial start value of 2 \ \ and we now need to multiply it by two "the_number_of_planes minus_one" \ more times. \ \ e.g. 2*2*2 \ ^ ^ \ Total planes minus one \ \ \ So, Number of colours = 2 operated on by LSL NumberOfPlanes-1 times. \ 2 Slice1BPlanes 1- LSL CONSTANT Slice1BColours \ B-slice colours \ The middle slice is a scrolling play area and has two 8 colour playfields \ \ A-slice = foreground playfield and B-slice = background playfield \ \ Both these slices have extra-wide horizontal raster size to allow for \ horizontal scrolling (1280 pixels), and an additional 320 pixels for \ horizontal smooth wrapping. \ \ These slices both also have 16 pixel extra border areas to allow \ rendering of partially off-screen BOBs, since this would normally be \ a main game play area. \ 320 CONSTANT Slice2Width \ Lores width 170 CONSTANT Slice2Height \ Middle slice height 170 32 + CONSTANT Slice2RasterHeight \ Middle bitplane height WORDINCLUDE V_DUALPF CONSTANT Slice2Mode \ Middle screenmode LONGINCLUDE 1280 320 + 32 + CONSTANT Slice2ARasterWidth \ A-slice scroll-raster 3 CONSTANT Slice2APlanes \ A-slice planes 2 Slice2APlanes 1- LSL CONSTANT Slice2AColours \ A-slice colours 640 320 + 32 + CONSTANT Slice2BRasterWidth \ B-slice scroll-raster 3 CONSTANT Slice2BPlanes \ B-slice planes 2 Slice2BPlanes 1- LSL CONSTANT Slice2BColours \ B-slice colours \ The bottom slice is an ordinary single playfield with 32 colours 640 CONSTANT Slice3Width \ Hires width 640 CONSTANT Slice3RasterWidth \ Raster=screenwidth DisplayHeight Slice1Height - Slice2Height - CONSTANT Slice3Height \ Bottom slice height 4 CONSTANT Slice3Planes \ Bottom slice planes 2 Slice3Planes 1- LSL CONSTANT Slice3Colours \ Bottom slice colours WORDINCLUDE V_HIRES CONSTANT Slice3Mode \ Bottom slice screenmode LONGINCLUDE \ *********************** \ Error handling routines \ *********************** \ This error handler allows all errors to be routed via a comprehensive \ sequential closedown routine, which is associated with the HeliOS \ system error handler word ERROR". \ \ When ERROR" senses an error, it prints an associated error message \ delimited by '"' characters, and then closes everything down using the \ routine CLOSEDOWN below which you have supplied. \ \ This simplifies errors checks to the use of a single word, ERROR", which \ displays a text message and closes eveything down. \ 0 VARIABLE (CLOSEDOWN) : ?CLOSEDOWNERROR IF CR CR TYPE CR CR ." Press <Space> to quit!" CR CR WAITSPACE (CLOSEDOWN) @EXECUTE QUIT ELSE DDROP THEN ; LATESTCFA VARIABLE ERROR1 \ ******************************** \ Create pointer storage variables \ ******************************** \ Here we create a set of "pointers", initially set to a "null" value. \ \ These "pointers" are set up as "long addresses" when various components \ of the display system are allocated and initialised. \ \ Note that initially these are all set to zero, and we clear them back \ to zero when we de-allocate the associated resource. \ \ These DPOINTERs are all initially set to "null" by using '0.'. \ \ When we allocate memory or Amiga system resources in the program at \ run-time, these pointers are updated to contain the 32-bit address \ of the newly allocated resource. \ \ Subsequently the symbolic DPOINTER name can be used in your code to \ represent the associated address. 