Loading bmp with sprite mask code causing index error

[Noble]

Hello all!

It has been way to long since I have been on here. Anyway, I seem to be in a bit of a pickle. I am trying to use the sprite mask code (either the code posted in the help file or from Alyce's website). I am running Windows 11 and LB 4.5.1. 

I load up the code in the editor and run it. It asks for a filename. I supply a valid bmp (so I think) and ask it to start. Instead of getting anything on the screen I get an error message:

Runtime error: index: 771 is outside of collection bounds.

I am not sure what is causing the issue. I debugged the code from Alyce's site and it is blowing up on this line:


loadbmp "bm" , bitmap$


This code is right after the filedialog requesting a filename. Looking at the bitmap$ variable I see that the drive/path/filename.ext is supplied properly. I have tried that as admin and normal user. Multiple bmp's. Also tried putting the bmp into multiple locations on my harddrive to see if that helped.

Thoughts?

[Walt Decker]

My guess is something in the parser. You might try this:

loadbmp "bm", bmpname$

or

loadbmp"bm",bmpname$

[Carl Gundel]

Jan 7, 2022 8:57:10 GMT -5 Noble said:

Hello all!

It has been way to long since I have been on here. Anyway, I seem to be in a bit of a pickle. I am trying to use the sprite mask code (either the code posted in the help file or from Alyce's website). I am running Windows 11 and LB 4.5.1. 

I load up the code in the editor and run it. It asks for a filename. I supply a valid bmp (so I think) and ask it to start. Instead of getting anything on the screen I get an error message:

Runtime error: index: 771 is outside of collection bounds.

I am not sure what is causing the issue. I debugged the code from Alyce's site and it is blowing up on this line:


loadbmp "bm" , bitmap$


This code is right after the filedialog requesting a filename. Looking at the bitmap$ variable I see that the drive/path/filename.ext is supplied properly. I have tried that as admin and normal user. Multiple bmp's. Also tried putting the bmp into multiple locations on my harddrive to see if that helped.

Thoughts?

Liberty BASIC will choke on some bitmap formats.  People have had luck opening a bitmap in mspaint (press Ctrl+Esc and type mspaint and Enter) and then resaving it.  This can make a bitmap readable from Liberty BASIC oftentimes.

[Noble]

I have been using Paint.Net for most of the images with color depth set to auto. I tried loading one in MSPaint and resaving but that did not help. So, I created a new image in MSPaint and saved it. That worked. I went back to Paint.Net and changed the color depth from auto to be 24-bit and saved it. It worked too. It seems to be a color depth issue maybe?

[Carl Gundel]

Jan 7, 2022 10:14:08 GMT -5 Noble said:

I have been using Paint.Net for most of the images with color depth set to auto. I tried loading one in MSPaint and resaving but that did not help. So, I created a new image in MSPaint and saved it. That worked. I went back to Paint.Net and changed the color depth from auto to be 24-bit and saved it. It worked too. It seems to be a color depth issue maybe?

Perhaps.  Hard to be sure.  There have been variations of bitmap file formats since the VisualSmalltalk libraries were written that LB is built atop.

[tsh73]

Noble,
Please post faulty bitmap so we can see it.

Or run this code and tell us the difference from ones what reads OK

(I remember LB refusing to load bitmaps with optimized palette, if palette saved had less then 256 colors.
I got such BMPs from the GIMP )


'read BMP pixel by pixel
'by tsh73
'compiled from various sources (sources in C and QB) to Just Basic 1.01
'10 May 2007
'released to public domain
' - to all Just Basic users who find this interesting (or useful)

'all color depths I've seen (1, 4, 8 and 24)
'no compression
'examples created by Gimp from very old file of unknown origin YROSE.JPG

filedialog "Open BMP file", "*.bmp", fname$
open fname$ for binary as #1
print "File "+stripPath$(fname$) +" length is ";lof(#1)

