Moving a larger than screen size bmp to a central point.

[Tasp]

It's me again, sorry!

This is a follow on from my previous question. Which is here link.

So you can create a map using the linked code, whereby you select a pre drawn background image and then place objects (sprites) as an overlay. Each of the objects are assigned a "zone" number.

This program is supposed to load the background map, load the objects, from a text file into an array, find the zone and position X and Y, then move the background image to make the found object centralised. Simple huh!

Well no, I know how to grab, window height and width, image size and location of object.

However I'm stuck on the equation I need to make. Nothing I seem to think of is correct. It's like I have 3 values that I don't need.

My theory is, if the object is past the center, remove the amount that its past it by, if its before then add the difference to move it to the center.

The code may seem messy again but I think I'm caught in the loop of trying to fix different sections again.



'The Zone is the object searched for when looking through the txt file of sprite positions
Zone = 1001 : ChipNumber$ = "000003a"

'TO DO
'ERROR CHECK TO SEE IF MAP DATA FILE EXISTS OTHERWISE IT'll CRASH

[MapForAlarm]
   'nomainwin

   mapID$ = ChipNumber$

   'Define file paths
   iconimg$ = DefaultDir$ + "\Images\Icons\"
   maskimg$ = DefaultDir$ + "\Images\Masked\"
   mappath$ = DefaultDir$ + "\Maps\Data\"
   Mapfile$="Maps\" + mapID$ + ".bmp"

   'load the map image and get its size
   open Mapfile$ for input as #bmp
   'the bmpfileheader
   bmp$ = Input$(#bmp,lof(#bmp))
   bmpw=value(mid$(bmp$,19,4))'width
   bmph=value(mid$(bmp$,23,4))'height
   close #bmp

   'now find out how much space the
   'window style takes for frame and title
   WindowWidth=200
   WindowHeight=200
   open "Measuring" for graphics_nf_nsb as #1
   #1, "home ; down ; posxy x y"
   ThemeWidth=WindowWidth-2*x
   ThemeHeight=WindowHeight-2*y
   close #1

   WindowWidth  = bmpw + ThemeWidth-2
   if WindowWidth > DisplayWidth then WindowWidth = DisplayWidth
   WindowHeight = bmph + ThemeHeight-2
   if WindowHeight > DisplayHeight then WindowHeight = DisplayHeight
   UpperLeftX   = (DisplayWidth - WindowWidth) / 2
   UpperLeftY   = (DisplayHeight - WindowHeight) / 2
   graphicbox #1.g 0,0, WindowWidth , WindowHeight
   open "Alarm" for window_nf as #1
   #1 "trapclose quit"
   loadbmp "image",Mapfile$
   #1.g "down ; background image"
   #1.g "drawsprites"

   global BGPX, BGPY
   global BGX, BGY
   global type,x, y, w, h, zone, objects, currentobject, iconimg$, maskimg$, mappath$, mapID$, comp, MaxIcons, Icontype, IconSize
   DIM object(1000,10)
   z=1 'zone object assigned to
   type=2 'type of object
   x=3 'x
   y=4 'y
   w=5 'width of object
   h=6 'hight of object
   MaxIcons = 40
   Icontype = 0
   IconSize = 40

   #1.g "when leftButtonDouble coords"

   call LoadMapImages
   call LoadObjects
   '#1.g "drawsprites"

   'Search for zonenumber and display on map
   FOR findzone = 0 to objects
       IF Zone = object(findzone,zone) THEN
       print "item found!"
       TRACE 3
       'print "object position "; object(findzone, x) ;" ";object(findzone, y)
       'print "background x y "; object(findzone, x) ;" ";object(findzone, y)

       'Collect object position from array
       objectposX = object(findzone, x)
       objectposY = object(findzone, y)
       Print "objectposX :"; objectposX ; " objectposY :" ; objectposY

       'Collect Window dimensions then find the center
       centreWindowX = WindowWidth / 2
       centreWindowY = WindowHeight / 2
       print "centreWindowX :"; centreWindowX ; " centreWindowY :" ;centreWindowY

       'Collect Image dimensions the find the center, don't think we actually need this.
       centreImageW = bmpw / 2
       centreImageH = bmph / 2
       print "centreImageW :"; centreImageW ; " centreImageH :" ;centreImageH

       'Calculate where to place the BG so the object is centred on the screen
       'BGPX = Backgground Position X and Y

       IF objectposX > centreWindowX THEN
           valueX = objectpositionX - centreWindowX
           print "value X "; valueX
           BGPX = valueX - objectpositionX
       ELSE
           valueX = objectpositionX - centreWindowX
           print "value X "; valueX
           BGPX = valueX + objectpositionX
       END IF

       IF objectposY > centreWindowY THEN
           valueY = objectpositionY - centreWindowY
           print "value Y "; valueY
           BGPY = valueY - objectpositionY
       ELSE
           valueY = objectpositionY - centreWindowY
           print "value Y " ;valueY
           BGPY = valueY + objectpositionY
       END IF

       'Reload objects with the new calculation info, so we move the objects with the BackGround
       CALL LoadObjects

       Print "BGPX: "; BGPX ; " BGPY: ";BGPY

       'Move background
       #1.g "backgroundxy ";BGPX;" "; BGPY

       'Draw object in the middle of the screen
       #1.g "drawsprites"
       #1.g "DRAWBMP activation "; BGPX;" "; BGPY

           found = 1
       END IF
   NEXT

   IF found = 0 THEN NOTICE "An alarm occurred but no matching zone in database!"

