Type As Array

[Pot Noodle]

Hi guys any one know whats wrong with this?  It's in BlitzMax

Type RGBQUAD
    Field rgbBlue:Byte
    Field rgbGreen:Byte
    Field rgbRed:Byte
    Field rgbReserved:Byte
End Type

Global bmiColors:RGBQUAD = New RGBQUAD[255]

This is how I would use it: bmiColors[a].rgbBlue = 10
Just can't see the trees for the wood.
Thanks

[Hotshot]

far as I know....this one should work

Code Select Expand


Type RGBQUAD
    Field rgbBlue:Byte
    Field rgbGreen:Byte
    Field rgbRed:Byte
    Field rgbReserved:Byte
End Type

Global bmiColors:RGBQUAD = New RGBQUAD


But what you trying to do is doing Type with Arrays?

I am not sure if that what you want

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Type RGBQUAD
    Field rgbBlue:Byte[255]
    Field rgbGreen:Byte[255]
    Field rgbRed:Byte[255]
    Field rgbReserved:Byte[255]
End Type

Global bmiColors:RGBQUAD = New RGBQUAD


[Pot Noodle]

I have tryed that, I just get an error "bmicolors can't be Indexed" 

[Jim]

yeah, that would give you

Code Select Expand


bmiColors.rgbBlue[0]
to
bmiColors.rgbBlue[255]


You want

Code Select Expand


Type RGBQUAD
    Field rgbBlue:Byte
    Field rgbGreen:Byte
    Field rgbRed:Byte
    Field rgbReserved:Byte
End Type

Global bmiColors:RGBQUAD[] = New RGBQUAD[256]

note the extra pair of square brackets after RGBQUAD.  There are 256 entries in the palette, not 255.
You could also do

Code Select Expand


Global bmiColors:RGBQUAD[256]


Jim

[Pot Noodle]

Thanks Jim, Brill, them Blitzmax arrays do my head in. 

Unhandled Exception:Attempt to access field or method of Null object

on this line:
For a = 1 To 127
        bmiColors[a].rgbGreen = 255 - 2 * a <----- Error
        bmiColors[a].rgbRed = 2 * a
    Next

[Jim]

OK, so each of those array slots is just a 'pointer' to an RGBQUAD, you need to allocate some space for the data.

Code Select Expand


For a = 1 To 127
  bmiColors[a] = New RGBQUAD
  bmiColors[a].rgbGreen = 255 - 2 * a
  bmiColors[a].rgbRed = 2 * a
Next

I'm not sure if it's necessary to do that if you used

Code Select Expand


Global bmiColors:RGBQUAD[] = New RGBQUAD[256]

Not sure.  I've never used BlitzMax.

Jim