print " ======= BMPHeader ============"
print "ValidID (first 2 bytes) is: (should be BM)";tab(45);readStr$(2)
print "fileSize";tab(45);readLong()
print "reserved";tab(45);readLong()
offset = readLong()
print "offset";tab(45);offset
print " ======= WindowsInfoHeader ==========="
print "SizeOfHeader (should be 40)";tab(45); readLong()
BMwidth = readLong()
print "width";tab(45); BMwidth
BMheight = readLong()
print "height";tab(45); BMheight
print "planes (should be 1)" ;tab(45);read2Bytes()
bpp = read2Bytes()
print "BitsPerPixel (bpp)";tab(45); bpp
CompressMethod = readLong()
print "CompressMethod";tab(45); CompressMethod;" ";word$("Uncompressed|8 Bit RLE Compression|4 Bit RLE Compression|bi_bitfields",CompressMethod+1,"|")
imagebytes = readLong()
print "imagebytes";tab(45); imagebytes
print "xres";tab(45);  readLong()
print "yres";tab(45);  readLong()
colch = readLong()
print "ColorsUsed";tab(45); colch  ' could be 0 - All Used
print "ImportantColors";tab(45);  readLong()

print " ======= calculated info ==========="
currPos = LOC(#1)
print "curr pos is ";tab(45);currPos
print "for palette left ";tab(45); offset - currPos
print "for palette colors ";tab(45); (offset - currPos)/4
' ==  colch
if colch = 0 then colch = (offset - currPos)/4  '???
'because it could be 0 - All Used
print "imagebytes + offset " ;tab(45); imagebytes + offset

byteWidth = BMwidth*bpp/8
if int(byteWidth)<> byteWidth then byteWidth= int(byteWidth)+1
actualWidth = byteWidth
if actualWidth mod 4 <>0 then  actualWidth = actualWidth + 4-actualWidth mod 4
'padded to 4 bytes
print "line length in bytes ";tab(45);actualWidth
print "imagebytes / line length in bytes ";tab(45);imagebytes / actualWidth

if inlist(CompressMethod, "1,2")  then
   print "Compressed bitmaps (RLE encoding) are not supported"
   close #1
   end
end if

if not(inlist(bpp,"1,4,8,16,24,32")) then
   print "Color depth (bits per pixel, bpp) other then 1,4,8,16,24,32 is not supported"
   close #1
   end
end if

if  colch = 0 then
   print " ======= No palette present ==========="
   goto [skipPalette]
end if

'** palette goes here
dim rpal(255),gpal(255),bpal(255),spal$(255)
for i = 0 to colch-1
   bpal(i) = readByte()
   gpal(i) = readByte()
   rpal(i) = readByte()
   spal$(i) = str$( rpal(i))+" "+str$( gpal(i))+" "+str$( bpal(i))
   'print  spal$(i)
   dummy$ = input$(#1, 1)  'skip one byte
next i

if CompressMethod = 3 then
   print "Color masks are:"
   i = 0
   redMask = ((rpal(i)*256)+ gpal(i))*256+ bpal(i)
   print "Red";  tab(8); hex$(redMask)
   i = 1
   greenMask = ((rpal(i)*256)+ gpal(i))*256+ bpal(i)
   print "green";tab(8); hex$(greenMask)
   i = 2
   blueMask = ((rpal(i)*256)+ gpal(i))*256+ bpal(i)
   print "blue"; tab(8); hex$(blueMask)
end if

'show palette
WindowWidth = 400
WindowHeight = 400
open "Palette" for graphics_nf_nsb as #pal
print #pal, "trapclose [endPalette]"

for i =0 to 15
   for j =0 to 15
       y = i*20+20
       x = j*20+20
       x1 = x+15
       y1 = y+15
       ind = i*16+j
       if ind > colch-1 then exit for
       print #pal, "backcolor ";spal$(ind)
       print #pal, "up"
       print #pal, "goto ";x;" ";y
       print #pal, "down"
       print #pal, "boxfilled ";x1;" ";y1

   next j
   if ind > colch-1 then exit for
next i
print #pal, "flush"      'make the graphics stick
print " ======= palette present ==========="
print colch; " colors"
print "close palette window to view image"
wait