0. DPOINTER Display1 \ Main Display structure pointer 0. DPOINTER Slice1 \ Slice 1 Slice structure pointer 0. DPOINTER Slice2 \ Slice 2 Slice structure pointer 0. DPOINTER Slice3 \ Slice 3 Slice structure pointer 0. DPOINTER Slice1_ColorMap \ Slice 1 ColourMap structure pointer 0. DPOINTER Slice2_ColorMap \ Slice 2 ColourMap structure pointer 0. DPOINTER Slice3_ColorMap \ Slice 3 ColourMap structure pointer 0. DPOINTER Slice1A_RasInfo \ Slice 1A RasInfo structure pointer 0. DPOINTER Slice1B_RasInfo \ Slice 1B RasInfo structure pointer 0. DPOINTER Slice2A_RasInfo \ Slice 2A RasInfo structure pointer 0. DPOINTER Slice2B_RasInfo \ Slice 2B RasInfo structure pointer 0. DPOINTER Slice3_RasInfo \ Slice 3 RasInfo structure pointer 0. DPOINTER Slice1A_BMap \ Slice 1A BitMap structure pointer 0. DPOINTER Slice1B_BMap \ Slice 1B BitMap structure pointer 0. DPOINTER Slice2A_BMap \ Slice 2A BitMap structure pointer 0. DPOINTER Slice2B_BMap \ Slice 2B BitMap structure pointer 0. DPOINTER Slice3_BMap \ Slice 3 BitMap structure pointer 0. DPOINTER Slice1A_SliceControl \ Slice 1A SliceControl structure pointer 0. DPOINTER Slice1B_SliceControl \ Slice 1B SliceControl structure pointer 0. DPOINTER Slice2A_SliceControl \ Slice 2A SliceControl structure pointer 0. DPOINTER Slice2B_SliceControl \ Slice 2B SliceControl structure pointer \ ************* \ Colour tables \ ************* \ Each colour entry requies 2 bytes of storage space CREATEL Slice1_ColorTable \ Create longword pointer Slice1AColours 2* ALLOT \ Allocate Slice1A colours * 2 bytes Slice1BColours 2* ALLOT \ Allocate Slice1B colours * 2 bytes CREATEL Slice2_ColorTable \ Create longword pointer Slice2AColours 2* ALLOT \ Allocate Slice2A colours * 2 bytes Slice2BColours 2* ALLOT \ Allocate Slice2B colours * 2 bytes CREATEL Slice3_ColorTable Slice3Colours 2* ALLOT \ *************************** \ Synchronised display scroll \ *************************** \ This word is plugged into the interrupt driven SliceControl handler, \ so will always execute automatically every frame with perfect timing. : MoveDisplay DDROP \ Drop SliceControl pointer 1 0 Slice1A_SliceControl SETFIELD2SCROLL \ Set 1 pixel H-scroll RAWKEY @ 79 = IF QUALIFIER @ 8 AND \ Is <Ctrl> pressed? IF 12 ELSE 4 THEN DUP 0 Slice2A_SliceControl SETFIELD1SCROLL \ Set foreground H-scroll 2/ 0 Slice2A_SliceControl SETFIELD2SCROLL \ Set background H-scroll ELSE RAWKEY @ 78 = IF QUALIFIER @ 8 AND \ Is <Ctrl> pressed? IF -12 ELSE -4 THEN DUP 0 Slice2A_SliceControl SETFIELD1SCROLL \ Set foreground H-scroll 2/ 0 Slice2A_SliceControl SETFIELD2SCROLL \ Set background H-scroll THEN THEN ; LATESTCFA VARIABLE (MoveDisplay) \ Store cfa address \ ************************************* \ Copper strip for graduated background \ ************************************* 0. DVARIABLE Copper 0. DVARIABLE CopperLength : AddCopper Display1 Copper D@ ADDCOPPERSTRIP SORTSTRIPTABLE LINKSTRIPS DDROP ; : RemCopper \ Remove custom copper list from display Display1 \ We are removing CopperList from Display1 Copper D@ DFLAG IF REMCOPPERSTRIP LINKSTRIPS DDROP ELSE DDDROP THEN ; : Create_Copper COPPERSTART Copper D! 0 [ DECIMAL ] 190 [ HEX ] FFFE COPPERWAIT DROP 0100 192 COPPERMOVE DROP 0 [ DECIMAL ] 194 [ HEX ] FFFE COPPERWAIT DROP 0200 192 COPPERMOVE DROP 0 [ DECIMAL ] 198 [ HEX ] FFFE COPPERWAIT DROP 0300 192 COPPERMOVE DROP 0 [ DECIMAL ] 202 [ HEX ] FFFE COPPERWAIT DROP 0400 192 COPPERMOVE DROP 0 [ DECIMAL ] 204 [ HEX ] FFFE