How would you translate this to PB?

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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by raphael.

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static char bitmapbuffer[sizeof(BITMAPINFO)+16];
static BITMAPINFO *bitmap_header;

for (cc = 0; cc bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
bitmap_header->bmiHeader.biPlanes = 1;
bitmap_header->bmiHeader.biBitCount = 32;
bitmap_header->bmiHeader.biCompression = BI_BITFIELDS;
bitmap_header->bmiHeader.biWidth = surface_width;
bitmap_header->bmiHeader.biHeight = -surface_height;
((unsigned long *)bitmap_header->bmiColors)[0] = 0x00FF0000;
((unsigned long *)bitmap_header->bmiColors)[1] = 0x0000FF00;
((unsigned long *)bitmap_header->bmiColors)[2] = 0x000000FF;
thanks in advance for any hints!
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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by Thomas.

It's incomplete so you cannot translate this. In general this is just pointers and structures.
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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by raphael.
Originally posted by Thomas
It's incomplete so you cannot translate this
well, it is complete. what information do you need?
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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by Thomas.

the definition of the bitmap fields?
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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by raphael.

they are part of the win32-api (wingdi.h)

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typedef struct tagBITMAPINFOHEADER{
        DWORD      biSize;
        LONG       biWidth;
        LONG       biHeight;
        WORD       biPlanes;
        WORD       biBitCount;
        DWORD      biCompression;
        DWORD      biSizeImage;
        LONG       biXPelsPerMeter;
        LONG       biYPelsPerMeter;
        DWORD      biClrUsed;
        DWORD      biClrImportant;
} BITMAPINFOHEADER, FAR *LPBITMAPINFOHEADER, *PBITMAPINFOHEADER;

typedef struct tagBITMAPINFO {
    BITMAPINFOHEADER    bmiHeader;
    RGBQUAD             bmiColors[1];
} BITMAPINFO, FAR *LPBITMAPINFO, *PBITMAPINFO;
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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by ebs.

raphael,

The BITMAPINFO and BITMAPINFOHEADER structures have PB definitions. You can see them in the Structure Viewer tool in the editor.

Are you sure the C code is correct? I'm a little puzzled because the char array bitmapbuffer is initialized to sizeof(BITMAPINFO) + 16 bytes (8 + 16 = 24 bytes), but the for statement initializes sizeof(BITMAPINFOHEADER) + 16 bytes (40 + 16 = 56 bytes).

Let me know,
Eric
Originally posted by raphael

Code: Select all

static char bitmapbuffer[sizeof(BITMAPINFO)+16];
static BITMAPINFO *bitmap_header;

for (cc = 0; cc bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
bitmap_header->bmiHeader.biPlanes = 1;
bitmap_header->bmiHeader.biBitCount = 32;
bitmap_header->bmiHeader.biCompression = BI_BITFIELDS;
bitmap_header->bmiHeader.biWidth = surface_width;
bitmap_header->bmiHeader.biHeight = -surface_height;
((unsigned long *)bitmap_header->bmiColors)[0] = 0x00FF0000;
((unsigned long *)bitmap_header->bmiColors)[1] = 0x0000FF00;
((unsigned long *)bitmap_header->bmiColors)[2] = 0x000000FF;
thanks in advance for any hints!
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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by raphael.
Originally posted by ebs
The BITMAPINFO and BITMAPINFOHEADER structures have PB definitions. You can see them in the Structure Viewer tool in the editor.
i just wanted to show thomas the 'original' definition because he asked

Code: Select all

Are you sure the C code is correct? I'm a little puzzled because the char array bitmapbuffer is initialized to sizeof(BITMAPINFO) + 16 bytes (8 + 16 = 24 bytes), but the for statement initializes sizeof(BITMAPINFOHEADER) + 16 bytes (40 + 16 = 56 bytes).
yes, the code is correct. i'm not sure if the structures are correct in purebasic though.
isn't 'bmiHeader' in BITMAPINFO of type BITMAPINFOHEADER instead of long?
BITMAPINFO would be bigger than BITMAPINFOHEADER then. that's what i understand from the wingdi.h at least.

so, that's the mainpart i don't understand:
shouldn't

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bitmap_header->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
be like

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bitmap_header\bmiHeader\biSize = sizeof(BITMAPINFOHEADER)
in pb?

i'd be a happy man if you could help me...
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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by ebs.

raphael,
yes, the code is correct. i'm not sure if the structures are correct in purebasic though. isn't 'bmiHeader' in BITMAPINFO of type BITMAPINFOHEADER instead of long? BITMAPINFO would be bigger than BITMAPINFOHEADER then. that's what i understand from the wingdi.h at least.
Yes, I looked it up in the APIViewer and I agree with you. In PureBasic, I think this is correct:

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Structure BITMAPINFO
  bmiHeader.BITMAPINFOHEADER
  bmiColors.b[4]
EndStructure
NOT

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Structure BITMAPINFO
  bmiHeader.l
  bmiColors.l
EndStructure
Maybe someone thought that the bmiHeader element was supposed to be a pointer (long), but I don't think so. You'll notice that I made bmiColors an array of 4 bytes (like the RGBQUAD structure) instead of a long. This should be the same thing, just a little easier to assign the colors individually.
shouldn't
bitmap_header->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);

be like
bitmap_header\bmiHeader\biSize = sizeof(BITMAPINFOHEADER)

in pb?
Yes, but the bitmap_header variable is just a pointer to the bitmapbuffer memory, so I think you can do something like this:

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; note new structure which includes the extra 16 bytes
Structure BITMAPINFOPLUS16
  bmiHeader.BITMAPINFOHEADER
  bmiColors.b[4]
  extrabytes.b[16]
EndStructure 
  
; all fields should be initialized to 0 when created
bitmapbuffer.BITMAPINFOPLUS16

bitmapbuffer\bmiHeader\biSize = SizeOf(BITMAPINFOHEADER)
bitmapbuffer\bmiHeader\biPlanes = 1
bitmapbuffer\bmiHeader\biBitCount = 32
bitmapbuffer\bmiHeader\biCompression = #BI_BITFIELDS
bitmapbuffer\bmiHeader\biWidth = surface_width
bitmapbuffer\bmiHeader\biHeight = -surface_height
bitmapbuffer\bmiColors[0] = $ff
bitmapbuffer\bmiColors[1] = $ff
bitmapbuffer\bmiColors[2] = $ff
I'm not sure why the C code uses longs when setting the bmiColors values. I believe they are bytes, not longs, as the definition of RGBQUAD is an array of four bytes.

Hope this helps,
Eric
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BackupUser
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Post by BackupUser »

Restored from previous forum. Originally posted by raphael.

so i was kinda right and the pb-structure isn't correct thus making
a translation impossible (without defining an own structure).
fred, another topic on your list? :wink:

thank you very much for your effort!
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