WAIT

'Sub to get info and display when object is double clicked.
SUB coords handle$, xpos, ypos
   print "Double Clicked on "; handle$ , xpos, ypos
   'Get window coords
   STRUCT Rect, x1 As Long, y1 As Long, x2 As Long, y2 As Long : MapCordshandle = hwnd(#1)
   CallDLL #user32, "GetWindowRect", MapCordshandle as uLong, Rect As struct, result As Long
   CurrentMapWinPosX = Rect.x1.struct : CurrentMapWinPosY = Rect.y1.struct  'upper y coord

       for n = 1 to objects
       if xpos>object(n,x) and xpos<object(n,x)+20 and ypos>object(n,y) and ypos<object(n,y)+20 then
          print "Item: ";n
          UpperLeftX = CurrentMapWinPosX + MouseX: UpperLeftY = CurrentMapWinPosY + MouseY + 10 : WindowWidth = 50 : WindowHeight = 30
          STATICTEXT #comp.1, "", 5, 5, 50, 18
          IF comp = 0 THEN
               comp = 1
               OPEN "Component" FOR window_popup as #comp
               #comp.1 "!font Trebuchet 12 BOLD"
               #comp.1, object(n,zone)
               #1.g "when mouseMove [CloseCoordsCompWindow]"
          END IF
          exit for
          end if
       next
END SUB

[CloseCoordsCompWindow]
   IF comp THEN
       CLOSE #comp
      #1.g "when mouseMove"
      comp = 0
   END IF
WAIT

SUB quit h$
   CLOSE #1
   END
END SUB


'This loop creates images for the main mapping window
SUB LoadMapImages
   FOR a = 1 to MaxIcons
       LOADBMP "i" ; a , maskimg$ ; a ;".bmp"
   NEXT
   LOADBMP "activation", iconimg$ + "activation.bmp"
END SUB


'*************************************************LOAD MAP*********************************************************

SUB LoadObjects

   OPEN mappath$ + mapID$ + ".txt" FOR INPUT AS #readFile
   objects=0
   WHILE NOT(EOF(#readFile))
   objects = objects + 1
   INPUTCSV #readFile, a$, b$, c$, d$, e$, f$, g$, h$
   object(objects,zone) = VAL(a$)
   object(objects,type) = VAL(b$)  ' Icontype
   object(objects,x) = VAL(c$)     ' x position
   object(objects,y) = VAL(d$)     ' y position
   object(objects,w) = VAL(e$)
   object(objects,h) = VAL(f$)
   object(objects,7) = VAL(g$)
   object(objects,8) = VAL(h$)
   #1.g "addsprite s";objects;" i";object(objects,type)
   #1.g "spritexy s";objects;" ";object(objects,x) + BGPX;" ";object(objects,y) + BGPY
   WEND
   #1.g "drawsprites"
   CLOSE #readFile
END SUB
'*********************************************END LOAD MAP*********************************************************

'This is a Rod function to get the bmp size, I still have no clue how this actually works but it does so leave it alone!
function value(x$)
   select case len(x$)
       case 1
       value = asc(x$)
       case 2
       value=asc(mid$(x$,1,1))
       value=value+(asc(mid$(x$,2,1))*256)
       case 3
       value=asc(mid$(x$,1,1))
       value=value+(asc(mid$(x$,2,1))*256)
       value=value+(asc(mid$(x$,3,1))*65536)
       case 4
       value=asc(mid$(x$,1,1))
       value=value+(asc(mid$(x$,2,1))*256)
       value=value+(asc(mid$(x$,3,1))*65536)
       value=value+(asc(mid$(x$,4,1))*16777216)
   end select
end function



I've included all the images and a larger test map with data file in case you need it.
Maps.zip (338.53 KB)


Thank you in advance.

[Brandon Parker]

See if this is what you are looking for ...

BGPX = (objectposX - centreWindowX)
BGPY = (objectposY - centreWindowY)

It seems to work for me when I put a marker on the bitmap at the location that was defined and the software prepositions the background image.

Here is how it looks when run with Zone = 1001 with its marker.




{:0)

Brandon Parker

[Brandon Parker]

And ... here is how it looks when run with Zone = 4 with its marker.



I did not do anything with any object stuff.  I only used the two lines above.

I hope this helps out ...

{:0)

Brandon Parker

[Tasp]

I checked your images and indeed  that is exactly where the zone/objects are! So thats got to be the solution.

However where are you putting these lines of code? Are you replacing the IF THEN block as this doesn't work for me.

I also really like adding the Zone number and coord to the screen, I assume you did that with code and not paint after!

EDIT:

Wait, if I replace the IF THEN with those line, it indeed does centre the screen. It took me a while to realise you was saying, it centers the screen but doesn't do move the objects about. 
It took a few rereads and a while for my brain to catch up!

Thanks for the seemingly simple fix! Very Grateful. 

[Brandon Parker]

No problem ...


{:0)

Brandon Parker