COPPERWAIT DROP 0500 192 COPPERMOVE DROP 0 [ DECIMAL ] 208 [ HEX ] FFFE COPPERWAIT DROP 0600 192 COPPERMOVE DROP 0 [ DECIMAL ] 212 [ HEX ] FFFE COPPERWAIT DROP 0700 192 COPPERMOVE DROP 0 [ DECIMAL ] 216 [ HEX ] FFFE COPPERWAIT DROP 0800 192 COPPERMOVE DROP 0 [ DECIMAL ] 220 [ HEX ] FFFE COPPERWAIT DROP 0900 192 COPPERMOVE DROP 0 [ DECIMAL ] 224 [ HEX ] FFFE COPPERWAIT DROP 0A00 192 COPPERMOVE DROP 0 [ DECIMAL ] 228 [ HEX ] FFFE COPPERWAIT DROP 0B00 192 COPPERMOVE DROP 0 [ DECIMAL ] 232 [ HEX ] FFFE COPPERWAIT DROP 0C00 192 COPPERMOVE DROP 0 [ DECIMAL ] 236 [ HEX ] FFFE COPPERWAIT DROP 0D00 192 COPPERMOVE DROP 0 [ DECIMAL ] 240 [ HEX ] FFFE COPPERWAIT DROP 0E00 192 COPPERMOVE DROP 0 [ DECIMAL ] 244 [ HEX ] FFFE COPPERWAIT DROP 0F00 192 COPPERMOVE DROP [ DECIMAL ] COPPEREND CopperLength D! Copper D! ADDCOPPER ; : Free_Copper RemCopper Copper D@ FREEMEMORY ; \ *********************************** \ Create Display and Slice structures \ *********************************** \ This routine simple makes blank structures, which then need to be \ initialised in the CREATE_DISPLAY routine below. : CREATE_DSLICES DS_SIZEOF MAKESTRUCTURE Display1 MAKEPOINTER \ Main "Display" structure SL_SIZEOF MAKESTRUCTURE Slice1 MAKEPOINTER \ Top "Slice" structure SL_SIZEOF MAKESTRUCTURE Slice2 MAKEPOINTER \ Middle "Slice" structure SL_SIZEOF MAKESTRUCTURE Slice3 MAKEPOINTER \ Bottom "Slice" structure ; : FREE_DSLICES Slice3 DDUP FREEMEMORY CLEARPOINTER Slice2 DDUP FREEMEMORY CLEARPOINTER Slice1 DDUP FREEMEMORY CLEARPOINTER Display1 DDUP FREEMEMORY CLEARPOINTER ; \ ****************************** \ Create RasInfo structures etc. \ ****************************** : CREATE_RASINFO \ First allocate and initialise complete RasInfo structures. \ \ This routine automatically allocates all BitMaps etc. \ Slice1ARasterWidth Slice1RasterHeight Slice1APlanes OPENRASINFO DFLAG0= ERROR" Fail: RasInfo1A" Slice1A_RasInfo MAKEPOINTER Slice1BRasterWidth Slice1RasterHeight Slice1BPlanes OPENRASINFO DFLAG0= ERROR" Fail: RasInfo1B" Slice1B_RasInfo MAKEPOINTER Slice2ARasterWidth Slice2RasterHeight Slice2APlanes OPENRASINFO DFLAG0= ERROR" Fail: RasInfo2A" Slice2A_RasInfo MAKEPOINTER Slice2BRasterWidth Slice2RasterHeight Slice2BPlanes OPENRASINFO DFLAG0= ERROR" Fail: RasInfo2B" Slice2B_RasInfo MAKEPOINTER Slice3RasterWidth Slice3Height Slice3Planes OPENRASINFO DFLAG0= ERROR" Fail: RasInfo3" Slice3_RasInfo MAKEPOINTER \ Set invisible area "sprite margins" for middle slice RasInfo 16 Slice2A_RasInfo ri_RxOffset INDEX!L 16 Slice2A_RasInfo ri_RyOffset INDEX!L 16 Slice2B_RasInfo ri_RxOffset INDEX!L 16 Slice2B_RasInfo ri_RyOffset INDEX!L \ Link Dual Playfield RasInfo structures Slice1B_RasInfo Slice1A_RasInfo ri_Next INDEXD!L Slice2B_RasInfo Slice2A_RasInfo ri_Next INDEXD!L \ Store BitMap pointers - often useful for later reference Slice1A_RasInfo ri_BitMap INDEXD@L Slice1A_BMap MAKEPOINTER Slice1B_RasInfo ri_BitMap INDEXD@L Slice1B_BMap MAKEPOINTER Slice2A_RasInfo ri_BitMap INDEXD@L Slice2A_BMap MAKEPOINTER Slice2B_RasInfo ri_BitMap INDEXD@L Slice2B_BMap MAKEPOINTER Slice3_RasInfo ri_BitMap INDEXD@L Slice3_BMap MAKEPOINTER ; : FREE_RASINFO Slice3_RasInfo DDUP CLOSERASINFO CLEARPOINTER Slice2B_RasInfo DDUP CLOSERASINFO CLEARPOINTER Slice2A_RasInfo DDUP CLOSERASINFO CLEARPOINTER Slice1B_RasInfo DDUP CLOSERASINFO CLEARPOINTER Slice1A_RasInfo DDUP CLOSERASINFO CLEARPOINTER ; \ ************************ \ Create Slice Copperlists \ ************************ \ This function builds the main display copperlist by: \ \ 1. Initialising the individual Slice data structures \ 2. Calling MAKECOPSTRIP for each slice, to build Slice copperlists \ 3. Calling MAKEDISPLAY to build the master Display copperlist \ : CREATE_DISPLAY \ First initialise main display structures Slice1 Display1 DS_Slice INDEXD!L Slice2 Slice1 SL_Next INDEXD!L Slice1Width Slice1 SL_DWidth INDEX!L Slice1Height Slice1 SL_DHeight INDEX!L DisplayTopLine Slice1 SL_DyOffset INDEX!L Slice1A_RasInfo Slice1 SL_RasInfo INDEXD!L Slice1_ColorMap Slice1 SL_ColorMap INDEXD!L Slice1Mode Slice1 SL_Modes INDEX!L Slice3 Slice2 SL_Next INDEXD!L Slice2Width Slice2 SL_DWidth INDEX!L Slice2Height Slice2 SL_DHeight INDEX!L Slice1Height DisplayTopLine + 1+ Slice2 SL_DyOffset INDEX!L Slice2A_RasInfo Slice2 SL_RasInfo INDEXD!L Slice2_ColorMap Slice2 SL_ColorMap INDEXD!L Slice2Mode Slice2 SL_Modes INDEX!L Slice3Width Slice3 SL_DWidth INDEX!L Slice3Height Slice3 SL_DHeight INDEX!L Slice1Height Slice2Height + DisplayTopLine + 2+ Slice3 SL_DyOffset INDEX!L Slice3_RasInfo Slice3 SL_RasInfo INDEXD!L Slice3_ColorMap Slice3 SL_ColorMap INDEXD!L Slice3Mode Slice3 SL_Modes INDEX!L \ Generate copper list information for each of the display slices Slice1 MAKECOPSTRIP D0= ERROR" Fail: Slice1CopStrip" Slice2 MAKECOPSTRIP D0= ERROR" Fail: Slice2CopStrip" Slice3 MAKECOPSTRIP D0= ERROR" Fail: Slice3CopStrip" \ Make display Display1 MAKEDISPLAY D0= ERROR" Fail: Display1" ; : FREE_DISPLAY Display1 FREEDISPLAY Slice3 FREECOPSTRIP Slice2 FREECOPSTRIP Slice1 FREECOPSTRIP ; \ *************************************************** \ Create SliceControl structures for scrolling slices \ *************************************************** \ SliceControl structures are used to control any slices which perform \ mapping or scrolling functions, or which require double or triple \ playfield buffering. \ \ In this case we have two slices which scroll horizontally, each with \ automatic wrap. \ \ The front middle slice playfield in this case is double buffered to \ allow smooth BOB rendering as a game main playfield. \ \ The HeliOS SLICECONTROL functions are extremely powerful, since they \ handle all the double buffering and scrolling with automatic wrap. \ : CREATE_SLICECONTROLS \ Make two top Dual-Playfield SliceControls, each playfield with standard \ single buffered bitmap displays, as indicated by "-1" parameters Slice1 -1 -1 -1 -1 MAKEDPSLICECONTROL DFLAG0= ERROR" Fail: SliceControl1" Slice1A_SliceControl MAKEPOINTER \ Get second dual playfield SliceControl pointer Slice1A_SliceControl SliceControl_DPSControl2 INDEXD@L Slice1B_SliceControl MAKEPOINTER \ Set BPLCON2 control value [ BIN ] 100100 [ DECIMAL ] Slice1A_SliceControl SliceControl_BPLCON2 INDEX!L \ Set up rear playfield for automatic horizontal smooth wrapping 1 Slice1B_SliceControl SliceControl_HWrapFlag INDEX!L \ Make middle two Dual-Playfield SliceControls, the rear playfield with \ a standard single buffered bitmap display, configured by "-1" parameters, \ and the front one with a double buffered display, configured by the 0 \ parameters. Slice2 0 0 -1 -1 MAKEDPSLICECONTROL DFLAG0= ERROR" Fail: SliceControl2" Slice2A_SliceControl MAKEPOINTER \ Get second dual playfield slice control Slice2A_SliceControl SliceControl_DPSControl2 INDEXD@L Slice2B_SliceControl