[endPalette]
close #pal

[skipPalette]

startTime = time$("ms")
'** now the picture itself...
WindowWidth = BMwidth+8 ' + window border
'WindowHeight = BMheight+20  ' + window header, win2000 style
WindowHeight = BMheight+34  ' + window header, XP style
open "picture" for graphics_nf_nsb as #gr1
'print #gr1, "trapclose Quit"
print #gr1, "trapclose [gr1End]"
print #gr1, "down"       'ready to draw
print #gr1, "north ; turn 90"

oldInd = 999    'magic
FOR y =  BMheight-1 TO 0 step -1           ' Countdown for upsidedown image
   aLine$ = readStr$(actualWidth)
   print #gr1, "place 0 ";y
   FOR x = 0 TO BMwidth-1
   select case bpp
   case 1
       byte = asc(mid$( aLine$, int(x/8)+1, 1))
'        pos = 7 - x mod 8
'        pow2 = 2^pos
'        if (byte and pow2) <> 0 then
'            ind = 1
'        else
'            ind = 0
'        end if
       ind = ((byte and (2^(7 - x mod 8))) <> 0)
       if oldInd <> ind then
           print #gr1, "color "; spal$(ind)
           oldInd = ind
       end if
       print #gr1, "go 1"
   case 4
       byte = asc(mid$( aLine$, int(x/2)+1, 1))
       if x mod 2 <> 0 then
           ind = byte mod 16
       else
           ind = int(byte / 16)
       end if
       if oldInd <> ind then
           print #gr1, "color "; spal$(ind)
           oldInd = ind
       end if
       print #gr1, "go 1"
   case 8
       ind = asc(mid$( aLine$, x+1, 1))
       if oldInd <> ind then
           print #gr1, "color "; spal$(ind)
           oldInd = ind
       end if
       print #gr1, "go 1"

   case 16
       bytes = byte2Num(mid$( aLine$, 2*x+1, 2))
       'if  CompressMethod = 3 then
           r =  (bytes AND redMask) /256
           g =  (bytes AND greenMask) / 32 * 4
           b =  (bytes AND blueMask) * 8
       'end if
       print #gr1, "color ";r;" ";g;" ";b
       print #gr1, "go 1"
   case 24
       r = asc(mid$( aLine$, 3*x+3, 1))
       g = asc(mid$( aLine$, 3*x+2, 1))
       b = asc(mid$( aLine$, 3*x+1, 1))
       print #gr1, "color ";r;" ";g;" ";b
       print #gr1, "go 1"
   case 32
       r = asc(mid$( aLine$, 4*x+3, 1))
       g = asc(mid$( aLine$, 4*x+2, 1))
       b = asc(mid$( aLine$, 4*x+1, 1))
       print #gr1, "color ";r;" ";g;" ";b
       print #gr1, "go 1"
   end select
   NEXT x
next y

print #gr1, "flush"      'make the graphics stick
'print #gr1, "redraw"
endTime=time$("ms")
print
print "Drawing BMP (not incl. palette) took ";
print endTime-startTime; " milliseconds"
close #1

wait

[gr1End]
close #gr1

end

' some functions ********************************************8
function readByte()
   readByte = asc(input$(#1, 1))
end function

function readLong()
   readLong = byte2Num(input$(#1, 4))
end function

function read2Bytes()
   read2Bytes = byte2Num(input$(#1, 2))
end function

function readStr$(n)
    readStr$ = input$(#1, n)
end function

function byte2Num(c$)
   res = 0
   for i = len(c$) to 1 step -1    'lower byte first
       res = res * 256+asc(mid$(c$,i,1))
   next i
   byte2Num = res
end function

function stripPath$(fname$)
   found = 0
   for i = len(fname$) to 1 step -1
       c$=mid$(fname$,i,1)
       'print i; c$,
       if c$="\" then
           found = 1
           exit for
       end if
   next i
   if found then
        stripPath$ = mid$(fname$,i+1)
   else
       stripPath$ = fname$
   end if
end function

function inlist(aVal, list$)
   list$ = ","+list$+","
   inlist = (instr(list$, ","+str$(aVal)+",")<>0)
end function

Function hex$(n)
   h$ = ""
   do
       h$ = mid$("0123456789ABCDEF", (n mod 16)+1, 1) + h$
       n = int(n/16)
   loop while n > 0
   hex$ = h$
End Function


[Noble]

I will give that a try. Right now I have noticed that if I set the color depth to 24-bit all the bmp's that I have tried have worked. Not sure that is the golden depth or not but it has worked for me so far. I basically use Paint.Net the most. Thanks for all the help. I have missed this place.

[Walt Decker]

I think bit depth is not the problem. I have created 32-bit top-down dibsections and used them with "drawbmp" and have had no problems.

Try loading the bitmap with LoadImage() API. If it works assign the image with LOADBMP "SOMETAG", BmpHandle.