MAKEPOINTER \ Set BPLCON2 control value [ BIN ] 100100 [ DECIMAL ] Slice2A_SliceControl SliceControl_BPLCON2 INDEX!L \ Set up both playfields for automatic horizontal smooth wrapping 1 Slice2A_SliceControl SliceControl_HWrapFlag INDEX!L 1 Slice2B_SliceControl SliceControl_HWrapFlag INDEX!L \ Install display movement control word (MoveDisplay) @ Slice2A_SliceControl SliceControl_BeforeForth INDEX!L \ Install slice controls into HeliOS display control system Slice1A_SliceControl INSTALLSLICECONTROL Slice1B_SliceControl INSTALLSLICECONTROL Slice2A_SliceControl INSTALLSLICECONTROL Slice2B_SliceControl INSTALLSLICECONTROL ; : FREE_SLICECONTROLS CLEARSLICECONTROLS Slice2B_SliceControl CLOSESLICECONTROL Slice2A_SliceControl CLOSESLICECONTROL Slice1B_SliceControl CLOSESLICECONTROL Slice1A_SliceControl CLOSESLICECONTROL ; \ These routines load IFF pictures into supplied BitMaps, and correctly \ initialise the supplied ColorTables. \ \ The ColorTables are then used to create initialised ColorMap structures. \ : CREATE_IMAGERY Slice1A_BMap Slice1_ColorTable Slice1APic 10 2 DOSLIB 10 <> ERROR" Fail: Slice1APic" Slice1B_BMap Slice1_ColorTable Slice1AColours 2 M* D+ Slice1BPic 10 2 DOSLIB 10 <> ERROR" Fail: Slice1BPic" Slice2A_BMap Slice2_ColorTable Slice2APic 10 2 DOSLIB 10 <> ERROR" Fail: Slice2APic" Slice2B_BMap Slice2_ColorTable Slice2AColours 2 M* D+ Slice2BPic 10 2 DOSLIB 10 <> ERROR" Fail: Slice2BPic" Slice3_BMap Slice3_ColorTable Slice3Pic 10 2 DOSLIB 10 <> ERROR" Fail: Slice3Pic" Slice1_ColorTable Slice1AColours Slice1BColours + MAKECOLORMAP DFLAG0= ERROR" Fail: Slice1ColorMap" Slice1_ColorMap MAKEPOINTER Slice2_ColorTable Slice2AColours Slice2BColours + MAKECOLORMAP DFLAG0= ERROR" Fail: Slice2ColorMap" Slice2_ColorMap MAKEPOINTER Slice3_ColorTable Slice3Colours MAKECOLORMAP DFLAG0= ERROR" Fail: Slice3ColorMap" Slice3_ColorMap MAKEPOINTER ; : FREE_IMAGERY Slice3_ColorMap DDUP FREECOLORMAP CLEARPOINTER Slice2_ColorMap DDUP FREECOLORMAP CLEARPOINTER Slice1_ColorMap DDUP FREECOLORMAP CLEARPOINTER ; \ ********************* \ Close down everything \ ********************* : CLOSEDOWN FREE_COPPER FREE_SLICECONTROLS FREE_DISPLAY FREE_IMAGERY FREE_RASINFO FREE_DSLICES RESETERROR" ; LATESTCFA (CLOSEDOWN) ! : TestDisplay SCRCLR CR ." **********************************************************" CR 6 FPENSET ." PARALLAX SCROLLING DUAL PLAYFIELD WITH TEXT DEMO" CR 1 FPENSET ." **********************************************************" CR CR ." This code demonstrates how to create a display with multiple" CR ." dual playfield slices and variable speed parallax scrolling." CR CR ." This code builds upon the following Demos:" CR CR ." Demo1_SinglePF.src" CR ." Demo2_SinglePFCopper.src" CR CR ." **********************************************************" CR 6 FPENSET ." Press <Space> or <L-Mouse> to see Demo" CR 3 FPENSET ." Use keyboard to change scroll speed and direction." CR ." **********************************************************" CR WAITSPACE SCRCLR ERROR1 SETERROR" CREATE_DSLICES CREATE_RASINFO CREATE_IMAGERY CREATE_DISPLAY CREATE_SLICECONTROLS CREATE_COPPER HeliOS_On 1 FrameRate !L Display1 SHOWDISPLAY 1 0 Slice1A_SliceControl SETFIELD2SCROLL \ Set 1 pixel H-scroll 4 0 Slice2A_SliceControl SETFIELD1SCROLL \ Set foreground H-scroll 2 0 Slice2A_SliceControl SETFIELD2SCROLL \ Set background H-scroll WAITSPACE HeliOS_Off CLOSEDOWN ; TestDisplay